Water-free quick-cooling type dough kneading equipment

Abstract

The invention belongs to the field of dough kneading machines, and particularly relates to water-free quick-cooling type dough kneading equipment which comprises a dough cylinder and a dough kneading hook, the dough kneading hook comprises a hook body and a hook shaft, the hook body and the hook shaft are both of a hollow structure, and two fluid outlets are formed in the lower end of the hook body; the hook shaft is externally connected with a dry ice sand blasting machine, the dry ice sand blasting machine sprays out two fluids of dry ice and compressed air, the two fluids of the dry ice and the compressed air are mixtures of dry ice particles and the compressed air, and the air pressure of the two fluids of the dry ice and the compressed air sprayed out of the two-fluid outlet changes in a pulse mode. The dry ice sand blasting machine is used for spraying dry ice particles into the kneaded dough in a compressed air mode, the dough is directly cooled, and compared with an ice particle spraying mode, the mode is water-free quick cooling. The dry ice particles act on the dough in a jet flow manner, so that the inside of the dough becomes fluffy, and the dough kneading time is shortened.

Description

Technical Field

[0001] The present invention belongs to the technical field of dough mixers, and particularly relates to a waterless and quick-cooling dough mixing device. Background Art

[0002] A dough mixer is a mechanical device used to evenly mix flour with water (or other ingredients) to make dough. It is widely used in the fields of catering, food processing, household kitchens, etc., and has the advantages of improving efficiency, saving manpower, and ensuring the quality of dough.

[0003] The main components of a dough mixer include a machine base, a stirrer (such as a dough hook), a dough vat, a transmission device, and a control device, etc. The stirrer is usually made of stainless steel, and some models are equipped with paddle-type or wreath-type stirring blades to meet different stirring requirements. In addition, modern dough mixers may also be equipped with functions such as automatic quantitative water addition, timed shutdown, and automatic discharging, further improving the operation convenience and production efficiency.

[0004] During the use process, the operation steps of a dough mixer generally include: cleaning the material vat, adding flour, adding water in proportion, starting the machine to stir for 4 - 8 minutes, and taking out the dough and cleaning the equipment after the dough is formed.

[0005] For the dough mixing of large doughs, there are the following problems:

[0006] During the stirring process of the stirring hook, heat is generated due to friction, which will cause the temperature of the dough to gradually rise. Once the dough temperature exceeds 30°C, the yeast activity of the dough will gradually decrease until it becomes inactivated.

[0007] Therefore, large dough mixers generally are equipped with a cooling device to cool the dough vat. Usually, the method of directly adding crushed ice into the dough is not adopted mainly because after the crushed ice melts into water, it is easy to cause the water volume in the dough to be difficult to control, thus affecting the quality of the dough gluten formation.

[0008] Currently, for the cooling of the dough vat, most are for the cylinder wall or the cylinder bottom, and cooling water or refrigerant is used for cooling. For example, in the "cooling water diversion tray and dough mixer cooling assembly" with the publication (announcement) number: CN111937925B, cooling water is circulated with the bottom of the dough bucket for stable cooling. These cooling technologies have a problem, that is, the energy-saving effect is poor, especially for dough mixers where the dough vat needs to rotate. The main reason is that the cooling is concentrated on the dough vat, and the dough inside the dough vat has limited contact with the dough vat wall, which is bound to cause more waste of cooling capacity; the larger the volume of the dough vat, the more serious the waste.

[0009] Based on this, the present invention is proposed. Summary of the Invention

[0010] The object of the present invention is to provide a waterless and quick-cooling dough kneading device to solve the above problems.

[0011] A waterless and quick-cooling dough kneading device includes a dough vat, a dough kneading hook, and a driving mechanism for driving the dough kneading hook to rotate and for adjusting the distance between the dough kneading hook and the dough vat. The dough kneading hook includes a hook body and a hook shaft, both of which are hollow structures. A two-fluid outlet is provided at the lower end of the hook body. A dry ice sandblaster is externally connected to the hook shaft. The dry ice sandblaster sprays a two-fluid of dry ice and compressed air, which is a mixture of dry ice particles and compressed air. The air pressure of the two-fluid of dry ice and compressed air ejected from the two-fluid outlet changes in a pulsed manner.

