JP3048856B2 - Heat exchanger temperature detector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature detector for a heat exchanger provided in a low-temperature showcase or the like.

[0002]

2. Description of the Related Art Conventionally, for example, as shown in Japanese Patent Publication No. 2-28782 (F25D11 / 00), a low-temperature showcase has a cooler (heat exchanger) which exchanges heat with a cooler (heat exchanger) in a refrigerator using a blower. Although the stored and cooled products are cooled by circulating, the frost grows on this cooler, so that the frost is heated by a defrost heater at a predetermined time or at a predetermined time interval to remove the defrost. . A defrost recovery sensor for terminating the defrost has conventionally been mounted on a cooler as shown in FIG.

That is, in FIG. 7, reference numeral 8 denotes a duct plate constituting a duct 12 inside a heat insulating box (not shown), and a horizontally long plate fin type cooler 17 is disposed in the duct 12. A fan 19 composed of a suction type propeller fan is mounted in a fan case 18 provided on the duct 8 side of the cooler 17.

The cooler 17 has a plurality of heat exchange fins 54.
· It is configured to penetrate a meandering refrigerant pipe 56,
Tube plates (not shown) are provided on both sides of the heat exchange fins 54, and the refrigerant pipes 56 are held by the tube plates. The refrigerant pipe 56 located outside the tube sheet is bent into a U-shape to form a bend portion 57, and the bend portion 57 has a cooler 17.
A defrost return sensor S for detecting the defrosting end temperature of the device is mounted. In this case, a temperature sensing cylinder 100 made of a copper pipe is fixed by welding to the bend portion 57 in advance, and the defrost recovery sensor S is inserted and held in the temperature sensing cylinder 100.

A defrost heater 53 is provided below the cooler 17.
Are provided to the left and right, and the inside of the duct 12 outside the tube sheet is closed by a partition plate 54 located on the cool air blowing side of the cooler 17. As a result, the air blown out of the blower 19 by the operation of the blower 19 passes through the heat exchange fins 54 of the cooler 17 and exchanges heat to be blown out. The cooler 17 is heated and defrosted by a defrost heater (not shown) at a predetermined time, for example, and the blower 19 is continuously operated during the defrost. Further, the defrost is configured to end when the temperature detected by the defrost recovery sensor S rises to, for example, + 12 ° C.

[0006]

However, as described above, in the related art, the bend portion 57 of the refrigerant pipe 56 of the cooler 17 is conventionally used.
Since the defrost recovery sensor S is attached to the
Temperature could not be accurately detected, causing various problems. That is, in the related art, due to the presence of the partition plate 54, the wind (cool air) from the blower 19 around the defrost recovery sensor S during defrosting.
Does not flow. Therefore, the temperature detected by the defrost recovery sensor S is likely to increase, and the defrost ends even though frost remains between the heat exchange fins. In particular, when outside air has entered and frost has temporarily increased, such frost residue has been remarkably generated.

If the above defrosting end temperature (+ 12 ° C.) is set higher to solve this problem, the defrosting time is unnecessarily prolonged, the temperature of the product rises abnormally, and ice cream and the like melt. Problems arise.

Therefore, for example, in Japanese Utility Model Laid-Open No. 3-127188 (F25D29 / 00), a sensor is provided between heat exchange fins by using a mounting device in which both ends are curved and respectively engaged with refrigerant pipes (adjacent refrigerant pipes). However, in the case of such a mounting device, the sensor is located between the outermost refrigerant pipes and disposed outside of them, so it is still difficult to sense the temperature of the heat exchanger, There was a problem that the remaining occurrence could not be effectively eliminated.

