TECHNICAL FIELD
[0001] The present invention relates to an air-conditioner design support device.
BACKGROUND ART
[0002] In recent years, in order to reduce environmental load, air conditioners in which
a CFC substitute gas is used as refrigerant have been developed. As the refrigerant,
mildly flammable (flammable) A2L refrigerants, such as hydrofluorocarbon (HFC) type
R32, are used, for example.
[0003] When a mildly flammable (flammable) A2L refrigerant is used in an air conditioner,
a safety measure against refrigerant leak is required. In particular, when the amount
of refrigerant used relative to the volume of the space to be air-conditioned is large,
a safety measure guideline is established, as according to Non-Patent Document 1.
[0004] Non-Patent Document 1 indicates that a safety measure is necessary when the refrigerant
concentration of a room (charge ratio) calculated from room volume and the amount
of refrigerant based on the pipe length and the like exceeds a predetermined threshold
value.
CITATION LIST
NON PATENT LITERATURE
[0005] Non-Patent Literature 1: Guideline of design construction for ensuring safety against
refrigerant leak from commercial air conditioners using lower flammability (A2L) refrigerant,
JRA GL-16: 2016, The Japan Refrigeration and Air Conditioning Industry Association,
published on September 30, 2016
SUMMARY OF THE INVENTION
PROBLEMS TO BE SOLVED BY THE INVENTION
[0006] However, it is a cumbersome work to input room volume and the amount of refrigerant
manually from design drawing, and to determine the need for a safety measure from
calculation results. In addition, such work is difficult for a worker who is not versed
in the calculation method and the like.
[0007] Thus, the present invention relates to a technology which makes it possible to easily
determine the need for a safety measure with respect to an air conditioner.
SOLUTION TO THE PROBLEMS
[0008] In order to solve the problem, an air-conditioner design support device according
to an aspect of the present invention includes a read means which reads data concerning
a design drawing for an air conditioner describing an indoor device, an outdoor device,
a space to be air-conditioned, and a pipe; an acquisition means which acquires, from
the data concerning the design drawing that have been read, data concerning the indoor
device, the outdoor device, the space to be air-conditioned, and the pipe; and a determination
means which calculates the amount of refrigerant required for the air conditioner
based on the acquired data concerning the indoor device, the outdoor device, and the
pipe, calculates the volume of the space to be air-conditioned based on the acquired
data concerning the space to be air-conditioned, determines the need for a safety
measure with respect to the space to be air-conditioned based on the amount of refrigerant
and the volume, and outputs a determination result.
ADVANTAGEOUS EFFECTS OF THE INVENTION
[0009] According to the present invention, the need for a safety measure with respect to
an air conditioner can be easily determined.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010]
Fig. 1 is a block diagram of the configuration of an air-conditioner design support
device according to an embodiment.
Fig. 2 is a schematic diagram of a design drawing describing the room layout of a
building and an air conditioner installation state.
Fig. 3 is an illustration of a drawing depicting constituent elements that have been
recognized.
Fig. 4 is a flowchart of a procedure performed in the design support device for outputting
an indication as to whether a safety measure is required with respect to refrigerant
leak.
DESCRIPTION OF THE EMBODIMENTS
[0011] In the following, an air-conditioner design support device 1 according to an embodiment
of the present invention will be described.
[0012] Fig. 1 is a block diagram of the configuration of the air-conditioner design support
device 1 according to the embodiment.
[0013] As illustrated in Fig. 1, the air-conditioner design support device 1 includes a
main body device 2, an input device 3, a display 4, and an image acquisition device
5.
[0014] The main body device 2 is configured, for example, from a general-purpose computer
system including a processor and a memory, and constituent elements or functions provided
in the main body device 2 are implemented by executing a computer program, for example.
The computer program may be stored in a computer-readable recording medium. The input
device 3, the display 4, and the image acquisition device 5 are connected to the main
body device 2. The input device 3 may be a keyboard, a pointing device and the like.
The display 4 may be a display and the like. The image acquisition device 5 may be
a scanner or a camera, for example.
