A hot air circulating oven
By designing a rotatable heating resistance wire and a sliding head structure in the hot air circulating oven, the problem of fixed heating power of the resistance wire is solved, enabling flexible adjustment of heat and improving heating efficiency and temperature control flexibility.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HENAN SANDWICH FOOD CO LTD
- Filing Date
- 2024-11-29
- Publication Date
- 2026-05-19
AI Technical Summary
In existing hot air circulating ovens, the heating power of the resistance wire is fixed during the heating process, which means that it takes a long time or frequent power outages to reach the set temperature, resulting in heat loss and making it impossible to achieve flexible heat adjustment.
By designing a rotatable heating resistance wire and a sliding head structure, the position of the heating resistance wire inside the fan casing is changed by using the fan impeller to adjust the heat carried by the airflow, thus achieving flexible heat adjustment.
It enables heat adjustment in hot air circulating ovens, reduces energy consumption, and improves heating efficiency and temperature control flexibility.
Smart Images
Figure CN119404865B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to food baking equipment, and more particularly to a hot air circulating oven. Background Technology
[0002] An oven is a common food baking equipment. It consists of a chamber containing a temperature sensor and an electrically powered heating resistance wire. To ensure that the heat is distributed more evenly within the chamber, an oven usually also has a circulating fan.
[0003] When in use, the resistance wire is energized to generate heat, and the circulating fan circulates this heat throughout the entire oven, thus baking and heating the food inside evenly. The problem with existing hot air circulating ovens is that when the oven's heating temperature is set, the resistance wire is de-energized once that temperature is reached, and then re-energized when the temperature drops below that point.
[0004] In existing technologies, the heating power of the resistance wire for each signal is fixed. To change the heating power, the only method is to add or remove working resistance wires, resulting in a large adjustment range. The heating power of the resistance wire after being energized is constant and cannot be adjusted. For low-power ovens, reaching the set heating temperature takes a long time. For high-power ovens, once the set heating temperature is reached, the resistance wire is de-energized and cools down. When the temperature drops below the set temperature, the resistance wire is energized again. Due to the high heating power of the resistance wire, the oven quickly reaches the set temperature. Therefore, during the entire heating process, the resistance wire is frequently de-energized and energized, resulting in significant heat loss. Summary of the Invention
[0005] The purpose of this invention is to provide a hot air circulating oven with adjustable circulating air heat.
[0006] To solve the above-mentioned technical problems, the technical solution of the hot air circulating oven with adjustable circulating heat in this invention is as follows:
[0007] A hot air circulating oven includes a housing, inside which a circulating fan, a temperature sensor, and an electrically powered heating resistance wire are installed. The circulating fan includes a vertically arranged fan cylinder and a fan impeller with its rotation axis extending vertically along the inner side of the fan cylinder. The fan cylinder is a square cylinder. A rotating bracket is rotatably mounted on the upper side of the fan cylinder on the housing. The rotating bracket is driven by a first motor and is coaxial with the fan impeller. A heating resistance wire with its axis horizontally arranged is installed on the rotating bracket. The axial length of the heating resistance wire is not less than the diagonal length of the fan cylinder. As the rotating bracket rotates with the heating resistance wire, the length of the vertical projection of the heating resistance wire on the fan cylinder changes.
[0008] Furthermore, the rotating bracket includes a first vertical arm and a second vertical arm symmetrically arranged with the rotation axis of the rotating bracket as the center line of symmetry. One end of the heating resistance wire is fixed on the first vertical arm, and the other end of the heating resistance wire is fixed on the second vertical arm.
[0009] Furthermore, the rotating bracket also includes a vertically arranged bracket shaft, with a horizontal connecting arm at the bottom of the bracket shaft. The horizontal connecting arm has a connecting arm ventilation hole that runs through the horizontal connecting arm in the vertical direction. The first vertical arm and the second vertical arm are fixed to both ends of the connecting arm.