The present invention has been made to solve the above-mentioned conventional technical problem, and has as its object to provide a temperature detecting device capable of accurately detecting the temperature of a heat exchanger such as a cooler. And

[0010]

The temperature detecting device of the present invention is used in a heat exchanger in which a plurality of heat exchange fins penetrate a meandering refrigerant pipe, and detects a temperature of the heat exchanger. And a heat-conductive sensor mount for attaching the sensor to the heat exchanger. This sensor mount holds the sensor on one surface and the other surface corresponds to a refrigerant pipe located between the heat exchange fins. A first holding portion which is in contact with the first end of the holding portion and which engages with a refrigerant pipe located on one surface of the holding portion;
And a second engaging portion that is continuous with the other end of the holding portion and engages with a corner of the heat exchanger located on the other surface side of the holding portion.

[0011]

According to the temperature detecting device of the heat exchanger of the present invention, the sensor is held on one surface of the holding portion of the sensor mounting member whose other surface is in contact with the refrigerant pipe between the heat exchange fins. It becomes possible to detect the temperature of the refrigerant pipe on the back side immediately after transmitting the holding unit having good thermal conductivity. Therefore, it is possible to accurately detect the temperature of the heat exchanger and smoothly and accurately execute control based on the temperature. When the present invention is applied to a cooler, generation of frost residue and unnecessary use of defrosting time are possible. An increase in product temperature due to extension can be avoided beforehand.

In particular, a first engaging portion connected to one end of the holding portion is engaged with a refrigerant pipe located on one surface side of the holding portion, and a second engaging portion connected to the other end of the holding portion is held. The sensor attachment is attached to the heat exchanger by engaging with the corner of the heat exchanger located on the other side of the part, so the sensor is attached more inward than the outermost refrigerant pipe This makes it possible to further improve the temperature detection performance and to easily and surely attach the sensor to the heat exchanger, so that reliability and assembly workability can be significantly improved. Things.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view of a low-temperature showcase 1 as an embodiment to which the present invention is applied, FIG. 2 is a vertical sectional side view of the low-temperature showcase 1, and FIG. 4 is an enlarged vertical sectional side view of the cooler 17 of the low-temperature showcase 1. In each figure, the same reference numerals as those in FIG. 7 denote the same elements.

The low-temperature showcase 1 is used for displaying and preserving ice cream or the like in a convenience store or the like, and comprises a horizontally long rectangular heat insulating box 2 opened upward. This heat insulation box 2
Is a metal outer box 3, a metal inner box 6 incorporated in the outer box 3 at intervals, and a foamed polyurethane filled between the two boxes 3, 6 by an in-situ foaming method. And the heat insulating material 7.

Duct plates 8 and 9 are attached to the inside of the front and rear surfaces of the inner box 6 at intervals.
A bottom plate 11 called a deck pan is detachably mounted between lower ends of the inner box 6, thereby forming a series of ducts 12 rising up and down from the bottom inside the inner box 6. And storage room 2 inside bottom plate 11
2 (FIG. 3 shows the bottom plate 11 removed). On the other hand, the bottom wall 13 of the heat insulating box 2 has a stepped shape having a lower portion 13A at a front portion and a higher portion 13B at a rear portion, and the bottom plate 11 is located above the higher portion 13B.

A drain pan 14 is formed on the upper surface of the lower portion 13A. A drain hole 16 is formed at the lowest position of the drain pan 14 and communicates with the outside of the heat-insulating box 2 below. On the drain pan 14, the duct 12
A horizontally long plate-fin type cooler 17 as a heat exchanger is disposed in the inside, and a blower 19 composed of a suction type propeller fan is mounted in a fan case 18 provided in front of the cooler 17. ing.

A high-order portion 13B on the rear side of the cooler 17
The stepped portion of the lower portion 13A has an inclined surface 13C such that the upper portion is separated from the cooler 17. The upper end of the duct plate 9 is a discharge port 9A, the upper end of the duct plate 8 is a suction port 8A, and wind direction plates 21, 21 which are curved inward are attached to the discharge port 9A at predetermined intervals.

