COFFEE MACHINE AND WORKING METHOD THEREFOR

Abstract

A coffee machine with a leak preventing device includes a main body, a first lid body, a brewing chamber, a water tank and a heating device, the brewing chamber. The water tank and the heating device are provided in the main body. The main body is provided with a main body opening, and the first lid body is used for covering the main body opening. The coffee machine further comprises a flow guiding device. The flow guiding device comprises a first flow guiding channel, a first end of the first flow guiding channel being connected to the heating device, the brewing chamber being provided with a brewing chamber through hole corresponding to a second end of the first flow guiding channel, the second end of the first flow guiding channel being inserted into the brewing chamber through the brewing chamber through hole. A working method is also provided.

Claims

1. A coffee machine, comprising a main body (1), a first lid body (6), a brewing chamber (412), a water tank (2) and a heating device (3), the brewing chamber (412), the water tank (2) and the heating device (3) being provided in the main body (1), the main body (1) being provided with a main body opening, wherein the first lid body (6) is used for covering the main body opening, the coffee machine further comprises a flow guiding device, wherein the flow guiding device comprises a first flow guiding channel (51), a first end (511) of the first flow guiding channel (51) being connected to the heating device (3), the brewing chamber (412) being provided with a brewing chamber through hole corresponding to a second end (512) of the first flow guiding channel (51), the second end (512) of the first flow guiding channel (51) being inserted into the brewing chamber (412) through the brewing chamber through hole; or wherein the flow guiding device comprises the first flow guiding channel (51) and a second flow guiding channel (52) detachably connected to the first flow guiding channel (51), the first end (511) of the first flow guiding channel (51) being connected to the heating device (3), the first lid body (6) being provided with the second flow guiding channel (52) which has a water inlet (524) and a water outlet (525), the water outlet (525) being located at a position corresponding to a brewing chamber opening (416) such that liquid is supplied to the brewing chamber (412).

2. The coffee machine according to claim 1, wherein the second flow guiding channel (52) is an individual member provided on the first lid body (6).

3. The coffee machine according to claim 1, wherein the second flow guiding channel (52) is partially or totally formed by the first lid body (6).

4. The coffee machine according to claim 1, wherein a cavity (523), which is provided with the water inlet (524) and the water outlet (525), is provided inside the first lid body (6), the water inlet (524) being fluidly communicated to the water outlet (525) so as to form the second flow guiding channel (52), the second end (512) of the first flow guiding channel (51) being detachably connected to the water inlet (524), the water outlet (525) being located at a position corresponding to the brewing chamber opening (416) such that liquid is supplied to the brewing chamber (412).

5. The coffee machine according to claim 1, wherein a cavity (523), which is provided with the water outlet (525), is provided inside the first lid body (6), the second flow guiding channel (52) comprises a first pipe portion (521) which is connected to the cavity (523) and provided with the water inlet (524), the water inlet (524) being fluidly communicated to the water outlet (525) so as to form the second flow guiding channel (52), the second end (512) of the first flow guiding channel (51) being detachably connected to the water inlet (524) of the first pipe portion (521), the water outlet (525) of the cavity (523) being located at a position corresponding to the brewing chamber opening (416) such that liquid is supplied to the brewing chamber (412).

6. The coffee machine according to claim 1, wherein a cavity (523) is provided inside the first lid body (6), the second flow guiding channel (52) comprises a first pipe portion (521) provided with the water inlet (524) and a second pipe portion (522) provided with the water outlet (525), the water inlet (524) and the water outlet (525) being fluidly communicated to the cavity (523) respectively so as to form the second flow guiding channel (52), the second end (512) of the first flow guiding channel (51) being detachably connected to the water inlet (524) of the first pipe portion (521), the water outlet (525) of the second pipe portion (522) being located at a position corresponding to the brewing chamber opening (416) such that liquid is supplied to the brewing chamber (412).

7. The coffee machine according claim 4, wherein the first lid body (6) is detachably engaged with the main body (1), and the first lid body (6) comprises a first upper lid body (61) and a first lower lid body (62), the first upper lid body (61) being engaged with the first lower lid body (62) so as to form the cavity (523).

8. The coffee machine according claim 4, wherein a cavity channel (526) is provided inside the cavity (523), the water inlet (524) and the water outlet (525) being fluidly communicated to the cavity channel (526) respectively so as to form the second flow guiding channel (52).

9. The coffee machine according to claim 1, wherein the water inlet (524) is detachably connected to the second end (512) of the first flow guiding channel (51) inside the main body (1), and the coffee machine further comprises a blocking device provided at a position corresponding to the second end (512) of the first flow guiding channel (51), such that the blocking device is capable of being deformed to prevent liquid from being ejected out of the main body opening when the second flow guiding channel (52) is detached from the first flow guiding channel (51).

