Negative pressure sealing structure and negative pressure sealing method and application

Abstract

In a negative pressure sealing structure and a negative pressure sealing method, the cavity is at vacuum negative pressure during use and at ambient air pressure during non-use. The sealing body that cooperates with the cavity also changes with the pressure state in the cavity and undergoes corresponding deformation, thereby changing the tightness of the fit between the sealing body and the cavity. When the cavity is in a negative pressure state, the sealing body deforms so that the sealing pressure between the sealing body and the cavity sealing surface increases, and the airtightness is improved; when the cavity is in an ambient air pressure state, the sealing body returns to its initial state, and the sealing pressure between the sealing body and the cavity sealing surface decreases, making it easier for the user to separate the sealing body from the cavity. The vacuum food processor, vacuum fresh-keeping jar, and vacuum press that adopt the negative pressure sealing structure of the present invention improve the user's convenience in putting in and taking out food while ensuring the airtightness in the working state, thereby improving the user experience.

Description

Technical Field

[0001] The invention relates to the technical field of food processing machinery, in particular to a negative pressure sealing structure and a negative pressure sealing method and application. Background Art

[0002] In the existing food processing process, oxidation caused by food contact with air has become an important factor in nutrient loss. When using a food processor or juicer, the degree of contact between food and air is more significant, resulting in greater nutrient oxidation loss.

[0003] In order to reduce the oxidation of nutrients in food, the prior art ZL201210139784.7 "Food processor with electric vacuum pump and method for preparing food liquid by vacuuming" discloses a vacuum food processor, in which a space for accommodating and processing food is formed inside the barrel of the vacuum food processor. During use, the barrel is vacuumed by an electric vacuum pump to discharge the air inside the barrel, so as to reduce oxidation during food processing and reduce nutrient loss. Such vacuum food processors must ensure the sealing degree of the barrel itself during vacuuming. Usually, the barrel of the vacuum food processor is sealed with a movable sealing cover, and the sealing cover and the barrel are generally improved by interference fit to improve air tightness. For example, a single or multiple sealing rings are set between the sealing cover and the barrel to achieve a sealing effect, or the sealing cover and the barrel are directly interference fit. The sealing cover can be made of rigid material or elastic material.

[0004] In other containers such as vacuum fresh-keeping jars, it is also necessary to use a sealing cover to seal the fresh-keeping jar, and the sealing cover and the fresh-keeping jar are generally improved by interference fit to ensure airtightness and sealing.

[0005] The greater the interference fit, the tighter and more reliable the seal, and the less likely it is to leak (on the contrary, it is easy to leak due to loose seal). However, the greater the interference fit, the tighter the seal cover is to the mouth of the container (the barrel of the food processor or the fresh-keeping jar), and the more difficult it is to put on / take off the seal cover. This brings inconvenience to the user and a poor user experience.

[0006] The vacuum seal is achieved by interference fit, which also appears in vacuum presses, such as ZL201610224635.9. A sliding sealing piston is set in the pressing cylinder. The press needs to evacuate the internal space such as the pressing chamber of the pressing cylinder during operation. The side wall of the sealing piston and the inner wall of the pressing cylinder are used to achieve sliding sealing through interference fit. Generally, a rigid or elastic sealing ring is provided on the sealing piston, or (without a sealing ring on the sealing piston) the interference fit is achieved between the sealing piston itself and the inner wall of the pressing cylinder. When the tightness of the fit between the sealing piston and the pressing cylinder is improved, the resistance when the piston and the pressing cylinder slide will be increased. Since the actions of inserting the sealing piston into the pressing cylinder before the juice extraction begins and removing the sealing piston from the pressing cylinder after the juice extraction is completed are all done manually by the user, the user needs to apply a large force to the sealing piston, which brings inconvenience to the user and the user experience is poor.

[0007] In short, in vacuum mechanical devices that use interference fit to achieve sealing, there is a contradiction between sealing reliability and operational convenience (that is, the convenience of putting on / off the sealing cover or sealing piston, etc.). However, sealing must be guaranteed in vacuum mechanical devices, so putting on / off the sealing cover or inserting / removing the sealing piston is inevitably more laborious. Summary of the invention

[0008] The technical problem to be solved by the present invention is to provide a negative pressure sealing structure and a negative pressure sealing method and application.

[0009] The technical solution adopted by the present invention to solve the technical problems existing in the known technology is:

[0010] The negative pressure sealing structure of the present invention comprises a sealing body and a cavity. The sealing body is used to seal the cavity. The sealing body is a passive negative pressure deformation sealing structure. When the sealing body seals the cavity under ambient air pressure, the sealing pressure between the sealing body and the sealing surface of the cavity is an initial pressure, and the initial pressure is greater than or equal to zero. When a vacuum negative pressure state is formed inside the cavity, the sealing body is deformed under the vacuum negative pressure, so that the sealing pressure between the sealing body and the sealing surface of the cavity is greater than the initial pressure, thereby improving the sealing degree between the sealing body and the cavity.