[0010] Furthermore, a guide rod is fixed between the first vertical arm and the second vertical arm, with the guide direction aligned with the axis of the heating resistance wire. The guide rod is equipped with a first sliding head and a second sliding head that can move relative to or in opposite directions. The upper end of the first sliding head is in contact with the heating resistance wire and is electrically connected. The upper end of the second sliding head is in contact with the heating resistance wire and is electrically connected. The first sliding head and the second sliding head are connected in series in the heating power supply circuit of the heating resistance wire and are driven by a sliding head driving mechanism.
[0011] Furthermore, the sliding head drive mechanism includes a fixed shaft fixed to the upper end of the fan casing via a fixed shaft bracket. The fixed shaft is coaxial with the fan impeller. The fixed shaft bracket is provided with a bracket ventilation channel extending in the vertical direction. A first steel wire rope connected to the first sliding head and a second steel wire rope connected to the second sliding head are wound around the upper end of the fixed shaft. A sliding head return spring is provided between the first sliding head and the second sliding head.
[0012] Furthermore, the inner cavity of the box is divided into a fan chamber and a baking chamber arranged on the left and right by a partition. The upper end of the partition is provided with a fan chamber air inlet connecting the fan chamber and the baking chamber, and the lower end of the partition is provided with a fan chamber air outlet connecting the fan chamber and the baking chamber. The circulating fan and the heating resistance wire are located in the fan chamber.
[0013] Furthermore, an equipment compartment is provided at the upper end of the housing, a first motor is located in the equipment compartment, a second motor is also located in the equipment compartment, and a baking rack shaft with a rotating axis extending in the vertical direction is mounted in the baking chamber. The upper end of the baking rack shaft extends into the equipment compartment and is connected to the second motor for transmission.
[0014] The beneficial effects of this invention are as follows: In this invention, the fan impeller rotates, generating a downward airflow within the inner cavity of the fan casing. The airflow velocity outside the fan casing cross-section is relatively low. In this invention, the rotating bracket drives the heating resistance wire to rotate, thereby changing the heat carried by the airflow. Specifically, when the axial length of the heating resistance wire is aligned with the diagonal of the fan casing, the vertical projection length of the heating resistance wire on the fan casing is the longest. At this time, the airflow can carry more heat generated by the heating resistance wire for circulation. When the axial length of the heating resistance wire is aligned with the short side length of the fan casing, the vertical projection length of the heating resistance wire on the fan casing is the shortest. The effective heat generated by the heating resistance wire outside the fan casing cross-section cannot be carried away by the airflow. At this time, the airflow can carry less heat generated by the heating resistance wire for circulation, thereby achieving adjustment of the circulating air heat. Attached Figure Description
[0015] The above and other objects, features, and advantages of this disclosure will become readily apparent from the following detailed description of exemplary embodiments with reference to the accompanying drawings. In the drawings, several embodiments of this disclosure are illustrated by way of example and not limitation, and like or corresponding reference numerals denote like or corresponding portions, wherein:
[0016] Figure 1 This is a schematic diagram of the structure of one embodiment of the present invention;
[0017] Figure 2 yes Figure 1 Enlarged view of point A in the image;
[0018] Figure 3 yes Figure 1 In the diagram, viewed from below, it shows the interaction between the fixed shaft and the first and second sliding heads.
[0019] Figure 4 This is a schematic diagram of the first state of the heating resistance wire and the fan cylinder in this invention;
[0020] Figure 5 This is a schematic diagram of the second state of the heating resistance wire and the fan cylinder in this invention;
[0021] Figure 6 This is a schematic diagram of the third state in which the heating resistance wire and the fan casing are combined in this invention;
[0022] 1. Support shaft; 2. Horizontal connecting arm; 3. First vertical arm; 4. Heating resistance wire; 5. First sliding head; 6. Fixed shaft support; 7. Fan casing; 8. Connecting arm ventilation hole; 9. Fan chamber air inlet; 10. Second vertical arm; 11. Partition plate; 12. Fixed shaft; 13. Fan impeller; 14. Support shaft; 15. First motor; 16. Second motor; 17. Baking rack shaft; 18. Equipment interlayer; 19. Fan chamber air outlet; 20. Box body; 21. Baking rack; 22. Fan chamber; 23. Baking chamber; 24. Guide rod; 25. Second sliding head; 26. Return spring; 27. First steel wire rope; 28. Second steel wire rope. Detailed Implementation
[0023] To facilitate understanding of the present invention, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.