10. The coffee machine according to claim 9, wherein the blocking device is an elastic assembly, a first end of the elastic assembly being elastically provided at a position corresponding to the second end (512) of the first flow guiding channel (51), a second end of the elastic assembly being capable of being rotated around the first end of the elastic assembly such that the elastic assembly is deformed.

11. The coffee machine according to claim 9, wherein the blocking device is an elastic single piece (72), a middle portion of the elastic single piece (72) being provided with at least one cutout (721), the elastic single piece (72) being capable of being deformed by extrusion such that the cutout (721) is opened.

12. The coffee machine according to claim 9, wherein a backflow channel (21) is provided inside the main body (1), the backflow channel (21) being communicated to an upper portion of the water tank (2) and the first flow guiding channel (51) respectively, such that at least a part of liquid blocked by the blocking device enters into the backflow channel (21) and flows into the water tank (2) when the second flow guiding channel (52) is detached from the first flow guiding channel (51).

13. The coffee machine according to claim 1, wherein the water inlet (524) is detachably connected to the second end (512) of the first flow guiding channel (51) inside the main body (1), the second end (512) of the first flow guiding channel (51) having a closed top is disposed over the first pipe portion (521) of the second flow guiding channel (52), a side wall of the second end (512) of the first flow guiding channel (51) being provided with a side wall outlet (514), a gap being provided between the side wall outlet (514) and the first pipe portion (521), such that liquid flows from the side wall outlet (514) into the second flow guiding channel (52).

14. The coffee machine according to claim 13, wherein a backflow channel (21) is provided inside the main body (1), the backflow channel (21) being communicated to an upper portion of the water tank (2) and the first flow guiding channel (51) respectively, such that at least a part of liquid which flowed from the side wall outlet (514) enters into the backflow channel (21) and flows into the water tank (2) when the second flow guiding channel (52) is detached from the first flow guiding channel (51).

15. The coffee machine according to claim 1, wherein a fixing element for fixing the first lid body (6) onto the main body (1) is provided on the first lid body (6) and/or the main body (1), and a second lid body (63) for covering the brewing chamber opening (416) is provided on a lower side of the first lid body (6), an elastic member (633) being provided between the first lid body (6) and the second lid body (63), such that a relative seal is formed between the second lid body (63) and the brewing chamber (412) when the first lid body (6) is fixed onto the main body (1).

16. The coffee machine according to claim 1, wherein the coffee machine further comprises a grinding and filtering device which comprises a chamber (41) for containing liquid and coffee particles, a grinding assembly for grinding coffee particles, a driving mechanism (43) connected to the grinding assembly and for driving the grinding assembly, and a first filter (44) for filtering coffee liquid in the chamber (41); wherein the chamber (41) is provided with a chamber opening, and at least a part of the grinding assembly is placed in the chamber (41), the chamber (41) comprising the brewing chamber (412) provided with the brewing chamber opening (416), and a liquid channel (411) communicated with the brewing chamber (412) being located on a bottom of the brewing chamber (412), the first filter (44) being partially or totally located on the bottom of the brewing chamber (412), the liquid channel (411) being located on a lower side of the first filter (44) such that coffee liquid in the brewing chamber (412) flows through the first filter (44) before entering the liquid channel (411).

17. A working method for the coffee machine according to claim 1, comprising: a. adding liquid into the water tank (2), and adding coffee powder into the chamber (412); b. transferring liquid into the heating device (3) from the water tank (2), heating liquid by the heating device (3); c. transferring heated liquid into the brewing chamber (412) from the heating device (3) through the flow guiding device, mixing liquid with coffee powders in the brewing chamber (412) to form coffee liquid.

18. The working method for the coffee machine according to claim 17, wherein the method further comprises a step d between step a and step b: covering the main body opening with the first lid body (6) such that first flow guiding channel (51) is connected to the second flow guiding channel (52); and wherein step c comprises: causing heated liquid to flow from the heating device (3) into the first flow guiding channel (51) and the second flow guiding channel (52) successively and to enter into the brewing chamber from the second flow guiding channel (52).

19. The working method for the coffee machine according to claim 18, wherein the water inlet (524) is detachably connected to the second end (512) of the first flow guiding channel (51) inside the main body (1), and the coffee machine further comprises a blocking device provided at a position corresponding to the second end (512) of the first flow guiding channel (51), such that the blocking device is capable of being deformed to prevent liquid from being ejected out of the main body opening when the second flow guiding channel (52) is detached from the first flow guiding channel (51); and wherein step c further comprises: blocking liquid from being ejected out of the main body opening by the blocking device when the second flow guiding channel (52) is detached from the first flow guiding channel (51) during the supplying process of water from the heating device (3) into the flow guiding device.