On the other hand, on both sides of the opening of the heat-insulating box 2, side plates 41, 41 made of a transparent acrylic resin thick plate are erected. The side plates 41, 41 have a substantially mountain shape that is inclined such that the upper portions of the front and rear sides 41A, 41B are close to each other, and a stainless steel top plate 42 is also provided between the upper end portions thereof. It is screwed from the side via 43.

The top plate 42 has a mountain-shaped cross section along the shape of the upper portions of the side plates 41, 41. The lower surface of the top plate 42 is formed of a stainless steel reflecting plate via front and rear stainless steel upper support plates 44, 44. A plate 46 is attached. The upper support plates 44, 44 have a predetermined distance from the lower surface of the top plate 42, and the tips thereof are inclined downward downward substantially along the inclination of the front and rear sides 41A, 41B of the side plate 41, respectively. A horizontally long fluorescent lamp 51 is housed and arranged on the lower surface of the reflection plate 46, and a stabilizer 52 for lighting the fluorescent lamp 51 is arranged on the upper surface.

On the other hand, rails 63, 63 are attached to the front and rear opening edges of the heat-insulating box 2 across the left and right. Between the rails 63, 63 and the top plate 42, the storage room 22 of the low-temperature showcase 1 is Open in the front-rear direction (opening 64, 6
4) Yes. With this configuration, the upper edges of the front and rear openings 64, 64 of the storage room 22 of the low-temperature showcase 1 are located deeper than the lower edge and open diagonally upward, and the rails 63, 63 are located below these openings 64, 64. The front and rear side surfaces of the upper support plates 44, 44 and the reflection plate 46 are located at the edges.
Will be located at the upper edge.

On the rail 63, a plurality of sliding doors 73 made of, for example, a transparent acrylic resin plate or a transparent glass are slidably mounted and supported. In this case, in the embodiment, eight doors 7 are arranged in front and rear of each of the two doors.
3 is supported, the upper part of the door 73 supported inside is supported by the front and rear side surfaces of the reflection plate 46, and the upper part of the door 73 supported outside is supported by the upper support plate 44.

At the front and rear ends of the heat-insulating box 2, kick plates 26, 26 having a large number of through holes 24 are attached, and the heat-insulating box 2 is located between the kick plates 26, 26. A machine room 27 is formed below. A compressor (not shown), a condenser 29, and a blower 31 for the condenser, which constitute a well-known refrigeration cycle together with the cooler 17, are disposed in the machine room 27 located below the high-order portion 13B. At the same time, the rear surface of the machine room 27 is closed and opened by a plurality of panels 36 to 38 so that the compressor is located on the panel 38 and the condenser 29 is located on the rear side of the panel 37. The panels 37 and 38 have slits 3 respectively.
9 ... are formed in plurality.

Here, the cooler 17 is formed by penetrating a plurality of heat exchange fins 54 through a meandering refrigerant pipe 56, and tube plates 61 are provided on both sides of the heat exchange fins 54. The refrigerant pipe 56 is held by a tube sheet 61, and the refrigerant pipe 56 located outside the tube sheet 61 is bent into a U-shape to form a bend portion 57. Further, a lower bracket 62 is attached to a lower corner of the cooler 17 on the inclined surface 13C side.

A defrost heater 53 is provided below the cooler 17.
Are provided to the left and right, and the inside of the duct 12 outside the tube sheet 61 is closed by a partition plate 54 located on the inclined surface 13C side of the cooler 17. As a result, the air blown out of the blower 19 by the operation of the blower 19 passes through the heat exchange fins 54 of the cooler 17 between the tube sheets 61, 61 and exchanges heat to be blown out. .

The cooler 17 is provided with a defrosting recovery sensor S composed of a thermistor from the inclined surface 13C side, and a sensor mounting member 81.
Attached by The sensor mounting member 81 is made of a thermally conductive plate material such as aluminum, and has a holding portion 82 as shown in FIG.
The pressing sides 83, 83 standing on one surface (upper surface) side and the first engaging portion 84 continuously bent obliquely upward (one surface side of the holding portion 82) from one end (tip) of the holding portion 82. When,
Continuously from the other end (base) of the holding portion 82 and downward (holding portion 8
2 and a second engaging portion 86 whose lower end is bent at a right angle in the direction in which the holding portion 82 extends.