[0011] The present invention can also adopt the following technical measures:

[0012] The sealing body is a sealing cover, the sealing surface of the cavity is a contact surface between the sealing cover and the side wall of the cavity, and the sealing cover is one of the following structures:

[0013] ①The sealing cover is made of elastic or flexible porous material;

[0014] ② A sealing ring is provided between the sealing cover and the side wall of the cavity, and the sealing ring is made of an elastic or flexible porous material;

[0015] ③ A sealing ring is provided between the sealing cover and the side wall of the cavity, wherein the sealing ring is a hollow sealing ring having at least one air chamber therein, and the air chamber is closed or connected to the external environment;

[0016] ④ The sealing cover includes a top and a side wall. The side wall of the sealing cover is inserted into the cavity or covered outside the cavity. An annular sealing belt is provided between the side wall of the sealing cover and the side wall of the cavity. An air guide hole is provided through the side wall of the sealing cover. When the sealing cover seals the cavity, one end of the air guide hole is connected to the external environment, and the other end of the air guide hole is covered by the annular sealing belt;

[0017] ⑤ The sealing cover includes a top and a side wall. The side wall of the sealing cover is inserted into the cavity or covered outside the cavity. A hollow sealing ring is provided between the side wall of the sealing cover and the side wall of the cavity. At least one air chamber is provided in the hollow sealing ring. There is an air guide hole penetrating the side wall of the sealing cover. When the sealing cover seals the cavity, one end of the air guide hole is connected to the external environment, and the other end of the air guide hole is covered by the hollow sealing ring. The air chamber in the hollow sealing ring is closed or the air chamber is connected to the external environment through the air guide hole.

[0018] ⑥ The sealing cover includes a top and a side wall. The side wall of the sealing cover is inserted into the cavity or covered outside the cavity. A porous material sealing ring is provided between the side wall of the sealing cover and the side wall of the cavity. There is an air guide hole penetrating the side wall of the sealing cover. When the sealing cover seals the cavity, one end of the air guide hole is connected to the external environment, and the other end of the air guide hole is covered by the porous material sealing ring.

[0019] In structures ①, ② or ⑥, a plurality of closed independent air chambers are formed in the porous material, and a wear-resistant layer is coated outside the porous material.

[0020] An annular deformation belt is arranged in the middle of the belt wall of the annular sealing belt in structure ④; an annular groove is arranged on the side wall of the sealing cover and / or the belt wall of the annular sealing belt, the position of the annular groove corresponds to the position of the deformation belt on the belt wall of the annular sealing belt, and the deformation groove is connected with the air guide hole.

[0021] The sealing body is a sealing piston disposed in the cavity, the sealing surface of the cavity is the contact surface between the sealing piston and the inner wall of the cavity, and the sealing piston is one of the following structures:

[0022] ⑴The sealing piston is made of elastic or flexible porous material;

[0023] (2) A sealing ring is provided between the sealing piston and the inner wall of the cavity, and the sealing ring is made of an elastic or flexible porous material;

[0024] (3) A sealing ring is provided between the sealing piston and the inner wall of the cavity, wherein the sealing ring is a hollow sealing ring having at least one air chamber therein, and the air chamber is closed or communicated with the external environment;

[0025] (4) An annular sealing belt is provided between the side wall of the sealing piston and the inner wall of the cavity, and an air guide hole is provided on the side wall of the sealing piston. When the sealing piston slides and seals the cavity, one end of the air guide hole is connected to the external environment outside the cavity, and the other end of the air guide hole is covered by the annular sealing belt;

[0026] (5) A hollow sealing ring with a hollow air chamber is provided between the side wall of the sealing piston and the inner wall of the cavity, at least one air chamber is provided in the hollow sealing ring, and an air guide hole is provided on the side wall of the sealing piston. When the sealing piston slides and seals the cavity, one end of the air guide hole is connected to the external environment of the cavity, and the other end of the air guide hole is covered by the hollow sealing ring. The air chamber in the hollow sealing ring is closed or the air chamber is connected to the external environment through the air guide hole;

[0027] (6) A porous material sealing ring is provided between the side wall of the sealing piston and the inner wall of the cavity, and an air guide hole is provided on the side wall of the sealing piston. When the sealing piston slides and seals the cavity, one end of the air guide hole is connected to the external environment, and the other end of the air guide hole is covered by the porous material sealing ring.

[0028] In the structures ⑴, ⑵ or ⑹, a plurality of closed independent air chambers are formed in the porous material, and a wear-resistant layer is coated outside the porous material; or in the structure ⑷, an annular deformation band is arranged in the middle of the band wall of the annular sealing band; an annular groove is arranged on the side wall of the sealing piston and / or the band wall of the annular sealing band, the position of the annular groove corresponds to the position of the deformation band on the band wall of the annular sealing band, and the deformation groove is connected with the air guide hole.

[0029] The negative pressure sealing method of the present invention comprises the following steps:

[0030] A. The sealing body seals the cavity under ambient pressure, and the sealing pressure between the sealing body and the sealing surface of the cavity is the initial pressure, which is greater than or equal to zero;

[0031] B. Evacuate the cavity to generate a vacuum negative pressure inside the cavity, the sealing body deforms under the vacuum negative pressure, and the sealing pressure between the sealing body and the sealing surface of the cavity is greater than the initial pressure;

[0032] C. The vacuum negative pressure in the cavity reaches a set value, the sealing pressure between the sealing body and the sealing surface of the cavity reaches a maximum value, and the sealing degree between the sealing body and the cavity is improved;

[0033] D. When the sealing body needs to be opened or removed, the vacuum state in the cavity is released, the deformation of the sealing body is restored to the initial state, and the sealing pressure between the sealing body and the sealing surface of the cavity is restored to the initial pressure;

[0034] E. Separate the sealing body from the cavity.

[0035] The vacuum food processor of the present invention comprises a barrel body and a cutter disc body, the barrel body and the cutter disc body are connected, a sealing ring is arranged between the barrel body and the cutter disc body, the sealing ring is a porous material sealing ring or a hollow sealing ring, when the barrel body and the cutter disc body are connected under ambient air pressure, the sealing pressure of the barrel body and the cutter disc body on the sealing ring is an initial pressure, and the initial pressure is greater than zero; when a vacuum negative pressure state is formed inside the barrel body, the sealing ring is deformed under the vacuum negative pressure, and the sealing pressure of the barrel body and the cutter disc body on the sealing ring is greater than the initial pressure.