20. The working method for the coffee machine according to claim 19, wherein a backflow channel (21) is provided inside the main body (1), the backflow channel (21) being communicated to an upper portion of the water tank (2) and the first flow guiding channel (51) respectively, such that at least a part of liquid blocked by the blocking device enters into the backflow channel (21) and flows into the water tank (2); and wherein step c further comprises: causing at least a part of liquid blocked by the blocking device to enter into the backflow channel (21) and to flow into the water tank (2).

21. The working method for the coffee machine according to claim 18, wherein the water inlet (524) is detachably connected to the second end (512) of the first flow guiding channel (51) inside the main body (1), the second end (512) of the first flow guiding channel (51) having a closed top is disposed over the first pipe portion (521) of the second flow guiding channel (52), a side wall of the second end (512) of the first flow guiding channel (51) being provided with a side wall outlet (514), a gap being provided between the side wall outlet (514) and the first pipe portion (521), such that liquid flows from the side wall outlet (514) into the second flow guiding channel (52); and wherein step c further comprises: causing liquid to flow from the side wall outlet (514) into the main body (1) when the second flow guiding channel (52) is detached from the first flow guiding channel (51) during the supplying process of water from the heating device (3) into the flow guiding device.

22. The working method for the coffee machine according to claim 21, wherein a backflow channel (21) is provided inside the main body (1), the backflow channel (21) being communicated to an upper portion of the water tank (2) and the first flow guiding channel (51) respectively, such that at least a part of liquid which flowed from the side wall outlet (514) enters into the backflow channel (21) and flows into the water tank (2); and wherein step c further comprises: causing at least a part of liquid which flowed from the side wall outlet (514) to enter into the backflow channel (21) and to flows into the water tank (2) when the second flow guiding channel (52) is detached from the first flow guiding channel (51) during the supplying process of water from the heating device (3) into the flow guiding device.

23. A working method for the coffee machine according to claim 1, wherein, the coffee machine further comprises a grinding and filtering device which comprises a chamber (41) for containing liquid and coffee particles, a grinding assembly for grinding coffee particles, a driving mechanism (43) connected to the grinding assembly and for driving the grinding assembly, a first filter (44) for filtering coffee liquid in the chamber (41); wherein the chamber (41) is provided with a chamber opening, and at least a part of the grinding assembly is placed in the chamber (41), the chamber (41) comprises the brewing chamber (412) provided with the brewing chamber opening (416), and a liquid channel (411) communicated with the brewing chamber (412) is located on a bottom of the brewing chamber (412), the first filter (44) being partially or totally located on the bottom of the brewing chamber (412), the liquid channel (411) being located on a lower side of the first filter (44) such that coffee liquid in the brewing chamber (412) flows through the first filter (44) before entering the liquid channel (411); and wherein the working method comprises the following steps: a. adding liquid into the water tank (2), and adding coffee particles into the grinding and filtering device; b. grinding coffee particles by the grinding and filtering device; c. transferring liquid into the heating device (3) from the water tank (2), heating liquid by the heating device (3); d. transferring heated liquid into the grinding and filtering device from the heating device (3) through the flow guiding device, mixing liquid with grinded coffee particles in the grinding and filtering device to form coffee liquid; e. filtering coffee liquid by the grinding and filtering device; f. discharging filtered coffee liquid from the grinding and filtering device.

24. The working method for the coffee machine according to claim 23, wherein it further comprises a step g between step a and step b: covering the main body opening with the first lid body (6) such that first flow guiding channel (51) is connected to the second flow guiding channel (52); and wherein step d comprises: causing heated liquid to flow from the heating device (3) into the first flow guiding channel (51) and the second flow guiding channel (52) successively and to enter into the brewing chamber from the second flow guiding channel (52).

25. The working method for the coffee machine according to claim 24, wherein the water inlet (524) is detachably connected to the second end (512) of the first flow guiding channel (51) inside the main body (1), and the coffee machine further comprises a blocking device provided at a position corresponding to the second end (512) of the first flow guiding channel (51), such that the blocking device is capable of being deformed to prevent liquid from being ejected out of the main body opening when the second flow guiding channel (52) is detached from the first flow guiding channel (51); and wherein step d further comprises: blocking liquid from being ejected out of the main body opening by the blocking device when the second flow guiding channel (52) is detached from the first flow guiding channel (51) during the supplying process of water from the heating device (3) into the flow guiding device.