[0015] The main body device 2 is provided with: a refrigerant characteristics storage device
31; a refrigerant amount storage device 32; a read device 41; a constituent element
recognition device 42; a dimension acquisition device 43; a pipe diameter/pipe length
acquisition device 44; a room height acquisition device 45; a type/capacity acquisition
device 46; and a determination device 47.
[0016] The design support device 1 performs a process of, with respect to an air conditioner
in which a mildly flammable (A2L) refrigerant is used; reading data concerning a design
drawing; recognizing constituent elements, such as an indoor device and an outdoor
device, from the data; acquiring information concerning the constituent elements;
and determining whether a safety measure with respect to refrigerant leak is necessary.
If a safety measure is necessary, a worker selects a measure and reflects the measure
in the design drawing, and determines whether an allowable concentration is satisfied.
In the present embodiment, the refrigerant is R32.
[0017] In the refrigerant characteristics storage device 31, types/characteristics of mildly
flammable (A2L) refrigerant are stored, as indicated in the following Table 1.
(Table 1)
Safety class |
Type of refrigerant |
LFL (kg/m3) |
1/4LFL |
Molecular weight |
Maximum refrigerant amount (kg) |
A2L |
R32 |
0.307 |
0.0768 |
52 |
59.8 |
R1234yf |
0.289 |
0.0723 |
114 |
56.3 |
R1234ze(E) |
0.303 |
0.0758 |
114 |
59.0 |
LFL and maximum refrigerant amount are in accordance with ISO5149-1 |
LFL values are those in the case of dry conditions (23°C, 50%RH) |
[0018] Table 1 corresponds to Table 1 of Non-Patent Document 1, in which LFL refers to the
lower flammability limit according to ISO817 indicating the minimum concentration
of the refrigerant capable of propagating a flame through a homogeneous mixture of
the refrigerant and air.
[0019] The refrigerant amount storage device 32 stores the amounts of refrigerant corresponding
to the type/capacity of the indoor device/outdoor device, and the additional amount
of refrigerant corresponding to pipe diameters.
[0020] The read device 41 reads image data of the design drawing 20. The image data are
data concerning an image of the design drawing 20 acquired by the image acquisition
device 5.
[0021] Fig. 2 is a schematic diagram of the design drawing 20 describing the room layout
of a building 10 and an air conditioner installation state.
[0022] The design drawing 20 describes rooms 11 to 14 in the building 10; the indoor devices
101 to 104 provided in the rooms 11, 13, and 14; doors 501 to 503 for entering and
exiting the rooms 11, 13, and 14; ventilation devices 301, 302; pipes a to g; and
an outdoor device 200 outside the building 10. Colors corresponding to the respective
constituent elements may be determined in advance, and, before the design drawing
20 is acquired by the image acquisition device 5, the constituent elements of the
design drawing 20 may be colored by the worker, using a marker pen and the like. For
example, the rooms 11 to 14 may be colored by being enclosed using a red pen; the
indoor devices 101 to 104 may be colored by being enclosed using a blue pen; the outdoor
device 200 may be colored by being enclosed using a green pen; and the pipes a to
g may be colored by being traced using a yellow pen.
[0023] The constituent element recognition device 42 recognizes, from the image data that
have been read, the constituent elements including the rooms, piping, a ventilating
fan, the indoor devices, and the outdoor device, on the basis of structure/shape and
the like. When the constituent elements are colored, the constituent elements may
be recognized on the basis of the respective colors. The constituent element recognition
device 42 then displays the result of the recognizing on the display 4. For example,
the display 4 displays a drawing 21 in which the recognized constituent elements are
represented diagrammatically, as depicted in Fig. 3, and Table 2 shown below in which
the recognized constituent elements are numbered. The displayed drawing is provided
with numbering numbers. The numbers provided are similar to the numbers used for describing
the design drawing 20 with reference to Fig. 2. Regarding the pipes a to g, each of
the sections between the indoor devices 101 to 104 or the outdoor device 200 and a
piping branch portion, and each of the sections between adjacent branch portions are
recognized as individual pipes.