[0036] The negative pressure sealing structure of the present invention is applied to a vacuum food processor. The vacuum food processor comprises a sealing cover and a barrel body, and the cavity is the barrel body.

[0037] The negative pressure sealing structure of the present invention is used in a vacuum press. The vacuum press comprises a pressing cylinder and a sealing piston, and the cavity is the pressing cylinder.

[0038] The advantages and positive effects of the present invention are:

[0039] In the negative pressure sealing structure and the negative pressure sealing method and application of the present invention, the sealing body is used to seal the cavity. The cavity is vacuum negative pressure during use and ambient pressure during non-use. The sealing body that cooperates with the cavity also undergoes corresponding deformation as the pressure state in the cavity changes (negative pressure state / ambient pressure), thereby changing the tightness of the fit between the sealing body and the cavity. When the cavity is in a negative pressure state, the sealing body deforms so that the sealing pressure between the sealing surface of the cavity is increased, and the airtightness is improved; when the cavity is in an ambient pressure state, the sealing body returns to the initial state, and the sealing pressure between the sealing body and the sealing surface of the cavity is reduced, which facilitates the user to separate the sealing body from the cavity. The vacuum food processor, vacuum fresh-keeping jar and vacuum press that adopt the negative pressure sealing structure of the present invention improve the user's convenience in putting in and taking out food while ensuring the airtightness in the working state, and improve the user experience. It solves the long-standing contradiction between "the airtightness of the sealing body and the cavity in the working state and the convenience of operation in the non-working state". BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic diagram of Example 1 of the negative pressure sealing structure of the present invention;

[0041] Figure 2 is a schematic diagram of Example 2 of the negative pressure sealing structure of the present invention;

[0042] Figure 3 is a schematic diagram of Example 3 of the negative pressure sealing structure of the present invention;

[0043] Figure 4 is a schematic diagram of Example 4 of the negative pressure sealing structure of the present invention;

[0044] Figure 5 is a schematic diagram of Example 5 of the negative pressure sealing structure of the present invention;

[0045] Figure 6 is a schematic diagram of Example 6 of the negative pressure sealing structure of the present invention;

[0046] Figure 7 is a schematic diagram of the cavity air pressure in the initial state of the embodiment 7 of the negative pressure sealing structure of the present invention;

[0047] Figure 8 is a schematic diagram of the cavity air pressure of Example 7 of the negative pressure sealing structure of the present invention when it is in a vacuum negative pressure state;

[0048] Fig. 9 is a schematic diagram of Example 8 of the negative pressure sealing structure of the present invention;

[0049] Fig.10 is a schematic diagram of Example 9 of the negative pressure sealing structure of the present invention;

[0050] Fig.11 is a schematic diagram of embodiment 10 of the negative pressure sealing structure of the present invention;

[0051] Fig.12 is a schematic diagram of Example 11 of the negative pressure sealing structure of the present invention;

[0052] Fig.13 is a schematic diagram of Example 12 of the negative pressure sealing structure of the present invention;

[0053] Fig.14 is a schematic diagram of the cavity air pressure in the initial state of the embodiment 13 of the negative pressure sealing structure of the present invention;

[0054] Fig.15 is a schematic diagram of the cavity air pressure of Example 13 of the negative pressure sealing structure of the present invention when it is in a vacuum negative pressure state;

[0055] Fig.16 is a schematic diagram of Example 14 of the negative pressure sealing structure of the present invention;

[0056] Fig.17 is a schematic diagram of Example 15 of the negative pressure sealing structure of the present invention;

[0057] Fig.18 is a schematic diagram of the cavity air pressure in the initial state of the embodiment 16 of the negative pressure sealing structure of the present invention;

[0058] Fig.19is a schematic diagram of the cavity air pressure of Example 16 of the negative pressure sealing structure of the present invention when it is in a vacuum negative pressure state;

[0059] Fig. 20 is a schematic diagram of Example 17 of the negative pressure sealing structure of the present invention;

[0060] Fig.21 It is a schematic diagram of Example 18 of the negative pressure sealing structure of the present invention. DETAILED DESCRIPTION

[0061] The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments.

[0062] The negative pressure sealing structure of the present invention comprises a sealing body and a cavity, wherein the sealing body is used to seal the cavity, and the sealing body is a passive negative pressure deformation sealing structure. When the sealing body seals the cavity under ambient pressure, the sealing pressure between the sealing body and the sealing surface of the cavity is the initial pressure, and the initial pressure is greater than or equal to zero; when a vacuum negative pressure state is formed inside the cavity, the sealing body is deformed under the vacuum negative pressure, so that the sealing pressure between the sealing body and the sealing surface of the cavity is greater than the initial pressure, and the sealing degree between the sealing body and the cavity is improved. The sealing body can seal the cavity under ambient pressure (the state in which the initial pressure is greater than zero), or there is a gap between the sealing body and the cavity under ambient pressure (the state in which the initial pressure is zero), but when the cavity is evacuated, the total air flow rate of the gap per unit time is less than the unit flow rate of air discharged from the cavity, so that the space between the sealing body and the cavity forms a negative pressure when evacuating. After negative pressure is formed in the cavity, due to the pressure difference between the inside and outside of the cavity, the sealing body undergoes volume expansion and deformation to seal the cavity, and increases the sealing pressure, i.e., the bonding force, between the sealing body and the cavity. In the working state, i.e., when the cavity is evacuated, the sealing pressure between the sealing body and the cavity is greater than the sealing pressure in the non-working state, i.e., when the ambient air pressure in the cavity is restored. The two are easy to separate in the non-working state, while they tend to be airtightly combined in the working state. The sealing pressure between the sealing body and the cavity changes in association with the air pressure conditions in the cavity without the need for additional external pressure, thereby ensuring the ease of use and reliability of the sealing structure. Compared with the sealing structure of constant sealing pressure with interference fit in the prior art, the sealing body of the present invention can change between different sealing pressure states between the working state and the non-working state, which not only ensures the sealing degree when the cavity is vacuumed, but also ensures the convenience of separation of the two when not working.

