Double-seal brewing structure of coffee machine

Abstract

The invention provides a coffee machine double-seal brewing structure which comprises a brewing barrel, a front piston assembly and a rear piston assembly, the front piston assembly and the rear piston assembly are arranged at the front end and the rear end of the brewing barrel, the front piston assembly comprises a front piston, the rear end of the front piston is of a disc-shaped structure, the front end of the front piston is of a rod-shaped structure, and the rear end of the disc-shaped structure of the front piston is sleeved with a Y-shaped sealing ring; and an O-shaped sealing ring is nested on the side surface. A dual-sealing mode is adopted to replace an original piston in an independent sealing mode, when the brewing device works, pressure is dispersed on the two sealing rings, the Y-shaped sealing ring with the small interference size is adopted at the front end to mainly prevent powder residues in coffee liquid from leaking, when part of the coffee liquid reaches the back, the O-shaped sealing ring is used for blocking, and the sealing effect is good. Therefore, the problem of friction force during reciprocating motion of the Y-shaped sealing ring with a large interference size is avoided, coffee powder is blocked, meanwhile, the working pressure of the O-shaped sealing ring at the rear end is dispersed, and the risk of liquid leakage after a single sealing ring fails is solved.

Description

Technical Field

[0001] The invention relates to the technical field of fully automatic coffee machines, and in particular to a double-sealed brewing structure of a coffee machine. Background Art

[0002] At present, in the traditional fully automatic coffee machine brewing system, the piston sealing method adopts a separate Y-ring or O-ring sealing method.

[0003] If the Y-shaped sealing ring is used alone, this independent sealing method requires a very tight fit in order to ensure the sealing effect. This will increase the friction during the operation of the brewer due to the thermal expansion of the material and the increased friction coefficient of the coffee powder. After a period of operation, the Y-shaped sealing ring will be deformed and the flange will fail due to pressure, and the brewing tube will also be worn out faster, shortening its life.

[0004] If the O-ring is used alone, the coffee liquid will enter the groove of the O-ring due to the pressure during the coffee extraction process. Over time, the coffee powder in the coffee liquid will accumulate in the groove of the O-ring. The accumulated coffee powder in the sealing groove will reduce the compression space of the O-ring. In serious cases, the O-ring will be stretched, increasing the resistance of the piston entering the brewing cylinder, or it will be unable to enter the brewing cylinder, causing the O-ring to twist and break or be sheared and broken by the brewing cylinder and fail. This seriously affects the life and maintenance cost of the brewing module in the fully automatic coffee machine.

[0005] In addition, the existing patent [CN118161064A-Fully automatic coffee machine brewer pressure system], the description mentions that "the upper bracket and the lower bracket of the hydraulic extraction head assembly are provided with a hydraulic upper seat and a hydraulic lower seat which are integrated into a sealing sleeve, and a Y-type sealing ring is provided at the sleeve" and "the outer diameter of the extraction head is provided with an O-type sealing ring". Although it contains a Y-type sealing ring and an O-type sealing ring, it does not combine the two to achieve the effect of dispersing pressure and extending life, and the two sealing rings only realize the corresponding sealing function respectively, which is completely different from the scheme reported in this application in terms of effect and function. Summary of the invention

[0006] To solve the above problems, the present invention discloses a double-sealed brewing structure for a coffee machine, which combines the advantages of two sealing rings, so that a Y-shaped sealing ring and an O-shaped sealing ring are installed on the piston at the same time, and adopts a uniquely designed sealing method with the Y-shaped sealing ring at the front end and the O-shaped sealing ring at the rear end.

[0007] The specific plan is as follows: A dual-sealed brewing structure for a coffee machine, characterized in that: it includes a brewing cylinder and a front piston assembly and a rear piston assembly arranged at the front and rear ends of the brewing cylinder. The brewing cylinder serves as a working cavity for coffee powder brewing and extraction. The front piston assembly includes a front piston for extruding the coffee powder cake and having a coffee liquid outlet channel in the middle. The rear end of the front piston is a disc-shaped structure adapted to the inner cavity of the brewing cylinder, and the front end is a rod-shaped structure. A Y-shaped sealing ring is sleeved at the rear end of the disc-shaped structure of the front piston, and an O-shaped sealing ring is nested on the side. The Y-shaped sealing ring is used to block coffee powder residue and reduce the working pressure of the front O-shaped sealing ring. The O-shaped sealing ring is used to prevent coffee liquid leakage.