[0012] For further improvement, a pipeline mechanism and a pulsed air pressure driving device for changing the internal air pressure of the pipeline mechanism are installed between the hook shaft and the dry ice sandblaster. The pipeline mechanism includes a connecting pipe coaxially and rotatably connected to the hook shaft and a flexible hose connected to the connecting pipe. The flexible hose is connected to the dry ice sandblaster through the pulsed air pressure driving device.

[0013] For further improvement, the pulsed air pressure driving device includes a first branch pipe, a second branch pipe, a third branch pipe, and an electric cylinder. The tail end of the first branch pipe is communicated with the output end of the dry ice sandblaster. The tail end of the second branch pipe is communicated with the flexible hose. The head ends of the first branch pipe and the second branch pipe are both communicated with the middle part of the third branch pipe. A cover is installed at the tail end of the third branch pipe. The head end of the third branch pipe is connected to the electric cylinder. The telescopic end of the electric cylinder is located inside the third branch pipe, and a push block is fixedly installed at the telescopic end of the electric cylinder.

[0014] For further improvement, both the first branch pipe and the second branch pipe are perpendicular to the third branch pipe, and the included angle ζ between the first branch pipe and the second branch pipe satisfies 72° ≤ ζ ≤ 86°.

[0015] For further improvement, the particle size of the dry ice particles is 6 - 8 mm, and the peak pressure of the compressed air is 3.7 bar.

[0016] For further improvement, the pulsed waveform of the air pressure change of the two-fluid of dry ice and compressed air ejected from the two-fluid outlet is bell-shaped, and the pulse duration is 3 - 6 s.

[0017] For further improvement, the push block is in the shape of an inverted frustum.

[0018] For further improvement, the minimum distance between the push block and the inner wall of the third branch pipe is 1.6 mm.

[0019] For further improvement, the inner diameter of the hook body is gradually decreasing in the downward direction, and the outer diameter of the hook body is also gradually decreasing in the downward direction.

[0020] For further improvement, ζ = 78°.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] 1. The present invention uses a dry ice blasting machine to spray dry ice particles into the dough during dough kneading through compressed air, directly cooling the dough. Compared with the method of spraying ice particles, this method is a waterless rapid cooling method.

[0023] 2. Since the dry ice particles act on the dough in a jet flow manner, it not only makes the inside of the dough fluffy, but also helps to shorten the dough kneading time.

[0024] 3. By directly adding a green and harmless refrigerant (dry ice particles), and using a pulse pneumatic driving device to distribute the dry ice particles more evenly inside the dough, the loss of dry ice particles is reduced, and finally the energy-saving effect of the equipment is good. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic structural diagram of the waterless rapid cooling dough kneading equipment described in the present invention;

[0026] Figure 2 It is a schematic structural diagram of the pulse pneumatic driving device described in the present invention;

[0027] Figure 3 It is a schematic connection diagram of the first branch pipe, the second branch pipe, and the third branch pipe described in the present invention;

[0028] Figure 4 It is a physical photo of the dough cylinder during assembly in the present invention;

[0029] Figure 5 It is a physical photo of the small dough after successful dough kneading in Example 2 being stretched into a dough film;

[0030] Figure 6 It is a physical photo of the small dough after unsuccessful dough kneading when the dry ice particles are 3 - 6 mm being stretched into a dough film;

[0031] Figure 7 It is a curve graph showing the relationship between ζ and power consumption. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] The present invention will be further described in detail below through specific embodiments in conjunction with the drawings.

[0033] In the description of the present invention, it should be noted that unless otherwise specified, the meaning of "a plurality of" is two or more; the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present invention. In addition, the terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0034] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] Embodiment 1

[0036] As Figure 1 、 4 shown, the anhydrous rapid cooling dough mixing device includes a dough vat 10, a dough hook, and a driving mechanism for driving the dough hook to rotate self and the distance between the dough hook and the dough vat 10. The dough hook includes a hook body 20 and a hook shaft, and the driving mechanism is driven by a motor 40.

[0037] If it is a small dough vat 10, the driving mechanism can only drive the dough hook to rotate self; for a large dough vat 10, for example, with a diameter of 1540 mm, it is also necessary to adjust the distance between the dough hook and the dough vat 10. At this time, it can be achieved through a translation mechanism; in addition, it can also be through the rotation of the dough vat 10 to accelerate the dough mixing efficiency. The technology for driving the dough hook to rotate self and the distance between the dough hook and the dough vat 10 is the prior art and will not be elaborated here.