[0063] In a specific application, the cavity can be a vacuum stirring barrel or other vacuum sealed container, and the sealing body is a sealing cover. Corresponding to the sealing method between the sealing body and the cavity, the sealing surface of the cavity is located at the side wall of the cavity or the mouth or bottom of the cavity.

[0064] like Figure 1As shown, the sealing cover 1 in Example 1 is arranged above the cavity and inserted into the cavity to close the cavity 2, the sealing surface of the cavity is located at the cavity mouth and the inner wall of the cavity, and is mainly located between the sealing cover and the inner wall of the cavity, the sealing cover is made of elastic or flexible porous material, the porous material can be any one of polymer sponge, foam plastic, rubber sponge, preferably a closed-cell material, that is, a plurality of closed air chambers 3 are formed in the porous material; the sealing cover can seal the cavity under ambient air pressure, but the sealing pressure between the two is small, which is convenient for inserting the sealing cover into the cavity and taking it out of the cavity, and when the cavity is evacuated to form a negative pressure state, the part of the sealing cover made of porous material adjacent to the cavity expands and deforms, thereby making the sealing cover and the cavity fit more closely, and the sealing pressure between the sealing cover and the cavity is increased, thereby improving the airtightness between the joint surfaces of the two.

[0065] like Figure 2 As shown, the sealing cover 1 in Example 2 is arranged above the cavity and surrounds and covers the outside of the cavity 2 to close the cavity. The sealing surface of the cavity is the upper end opening of the cavity and the outer wall of the cavity. The sealing cover is made of an elastic or flexible porous material. The porous material can be any one of a polymer sponge, a foam plastic, and a rubber sponge, preferably a closed-cell material, that is, a plurality of closed air chambers 3 are formed in the porous material; the sealing cover can seal the cavity under ambient air pressure, but the sealing pressure between the two is small, which is convenient for inserting the sealing cover into the cavity and taking the cavity out of the sealing cover. When the cavity is evacuated to form a negative pressure state, the part of the sealing cover made of porous material adjacent to the cavity expands and deforms, thereby making the sealing cover and the cavity fit more closely, and the sealing pressure between the sealing cover and the cavity is increased, thereby improving the airtightness between the joint surfaces of the two.

[0066] like Figure 3 As shown, the sealing cover 1 in Example 3 is inserted into the cavity 2, and a sealing ring 4 is provided between the sealing cover and the side wall of the cavity. The sealing surface of the cavity is the position where the sealing ring contacts the side wall of the cavity. The sealing ring is made of an elastic or flexible porous material. The porous material can be any one of a polymer sponge, a foam plastic, and a rubber sponge, preferably a closed-cell material, that is, a plurality of closed air chambers 3 are formed in the porous material; the gap between the sealing cover and the cavity is filled with the sealing ring, and the sealing cover can seal the cavity through the sealing ring under ambient air pressure, but the sealing pressure of the sealing ring relative to the sealing cover and the cavity is relatively small, which facilitates the sealing cover to close the cavity and separate from the cavity, and when the cavity is evacuated to form a negative pressure state, the sealing ring made of the porous material expands and deforms under the pressure difference between the negative pressure in the cavity and the ambient air pressure, thereby making the sealing cover and the cavity fit more closely, and the sealing pressure between the sealing cover and the cavity is increased, thereby improving the airtightness between the joint surfaces of the two.

[0067] like Figure 4As shown, the sealing cover 1 in Example 4 is arranged at the opening above the cavity 2, the sealing cover is made of rigid or elastic material, and surrounds and covers the outside of the cavity, a sealing ring 4 is arranged between the sealing cover and the side wall of the cavity, and the sealing ring is made of elastic or flexible porous material, and the porous material can be any one of polymer sponge, foam plastic, and rubber sponge, preferably a closed-cell material, that is, a plurality of closed air chambers 3 are formed in the porous material; the gap between the sealing cover and the cavity is filled with the sealing ring, and the sealing cover can seal the cavity through the sealing ring under ambient pressure, but the sealing pressure of the sealing ring relative to the sealing cover and the cavity is smaller, which is convenient for the sealing cover to close the cavity and separate from the cavity, and when the cavity is evacuated to form a negative pressure state, the sealing ring made of porous material expands and deforms under the pressure difference between the negative pressure in the cavity and the ambient pressure, thereby making the sealing cover and the cavity fit more closely, and the sealing pressure between the sealing cover and the cavity is increased, thereby improving the airtightness between the joint surfaces of the two.