[0008] Further, the Y-shaped sealing ring is a polyurethane sealing ring, and the O-shaped sealing ring is a fluororubber sealing ring.

[0009] Further, the coffee liquid outlet channel of the front piston includes a trumpet section arranged in the disc-shaped structure of the front piston and a straight section arranged in the rod-shaped structure of the front piston rod. Among them, the trumpet section is smaller at the front and larger at the rear. The Y-shaped sealing ring is placed at the rear end opening of the trumpet section, and a front filter screen is provided between the Y-shaped sealing ring and the rear end opening of the trumpet section.

[0010] Further, the rear piston assembly includes a rear piston and a rear piston rod arranged front and rear. The rear piston is used to evenly distribute the hot water for extracting coffee and prevent coffee powder residue from entering the rear piston rod when squeezing the coffee powder. The rear piston is a disc-shaped structure adapted to the inner cavity of the brewing cylinder and is installed on the front end face of the rear piston rod. The rear piston rod is used to provide powder discharging support and has a water inlet channel in the middle. Its front end is a disc-shaped structure and the rear end is a rod-shaped structure.

[0011] Further, a rear filter screen is installed on the front end face of the rear piston through a filter screen sleeve.

[0012] Further, an end face sealing ring is provided on the rear side of the disc-shaped structure of the rear piston rod for sealing when the rear piston assembly extracts coffee liquid.

[0013] Further, the front end of the brewing cylinder is open, and the rear end is a ring-shaped structure with a through hole in the middle. The rear rod-shaped structure of the rear piston rod can slide back and forth in the rear through hole of the brewing cylinder.

[0014] Further, the coffee brewing and extraction steps are as follows: S1. The brewing cylinder and the front piston assembly are in a separated state, and coffee powder is squeezed into the brewing cylinder by a coffee grinding mechanism; S2. The brewing cylinder drives the rear piston assembly to move towards the front piston assembly. When the front piston assembly enters the brewing cylinder, the loose coffee powder in the brewing cylinder is continuously compressed until the coffee powder is compressed into a compact coffee powder cake; S3. The boiling water flowing into the rear piston assembly is injected into the coffee powder cake. At this time, with the operation of the water pump in the brewing cylinder, the pressure becomes greater and greater. Due to the sealing effect of the end face sealing ring of the rear piston assembly, the Y-shaped sealing ring and the O-shaped sealing ring of the front piston assembly, the coffee grounds are blocked in the brewing cylinder by the Y-shaped sealing ring. A small amount of coffee liquid flows into the O-shaped sealing ring of the front piston assembly through the tiny gap between the Y-shaped sealing ring and the inner wall of the brewing cylinder. At this time, the pressure of this part of the coffee liquid has been greatly reduced by the Y-shaped sealing ring. The O-shaped sealing ring plays a sealing role under the condition of bearing a smaller working force. The extracted coffee liquid can only flow out of the inner channel of the front piston through the front filter screen, completing the extraction of the coffee liquid; S4. After the extraction is completed, the brewing cylinder drives the rear piston assembly to move in the opposite direction of the front piston assembly until the rear piston assembly is limited by the limiting mechanism. The brewing cylinder continues to move backward, and the rear piston assembly pushes out the coffee grounds, completing the coffee brewing and extraction process.

[0015] The present invention uses a double-sealing method to replace the original piston with an independent sealing method, so that the pressure during the operation of the brewer is dispersed on the two sealing rings. The Y-shaped sealing ring with a small interference fit size is mainly used at the front end to prevent the powder residue in the coffee liquid from leaking. When part of the coffee liquid reaches the back, it is blocked by the O-shaped sealing ring. In this way, it not only avoids the problem of friction force during the reciprocating movement of the Y-shaped sealing ring with a large interference fit size, but also blocks the coffee powder. At the same time, it disperses the working pressure of the O-shaped seal at the back end and solves the risk of liquid leakage after the failure of a single sealing ring.