26. The working method for the coffee machine according to claim 25, wherein a backflow channel (21) is provided inside the main body (1), the backflow channel (21) being communicated to an upper portion of the water tank (2) and the first flow guiding channel (51) respectively, such that at least a part of liquid blocked by the blocking device enters into the backflow channel (21) and flows into the water tank (2) when the second flow guiding channel (52) is detached from the first flow guiding channel (51); and wherein step d further comprises: causing at least a part of liquid blocked by the blocking device to enter into the backflow channel (21) and to flow into the water tank (2).

27. The working method for the coffee machine according to claim 23, wherein the water inlet (524) is detachably connected to the second end (512) of the first flow guiding channel (51) inside the main body (1), the second end (512) of the first flow guiding channel (51) having a closed top is disposed over the first pipe portion (521) of the second flow guiding channel (52), a side wall of the second end (512) of the first flow guiding channel (51) being provided with a side wall outlet (514), a gap being provided between the side wall outlet (514) and the first pipe portion (521), such that liquid flows from the side wall outlet (514) into the second flow guiding channel (52); and wherein step d further comprises: causing liquid to flow from the side wall outlet (514) into the main body (1) when the second flow guiding channel (52) is detached from the first flow guiding channel (51) during the supplying process of water from the heating device (3) into the flow guiding device.

28. The working method for the coffee machine according to claim 27, wherein a backflow channel (21) is provided inside the main body (1), the backflow channel (21) being communicated to an upper portion of the water tank (2) and the first flow guiding channel (51) respectively, such that at least a part of liquid which flowed from the side wall outlet (514) enters into the backflow channel (21) and flows into the water tank (2) when the second flow guiding channel (52) is detached from the first flow guiding channel (51); and wherein step d further comprises: causing at least a part of liquid flowed from the side wall outlet (514) to enter into the backflow channel (21) and to flow into the water tank (2), when the second flow guiding channel (52) is detached from the first flow guiding channel (51) during the supplying process of water from the heating device (3) into the flow guiding device.

29. The coffee machine according to claim 5, wherein the first lid body (6) is detachably engaged with the main body (1), and the first lid body (6) comprises a first upper lid body (61) and a first lower lid body (62), the first upper lid body (61) being engaged with the first lower lid body (62) so as to form the cavity (523).

30. The coffee machine according to claim 5, wherein a cavity channel (526) is provided inside the cavity (523), the water inlet (524) and the water outlet (525) being fluidly communicated to the cavity channel (526) respectively so as to form the second flow guiding channel (52).

31. The coffee machine according to claim 6, wherein the first lid body (6) is detachably engaged with the main body (1), and the first lid body (6) comprises a first upper lid body (61) and a first lower lid body (62), the first upper lid body (61) being engaged with the first lower lid body (62) so as to form the cavity (523).

32. The coffee machine according to claim 6, wherein a cavity channel (526) is provided inside the cavity (523), the water inlet (524) and the water outlet (525) being fluidly communicated to the cavity channel (526) respectively so as to form the second flow guiding channel (52).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0060] FIG. 1 is a schematic cross-sectional view of a coffee machine according to embodiment 1 of the present invention.

[0061] FIG. 2 is a schematic cross-sectional view of the coffee machine according to embodiment 1 of the present invention, which shows that a first lid body of the coffee machine is detached from a main body of the coffee machine.

[0062] FIG. 3 is a schematic exploded view of a part of the coffee machine according to embodiment 1 of the present invention.

[0063] FIG. 4 is another schematic exploded view of a part of the coffee machine according to embodiment 1 of the present invention.

[0064] FIG. 5 is a schematic structural view of part A shown in FIG. 2.

[0065] FIG. 6 is a schematic exploded view of the coffee machine according to embodiment 1 of the present invention.

[0066] FIG. 7 is a perspective view of the coffee machine according to embodiment 1 of the present invention, which shows that a first lid body of the coffee machine is completely detached from the main body of the coffee machine.

[0067] FIG. 8 is a schematic view of the coffee machine according to embodiment 1 of the present invention, which shows that a first lower lid body of the coffee machine is covering on the main body of the coffee machine.

[0068] FIG. 9 is another schematic cross-sectional view of the coffee machine according to embodiment 1 of the present invention.

[0069] FIG. 10 is a schematic cross-sectional view of a part of the coffee machine according to embodiment 3 of the present invention.

[0070] FIG. 11 is a schematic cross-sectional view of a part of the coffee machine according to embodiment 3 of the present invention.

[0071] FIG. 12 is a schematic cross-sectional view of an elastic single piece in embodiment 3 of the present invention.