[0068] like Figure 5 As shown, in Example 5, the sealing cover is made of a rigid or elastic material, and the sealing cover 1 is inserted into the cavity 2, and a sealing ring is provided between the sealing cover and the inner wall of the cavity. The sealing ring is an annular hollow sealing ring 10, in which there is at least one air chamber 3. In the case of a single air chamber, the air chamber can be arranged to match the shape of the sealing ring. In the case of multiple air chambers, each air chamber is independent and evenly distributed in the sealing ring to improve the uniformity of expansion and deformation of the sealing ring when the cavity is evacuated. The air chamber is closed (or connected to the external environment). When the cavity is evacuated, the cavity generates a vacuum negative pressure relative to each air chamber. The air chamber expands and deforms, causing the sealing ring to deform as a whole, thereby improving the airtightness between the sealing cover and the cavity. When the ambient pressure in the cavity is restored, the pressure condition between the air chamber and the cavity is restored to the initial state, the volume of the hollow sealing ring is reduced, and the bonding force between the sealing cover and the cavity is reduced.

[0069] like Figure 6 As shown, in Example 6, the sealing cover 1 covers the opening at the top of the cavity 2 and covers the outside of the cavity. A sealing ring is provided between the sealing cover and the outer wall of the cavity. The sealing ring is a hollow sealing ring 10, which contains at least one air chamber 3. The air chamber is separated from the internal space of the cavity and is closed. When the cavity is evacuated to generate negative pressure, a pressure difference is generated between the air pressure in the air chamber in the hollow sealing ring and the air pressure in the cavity. The air pressure in the air chamber is greater than the air pressure in the cavity. The air chamber expands under the action of the pressure difference, thereby driving the entire sealing ring to expand during use, so that the sealing cover and the cavity are more tightly combined. The hollow sealing ring can also be connected to the external environment. In the conductive state, the air pressure in the air chamber is always the ambient air pressure. When the cavity is evacuated, there is also a pressure difference between the air chamber and the cavity, so that the hollow sealing ring expands and deforms.

[0070] like Figure 7As shown, in Example 7, the sealing cover 1 includes a top and a side wall. The sealing cover is inserted into the cavity 2. An annular sealing band 5 is provided between the side wall of the sealing cover and the inner wall of the cavity. An air guide hole 6 is provided through the side wall of the sealing cover. When the sealing cover cooperates with the cavity, one end of the air guide hole is connected to the external environment, and the other end of the air guide hole is covered by the annular sealing band. An annular deformation band 7 is provided in the middle of the band wall of the annular sealing band. Preferably, the upper and lower ends of the band wall are respectively fixed to the side wall of the sealing cover. An annular groove 8 is provided on the side wall of the sealing cover and / or the band wall of the annular sealing band. The position of the annular groove corresponds to the position of the deformation band on the band wall of the annular sealing band. The deformation groove is connected to the air guide hole. The air pressure in the deformation groove is the ambient air pressure. In order to intuitively illustrate the deformation of the annular sealing band, the sealing pressure between the annular sealing band and the inner wall of the cavity in the initial state is selected to be zero, that is, the annular sealing band is separated from the inner wall of the cavity. At this time, it is convenient for the sealing cover to be inserted into the cavity or separated from the cavity. Figure 8 As shown, when the cavity is evacuated, a pressure difference is formed between the air pressure in the cavity and the ambient air pressure, and the deformation band 7 expands toward the side wall of the cavity 2, forming a sealing surface between the deformation band and the inner wall of the cavity, thereby increasing the sealing pressure between the annular sealing band and the side wall of the cavity, thereby improving the sealing degree of the sealing cover 1 to the cavity 2.

[0071] like Fig. 9 As shown, in Example 8, the sealing cover 1 includes a top and a side wall, the side wall of the sealing cover is covered on the outside of the cavity 2, an annular sealing band 5 is provided between the inner wall of the sealing cover and the outer wall of the cavity, and an air guide hole 6 is penetrated on the side wall of the sealing cover. When the sealing cover is matched with the cavity, one end of the air guide hole is connected with the external environment, and the other end of the air guide hole is covered by the annular sealing band; the upper and lower ends of the band wall of the annular sealing band are respectively fixed to the inner wall of the sealing cover, and an annular deformation band 7 is provided in the middle of the band wall; an annular groove 8 is provided on the inner wall of the sealing cover and / or the band wall of the annular sealing band, the position of the annular groove corresponds to the position of the deformation band on the band wall of the annular sealing band, the deformation groove is connected with the air guide hole, and the air pressure in the deformation groove is the ambient air pressure. When the cavity is evacuated, a pressure difference is formed between the air pressure in the cavity and the ambient air pressure, and the deformation belt expands toward the outer wall of the cavity, forming a sealing surface between the deformation belt and the outer wall of the cavity, thereby increasing the sealing pressure between the annular sealing belt and the side wall of the cavity, thereby improving the sealing degree of the sealing cover to the cavity.

[0072] like Fig.10 , Fig.11As shown, in Example 9 and Example 10, the sealing cover 1 includes a top and a side wall, the side wall of the sealing cover is inserted into the cavity 2 or covered outside the cavity, a hollow sealing ring 10 is provided between the side wall of the sealing cover and the side wall of the cavity, at least one air chamber 3 is provided in the hollow sealing ring, and an air guide hole 6 is penetrated on the side wall of the sealing cover. When the sealing cover seals the cavity, one end of the air guide hole is connected to the external environment, and the other end of the air guide hole is covered by the hollow sealing ring. The air chamber in the hollow sealing ring is airtight. When the cavity is evacuated to generate negative pressure, a pressure difference is generated between the air pressure in the air chamber in the hollow sealing ring and the ambient air pressure connected through the air guide hole and the air pressure in the cavity. The air pressure in the air chamber is greater than the air pressure in the cavity. The air chamber expands under the action of the pressure difference, thereby driving the sealing ring as a whole to expand during use, so that the sealing cover and the cavity are more closely combined. The hollow sealing ring can be connected to the external environment through the air guide hole 6. In the conductive state, the air pressure in the air chamber is always the ambient air pressure. When the cavity is evacuated, there is also a pressure difference between the air chamber and the cavity, which causes the hollow sealing ring to expand and deform.