(Table 2)
Constituent element |
Room |
Pipe |
Outdoor device |
Indoor device |
Number |
11 |
a |
200 |
101 |
12 |
b |
- |
102 |
13 |
c |
- |
103 |
14 |
d |
- |
104 |
- |
e |
- |
- |
- |
f |
- |
- |
- |
g |
- |
- |
[0024] If there is any discrepancy from the design drawing 20 on the basis of the drawing
and Table 2 being displayed, the worker makes, for example, correction on and addition
to the discrepancy as appropriate using the input device 3. The constituent element
recognition device 42 may also be configured to recognize the ventilation devices
301, 302. In Fig. 3, a mechanical ventilation device 300 and a cut-off valve 400,
which are additional constituent elements, are depicted, in addition to the constituent
elements that have been recognized.
[0025] The dimension acquisition device 43 acquires reference dimensions from the image
data that have been read. For example, if a part of the design drawing 20 indicates
dimensions, such as the lengths of the sides of the building 10 or the rooms 11 to
14, or the lengths of the pipes a to g, such dimensions are acquired as the reference
dimensions. Then, the dimension acquisition device 43, on the basis of the acquired
dimensions, calculates the lengths of the sides of each of the rooms 11 to 14 and
the floor areas thereof, and displays the lengths and floor areas on the display 4.
The worker, if the floor areas and the like being displayed differ from the design
drawing 20, makes corrections, as appropriate. If the design drawing 20 indicates
the scale, the scale may be acquired as a reference dimension. The dimension acquisition
device 43, if the reference dimensions cannot be acquired, may display an input screen
on the display 4 and prompt the worker to input reference dimensions.
[0026] The pipe diameter/pipe length acquisition device 44 acquires, from the image data
that have been read, the pipe diameter and pipe length of each of the pipes a to g.
For example, if the design drawing 20 indicates the pipe diameter and pipe length
of each of the pipes a to g, the pipe diameter/pipe length acquisition device 44 acquires
the indicated pipe diameter and pipe length as the pipe diameter and pipe length of
each of the pipes a to g. The pipe diameter/pipe length acquisition device 44 displays
the acquired pipe diameter and pipe length on the display 4. The worker, if the pipe
diameter and pipe length being displayed differ from the design drawing 20, makes
corrections, as appropriate. The pipe diameter/pipe length acquisition device 44,
if some or all of the pipe diameters and pipe lengths cannot be acquired, may display
an input screen on the display 4 and prompt the worker to input the pipe diameter
and pipe length.
[0027] The room height acquisition device 45 acquires the height of each of the rooms 11
to 14 from the image data that have been read. For example, if the height of each
of the rooms 11 to 14 is described in the design drawing 20, the height is acquired.
The room height acquisition device 45 displays the acquired height of each of the
rooms 11 to 14 on the display 4. If the height of each of the rooms 11 to 14 being
displayed differs from the design drawing 20, the worker makes corrections, as appropriate.
The room height acquisition device 45, if some or all of the heights of the rooms
11 to 14 cannot be acquired, may display an input screen on the display 4 and prompt
the worker to input the height of each of the rooms 11 to 14.
[0028] The type/capacity acquisition device 46 acquires the type and capacity of the outdoor
device 200 and the indoor devices 101 to 104 from the image data that have been read.
For example, if the type and capacity of the outdoor device 200 and the indoor devices
101 to 104 are described in the design drawing 20, the described type and capacity
are acquired. The type/capacity acquisition device 46 displays the acquired type and
capacity of the outdoor device 200 and the indoor devices 101 to 104 on the display
4. The worker, if the displayed type and capacity differ from the design drawing 20,
makes corrections, as appropriate. If some or all of the types and capacities cannot
be acquired, the type/capacity acquisition device 46 may display an input screen on
the display 4 and prompt the worker to input the type/capacity.
[0029] The determination device 47, on the basis of the type and capacity acquired by the
type/capacity acquisition device 46, the pipe diameter and pipe length acquired by
the pipe diameter/pipe length acquisition device 44, the amount of refrigerant corresponding
to the type/capacity of the indoor devices/outdoor devices stored in the refrigerant
amount storage device 32, and the additional amount of refrigerant corresponding to
the pipe diameter, calculates an amount of refrigerant, and displays the results of
calculation of the amount of refrigerant, shown in Table 3, on the display 4.