[0072] FIG. 13 is a schematic cross-sectional view of an elastic single piece in embodiment 4 of the present invention.

[0073] FIG. 14 is a schematic cross-sectional view showing that a first pipe portion is connected to a second end of a first flow guiding channel in embodiment 5 of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0074] The present invention is further described with reference to the accompanying drawings.

Embodiment 1

[0075] As shown in FIG. 1, a coffee machine comprises a main body 1, a grinding and filtering device, a water tank 2 and a heating device 3. The grinding and filtering device, the water tank 2 and the heating device 3 is provided inside the main body 1. A main body opening is provided at a top of the main body 1. The coffee machine further comprises a first lid body 6 for covering the main body opening. The grinding and filtering device comprises a chamber 41 for containing liquid and coffee particles, a grinding assembly for grinding coffee particles, a motor 43 connected to the grinding assembly and for driving the grinding assembly, and a first filter 44 for filtering coffee liquid in the chamber 41. As shown in FIGS. 1 and 4, in the present embodiment, the chamber 41 is placed into the main body 1 through the main body opening and is engaged with the main body 1. The chamber 41 comprises a brewing chamber 412 and a collecting chamber 413. A liquid channel 411 communicated with the brewing chamber 412 and the collecting chamber 413 is located on a lower side of the brewing chamber 412. The brewing chamber 412 has a brewing chamber opening 416 at a top of the brewing chamber 412. Coffee beans that need to be ground can be put into the brewing chamber 412 for grinding through the brewing chamber opening 416. The grinding assembly comprises a blade 421 and a blade shaft 422. The brewing chamber 412 is provided with a mounting hole for mounting the blade shaft 422. One end of the blade shaft 422 is mounted on an inner bottom of the brewing chamber 412 and is fixedly connected to the blade 421. Another end of the blade shaft 422 extends out of the brewing chamber 412 through the mounting hole and is connected to the motor 43 by means of a coupling joint assembly. As shown in FIGS. 1 to 3, the blade shaft 422 in the mounting hole is provided with a shaft sleeve 423, and a seal is formed between the shaft sleeve 423 and the mounting hole by a sealing ring 424. The coupling joint assembly is provided at a position corresponding to the grinding assembly, at a lower side of the brewing chamber 412. The coupling joint assembly is consisting of an upper coupling joint 431 and a lower coupling joint 432. The blade shaft 422 is connected to the upper coupling joint 431, and the upper coupling joint 431 is disposed over a motor shaft of the motor 43. The lower coupling joint 432 is engaged with the upper coupling joint 431. When the motor 43 is actuated, the blade shaft 422 and the blade 421 is driven to be rotated by the motor, and coffee beans in the brewing chamber are ground to be coffee powder in the end by the blade 421. When the coffee is brewed in the brewing chamber 412, the heating device 3 may provide hot water for the brewing chamber 412, and coffee powder and hot water are mixed to form coffee liquid. The specific brewing process will be described in detail below.

[0076] Referring to FIGS. 1 and 4, in the present embodiment, the first filter 44 is an annular first filter mesh 44 which is adapted to the shape of the bottom of the brewing chamber 412. The blade shaft 422 is surrounded by the first filter 44 and the first filter 44 is laid on the inner bottom surface of the brewing chamber 412, and at the lower side of the blade 421. The outer peripheral edge of the first filter 44 is provided with a handle 441 such that the first filter 44 can be taken out before cleaning the first filter 44. As described above, the bottom of the brewing chamber 412 is provided with a liquid channel 411 communicated with the brewing chamber 412, such that coffee liquid in the brewing chamber 412 flows towards the liquid channel 411 due to gravity. Coffee liquid inside the brewing chamber 412 can be easily filtered by the first filter 44 located on the inner bottom surface of the brewing chamber 412 and flows into liquid channel 411.

[0077] In the present embodiment, referring to FIGS. 1 to 4 and FIG. 9, as described above, the chamber 41 comprises a brewing chamber 412 and a collecting chamber 413. The collecting chamber 413 is communicated with the brewing chamber 412 via the liquid channel 411 such that filtered coffee liquid flows into the collecting chamber 413 through the liquid channel 411. A bottom of the collecting chamber is provided with a collecting chamber valve 414 for controlling the discharge of coffee liquid from the collecting chamber 413. In order to further filter coffee liquid, a second filter 415 is provided inside the collecting chamber 413, and the second filter 415 is erectly arranged to form a wall surrounding the collecting chamber valve 414 inside the collecting chamber 413. A lower portion of the wall has a plurality of filter holes. The second filter 415 is hold and fixed by the bottom of the first lid body 6 and the bottom surface of the collecting chamber 413. Of course, in other embodiments, the chamber 41 may not comprises the collecting chamber 413, and coffee liquid in the brewing chamber 412 is directly discharged through the first filter 44 from the liquid channel 411. A liquid channel valve may be provided on the liquid channel 411 as required to control the discharge of the liquid. Alternatively, the second filter may be provided in the liquid channel 411 to re-filter coffee liquid.