[0073] like Fig.12 As shown, in Example 11, the side wall of the sealing cover 1 is inserted into the cavity 2, and a sealing ring 4 of a porous material is provided between the side wall of the sealing cover and the inner wall of the cavity. The porous material can be any one of polymer sponge, foam plastic, and rubber sponge, preferably a closed-cell material, that is, a plurality of closed air chambers 3 are formed in the porous material, and there are air guide holes 6 penetrating the side wall of the sealing cover. When the sealing cover seals the cavity, one end of the air guide hole is connected to the external environment, and the other end of the air guide hole is covered by the sealing ring of the porous material. When the cavity is evacuated to form a negative pressure state, the sealing ring made of the porous material expands and deforms under the pressure difference between the negative pressure in the cavity and the ambient air pressure, and at the same time, each closed air chamber in the porous material is deformed, so that the sealing cover and the cavity are more closely matched, the sealing pressure between the sealing cover and the cavity is increased, and the air tightness between the joint surfaces of the two is improved.

[0074] like Fig.13 As shown, the sealing cover 1 in Example 12 covers the upper part of the cavity 2, and a sealing ring 4 of a porous material is provided between the inner wall of the sealing cover and the outer wall of the upper opening of the cavity. The porous material can be any one of polymer sponge, foam plastic, and rubber sponge, preferably a closed-cell material, that is, a plurality of closed air chambers 3 are formed in the porous material, and there are penetrating air holes 6 on the side wall of the sealing cover. When the sealing cover seals the cavity, one end of the air hole is connected to the external environment, and the other end of the air hole is covered by the sealing ring of the porous material.

[0075] In the sealing cover and sealing ring structure made of the above-mentioned porous material, a wear-resistant layer is preferably coated outside the porous material. The cover wear-resistant layer is made of elastic material such as silicone material. While ensuring that the sealing cover and the sealing ring are in close contact with the sealing surface, the wear resistance of the corresponding components is improved, thereby extending the overall service life of the sealing structure.

[0076] During use, the above-mentioned negative pressure sealing structure can be applied to vacuum food processors, such as vacuum juicers, vacuum presses and vacuum food preservation containers, which require the food storage space to be vacuumed, so as to reduce the contact between food and air during processing or preservation and reduce the oxidation of nutrients.

[0077] The sealing body is a sealing piston arranged in the cavity, the sealing surface of the cavity is the contact surface between the sealing piston and the inner wall of the cavity, and the sealing piston is one of the following structures:

[0078] The sealing piston 9 in Example 13 is arranged inside the cavity and slides along the inner wall of the cavity 2, and the sealing pressure between the side wall of the sealing piston and the sealing surface of the inner wall of the cavity is greater than or equal to zero. When the sealing pressure is equal to zero, it indicates that the outer diameter of the sealing piston is smaller than the inner diameter of the cavity or is in a critical state of contact and non-contact. The state where the sealing pressure is greater than zero, that is, the outer diameter of the piston is larger than the inner diameter of the cavity and forms a sliding seal with the cavity, and the sealing surface of the cavity is located at the contact surface between the inner wall of the cavity and the piston. The sealing piston is made of an elastic or flexible porous material. The porous material can be any one of polymer sponge, foam plastic, and rubber sponge, preferably a closed-cell material, that is, a plurality of closed air chambers 3 are formed in the porous material; in order to more intuitively illustrate the difference before and after vacuuming the cavity, the case where the outer diameter of the sealing piston in the initial state under ambient pressure is smaller than the inner diameter of the cavity is selected for explanation. The structure between the sealing piston 9 and the cavity 2 in the initial state is as follows: Fig.14 As shown, there is a gap between the sealing piston and the cavity, which facilitates the sealing piston to be inserted into the cavity and removed from the cavity. Fig.15 As shown, when the cavity is evacuated to form a negative pressure state, the portion of the sealing piston made of porous material adjacent to the cavity expands and deforms, so that the sealing piston and the cavity fit tightly to complete the sealing of the vacuum space in the cavity, and the sealing pressure between the sealing piston and the cavity is increased, thereby improving the airtightness between the joint surfaces of the two.

[0079] like Fig.16 As shown, in Example 14, a sealing ring is provided between the sealing piston and the inner wall of the cavity, and the sealing ring is made of an elastic or flexible porous material. The porous material can be any one of polymer sponge, foam plastic, and rubber sponge, preferably a closed-cell material, that is, a plurality of closed air chambers are formed in the porous material, and the sealing piston itself is a rigid material or an elastic material, and the sealing pressure between the sealing ring and the inner wall of the cavity is greater than or equal to zero; when the cavity is evacuated, each air chamber in the porous material deforms and expands under the action of the pressure difference, thereby causing the sealing ring to expand as a whole, thereby improving the sealing degree between the sealing ring and the inner wall of the cavity.

[0080] like Fig.17As shown, in Example 15, a sealing ring is provided between the sealing piston 9 and the inner wall of the cavity 2. The sealing ring is a hollow sealing ring 10, which has at least one air chamber 3 therein, and the air chamber is closed or connected to the external environment; in the case of a single air chamber, the air chamber can be set to match the shape of the sealing ring, and in the case of multiple air chambers, each air chamber is independent and evenly distributed in the sealing ring to improve the uniformity of the expansion deformation of the sealing ring when the cavity is evacuated, and the air chamber is closed or connected to the external environment. When the cavity is evacuated, the cavity generates a vacuum negative pressure relative to each air chamber, and the air chamber expands and deforms, causing the sealing ring to deform as a whole, thereby improving the sliding sealing performance between the sealing piston and the cavity. When the ambient air pressure is restored in the cavity, the pressure condition between the air chamber and the cavity is restored to the initial state, the volume of the hollow sealing ring is reduced, and the bonding force between the sealing piston and the cavity is reduced, thereby facilitating the removal of the sealing piston from the barrel.