(Table 3)
Location |
Pipe diameter (mm) |
Pipe length (m) |
Additional amount of refrigerant (kq/m) |
Refrigerant amount (kg) |
a |
12.7 |
20 |
0.12 |
2.40 |
b |
12.7 |
5 |
0.12 |
0.60 |
c |
9.53 |
3 |
0.07 |
0.21 |
d |
9.53 |
5 |
0.07 |
0.35 |
e |
9.53 |
5 |
0.07 |
0.35 |
f |
6.35 |
4 |
0.03 |
0.12 |
g |
6.35 |
10 |
0.03 |
0.30 |
For outdoor device |
- |
- |
- |
8.00 |
For indoor device |
- |
- |
- |
2.00 |
Total |
- |
- |
- |
14.33 |
[0030] The determination device 47 also, on the basis of the calculated amount of refrigerant,
the height of each of the rooms 11 to 14 acquired by the room height acquisition device
45, and the floor area of each of the rooms 11 to 14 calculated by the dimension acquisition
device 43, determines the need for a safety measure with respect to refrigerant leak
on a room by room basis. The determination device 47 displays, on the display 4, Table
4 shown below as the result indicating the need, and the drawing 21 depicted in Fig.
3, in which the constituent elements recognized by the constituent element recognition
device 42 are diagrammatically represented.
(Table 4)
Room number |
Floor area (m2) |
Ceiling height (m) |
Room volume (m3) |
Full-leak concentration (kg/m3) |
Need for measure |
Shut-off valve position (m) |
Shut-off leak amount (kg) |
Concentration during shut-off valve activation |
11 |
150 |
2.6 |
390 |
0.037 |
No |
- |
- |
- |
12 |
50 |
2.6 |
130 |
0.110 |
- |
- |
- |
- |
13 |
30 |
2.4 |
72 |
0.199 |
Yes |
3 |
0.21 +0.5 = 0.71 |
0.010 OK |
14 |
100 |
2.4 |
240 |
0.060 |
No |
- |
- |
- |
[0031] The determination device 47 calculates the concentration (kg/m
3, refrigerant charge ratio) in the event of leak of all refrigerant in the rooms 11
to 14. If the concentration value is equal to or greater than the value of 1/4 LFL
(allowable concentration) stored in the refrigerant characteristics storage device
31, the determination device 47 indicates "Yes" with respect to the need for a measure.
If smaller, "No" is indicated. At this point in time, the determination device 47
displays only the portion to the left of the column for the need for a measure in
Table 4. While the determination for the need is not being performed with respect
to the room 12 because an indoor device is not arranged therein, the determination
for the need may be performed with respect to the room 12.
[0032] The worker selects a safety measure with respect to the room 13 determined to require
a measure. The worker selects at least one of the cut-off valve 400 and the mechanical
ventilation device 300 depicted as alternatives in Fig. 3. In the present embodiment,
the case in which the cut-off valve 400 has been selected will be described. The worker
selects the cut-off valve 400, and inputs the position for its installation on the
drawing being displayed. The determination device 47, upon detecting that the worker
has made the input, indicates, to the right of the column for the need for a measure
in Table 4, the cut-off valve position, the leak amount at the time of cut-off, and
the concentration (kg/m
3) during the activation of the cut-off valve. If the concentration (refrigerant charge
ratio) in the event of refrigerant leak in the room 13 becomes smaller than the 1/4
LFL value because of the measure, the determination device 47 indicates "OK". That
is, the determination device 47 determines whether the safety measure that has been
input is effective or not. If the concentration in the event of refrigerant leak in
the room 13 becomes equal to or greater than the 1/4 LFL value because of the measure,
the determination device 47 indicates "NG" and prompts the worker to input a safety
measure again.