[0078] Referring to FIGS. 1, 2, 6 and 8, the coffee machine further comprises a flow guiding device. The flow guiding device comprises a first flow guiding channel 51 and a second flow guiding channel 52 detachably connected to the first flow guiding channel 51. The first end 511 of the first flow guiding channel 51 is connected to the heating device 3. The second flow guiding channel 52 has a water inlet 524 and a water outlet 525. The water outlet 525 is located at a position corresponding to a brewing chamber opening 416 such that liquid is supplied to the brewing chamber 412. The first lid body 6 is detachably engaged with the main body 1. The first lid body 6 comprises a first upper lid body 61 and a first lower lid body 62. The first upper lid body 61 is engaged with the first lower lid body 62 so as to form a cavity 523. The first lower lid body 62 extends downwardly to form a first pipe portion 521 and a second pipe portion 522 of the second flow guiding channel 52, and the first pipe portion 521 and the second pipe portion 522 is communicated with the cavity 523, respectively. The cavity 523 is provided with a cavity channel 526 having a cavity channel lid 527 and an open top. The open top is covered by the cavity channel lid 527 to define the flowing direction of hot water passing through the cavity channel 526. The water inlet 524 and the water outlet 525 are fluidly communicated to the cavity channel 526 respectively so as to form the second flow guiding channel 52. The water inlet 524 and the water outlet 525 of the second flow guiding channel 52 are located at lower ends of the first pipe portion 521 and the second pipe portion 522 respectively. When the first lid body 6 is covered at the top of the main body 1, the first pipe portion 521 is inserted into the second end 512 of the first flow guiding channel 51 to communicate with the first flow guiding channel 51. One end of the heating device 3 is communicated with the water tank 2, and the heating device 3 is located on the a lower side of the water tank 2, such that water flows from the water tank into the heating device 3 and is heated to be hot water. A check valve 31 is provided at the junction of the heating device 3 with the water tank 2 to prevent a back flow of hot water from the heating device 3 into the water tank. The first end 511 of the first flow guiding channel 51 is communicated with another end of the heating device 3. Water which flowed into heating device 3 forms a pressure, when water is heated, to push a flow of hot water into the first end 511 of the first flow guiding channel 51. Hot water enters into the second flow guiding channel 52 along the first flow guiding channel 51, i.e., hot water enters into the first pipe portion 521, the cavity channel 526 and the second pipe portion 522 successively, and finally enters into the brewing chamber 412 and is mixed with the coffee powder to form coffee liquid. In the present embodiment, in order to accelerate dissolution of coffee powder into hot water, a nozzle (which is not shown) is provided at the water outlet 525 of the second pipe portion 522 such that liquid is ejected into the brewing chamber 412 via nozzle. Since the first pipe portion 521 is communicated with the cavity 523 of the first lid body 6, the lower end of the first pipe portion 521 is pulled out from the first flow guiding channel 51 when the first lid body 6 is removed from the main body 1. This operation may cause danger when hot water is transferred into the brewing chamber 412 by the flow guiding device, since the hot water transferred by the first flow guiding channel 51 would be directly ejected out of the main body 1 due to water pressure and thereby causing scald of a user.