[0081] like Fig.18 , Fig.19 As shown, in Example 16, an annular sealing belt 5 is provided between the side wall of the sealing piston 9 and the inner side wall of the cavity 2, and an air guide hole 6 is provided on the side wall of the sealing piston. When the sealing piston slides and seals the cavity, one end of the air guide hole is connected to the external environment outside the cavity, and the other end of the air guide hole is covered by the annular sealing belt. The annular sealing belt provided on the sealing piston has a small sealing pressure on the inner side wall of the cavity in the initial state or there is no sealing pressure. When the space between the sealing piston and the cavity is evacuated, a pressure difference is generated between the side of the annular sealing belt connected to the external environment and the side in contact with the vacuum negative pressure cavity, and the difference is the difference between the ambient air pressure and the vacuum negative pressure in the cavity. Under the action of the pressure difference, the annular sealing belt deforms from the external environment side to the side in the cavity, and the sealing pressure on the sealing surface between the sealing belt and the inner side wall of the cavity increases or changes from non-contact to forming a sealing surface, thereby improving the sealing degree of the internal space of the cavity. When the ambient air pressure in the cavity is restored, the annular sealing belt returns to its initial state. An annular deformation band 7 is arranged in the middle of the band wall of the annular sealing band, and preferably, the upper and lower ends are respectively fixed to the side walls of the sealing piston; an annular groove 8 is arranged in the band wall of the annular sealing band in the present figure, and in actual use, an annular groove can be arranged on at least one side of the side wall of the sealing piston or the band wall of the annular sealing band to increase the air circulation area, and the position of the annular groove corresponds to the position of the deformation band on the band wall of the annular sealing band, and the deformation groove is connected to the air guide hole.

[0082] like Fig. 20As shown, in Example 17, a hollow sealing ring 10 with a hollow air chamber is provided between the side wall of the sealing piston 9 and the inner side wall of the cavity 2, at least one air chamber 3 is provided in the hollow sealing ring, and an air guide hole is provided on the side wall of the sealing piston. When the sealing piston slides and seals the cavity, one end of the air guide hole is connected with the external environment of the cavity, and the other end of the air guide hole is covered by the hollow sealing ring. The air chamber in the hollow sealing ring is closed or the air chamber is connected with the external environment through the air guide hole; when the cavity is evacuated, a pressure difference is formed between the air pressure in the air chamber in the hollow sealing ring and the air pressure in the cavity, and the air chamber expands and deforms toward the inside of the cavity, thereby increasing the sealing pressure corresponding to the sealing surface between the hollow sealing ring and the inner side wall of the cavity, thereby improving the sealing degree.

[0083] like Fig.21 As shown, in Example 18, a porous material sealing ring 4 is provided between the side wall of the sealing piston 9 and the inner wall of the cavity 2. The porous material can be any one of polymer sponge, foam plastic, and rubber sponge, preferably a closed-cell material, that is, a plurality of closed air chambers 3 are formed in the porous material, and an air guide hole 6 is provided on the side wall of the sealing piston. When the sealing piston slides and seals the cavity, one end of the air guide hole is connected to the external environment, and the other end of the air guide hole is covered by the porous material sealing ring; when the cavity is evacuated, a pressure difference is generated between the air pressure in the air chamber in the porous material sealing ring and the air pressure in the cavity, and the expansion of the air chamber drives the porous material sealing ring to expand and deform. At the same time, the porous material sealing ring also expands and deforms toward the inner wall of the cavity under the action of the pressure difference between the ambient air pressure on one side and the vacuum negative pressure in the cavity, thereby increasing the sealing pressure on the sealing surface of the inner wall of the cavity and improving the air density.

[0084] In the sealing cover and sealing ring structure made of the above-mentioned porous material, a wear-resistant layer is preferably coated outside the porous material. The cover wear-resistant layer is made of elastic material such as silicone material. While ensuring that the sealing cover and the sealing ring are in close contact with the sealing surface, the wear resistance of the corresponding components is improved, thereby extending the overall service life of the sealing structure.

[0085] The negative pressure sealing method of the present invention comprises the following steps:

[0086] A. The sealing body seals the cavity under ambient pressure, and the sealing pressure between the sealing body and the sealing surface of the cavity is the initial pressure, which is greater than or equal to zero, wherein the sealing body is a sealing cover, a sealing piston, or a sealing cover or a sealing piston with a sealing ring;

[0087] B. Evacuate the cavity to generate a vacuum negative pressure inside the cavity, the sealing body deforms under the vacuum negative pressure, and the sealing pressure between the sealing body and the sealing surface of the cavity is greater than the initial pressure;

[0088] C. The vacuum negative pressure in the cavity reaches a set value, the sealing pressure between the sealing body and the sealing surface of the cavity reaches a maximum value, and the sealing degree between the sealing body and the cavity is improved;

[0089] D. When it is necessary to open and obtain the sealing body, the vacuum state in the cavity is released, the deformation of the sealing body is restored to the initial state, and the sealing pressure between the sealing body and the sealing surface of the cavity is restored to the initial pressure;

[0090] E. Separate the sealing body from the cavity.