The defrosting return sensor S is a sensor attachment 81
5 is inserted into one surface (upper surface) of the holding portion 82, and the holding sides 83, 83 on both sides are placed inside (the holding portion 82) as shown by arrows in FIG.
Side). Note that reference numeral 87 denotes silicon for preventing the sensor S from coming off, and L denotes a lead wire. The sensor attachment 81 holding the sensor S in this manner
Is inserted between the heat exchange fins 54, 54 located at the central portion on the inclined surface 13C side of the cooler 17, as shown in FIGS. Then, the lower surface (other surface) of the holding portion 82 is connected to the refrigerant pipe 5.
6 and a first engaging portion 84 at one end thereof.
Is brought into contact with the lower surface of the refrigerant pipe 56 located on the inner side of the refrigerant pipe 56 (on the upper surface (one surface) side of the holding portion 82). Further, the second heat transfer fin 54 is located outside the heat exchange fin 54.
Is engaged with the outer surface of the lower bracket 62, and the sensor mounting member 81 is mounted on the cooler 17.

As described above, the first engaging portion 84 connected to one end of the holding portion 82 holding the defrost recovery sensor S is engaged with the refrigerant pipe 56 located on the upper surface (one surface) of the holding portion 82. The second mounting portion 86 connected to the other end of the holding portion 82 is engaged with the lower metal fitting 62 at the corner of the cooler 17 located below (on the other side of) the holding portion 82 to thereby attach the sensor mounting member. 81
Is attached to the cooler 17, so that the defrost recovery sensor S can be easily and reliably attached to the cooler 17, and reliability and assembly workability can be significantly improved. .

Next, the operation will be described with reference to the timing chart of FIG. The compressor and the blowers 19, 3
When 1 is operated, the cool air cooled by the cooler 17 is blown backward in the duct 12 from the inclined surface 13C, and is discharged from the discharge port 9A at the upper end of the duct plate 9 toward the upper part of the storage room 22. . The cool air circulated in the storage room 22 is sucked into the duct 12 from the suction port 8A at the upper end of the duct plate 8,
Circulation (indicated by a dashed arrow in FIG. 2) for returning to the blower 19 is performed.

For example, -20 ° C. is set as a set temperature in a control device (not shown). For example, the compressor is operated (ON) at −20 ° C. based on the temperature of the suctioned cool air of the cooler 17, and For example, the compressor is stopped (OFF) at a lower limit temperature such as −22 ° C. The blower 19 and the condenser blower 31 are continuously operated. by this,
The inside of the storage room 22 is cooled to the above-mentioned -20 ° C freezing temperature.

With this cooling operation, frost grows on the cooler 17. For example, at 8:00 am or 8:00 pm every 12 hours, the control device stops the compressor and causes the defrost heater 53 to operate. Electric power is supplied to generate heat, and a frost lamp (not shown) is turned on to start defrosting of the cooler 17. still,
Since the blower 19 and the condenser blower 31 are continuously operated during the defrosting, the cool air is circulated around the defrosting return sensor S as in the other coolers 17.

The heat generated by the defrost heater 53 causes the cooler 1
7 is heated and the frost is gradually melted. At this time, the defrost water dropped from the cooler 17 is collected on the drain pan 14 and discharged from the drain hole 16. Then, when the temperature detected by the defrost recovery sensor S rises to + 12 ° C., the control device stops the energization of the defrost heater 53 and the frost lamp, enters a draining operation for 5 minutes, and after the draining is completed, again performs the cooling. Return to operation.