[0079] In order to prevent the above-mentioned safety hazards, as shown in FIGS. 1, 2 and 5, in the present embodiment, the coffee machine further comprises a blocking device provided for preventing hot water from being ejected out of the main body. The blocking device is an elastic assembly which comprises a baffle 71 and a torsion spring 712. In order that at least a part of liquid blocked by the blocking device flows back into the water tank 2, a backflow channel 21 is provided inside the main body 1. The backflow channel 21 is communicated to an upper portion of the water tank 2 and the first flow guiding channel 51 respectively. The backflow channel 21 is perpendicular to the first flow guiding channel 51. One end of the backflow channel 21 is connected to the upper portion of the tank 2 and another end of the backflow channel 21 is the closed end. An upper side wall of the backflow channel 21 is provided with an upper opening 211 which is communicated with the main body opening, and a lower side wall of the backflow channel 21 is provided with a lower opening 212 which is communicated with the second end 512 of the first flow guiding channel 51. The torsion spring 712 is fixed in the backflow channel 21. A first end of the baffle 71 is connected to the torsion spring 712 and a second end of the baffle 71 is a free end which is movable around the first end. The upper opening 211 is downwardly provided with a flange 213 which is slightly higher than the first end of the baffle 71. When the first lid body 6 is not placed on the main body, the baffle 71 is abutted against the flange 213 under the action of an elastic force and is located at a first position such that the upper opening 211 is closed. When the first pipe portion 521 of the second flow guiding channel 52 is inserted into the upper opening 211 to communicate with the first flow guiding channel 51, the second end of the baffle 71 is pushed to be moved from a first position (horizontal position) around the first end of the baffle 71 to a second position (vertical position) by the first pipe portion 521, such that the first pipe portion 521 is communicated with the second end 512 of the first flow guiding channel 51. When the first pipe portion 521 is detached from the second end 512 of the first flow guiding channel 51, an elastic force is provided by the torsion spring 712 such that the second end of the baffle 71 is moved from the second position (vertical position) around the first end of the baffle to the first position (horizontal position), and thus the upper opening 211 is closed. Thus, liquid ejected out of the second end 512 of the first flow guiding channel 51 is blocked by the baffle 71 and flows back into the water tank 2 through the backflow channel 21.

[0080] As shown in FIGS. 6 and 7, a second lid body 63 for covering the brewing chamber opening 416 is provided on a lower side of the first lid body 6. An elastic member 633 is provided between the first lid body 6 and the second lid body 63, such that a relative seal is formed between the second lid body 63 and the brewing chamber 412 when the first lid body 6 is fixed onto the main body 1. A middle portion of the second lid body 63 is provided with a second lid body through hole 631 which is located at a position corresponding to the second pipe portion 522. The second lid body 63 is disposed over the second pipe portion 522 via the second lid body through hole 631. In the present embodiment, the elastic member 633 is a spring 633 which is disposed over the second pipe portion 522 and is located between the second lid body 63 and the bottom of the first lid body 6. A surrounding wall 101 extending out of the main body opening is protruded upwardly from the main body opening. A side portion of the first lid body 6 is provided with a locking button 611 and a buckle 621. The surrounding wall 101 is provided with a buckling part 622 corresponding to a buckle 621. The locking button 611 is used for driving the buckle 621 to be engaged with the buckling part 622. When in use, the first lid body 6 is placed on the main body opening; and the buckle 621 is pressed into the first lid body 6 by pressing the locking button 611, the first lid body 6 is pressed into the main body 1 such that a bottom of the first lid body 6 is inserted into a space surrounded by the surrounding wall 101; an outer wall of the first lower lid body 62 is in contact with a inner wall of the surrounding wall 101; the buckle 621 is inserted into the buckling part 622 and is firmly engaged with the buckling part 622, and the first lid body 6 is thus fixed onto the main body 1. In addition, when the first lid body 6 is pressed, the second lid body 63 is pushed to be abutted against the brewing chamber opening 416 by the first lid body 6 via the spring 633. The first lid body 6 is locked on the main body 1 such that the spring 633 is compressed between the second lid body 63 and the first lid body 6, and an elastic force is provided by the compressed spring 633 such that the second lid body 63 is firmly engaged with the opening of the brewing chamber 412. A relative seal is formed between the second lid body 63 and the opening of the brewing chamber 412 to prevent coffee powder escaping with a steam in the brewing chamber 412 from a gap between the second lid body 63 and the opening of the brewing chamber 412.

[0081] Referring to FIGS. 1-2 and 7-8, the second lid body 63 is provided with a plurality of second exhaust holes 632 for discharging excess steam in the brewing chamber 412 to prevent a high pressure in the brewing chamber 412. In the present embodiment, the second exhaust holes 632 have a diameter of about 0.5 mm and the second exhaust holes 632 are finely distributed on the second lid body 63 such that a part of the second lid body 63 forms a mesh structure to prevent the coffee powder being discharged with a steam from the second exhaust holes 632. The first lid body 6 is provided with a plurality of first exhaust holes 601. The first exhaust hole 601 is communicated with the second exhaust hole 632, and a part of steam in the brewing chamber 412 is discharged by the second exhaust holes 632, and thus the steam is discharged out of the main body through the first exhaust holes 601.

[0082] A working method for the coffee machine of the present embodiment comprises the following steps: a. adding liquid into the water tank 2, and adding coffee particles into the grinding and filtering device; b. grinding coffee particles by the grinding and filtering device; c. transferring liquid into the heating device 3 from the water tank 2, heating liquid by the heating device 3; d. transferring heated liquid into the grinding and filtering device from the heating device 3 through the flow guiding device, mixing liquid with grinded coffee particles in the grinding and filtering device to form coffee liquid; e. filtering coffee liquid by the grinding and filtering device; f. discharging filtered coffee liquid from the grinding and filtering device.