[0038] Both the hook body 20 and the hook shaft are hollow structures. A two-fluid outlet 21 is provided at the lower end of the hook body 20; a dry ice sandblaster is externally connected to the hook shaft. The dry ice sandblaster sprays a two-fluid of dry ice and compressed air. The two-fluid of dry ice and compressed air is a mixture of dry ice particles and compressed air, and the air pressure of the two-fluid of dry ice and compressed air sprayed at the two-fluid outlet 21 changes in a pulsed manner.

[0039] The dry ice blasting machine sprays dry ice particles at a high speed by accelerating them with compressed air. The dry ice particles collide into the interior of the small dough at a high speed in the compressed air flow, mainly achieving the cooling of the small dough. By controlling the particle size of the dry ice particles, after the dry ice particles sublime, the interior of the small dough can become fluffy.

[0040] This direct addition to the interior of the small dough has a higher cooling efficiency, and the dry ice particles are driven into the interior of the small dough at a high speed by compressed air, thus minimizing waste; compared with the cooling methods of the prior art, the cooling method of the present invention is more energy-saving.

[0041] The air pressure of the two-fluid of dry ice and compressed air ejected at the two-fluid outlet 21 changes in a pulsed manner, and its main function is to enable the dry ice particles to penetrate deeper into the interior of the small dough.

[0042] Embodiment 2

[0043] A pipeline mechanism is installed between the hook shaft and the dry ice blasting machine, and a pulsed air pressure driving device for changing the air pressure inside the pipeline mechanism. The pipeline mechanism includes a connecting pipe 30 coaxially and rotatably connected to the hook shaft, and a hose connected to the connecting pipe 30. The hose is connected to the dry ice blasting machine through the pulsed air pressure driving device. The connecting pipe 30 can be kept fixed. Because the distance needs to be adjusted, it must be a hose. Generally, a fiber-reinforced polyurethane hose or a fiber-reinforced nylon hose is used for the hose.

[0044] The pulsed air pressure driving device includes a first branch pipe 51, a second branch pipe 52, a third branch pipe 53 and an electric cylinder 55. The tail end of the first branch pipe 51 is communicated with the output end of the dry ice blasting machine. The tail end of the second branch pipe 52 is communicated with the hose. The head ends of the first branch pipe 51 and the second branch pipe 52 are both communicated with the middle part of the third branch pipe 53. A cover 54 is installed at the tail end of the third branch pipe 53. The head end of the third branch pipe 53 is connected to the electric cylinder 55. The telescopic end of the electric cylinder 55 is located inside the third branch pipe 53, and a push block 56 is fixedly installed at the telescopic end of the electric cylinder 55.

[0045] First, the electric cylinder 55 can be controlled by a PLC. Then, by inputting a controllable waveform, the telescopic frequency of the telescopic end of the electric cylinder 55 can be controlled to reach the preset frequency. Driven by the electric cylinder 55, the push block 56 continuously moves up and down through the connection between the first branch pipe 51 and the third branch pipe 53, so that the air pressure change finally output from the second branch pipe 52 can be changed into a specific waveform. Since the subsequent pulse waveform is bell-shaped, for quick response, the push block 56 is designed as an inverted frustum structure. Because if it is cylindrical, not only is it easy for dry ice particles to get "stuck", but also when quickly switching at the connection, a sufficient continuous reference air pressure can still be maintained; considering the effect of changing the air pressure change comprehensively, the minimum distance between the push block 56 and the inner wall of the third branch pipe 53 is 1.6 mm.

[0046] Both the first branch pipe 51 and the second branch pipe 52 are perpendicular to the third branch pipe 53, and the included angle between the first branch pipe 51 and the second branch pipe 52 is ζ, where 72° ≤ ζ ≤ 86°. Preferably, ζ = 78°.

[0047] The inner diameter of the hook body 20 is gradually decreasing in the direction from top to bottom, and the outer diameter of the hook body 20 is gradually decreasing in the direction from top to bottom.

[0048] During the process of stirring flour and water in the surface cylinder 10 into a large number of small doughs, before it becomes a large dough (all the flour is grouped into a large dough), start the dry ice sandblaster and the pulsed air pressure driving device. The particle size of the dry ice particles is 6 - 8 mm, and the peak pressure of the compressed air is 3.7 bar. The pulsed waveform of the air pressure change of the two-fluid of dry ice and compressed air ejected from the two-fluid outlet 21 is bell-shaped, and the pulse duration is 3 - 6 s.