[0033] The determination device 47, if the calculated concentration in the event of full
leak is outside a range determined by design conditions, indicates "Error" with respect
to the need for a measure. The range determined by the design conditions refers to
a range determined by the room volume, the minimum amount of refrigerant of the indoor
device, and the maximum amount of the refrigerant. The upper limit of the range is
the value (2.49 kg/m
3) determined from the maximum amount of refrigerant (59.8kg in the case of R32) in
Table 1, and the minimum volume (for example, 24 m
3(=10 m
2 (floor area) * 2.4 m (height)) of the room in which an indoor device of the minimum
capacity is applied. The lower limit of the range is the value (0.009 kg/m
3) determined from the amount of refrigerant (for example, 0.4 kg) of the indoor device
with the minimum capacity, and the volume (for example, 30 m
3(=15 m
2 (floor area) ∗ 3.0 m (height)) of the room in which installation of the indoor device
is recommended. That is, if the need for a measure is "Error", this indicates the
presence of an erroneous detection or erroneous input in the numerical values acquired
by the acquisition devices 43 to 46. If it is determined that the calculated concentration
in the event of full leak is outside the range determined by the design conditions,
the determination device 47 displays Tables 3 and 4 on the display 4, and prompts
the worker to confirm whether the numerical value of each of the items is correct
and to correct the numerical values.
[0034] The air-conditioner design support device 1 having the above configuration reads
the data concerning the design drawing and outputs an indication of the need for a
safety measure with respect to refrigerant leak, according to a procedure described
below.
[0035] Fig. 4 is a flowchart of the procedure in the design support device 1 for outputting
an indication of the need for a safety measure with respect to refrigerant leak.
[0036] First, the read device 41 reads the image data of the design drawing 20 that have
been acquired by the image acquisition device 5 (S101). The constituent element recognition
device 42 recognizes, from the image data that have been read, the constituent elements
including the rooms, piping, ventilating fan, indoor devices, and outdoor devices
on the basis of the structure/shape and the like, and displays the result of recognition
on the display 4 (S102). Specifically, the drawing 21 depicted in Fig. 3, in which
the recognized constituent elements are diagrammatically represented, and Table 2,
described above, relating to the recognized constituent elements are displayed on
the display 4. The constituent element recognition device 42, if there has been an
input of correction/addition and the like from the worker, reflects the input result
in the drawing 21.
[0037] The dimension acquisition device 43 acquires the reference dimensions from the image
data that have been read, calculates the lengths of the sides of each of the rooms
11 to 14 and the floor areas thereof, and displays the calculated results on the display
4 (S103). If the reference dimensions cannot be acquired, the dimension acquisition
device 43 acquires the reference dimensions by displaying an input screen on the display
4 and having the worker input the reference dimensions.
[0038] The pipe diameter/pipe length acquisition device 44 acquires the pipe diameter and
pipe length of each of the pipes a to g from the image data that have been read, and
displays the acquired pipe diameters and pipe lengths on the display 4 (S104). If
some or all of the pipe diameters and pipe lengths cannot be acquired, the pipe diameter/pipe
length acquisition device 44 acquires the pipe diameters and pipe lengths by displaying
an input screen on the display 4 and having the worker input the pipe diameters and
pipe lengths.
[0039] The room height acquisition device 45 acquires the height of each of the rooms 11
to 14 from the image data that have been read, and displays the acquired height of
each of the rooms 11 to 14 on the display 4 (S105). If some or all of the heights
of the rooms 11 to 14 cannot be acquired, the room height acquisition device 45 acquires
the heights of the rooms 11 to 14 by displaying an input screen on the display 4 and
having the worker input the heights of the rooms 11 to 14.
[0040] The type/capacity acquisition device 46 acquires the type and capacity of the outdoor
device 200 and the indoor devices 101 to 104 from the image data that have been read,
and displays the acquired type and capacity of the outdoor device 200 and the indoor
devices 101 to 104 on the display 4 (S106). If some or all of the types and capacities
cannot be acquired, the type/capacity acquisition device 46 acquires the type/capacity
by displaying an input screen on the display 4 and having the worker input the type/capacity.
The type/capacity acquisition device 46 also calculates the amounts of refrigerant
on the basis of the acquired type and capacity, pipe diameter and pipe length, and
the amount of refrigerant and the additional amount of refrigerant stored in the refrigerant
amount storage device 32, and displays the results of calculation of the amounts of
refrigerant shown in Table 3 on the display 4.
