JPS6347783Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a forced convection oven, and in particular to one in which the hot air sucked in and exhausted from the roasting chamber by a fan is reheated by a heater and introduced into the roasting chamber from both sides. This invention relates to a forced convection oven that introduces hot air not only from the innermost part of the roasting chamber but also from the front side of the door so that an object to be heated, such as sweet bread on a baking pan, can be roasted uniformly without unevenness.

Various types of ovens have been proposed in the past, but in each type, inside the roasting chamber,
There was a drawback that a temperature distribution occurred where the temperature was extremely high in the inner part near the suction/exhaust type fan, leading to roasting spots.

Therefore, the present applicant has already proposed a device as disclosed in Japanese Utility Model Application Publication No. 130102/1983 to solve this problem. As shown in FIG. 1, this invention includes a suction/exhaust fan 3 attached to the rear of the roasting chamber 1 via a baffle plate 2, and heaters 4, such as infrared electric heaters, installed on both sides of the roasting chamber 1. The air sent into the duct 5 from the fan 3 is heated by the heater 4, and then roasted through a large number of gaps 11 formed on each side wall of the roasting chamber 1. Hot air is introduced into the chamber 1 and the object to be heated on the baking pan 6 is roasted, and the hot air inside the roasting chamber 1 is sucked and exhausted through the suction and exhaust holes 7 of the baffle plate 2 by a fan, and thereafter, inside the duct 5. It has been reintroduced into circulation. However, since the hot air is introduced into the roasting chamber 1 only from both sides, the innermost center of the roasting chamber 1 and the front center of the door 8 are shown as the hatched area 9 shown by the two-dot chain line. The temperature of the part marked 9 is lower than other parts,
As a result, there was a drawback that roasting spots occurred.
Moreover, since the gap 11 is constant from the inner back of the roasting chamber 1 to the front side, the wind pressure passing through the gap at the inner back is closer to the fan 3 than at the front side. Because of this, the shaded area 9
Even in other places, there was a problem that some roasting spots were caused.

Therefore, in view of the above-mentioned circumstances, the present invention aims to achieve uniform roasting without unevenness by sending hot air into the roasting chamber not only from both sides but also from the inner depths and front side. In order to achieve this, in a forced convection oven in which the hot air inside the roasting chamber that is sucked and exhausted by a fan is reheated by a heater and introduced into the roasting chamber from both sides, A duct is provided on the front side facing the
The duct at the back of the roasting chamber communicates the air blowing side of the fan with the inner back of the roasting chamber, and the duct at the front communicates between the ducts on both sides of the roasting chamber and the front side of the roasting chamber. The purpose of this invention is to provide a forced convection oven with the following characteristics.

An embodiment of the forced convection oven according to the present invention will be described below with reference to the drawings. In FIGS. 2 to 5, 12 is an outer case, 13 is an inner case, and 14 is an outer case.
is a door that can be opened and closed. Both sides of the inner case 13,
A heat insulating material 15 is attached to the top, rear and bottom. Inside the inner case 13, four pillars 16 are set up at the back and in front of the door 14, and a channel steel 17 creates an appropriate gap 18 between the pillars 16 facing each other at the back and the front. A suitable number of such structures are suspended horizontally in the height direction. A gap 45 is also formed in the longitudinal direction approximately at the center of the channel steel 17. Each gap 18,
The width of 45 is different for each stage in the height direction, for example, the gap 18, 45 between the bottom and top stages.
The gaps 18, 45 are generally slightly wider than the central gaps 18, 45, and except for the uppermost and lowermost gaps 18, 45, the front side is slightly narrower than the innermost part. The amount of air passing through 45 is adjusted in accordance with temperature etc. so that the degree of roasting becomes uniform. A baffle plate 19 having a U-shaped cross section is fixed to the pillar 16 at the innermost part, and this baffle plate 1
A suction/discharge hole 20 is formed in the center of 9. A space surrounded by each channel steel 17 and the baffle plate 19 is a roasting chamber 21, and a duct 22 is formed with an appropriate gap between each channel steel 17 and the side wall of the inner case 13. ing. Each channel steel 17 is supported by a top pan 23 with a lower flange as shown in FIG.
are arranged in several stages, and the upper flange is inclined diagonally upward so that the hot air passing through the gap 18 is directed toward the bottom of the baking pan 23. ing. Further, the hot air passing through the gap 45 is blown out toward the upper surface of the baking pan 23. Inside each duct 22, heaters 24 such as infrared electric heaters are arranged in several stages in the height direction. On the other hand, a suction/exhaust type fan 25 is installed between the baffle plate 19 and the rear wall of the inner case 13 so as to face the suction/exhaust hole 20 . The fan 25 is connected to a drive motor 28 via a pulley 26 and a belt 27, and is driven to rotate.
The drive motor 28 is installed between the outer case 12 and the inner case 13. A duct 31 is attached to the baffle plate 19 so as to be located on the surface on the roasting chamber 21 side, with an appropriate gap 30 in between via a spacer 29 . The duct 31 is as shown in FIGS. 6 and 7.
It has a substrate 32 fixed to the baffle plate 19 with screws or the like, and a cylindrical body 33 is fixed to one surface of this substrate 32,
Both upper and lower ends of this cylinder 33 extend from both upper and lower ends of the substrate 32 to face the other side, forming openings 34 and 35. Each opening 34, 35 is
It is located at the discharge portion where the wind pressure is high due to the fan 25 and communicates with discharge ports 36 and 37 formed in the baffle plate 19. The cylindrical body 33 has a slit 3 for blowing out.
8 is formed, and this slit 38 is located at the center of the innermost part of the roasting chamber 21. A space between the baffle plate 19 in which the fan 25 is installed and the rear wall of the inner case 13 communicates with ducts 22 located on both sides of the roasting chamber 21. Duct 22
An opening 39 is formed at the end on the door 14 side. Furthermore, a duct 40 is formed on the inner surface of the door 14. This duct 40 is formed into a housing shape,
Both sides have openings 41 that communicate with the opening 39 when the door 14 is closed, and a slit 42 for blowing air is formed in the inner wall. This slit 42 is located at the center of the front side of the roasting chamber 21 when the door 14 is closed. The duct 40 is made of heat-resistant glass so that the central part of the door 14 and the central part near the slit 42 can be seen through. It goes without saying that the door 14 closes the front opening end of the roasting chamber 21. A control device and an operation panel 43 are mounted in the front space between the outer case 12 and the inner case 13.