[0083] In the present embodiment, the working method further comprises a step g between step a and step b: covering the main body opening with the first lid body 6 such that first flow guiding channel 51 is connected to the second flow guiding channel 52; and wherein step d comprises: causing heated liquid to flow from the heating device 3 into the first flow guiding channel 51 and the second flow guiding channel 52 successively and to enter into the brewing chamber from the second flow guiding channel 52.

[0084] In the present embodiment, step d further comprises: blocking liquid from being ejected out of the main body opening by the blocking device when the second flow guiding channel 52 is detached from the first flow guiding channel 51 during the supplying process of water from the heating device 3 into the flow guiding device.

[0085] In the present embodiment, step d further comprises: causing at least a part of liquid blocked by the blocking device to enter into the backflow channel 21 and to flow into the water tank 2.

Embodiment 2

[0086] The present embodiment is substantially the same as that of Embodiment 1 except that the structure of the flow guiding device is different. The flow guiding device of the coffee machine in the present embodiment is similar to that shown in FIG. 2. However, the flow guiding device of the coffee machine in the present embodiment does not have a second flow guiding channel 52. The flow guiding device of the coffee machine in the present embodiment comprises a first flow guiding channel 51, and the first end 511 of the first flow guiding channel 51 is connected to the heating device 3. The brewing chamber 412 is provided with a brewing chamber through hole corresponding to a second end 512 of the first flow guiding channel 51. The second end 512 of the first flow guiding channel 51 is inserted into the brewing chamber 412 through the brewing chamber through hole.

Embodiment 3

[0087] The present embodiment is substantially the same as that of Embodiment 1 except that the structure of the blocking device is different. The whole structure of the coffee machine in the present embodiment is similar to that shown in FIG. 1 and FIG. 2. As shown in FIG. 10 and FIG. 12, the blocking device is a sheet-like elastic single piece 72 fixed onto the upper opening 211. The elastic single piece 72 has a circular cross section, which corresponds to the shape of the corresponding upper opening 211. A middle portion of the elastic single piece 72 is provided with a cutout 721. The periphery of the elastic single piece 72 is provided with a convex wall 722 which tightly surrounds a flange 213 and is fixed to an outer side wall of the flange 213. When the first pipe portion 521 of the second flow guiding channel 52 is inserted into the upper opening 211, the cutout 721 of the elastic single piece 72 is opened by the first pipe portion 521 and thus the first pipe portion 521 of the second flow guiding channel 52 can be inserted into the first flow guiding channel 51 through the cutout 721 of the elastic single piece 72. When the first pipe portion 521 is detached from the second end 512 of the first flow guiding channel 51, the first pipe portion 521 is pulled out from the cutout such that the opened cutout 721 is closed. Liquid ejected out of the second end 512 of the first flow guiding channel 51 is thus blocked by the elastic single piece 72 with the closed cutout 721 and flows back into the water tank 2 through the backflow channel 21.

Embodiment 4

[0088] The present embodiment is substantially the same as that of Embodiment 3 except that the number and the relative position of the cut 721 of the elastic single piece 72 are different. The whole structure of the coffee machine in the present embodiment is similar to that shown in FIG. 1 and FIG. 2. As shown in FIG. 13, in the present embodiment, the middle portion of the elastic single piece 72 is provided with at least two cutouts 721 which cross each other. The connection of elastic single piece 72 with the upper opening 211 in the backflow channel 21 is same as that in Embodiment 3, which will not be described again.

Embodiment 5

[0089] The present embodiment is substantially the same as that of Embodiment 1 except that the structure of the first pipe portion 521 and the second end 512 of the first flow guiding channel 51 and the connection of the first pipe portion 521 with the second end 512 of the first flow guiding channel 51 are different. FIG. 14 is a schematic cross-sectional view which only shows that the first pipe portion 521 is connected to the second end 512 of the first flow guiding channel 51. The whole structure of the coffee machine in the present embodiment is similar to that shown in FIG. 1 and FIG. 2. As shown in FIGS. 1, 2 and 13, a lower end of the first pipe portion 521 has the water inlet 524 of the second flow guiding channel 52. The diameter of the water inlet 524 is smaller than the diameter of the first pipe portion 521. The second end 512 of the first flow guiding channel 51 is inserted into the first pipe portion 521 of the second flow guiding channel 52 through the water inlet 524. The gap is provided between the side wall outlet 514 and the first pipe portion 521, such that hot water flows from the side wall outlet 514 into the second flow guiding channel 52.