[0024] It should be noted that, unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the invention.
[0025] An embodiment of a hot air circulating oven in this invention is as follows: Figures 1-6 As shown:
[0026] The enclosure includes a housing 20, the inner cavity of which is divided by a partition 11 into a fan chamber 22 and a baking chamber 23 arranged on the left and right sides. The upper end of the partition is provided with an air inlet 9 for the fan chamber, and the lower end of the partition is provided with an air outlet 19 for the fan chamber. The baking chamber 23 is equipped with a temperature sensor and a baking rack 21, and the fan chamber is equipped with a circulating fan and a heating resistance wire 4.
[0027] The upper end of the housing is provided with an equipment interlayer 18, and the baking rack is set on the baking rack shaft 17. The axis of the baking rack shaft 17 extends in the vertical direction. The upper and lower ends of the baking rack shaft 17 are rotatably engaged with the upper and lower ends of the baking chamber. The equipment interlayer 18 can be equipped with a first motor 15 and a second motor 16. The upper end of the baking rack shaft 17 extends into the equipment interlayer and is connected to the second motor 16 for transmission. Specifically, the upper end of the baking rack shaft is connected to the motor shaft of the second motor through a transmission chain.
[0028] The circulating fan includes a vertically arranged fan casing 7. The outer periphery of the fan casing 7 is fixed to the inner wall of the fan chamber by a fan casing bracket. The fan casing is a square tube. In this embodiment, the inner cross-section of the fan casing is rectangular. The long side of the fan casing extends in the left-right direction, and the short side of the fan casing extends in the front-back direction. The circulating fan also includes a fan impeller 13 disposed inside the fan casing, with its rotation axis extending in the up-down direction. When the fan impeller 13 rotates, it generates a downward airflow.
[0029] A rotating bracket is rotatably mounted on the upper side of the fan casing. The rotating bracket is driven by the first motor 15. The rotation axis of the rotating bracket is set coaxially with the rotation axis of the fan impeller. A heating resistance wire 4 with its axis horizontally set is installed on the rotating bracket. The axial length of the heating resistance wire 4 is not shorter than the diagonal length of the fan casing. During the rotation of the rotating bracket with the heating resistance wire, the length of the vertical projection of the heating resistance wire on the cross-section of the inner cavity of the fan casing changes.
[0030] In this embodiment, the rotating bracket includes a first vertical arm 3 and a second vertical arm 10 symmetrically arranged with the rotation axis of the rotating bracket as the center line of symmetry. One end of the heating resistance wire 4 is fixed to the first vertical arm 3, and the other end of the heating resistance wire 4 is fixed to the second vertical arm 10. The rotating bracket also includes a vertically arranged bracket shaft 1, with a horizontal connecting arm 2 at the bottom of the bracket shaft. The horizontal connecting arm 2 has a connecting arm ventilation hole 8 that extends through the horizontal connecting arm in the vertical direction. The first vertical arm 3 and the second vertical arm 10 are fixed to both ends of the horizontal connecting arm 2. The upper end of the bracket shaft extends into the equipment interlayer and is connected to the motor shaft of the first motor for transmission.