[0049] The dry ice flow rate is designed according to the weight of the dough. For example, for a dough with a weight of 15 kg, the dry ice flow rate is maintained at about 0.3 ± 0.03 kg / min.

[0050] Since the existing dry ice sandblasters usually output a constant pressure, specific equipment must be used to change the air pressure to make it a pulsed air pressure. And using a conventional air pump, even a variable-frequency air pump, cannot quickly change the air pressure. Because an air pump generally increases the air pressure by compressing air, usually the air pressure can be adjusted to the required level within a few minutes, which makes the pulse duration far from reaching the required level of the present invention. Moreover, with the secondary action of the dry ice particles passing through the air pump, the sublimation will be further accelerated, resulting in a significant increase in the consumption of dry ice and a sharp increase in the adjustment difficulty. However, the pulsed air pressure driving device of the present invention can quickly change the air pressure of the compressed air. For example, the pulse duration can be shortened to within 6 s; moreover, its overall structure is similar to a tee structure, which is more suitable for dry ice particles to pass through, and the loss of dry ice particles is lower.

[0051] After the small dough inside the dough mixing cylinder 10 becomes large dough, at this time, the air pressure of the compressed air and the particle size of the dry ice particles are reduced. The particle size of the dry ice particles is less than 3 mm. The pulse air pressure driving device stops, and the rotation speed of the dough hook is reduced to below 30 r / min. The air pressure of the compressed air is a constant pressure and remains at 1.8 bar. At this time, the ejected dry ice particles mainly play a role in cooling. They will gradually rise from the bottom of the dough mixing cylinder 10 to cool the large dough inside the dough mixing cylinder 10.

[0052] In this embodiment, 10 kg of flour and 5 kg of water are used for dough mixing, and the dough mixing time is controlled within 13 min. During the dough mixing process, it is found that all the flour forms into dough at the 7th min. After the dough mixing is completed, a small piece of dough is taken out and stretched into a dough film until a hole appears. The dough film has good transparency, and the inside of the hole is smooth without serrations, indicating that the dough mixing is successful, as Figure 5 shown.

[0053] If only compressed air below 0 °C is ejected at the two-fluid outlet 21 for cooling, since there is no other freezing medium, cooling the high-speed ejected compressed air has always been a major problem. Even if the gas cylinder is frozen, the flowing compressed air will reheat due to friction.

[0054] If liquid nitrogen particles are used instead of dry ice particles, it is found that there will be a large amount of "underdone" in the dough, that is, there will be a large number of frozen dough lumps. Therefore, in the present invention, dry ice particles are used, and the particle size of the dry ice particles needs to be strictly controlled. The carbon dioxide generated after the dry ice particles volatilize is also non-toxic and harmless.

[0055] It is found in the simulation test that the dry ice particles will seriously affect the dough mixing effect. The main reasons are that the sizes of the dry ice particles are different, the shooting speeds are different, the impact forces are different, the temperatures inside the dough are different, and the degrees of influence on the denaturation of proteins in the dough are also different, etc. The final test results are shown in Table 1:

[0056] Table 1

[0057]

[0058] In Table 1, the dough proofing time is measured in an environment of 25 ± 1 °C until the dough proofs to twice its original size. It can be seen from this that the dry ice particles are preferably 6 - 8 mm.

[0059] Example 3

[0060] The difference between this example and Example 2 is that in this example, the pulse waveform of the air pressure change of the two-fluid of dry ice and compressed air ejected at the two-fluid outlet 21 is rectangular, and the rest are the same.

[0061] Example 4

[0062] The difference between this example and Example 2 is that in this example, the pulse waveform of the air pressure change of the two-fluid of dry ice and compressed air ejected from the two-fluid outlet 21 is a triangular waveform, and the rest are the same.

[0063] Example 5

[0064] The difference between this example and Example 2 is that in this example, the pulse waveform of the air pressure change of the two-fluid of dry ice and compressed air ejected from the two-fluid outlet 21 is a stepped waveform, and the rest are the same.