[0091] The vacuum food processor is an application of the negative pressure sealing structure of the present invention, wherein the vacuum food processor of the present invention includes a barrel body and a cutter disc body, the barrel body and the cutter disc body are connected, the barrel body is equivalent to a cavity, and the cutter disc body is equivalent to a sealing cover, a sealing ring is arranged between the barrel body and the cutter disc body, the sealing ring is a porous material sealing ring or a hollow sealing ring, when the barrel body and the cutter disc body are connected under ambient air pressure, the sealing pressure of the barrel body and the cutter disc body on the sealing ring is an initial pressure, and the initial pressure is greater than zero; when a vacuum negative pressure state is formed inside the barrel body, the sealing pressure of the barrel body and the cutter disc body on the sealing ring is greater than the initial pressure, and the sealing surface between the barrel body and the cutter disc body is at the bottom and side wall of the barrel body.

[0092] The negative pressure sealing structure of the present invention is applied to a vacuum food processor. The vacuum food processor comprises a sealing cover and a barrel body, and the cavity is the barrel body.

[0093] The negative pressure sealing structure of the present invention is used in a vacuum press. The vacuum press comprises a pressing cylinder and a sealing piston, and the cavity is the pressing cylinder.

[0094] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession will, without departing from the scope of the technical solution of the present invention, certainly make some changes or modifications using the disclosed technical content to become an equivalent embodiment of equivalent changes. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are within the scope of the technical solution of the present invention.

Claims

1. A negative pressure sealing structure, comprising a sealing body and a cavity, wherein the sealing body is used to seal the cavity, and the sealing body is a passive negative pressure deformation sealing structure. When the sealing body seals the cavity under ambient pressure, the sealing pressure between the sealing body and the sealing surface of the cavity is an initial pressure, and the initial pressure is greater than or equal to zero; when a vacuum negative pressure state is formed inside the cavity, the sealing body is deformed under the vacuum negative pressure, so that the sealing pressure between the sealing body and the sealing surface of the cavity is greater than the initial pressure, and the sealing degree between the sealing body and the cavity is improved, characterized in that: The sealing body is a sealing cover, the sealing surface of the cavity is a contact surface between the sealing cover and the side wall of the cavity, and the sealing cover is one of the following structures: ①The sealing cover is made of elastic or flexible porous material; ② A sealing ring is provided between the sealing cover and the side wall of the cavity, and the sealing ring is made of an elastic or flexible porous material; ③ The sealing cover includes a top and a side wall. The side wall of the sealing cover is inserted into the cavity or covered outside the cavity. A porous material sealing ring is provided between the side wall of the sealing cover and the side wall of the cavity. There is an air guide hole penetrating the side wall of the sealing cover. When the sealing cover seals the cavity, one end of the air guide hole is connected to the external environment, and the other end of the air guide hole is covered by the porous material sealing ring; A plurality of closed independent air chambers are formed in the porous material, and a wear-resistant layer is coated outside the porous material.

2. A negative pressure sealing structure, comprising a sealing body and a cavity, wherein the sealing body is used to seal the cavity, and the sealing body is a passive negative pressure deformation sealing structure. When the sealing body seals the cavity under ambient pressure, the sealing pressure between the sealing body and the sealing surface of the cavity is an initial pressure, and the initial pressure is greater than or equal to zero; when a vacuum negative pressure state is formed inside the cavity, the sealing body is deformed under the vacuum negative pressure, so that the sealing pressure between the sealing body and the sealing surface of the cavity is greater than the initial pressure, and the sealing degree between the sealing body and the cavity is improved, characterized in that: The sealing body is a sealing piston disposed in the cavity, the sealing surface of the cavity is the contact surface between the sealing piston and the inner wall of the cavity, and the sealing piston is one of the following structures: ⑴The sealing piston is made of elastic or flexible porous material; (2) A sealing ring is provided between the sealing piston and the inner wall of the cavity, and the sealing ring is made of an elastic or flexible porous material; (3) A porous material sealing ring is provided between the side wall of the sealing piston and the inner wall of the cavity, and an air guide hole is provided on the side wall of the sealing piston. When the sealing piston slides and seals the cavity, one end of the air guide hole is connected to the external environment, and the other end of the air guide hole is covered by the porous material sealing ring; A plurality of closed independent air chambers are formed in the porous material, and a wear-resistant layer is coated outside the porous material.

3. A negative pressure sealing method, characterized in that: The following steps are involved: A. The sealing body seals the cavity under ambient pressure, and the sealing pressure between the sealing body and the sealing surface of the cavity is the initial pressure, which is greater than or equal to zero; B. Evacuate the cavity to generate a vacuum negative pressure inside the cavity, the sealing body deforms under the vacuum negative pressure, and the sealing pressure between the sealing body and the sealing surface of the cavity is greater than the initial pressure; C. The vacuum negative pressure in the cavity reaches a set value, the sealing pressure between the sealing body and the sealing surface of the cavity reaches a maximum value, and the sealing degree between the sealing body and the cavity is improved; D. When the sealing body needs to be opened or removed, the vacuum state in the cavity is released, the deformation of the sealing body is restored to the initial state, and the sealing pressure between the sealing body and the sealing surface of the cavity is restored to the initial pressure; E. Separate the sealing body from the cavity.

4. An application of the negative pressure sealing structure according to claim 1 in a vacuum food processor, wherein the vacuum food processor comprises a sealing cover and a barrel body, and the cavity is the barrel body.

5. An application of the negative pressure sealing structure according to claim 2 in a vacuum press, wherein the vacuum press comprises a pressing cylinder and a sealing piston, and the cavity is the pressing cylinder.

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