At this time, in the present invention, the defrost recovery sensor S is held on the upper surface (one surface) of the holding portion 82 of the sensor mounting member 81 whose lower surface (other surface) is in contact with the refrigerant pipe 56 between the heat exchange fins 54, 54. Therefore, the defrost return sensor S is disposed between the heat exchange fins 54, 54, and the defrost return sensor S
Can detect the temperature of the refrigerant pipe 56 which is conducted through the sensor mounting member 81 having good thermal conductivity. Therefore, it is possible to accurately detect the defrost return temperature of the cooler 17, and it is possible to prevent a rise in product temperature due to generation of frost residue and unnecessary extension of the defrost time. .

In the embodiment, the cooler 17 is used as a heat exchanger.
However, the present invention may be applied to the condenser 29 or the like to control the condenser blower 31 or the like. In the embodiment, the present invention is applied to a low-temperature showcase. However, the present invention is not limited to this, and the present invention is effective for refrigerators, air conditioners, ice makers, and other various devices.

[0034]

As described above in detail, according to the present invention, the sensor is held on one surface of the holding portion of the sensor mounting member whose other surface is in contact with the refrigerant pipe between the heat exchange fins. It becomes possible to detect the temperature of the refrigerant pipe on the rear side immediately after transmitting the good-conductivity holding section. Therefore,
It is possible to accurately detect the temperature of the heat exchanger and perform control based on it accurately and smoothly, and when it is applied to a cooler, due to generation of frost residue and unnecessary extension of defrost time It is possible to avoid a rise in product temperature before it occurs.

In particular, the first engaging portion connected to one end of the holding portion is engaged with the refrigerant pipe located on one side of the holding portion, and the second engaging portion connected to the other end of the holding portion is held. The sensor attachment is attached to the heat exchanger by engaging with the corner of the heat exchanger located on the other side of the part, so the sensor is attached more inward than the outermost refrigerant pipe This makes it possible to further improve the temperature detection performance and to easily and surely attach the sensor to the heat exchanger, so that reliability and assembly workability can be significantly improved. Things.

[Brief description of the drawings]

FIG. 1 is a perspective view of a low-temperature showcase to which the present invention is applied.

FIG. 2 is a vertical side view of a low-temperature showcase to which the present invention is applied.

FIG. 3 is an overhead perspective view of a cooler portion of a low-temperature showcase to which the present invention is applied.

FIG. 4 is an enlarged vertical sectional side view of a cooler portion of a low-temperature showcase to which the present invention is applied.

FIG. 5 is a perspective view of a defrosting return sensor and a sensor attachment.

FIG. 6 is a timing chart for explaining the operation of the low-temperature showcase to which the present invention is applied.

FIG. 7 is an overhead perspective view of a cooler portion of a conventional low-temperature showcase.

[Description of Signs] 1 Low-temperature showcase 2 Insulated box 17 Cooler (heat exchanger) 19 Blower 54 Heat exchange fin 56 Refrigerant piping 81 Sensor mounting 82 Holding section 84 First engagement section 86 Second engagement Part S Defrosting recovery sensor (sensor)

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toyosaku Hamada 2-5-5, Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (56) References Really open 3-127188 (JP, U) Hei 2-96575 (JP, U) Japanese Utility Model Showa 63-110863 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F25D 29/00 F25B 49/02 510

Claims (1)

(57) [Claims] 1. A heat exchanger comprising a plurality of heat exchange fins penetrating a meandering refrigerant pipe, a sensor for detecting a temperature of the heat exchanger, and a heat exchanger for attaching the sensor to the heat exchanger. A holding part for holding the sensor on one surface and abutting a refrigerant pipe located on the other surface between the heat exchange fins, and one end of the holding part. And a first engagement portion that engages with the refrigerant pipe located on the one surface side of the holding portion, and a heat exchange that is continuous with the other end of the holding portion and located on the other surface side of the holding portion. And a second engaging portion that engages with a corner of the heat exchanger.