[0065] In the present invention, although dry ice particles are used, even if the particle size has been controlled, if the impact force of the pulse is not controlled, the impact force is too small, resulting in a large number of dry ice particles concentrating on the surface layer of the large dough, which will cause the surface of the dough to become hard and dead skin to fall off, affecting subsequent proofing; if the impact force is too large, the dry ice particles will penetrate too deep into the large dough, and the dry ice particles cannot melt or sublimate in time, easily freezing the dough around it, thus generating a large number of uneven hard flour particles mixed in. By randomly sampling the large dough after kneading, stretching it into a mask, and then touching and observing whether there are hard flour particles, the appearance rate of hard flour particles is calculated. The test results are shown in Table 2:

[0066] Table 2

[0067] Dry ice particle size Dough kneading effect Example 2 No dead skin shedding during dough kneading, appearance rate of hard dough particles = 0 Example 3 No dead skin shedding during dough kneading, appearance rate of hard dough particles = 23% Example 4 No dead skin shedding during dough kneading, appearance rate of hard dough particles = 17% Example 5 There is a phenomenon of dead skin shedding during dough kneading

[0068] Example 6

[0069] In this experiment, it was found that if the ζ value affects the loss of dry ice particles inside the tee-like structure, in order to ensure the freezing efficiency of the dry ice particles on the dough, an experiment was carried out with the power consumption of a certain simulation test (accumulative operation for 4 hours), and the results are shown in Figure 7 , from which it can be seen that preferably, ζ = 78°.

[0070] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. An anhydrous and quick-cooling dough kneading device, comprising a dough vat, a dough kneading hook, and a driving mechanism for driving the dough kneading hook to rotate and the distance between the dough kneading hook and the dough vat. The dough kneading hook comprises a hook body and a hook shaft, and is characterized in that: Both the hook body and the hook shaft are hollow structures. A two-fluid outlet is provided at the lower end of the hook body. A dry ice sandblaster is externally connected to the hook shaft. The dry ice sandblaster sprays a two-fluid of dry ice and compressed air. The two-fluid of dry ice and compressed air is a mixture of dry ice particles and compressed air. The air pressure of the two-fluid of dry ice and compressed air ejected from the two-fluid outlet changes in a pulsed manner.

2. The anhydrous quick-cooling dough kneading device according to claim 1, characterized in that: A pipeline mechanism and a pulsed air pressure driving device for changing the internal air pressure of the pipeline mechanism are installed between the hook shaft and the dry ice sandblaster. The pipeline mechanism includes a connecting pipe coaxially and rotatably connected to the hook shaft and a hose connected to the connecting pipe. The hose is connected to the dry ice sandblaster through the pulsed air pressure driving device.

3. The anhydrous quick-cooling dough mixing device according to claim 2, characterized in that: The pulsed air pressure driving device includes a first branch pipe, a second branch pipe, a third branch pipe and an electric cylinder. The tail end of the first branch pipe is communicated with the output end of the dry ice sandblaster. The tail end of the second branch pipe is communicated with the hose. The head ends of both the first branch pipe and the second branch pipe are communicated with the middle part of the third branch pipe. A cover is installed at the tail end of the third branch pipe. The head end of the third branch pipe is connected to the electric cylinder. The telescopic end of the electric cylinder is located inside the third branch pipe. A push block is fixedly installed at the telescopic end of the electric cylinder.

4. The anhydrous quick-cooling dough kneading device according to claim 3, characterized in that: Both the first branch pipe and the second branch pipe are perpendicular to the third branch pipe. The included angle between the first branch pipe and the second branch pipe is ζ, and 72° ≤ ζ ≤ 86°.

5. The anhydrous quick-cooling dough mixing device according to claim 1, characterized in that: The particle size of the dry ice particles is 6 - 8 mm, and the peak pressure of the compressed air is 3.7 bar.

6. The anhydrous quick-cooling dough kneading device according to claim 1, wherein: The air pressure change pulse waveform of the two-fluid of dry ice and compressed air ejected from the two-fluid outlet is bell-shaped, and the duration of the pulse is 3 - 6 s.

7. The anhydrous quick-cooling dough kneading device according to claim 3, wherein: The push block is in the shape of an inverted frustum.

8. The anhydrous quick-cooling dough kneading device according to claim 7, characterized in that: The minimum distance between the push block and the inner wall of the third branch pipe is 1.6 mm.

9. The anhydrous quick-cooling dough kneading device according to claim 1, characterized in that: The inner diameter of the hook body is gradually decreasing in the direction from top to bottom, and the outer diameter of the hook body is gradually decreasing in the direction from top to bottom.

10. A kind of waterless quick-cooling dough mixing equipment according to claim 4, characterized in that: ζ = 78°.

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