[0031] Two guide rods 24, whose guiding direction is aligned with the axis of the heating resistance wire, are fixed between the first vertical arm 3 and the second vertical arm 10. A first sliding head 5 and a second sliding head 25, capable of relative or backward movement, are mounted on the guide rods 24. The upper end of the first sliding head 5 and the upper end of the second sliding head 25 are in contact with the heating resistance wire and are electrically connected. The first and second sliding heads are connected in series in the heating power supply circuit of the heating resistance wire and are driven by a sliding head drive mechanism. In other words, only the heating resistance wire between the first and second sliding heads will be energized and generate heat. When the first and second sliding heads move relative to each other, the length of the heating resistance wire between them becomes shorter, resulting in a shorter length of heating resistance wire capable of generating heat. When the first and second sliding heads move backward, the length of the heating resistance wire between them becomes longer, resulting in a longer length of heating resistance wire capable of generating heat and generating more heat.
[0032] The sliding head drive mechanism includes a fixed shaft 12 fixed to the upper end of the fan casing via a fixed shaft bracket 6. The fixed shaft bracket 6 includes four support rods spaced circumferentially, two of which are fixedly connected to the inner wall of the long side of the fan casing, and two of which are fixedly connected to the inner wall of the short side of the fan casing. A support ventilation channel is formed between adjacent support rods to allow airflow to pass through from top to bottom. The fixed shaft 12 is coaxially arranged with the fan impeller 13. A first steel wire rope 27 connected to the first sliding head 5 and a second steel wire rope 28 connected to the second sliding head 25 are wound around the upper end of the fixed shaft. The first steel wire rope 27 and the second steel wire rope 28 are arranged sequentially along the axial direction of the fixed shaft. A return spring 26 is provided between the first sliding head and the second sliding head. When the first motor rotates in one direction with the rotating bracket, the fixed shaft does not rotate. Therefore, the first and second steel wire ropes will be wound around the fixed shaft. In this way, the first and second sliding heads can move relative to each other under the pulling action of the corresponding steel wire ropes, and the length of the heating resistance wire that can conduct electricity and generate heat becomes shorter. When the first motor rotates in the other direction with the rotating bracket, the first and second steel wire ropes are released from the fixed shaft. Under the action of the return spring, the first and second sliding heads move in opposite directions, and the length of the heating resistance wire that can conduct electricity and generate heat increases, similar to a sliding rheostat.
[0033] During operation, the fan impeller generates a downward airflow. The hot airflow enters the baking chamber through the fan chamber outlet and then flows back into the fan chamber through the fan chamber inlet, forming a cycle. When a change in heat energy is needed, the first motor drives the rotating bracket, which in turn rotates the heating resistance wire. This change in the wire's orientation can be completed within a 90° rotation of the bracket, enabling efficient changes in airflow heat. Figures 4-6 As shown, the projected length of the heating resistance wire on the cross-section of the fan cylinder changes. The heat of the heating resistance wire outside the cross-section of the fan cylinder cannot be effectively carried away by the airflow, thus altering the heat in the airflow. Conversely, when the projected length of the heating resistance wire on the cross-section of the fan cylinder shortens, the length of the heating resistance wire connected in series in the heating power supply circuit also shortens, reducing energy consumption. If the rotating bracket rotates continuously in one direction, for example, by an angle exceeding 360°, the length of the heating resistance wire connected in series in the heating power supply circuit will continuously shorten, becoming shorter than the short side length of the fan cylinder, or even shorter, providing a greater range of airflow heat variation and enabling the oven to have a wider range of applications. Of course, in other embodiments of the invention, the first sliding head and the second sliding head can also be fixed heads with a fixed spacing. In this case, the length of the heating resistance wire connected in series in the heating power supply circuit will not change, and the change in heat in the airflow is achieved solely by the change in the projected length of the heating resistance wire on the cross-section of the fan cylinder.