[0016] The beneficial effects of the present invention are as follows: 1. The Y-shaped sealing ring and the O-shaped seal are combined together to disperse the working pressure and friction coefficient of the two parts. The high-hardness Y-shaped polyurethane sealing ring and the medium-hardness fluororubber sealing ring form a double-sealing structure that combines rigidity and flexibility, reducing the control requirements for the part size, improving the sealing effect, and giving full play to the excellent properties of the two materials (the high water tightness of fluororubber makes up for the low water tightness of polyurethane, ensuring the water tightness; the high hardness of polyurethane makes up for the medium hardness of fluororubber, ensuring the rigidity of the fixed filter screen), and prolonging the working life of the brewing system.

[0017] 2. The double-sealing guarantee not only ensures a reliable sealing effect, prolongs the maintenance cycle of the sealing ring wear parts, but also greatly reduces the maintenance cost and the failure rate of the product. Brief Description of the Drawings

[0018] Figure 1 is a schematic structural diagram of the present invention.

[0019] Figure 2 is a schematic structural diagram of the front piston assembly in the present invention.

[0020] List of Reference Numerals: 1 - Brewing cylinder, 2 - Front piston, 3 - Y - type sealing ring, 4 - O - type sealing ring, 5 - Rear filter screen, 6 - Rear piston, 7 - Rear piston rod, 8 - Filter screen sleeve, 9 - End face sealing ring, 10 - Front filter screen. Detailed implementation mode

[0021] The following further clarifies the present invention in conjunction with the accompanying drawings and the detailed implementation mode. It should be understood that the following detailed implementation mode is only used to illustrate the present invention and not to limit the scope of the present invention.

[0022] As shown in the figure, the present invention provides a double - sealed brewing structure for a coffee machine, including a brewing cylinder (1) and a front piston assembly and a rear piston assembly arranged at the front and rear ends of the brewing cylinder (1). The brewing cylinder (1) serves as a working cavity for brewing and extracting coffee powder. The front piston assembly includes a front piston (2) for extruding the coffee powder cake and having a coffee liquid outlet channel in the middle. The rear end of the front piston (2) is a disc - shaped structure adapted to the inner cavity of the brewing cylinder (1), and the front end is a rod - shaped structure. A Y - type sealing ring (3) is sleeved at the rear end of the disc - shaped structure of the front piston (2), and an O - type sealing ring (4) is nested on the side. The Y - type sealing ring (3) is used to block coffee powder residue and reduce the working pressure of the front O - type sealing ring (4), and the O - type sealing ring (4) is used to prevent coffee liquid leakage and ensure the seal in the brewing cavity.

[0023] In this embodiment, the Y - type sealing ring (3) is a polyurethane sealing ring, and the O - type sealing ring is a fluororubber sealing ring.

[0024] In this embodiment, the coffee liquid outlet channel of the front piston (2) includes a trumpet section arranged in the disc - shaped structure of the front piston (2) and a straight section arranged in the rod - shaped structure of the front piston (2). Among them, the trumpet section is smaller at the front and larger at the rear. The Y - type sealing ring (3) is placed at the rear - end opening of the trumpet section, and a front filter screen (10) is arranged between the Y - type sealing ring (3) and the rear - end opening of the trumpet section. When extracting coffee, it can filter coffee powder residue.

[0025] In this embodiment, the rear piston assembly includes a rear piston (6) and a rear piston rod (7) arranged front - to - rear. The rear piston (6) is used to evenly distribute the hot water for extracting coffee and prevent coffee residue from entering the rear piston rod (7) when squeezing the coffee powder. The rear piston (6) is a disc - shaped structure adapted to the inner cavity of the brewing cylinder (1) and is installed on the front end face of the rear piston rod (7). The rear piston rod (7) is used to provide powder - discharging support and has a water inlet channel in the middle. Its front end is a disc - shaped structure, and the rear end is a rod - shaped structure.