In the oven configured as described above, when the suction/exhaust type fan 25 is first rotated by the drive motor 28, the air in the roasting chamber 21 is pumped into the gap between the duct 31 and the baffle plate 19, as shown by the small broken arrow in FIG. 30 and the suction/exhaust hole 20 into the space between the baffle plate 19 and the inner case 13, and then fed into the duct 22 as shown by the large white arrow in FIG. 24 and becomes hot air, which is introduced into the roasting chamber 21 through the gaps 18 and 45, and after roasting the object to be heated such as sweet bread placed on the baking pan 23, it is again passed through the gap 30 and the suction/exhaust hole 20.
After that, it is sucked in and discharged between the baffle plate 19 and the inner case 13, and thereafter the above-mentioned circulation is repeated. Since the width of the gap 18 is adjusted in advance as described above,
The amount of air blown into the roasting chamber 21 from each gap 18, 45 is adjusted according to various conditions such as the air temperature at each part. The volume and pressure of this hot air vary depending on the direction of rotation of the fan 25. For example, when the fan 25 rotates in the normal direction, the wind pressure at the innermost part of the left duct 22 and the front side of the right duct 22 shown in FIG. becomes small, and in reverse rotation, the wind pressure at the innermost part of the right duct 22 and the front side of the left duct 22 becomes small. By switching from reverse rotation and further from reverse rotation to forward rotation, unevenness in wind pressure or air volume within the duct 22 is totally absorbed. On the other hand, hot air is also sent into the duct 31 from between the baffle plate 19 in which the fan 25 is installed and the inner case 13 through the discharge ports 35 and 36 and the openings 34 and 35.
1 is blown out through the slit 38 to the center of the innermost part of the roasting chamber 21, and the object to be heated in this vicinity is roasted. In this case, a heater may also be installed inside the duct 31 to heat the air blown out from the slit 38 to the center of the inner depth of the roasting chamber 21.
Furthermore, the hot air in the duct 22 is also introduced into the duct 40 through the openings 39 and 41, and is blown out from the duct 40 through the slit 42 to the center of the front side of the roasting chamber 21, and is blown out to the center of the front side of the roasting chamber 21. Roast heated foods.

The temperature inside the roasting chamber 21 is detected by a thermostat or the like, and the heater 24 is operated to maintain the temperature at a set temperature.
energization is controlled.

In addition, in the present invention, depending on the roasting conditions, the roasting chamber 21
A humidifier can also be installed to add moisture to the atmosphere inside.

As described above, according to the forced convection oven of the present invention, the hot air in the roasting chamber sucked and exhausted by the conventional fan is reheated by the heater and introduced into the roasting chamber from both sides. The inner part of the roasting chamber and the center part on the front side facing this inner part are lower in temperature than other parts, which effectively prevents defects such as roasting spots and produces high quality products. This method has many other practical effects, such as being able to obtain a product with a simple configuration of only providing ducts at the inner back and front side of the roasting chamber.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view showing the main parts of a conventional forced convection oven, Fig. 2 is a partially cutaway perspective view showing an embodiment of the forced convection oven according to the present invention, and Fig. 3 shows the door. Fig. 4 is a sectional view taken along the - line in Fig. 1 in the closed state, Fig. 5 is a sectional view taken along the - line in Fig.
The figure is a cross-sectional view of Figure 1 with the door closed.
6 and 7 are perspective views of the duct. 12... Outer case, 13... Inner case, 14...
...door, 15...insulation material, 16...post, 17...
Channel steel, 18, 30, 45... Gap, 19... Baffle plate, 20... Suction/exhaust hole, 21... Roasting chamber, 22,
31,40...Duct, 23...Tenpan, 24...
... Heater, 25 ... Suction and exhaust type fan, 26 ... Pulley, 27 ... Belt, 28 ... Drive motor, 29
...Spacer, 32...Substrate, 33...Cylinder, 3
4, 35, 39, 41... opening, 36, 37...
Discharge port, 38, 42... slit, 43... operation panel.

Claims (1)

[Scope of utility model registration request] In a forced convection oven in which the hot air in the roasting chamber that is sucked and exhausted by a fan is reheated by a heater and introduced into the roasting chamber from both sides, the innermost part of the roasting chamber and the innermost part of the roasting chamber are opposite to each other. A duct is provided on each side of the roasting chamber, and the duct at the inner back communicates the air blowing side of the fan with the inner back of the roasting chamber, and the duct at the front communicates with the ducts on both sides of the roasting chamber. A forced convection oven characterized by communicating with the front side of the oven.