[0041] The determination device 47, on the basis of the calculated amounts of refrigerant,
the height of each of the rooms 11 to 14, and the floor area of each of the rooms
11 to 14, determines (S107) the need for a safety measure with respect to refrigerant
leak on a room by room basis, and determines (S108) if there is a room for which a
safety measure is necessary. If there is a room for which a safety measure is necessary
(S108: YES), the determination device 47 determines (S109) whether there has been
an input of a safety measure from the worker with respect to the drawing 21 being
displayed on the display 4. If there has been an input from the worker (S109: YES),
the determination device 47 determines (S110) whether, due to the safety measure that
has been input, the concentration in the event of refrigerant leak in the room for
which the safety measure is necessary is smaller than the allowable concentration.
If there is no room for which a safety measure is necessary (S108: NO), or if the
concentration in the event of refrigerant leak is greater than or equal to the allowable
concentration (S110), the determination device 47 ends the process.
[0042] Thus, the air-conditioner design support device 1 is provided with: the read device
41 which reads data concerning the design drawing 20 for the air conditioner describing
the indoor devices 101 to 104, the outdoor device 200, the rooms 11 to 14, and the
pipes a to g; the acquisition devices 42 to 46 which acquire, from the data concerning
the design drawing 20 that have been read, data concerning the indoor devices 101
to 104, the outdoor device 200, the rooms 11 to 14, and the pipes a to g; and the
determination device 47 which calculates the amount of refrigerant required for the
air conditioner on the basis of the acquired data concerning the indoor devices 101
to 104, the outdoor device 200, and the pipes a to g, calculates the volume of each
of the rooms 11 to 14 on the basis of the acquired data concerning the rooms 11 to
14, determines the need for a safety measure with respect to each of the rooms 11
to 14 on the basis of the amounts of refrigerant and the respective volumes, and outputs
the determined results. With this configuration, it is possible to automatically and
easily determine the need for a safety measure with respect to the air conditioner.
[0043] If the data concerning the indoor devices 101 to 104, the outdoor device 200, the
rooms 11 to 14, or the pipes a to g cannot be acquired from the data concerning the
design drawing 20 that have been read, the acquisition devices 42 to 46 output a screen
for inputting the data. In this way, if there are data that cannot be acquired automatically,
the data can be acquired solely by means of a manual input operation. Accordingly,
the need for a safety measure with respect to an air conditioner can be determined
easily.
[0044] The determination device 47 calculates the refrigerant charge ratio in each of the
rooms 11 to 14 by dividing the amount of refrigerant by the respective volume, determines
whether the refrigerant charge ratio is within a predetermined range, and, if the
refrigerant charge ratio is not within the predetermined range, outputs information
indicating the presence of an error in data acquisition by the acquisition devices
42 to 46. In this way, it is possible to prevent determination of the need for a safety
measure on the basis of erroneous detection in the acquisition devices 42 to 46.
[0045] The determination device 47, if a safety measure with respect to the rooms 11 to
14 has been input, determines whether the safety measure is effective or not, on the
basis of the amount of refrigerant that leaks to the rooms 11 to 14 after the safety
measure is implemented, and the room volume. In this way, whether the safety measure
is effective or not can be determined easily.
[0046] The present invention is not limited to the foregoing embodiment. A person skilled
in the art will appreciate that various additions or modifications may be made within
the scope of the present invention.
[0047] For example, while in the foregoing embodiment, selection was made to install the
cut-off valve 400 in the room determined to require a safety measure, the mechanical
ventilation device 300 may be selected. When the mechanical ventilation device 300
is selected, a required amount of ventilation with respect to the room is calculated
automatically, and the installation position is also selected. In the room determined
to require a safety measure, a detector and an alarm may be installed in addition
to the mechanical ventilation device 300 and the cut-off valve 400. The data concerning
the design drawing 20 that are read by the read device 41 may include CAD data.
DESCRIPTION OF REFERENCE SIGNS
[0048]
- 1:
- Design support device
- 101 to 104:
- Indoor device
- 200:
- Outdoor device
- a to g:
- Pipes
- 11 to 14:
- Room
- 20:
- Design drawing
- 41:
- Read device
- 42:
- Element recognition device
- 43:
- Dimension acquisition device
- 44:
- Pipe diameter/pipe length acquisition device
- 45:
- Room height acquisition device
- 46:
- Type/capacity acquisition device
- 47:
- Determination device