[0026] In this embodiment, a rear filter screen (5) is installed on the front end face of the rear piston (6) through a filter screen sleeve (8).

[0027] In this embodiment, an end face seal ring (9) is provided at the rear side of the disc-shaped structure of the rear piston rod (7) for sealing when the rear piston assembly extracts coffee liquid.

[0028] In this embodiment, the front end of the brewing cylinder (1) is open, and the rear end is a ring-shaped structure with a through hole in the middle. The rear rod-shaped structure of the rear piston rod (7) can slide back and forth in the through hole at the rear end of the brewing cylinder (1).

[0029] In this embodiment, the coffee brewing and extraction steps are as follows: S1. The brewing cylinder (1) and the front piston assembly are in a separated state, and coffee powder is squeezed into the brewing cylinder by the coffee grinding mechanism. S2. The brewing cylinder (1) drives the rear piston assembly to move towards the front piston assembly. When the front piston assembly enters the brewing cylinder (1), the loose coffee powder in the brewing cylinder (1) is continuously compressed until the coffee powder is compressed into a compact coffee powder cake. S3. Boiling water flowing into the rear piston assembly is injected into the coffee powder cake. At this time, with the operation of the water pump in the brewing cylinder (1), the pressure becomes greater and greater. Due to the sealing effects of the end face seal ring (9) of the rear piston assembly, the Y-shaped seal ring (3) and the O-shaped seal ring (4) of the front piston assembly, the coffee powder residue is blocked by the Y-shaped seal ring (3) in the brewing cylinder (1). A small amount of coffee liquid flows into the O-shaped seal ring (4) of the front piston assembly through the tiny gap between the Y-shaped seal ring (3) and the inner wall of the brewing cylinder (1). At this time, the pressure of this part of the coffee liquid has been greatly reduced by the Y-shaped seal ring. The O-shaped seal ring plays a sealing role under a smaller working force, and the extracted coffee liquid can only flow out through the front filter screen (10) into the internal channel of the front piston to complete the extraction of the coffee liquid. S4. After the extraction is completed, the brewing cylinder (1) drives the rear piston assembly to move in the opposite direction of the front piston assembly until the rear piston assembly is limited by the limiting mechanism. The brewing cylinder (1) continues to move backward, and the rear piston assembly pushes out the coffee powder residue to complete a coffee brewing and extraction process.

[0030] The present invention uses a double-sealing method to replace the original piston with an independent sealing method, so that the pressure during the operation of the brewer is dispersed on the two seal rings. The Y-shaped seal ring with a small interference fit size at the front end mainly prevents the powder residue in the coffee liquid from leaking. When part of the coffee liquid reaches the back, it is blocked by the O-shaped seal ring. In this way, it not only avoids the problem of friction during the reciprocating movement of the Y-shaped seal ring with a large interference fit size, but also blocks the coffee powder, while dispersing the working pressure of the O-shaped seal at the back end, and also solves the risk of liquid leakage after the failure of a single seal ring.

[0031] The technical means disclosed in the solution of the present invention are not limited to the technical means disclosed in the above embodiments, but also include technical solutions composed of any combination of the above technical features. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements are also regarded as the protection scope of the present invention.

Claims

1. A double-sealed brewing structure for a coffee machine, characterized in that: It includes a brewing cylinder (1), a front piston assembly and a rear piston assembly provided at the front and rear ends of the brewing cylinder (1). The brewing cylinder (1) serves as a working cavity for coffee powder brewing and extraction. The front piston assembly includes a front piston (2) for extruding the coffee powder cake and having a coffee liquid outlet channel in the middle. The rear end of the front piston (2) is a disc-shaped structure adapted to the inner cavity of the brewing cylinder (1), and the front end is a rod-shaped structure. A Y-shaped sealing ring (3) is sleeved on the rear end of the disc-shaped structure of the front piston (2), and an O-shaped sealing ring (4) is nested on the side. The Y-shaped sealing ring (3) is used to block coffee powder residue and reduce the working pressure of the front O-shaped sealing ring (4), and the O-shaped sealing ring (4) is used to prevent coffee liquid leakage.