[0034] In the foregoing description of this specification, unless otherwise expressly specified and limited, the terms "fixed," "installed," "connected," or "linked" should be interpreted broadly. For example, the term "linked" can refer to a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; or it can refer to the internal communication of two components or the interaction between two components. Therefore, unless otherwise expressly limited in this specification, those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0035] Based on the above description in this specification, those skilled in the art will also understand that terms used, such as "upper," "lower," "front," "rear," "left," "right," "length," "width," "thickness," "vertical," "horizontal," "top," "bottom," "inner," "outer," "axial," "radial," "circumferential," "center," "longitudinal," "transverse," "clockwise," or "counterclockwise," are terms indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings of this specification. They are only for the purpose of facilitating the explanation of the present invention and simplifying the description, and do not imply that the devices or elements involved must have the specific orientation, or be constructed and operated in a specific orientation. Therefore, the above-mentioned orientation or positional relationship terms should not be understood or interpreted as limitations on the present invention.
[0036] Furthermore, the terms "first" or "second," etc., used in this specification to refer to numbers or ordinal numbers are for descriptive purposes only and should not be construed as indicating, explicitly or implicitly, relative importance or specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this specification, "a plurality of" means at least two, such as two, three, or more, unless otherwise explicitly specified.
[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A hot air circulating oven, comprising a housing, wherein a circulating fan, a temperature sensor, and an electrically energized heating resistance wire are disposed within the housing, characterized in that: The circulating fan includes a vertically arranged fan casing and a fan impeller disposed inside the fan casing. The rotation axis of the fan impeller extends vertically. The fan casing is a square cylinder. A rotating bracket is rotatably mounted on the upper side of the fan casing. The rotating bracket is driven by a first motor and is coaxial with the fan impeller. A heating resistance wire with its axis horizontally arranged is disposed on the rotating bracket. The axial length of the heating resistance wire is not less than the diagonal length of the fan casing. As the rotating bracket rotates with the heating resistance wire, the length of the vertical projection of the heating resistance wire on the fan casing changes. The rotating support includes a first vertical arm and a second vertical arm symmetrically arranged about the rotation axis of the rotating support as the center line of symmetry. One end of the heating resistance wire is fixed to the first vertical arm, and the other end of the heating resistance wire is fixed to the second vertical arm. A guide rod is fixed between the first and second vertical arms, with its guiding direction aligned with the axis of the heating resistance wire. The guide rod is equipped with a first sliding head and a second sliding head capable of relative or opposite movement. The upper end of the first sliding head and the upper end of the second sliding head are electrically connected to the heating resistance wire. The first and second sliding heads are connected in series in the heating power supply circuit of the heating resistance wire and are driven by a sliding head drive mechanism. The sliding head drive mechanism includes a fixed shaft fixed to the upper end of the fan casing via a fixed shaft bracket. The fixed shaft is coaxial with the fan impeller. The fixed shaft bracket is provided with a bracket ventilation channel extending in the vertical direction. A first steel wire rope connected to the first sliding head and a second steel wire rope connected to the second sliding head are wound around the upper end of the fixed shaft. A sliding head return spring is provided between the first sliding head and the second sliding head.
2. The hot air circulating oven according to claim 1, characterized in that: The rotating bracket also includes a vertically arranged bracket shaft, with a horizontal connecting arm at the bottom of the bracket shaft. The horizontal connecting arm has a connecting arm ventilation hole that runs through the horizontal connecting arm in the vertical direction. The first vertical arm and the second vertical arm are fixed to both ends of the horizontal connecting arm.
3. The hot air circulating oven according to claim 1 or 2, characterized in that: The inner cavity of the box is divided into a fan chamber and a baking chamber arranged on the left and right by a partition. The upper end of the partition is provided with the fan chamber air inlet connecting the fan chamber and the baking chamber, and the lower end of the partition is provided with the fan chamber air outlet connecting the fan chamber and the baking chamber. The circulating fan and the heating resistance wire are located in the fan chamber.
4. The hot air circulating oven according to claim 3, characterized in that: The upper part of the box is provided with an equipment compartment, the first motor is located in the equipment compartment, and the second motor is also located in the equipment compartment. The baking chamber is equipped with a baking rack shaft whose rotation axis extends in the vertical direction. The upper end of the baking rack shaft extends into the equipment compartment and is connected to the second motor for transmission.