2. The double-sealed brewing structure of a coffee machine according to claim 1, wherein: The Y-shaped sealing ring (3) is a polyurethane sealing ring, and the O-shaped sealing ring (3) is a fluororubber sealing ring.

3. The double-sealed brewing structure of a coffee machine according to claim 1, wherein: The coffee liquid outlet channel of the front piston (2) includes a trumpet section provided in the disc-shaped structure of the front piston (2) and a straight section provided in the rod-shaped structure of the front piston (2). Among them, the trumpet section is smaller at the front and larger at the rear. The Y-shaped sealing ring (3) is placed at the rear end opening of the trumpet section, and a front filter screen (10) is provided between the Y-shaped sealing ring (3) and the rear end opening of the trumpet section.

4. A dual-sealing brewing structure of a coffee machine according to claim 1, characterized in that: The rear piston assembly includes a rear piston (6) and a rear piston rod (7) arranged front and rear. The rear piston (6) is used to evenly distribute the hot water for extracting coffee and prevent coffee residue from entering the rear piston rod (7) when extruding the coffee powder. The rear piston (6) is a disc-shaped structure adapted to the inner cavity of the brewing cylinder (1) and is installed on the front end face of the rear piston rod (7). The rear piston rod (7) is used to provide powder ejection support and has a water inlet channel in the middle. Its front end is a disc-shaped structure, and the rear end is a rod-shaped structure.

5. The double-sealed brewing structure of a coffee machine according to claim 4, characterized in that: A rear filter screen (5) is installed on the front end face of the rear piston (6) through a filter screen sleeve (8).

6. The double-sealed brewing structure of a coffee machine according to claim 4, characterized in that: An end face sealing ring (9) is provided on the rear side of the disc-shaped structure of the rear piston rod (7) for sealing when the rear piston assembly extracts coffee liquid.

7. A dual-sealing brewing structure of a coffee machine according to claim 4, characterized in that: The front end of the brewing cylinder (1) is open, and the rear end is an annular structure with a through hole in the middle. The rear rod-shaped structure of the rear piston rod (7) can slide back and forth in the rear through hole of the brewing cylinder (1).

8. A double-sealed brewing structure for a coffee machine according to any one of claims 1-7, characterized in that: The steps of coffee brewing and extraction are as follows: S1. The brewing cylinder (1) and the front piston assembly are in a separated state, and coffee powder is squeezed into the brewing cylinder by a coffee grinding mechanism. S2. The brewing cylinder (1) drives the rear piston assembly to move towards the front piston assembly. After the front piston assembly enters the brewing cylinder (1), the loose coffee powder in the brewing cylinder (1) is continuously compressed until the coffee powder is compressed into a compact coffee powder cake. S3. The boiling water flowing into the rear piston assembly is injected into the coffee powder cake. At this time, with the operation of the water pump in the brewing cylinder (1), the pressure becomes greater and greater. Due to the sealing effect of the end face sealing ring (9) of the rear piston assembly, the Y-shaped sealing ring (3) and the O-ring (4) of the front piston assembly, the coffee grounds are blocked by the Y-shaped sealing ring (3) in the brewing cylinder (1). Among them, a small amount of coffee liquid flows into the O-ring (4) of the front piston assembly through the tiny gap between the Y-shaped sealing ring (3) and the inner wall of the brewing cylinder (1). Due to the sealing effect of the O-ring (4), the extracted coffee liquid can only flow out of the inner channel of the front piston through the front filter screen (10), completing the extraction of the coffee liquid; S4. After the extraction is completed, the brewing cylinder (1) drives the rear piston assembly to move in the opposite direction of the front piston assembly until the rear piston assembly is limited by the limiting mechanism. The brewing cylinder (1) continues to move backward, and the rear piston assembly pushes out the coffee grounds, completing a coffee brewing and extraction process.

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