阅读说明：本技术 一种反向冲洗快速疏通全自动咖啡机滤网堵塞的冲煮头 (Back flushing and quick dredging brewing head for blocking filter screen of full-automatic coffee machine ) 是由 不公告发明人 于 2019-10-14 设计创作，主要内容包括：本发明公开了一种反向冲洗快速疏通全自动咖啡机滤网堵塞的冲煮头,冲洗腔和咖啡冲泡腔相互平行地设于冲煮头基座上,且均位于冲煮头滤网的上方,堵头弹性支撑在冲洗腔内并形成第一单向阀芯,第一单向阀芯的自由端抵触在冲洗腔的内腔壁上并将冲洗腔封闭；所述密封体弹性支撑在咖啡冲泡腔内并形成第二单向阀芯,第二单向阀芯的自由端抵触在咖啡冲泡腔的内腔壁上并将咖啡冲泡腔封闭。冲泡咖啡过程中咖啡溶液是对冲煮头滤网的正方向冲洗,经过正方向的冲洗已经部分有所松动。冲洗液冲向冲煮头滤网实现冲煮头滤网的反向冲洗,进行反方向清洗,可以收到比较理想的滤网清洗效果,不需要再进行手动拆卸进行人工的操作,减轻了劳动强度,大幅提升效率。(The invention discloses a brewing head for quickly dredging the blockage of a filter screen of a full-automatic coffee machine by back flushing, wherein a flushing cavity and a coffee brewing cavity are arranged on a brewing head base in parallel and are both positioned above the filter screen of the brewing head; the sealing body is elastically supported in the coffee brewing cavity and forms a second one-way valve core, and the free end of the second one-way valve core is abutted against the inner cavity wall of the coffee brewing cavity and seals the coffee brewing cavity. In the process of brewing coffee, the coffee solution washes the filter screen of the brewing head in the positive direction, and part of the coffee solution is loosened after washing in the positive direction. The washing liquid washes to the first filter screen of boiling and realizes the backwash of first filter screen of boiling, washs in the opposite direction, can receive the filter screen cleaning performance of comparison ideal, need not carry out manual dismantlement again and carries out artificial operation, has alleviateed intensity of labour, promotes efficiency by a wide margin.)

1. The utility model provides a backwash head of quick mediation full-automatic coffee machine filter screen jam, includes first body (1) of boiling, first base (2) of boiling and first filter screen (3) of boiling, and on first base (2) of boiling was fixed in first body (1) of boiling, first filter screen (3) of boiling were fixed in on first base (2) of boiling, its characterized in that: the washing device is characterized by further comprising a washing cavity (410), a coffee brewing cavity (510), a plug (42) and a sealing body (53), wherein the washing cavity (410) and the coffee brewing cavity (510) are arranged on the brewing head base (2) in parallel and are both located above the brewing head filter screen (3), the plug (42) is elastically supported in the washing cavity (410) and forms a first one-way valve core, and the free end of the first one-way valve core is abutted against the inner cavity wall of the washing cavity (410) and seals the washing cavity (410); a top port of the flushing cavity (410) is connected with flushing liquid, the flushing liquid jacks up a first one-way valve core in the flushing cavity (410) and opens the flushing cavity (410), and the flushing liquid flushes to the flushing head filter screen (3) from a bottom port of the flushing cavity (410) and cleans the flushing head filter screen (3); the sealing body (53) is elastically supported in the coffee brewing cavity (510) and forms a second one-way valve core, and the free end of the second one-way valve core is abutted against the inner cavity wall of the coffee brewing cavity (510) and seals the coffee brewing cavity (510); the coffee solution mixed with the coffee powder is poured into the bottom port of the coffee brewing cavity (510) from the lower part of the brewing head filter screen (3), the coffee solution pushes open the second one-way valve core in the coffee brewing cavity (510) and opens the coffee brewing cavity (510), and the coffee solution is discharged from the top port of the coffee brewing cavity (510).

2. The back-flushing quick-break full-automatic coffee machine strainer clogged brewing head of claim 1, wherein: the washing head comprises a washing head base (2), wherein a back washing channel (41) is connected to the washing head base (2) in a sealing mode, a washing cavity (410) comprises an upper washing hole penetrating through the back washing channel (41) and a washing interface (21) penetrating through the washing head base (2), the washing interface (21) and the upper washing hole are both of a step hole structure, the upper washing hole is arranged along the axis direction of the back washing channel (41), the upper washing hole comprises an upper hole portion (411), a lower hole portion (412) and a middle cylindrical hole (413) which are mutually communicated, the lower hole portion (412) and the upper hole portion (411) are arranged at two ends of the middle cylindrical hole (413), the diameters of the upper hole portion (411) and the lower hole portion (412) are larger than that of the middle cylindrical hole (413), and the lower hole portion (412) is connected with the washing interface (21).

3. The back-flushing quick-break full-automatic coffee machine strainer clogged brewing head of claim 2, wherein: the plug (42) penetrates through the flushing interface (21) and extends into the lower hole portion (412), a plug pressure spring (43) and a plug retainer ring (44) are sleeved on the plug (42), the upper end of the plug pressure spring (43) abuts against the plug retainer ring (44), the lower end of the plug pressure spring (43) abuts against the flushing head base (2), the bottom free end of the plug (42) abuts against the step surface of the flushing interface (21) through the plug pressure spring (43), and the bottom free end of the plug (42) seals the flushing interface (21). .

4. The back-flushing quick-break full-automatic coffee machine strainer clogged brewing head of claim 3, characterized in that: the plug (42) is of a T-shaped structure with a pin shaft portion (421) and a base portion (422), the pin shaft portion (421) penetrates through the flushing port (21) and extends into the lower hole portion (412), the plug pressure spring (43) and the plug retainer ring (44) are both sleeved on the pin shaft portion (421), a positioning table (423) is arranged at the tail end of the pin shaft portion (421), the plug retainer ring (44) is axially positioned on the pin shaft portion (421) through the positioning table (423), and the base portion (422) is abutted to a step surface of the flushing port (21).

5. The back-flushing quick-break full-automatic coffee machine strainer clogged brewing head of claim 2, wherein: an inlet joint (6) is connected in the upper hole portion (411) in a sealing mode, and the inlet joint (6) comprises an outer sleeve body (61) and an inner sleeve body (62) which are coaxial and fixed to each other.

6. The back-flushing quick-break full-automatic coffee machine strainer clogged brewing head of claim 5, wherein: a joint pressing plate (7) is arranged in the brewing head body (1), an inner tube body (62) on the inlet joint (6) penetrates through the joint pressing plate (7), and a step surface between the upper hole portion (411) and the middle cylindrical hole (413) enables an outer sleeve body (61) to abut against the joint pressing plate (7).

7. The back-flushing quick-break full-automatic coffee machine strainer clogged brewing head of claim 1, wherein: the brewing head base (2) is provided with a coffee outlet channel (22), and the coffee brewing cavity (510) is arranged in the axis direction of the coffee outlet channel (22).

8. The back-flushing quick-break full-automatic coffee machine strainer clogged brewing head of claim 7, wherein: the coffee brewing cavity (510) is of a stepped hole structure, a coffee pressure accumulating spring (51) and a coffee outlet plug (52) are arranged in the coffee brewing cavity (510), the coffee outlet plug (52) is hermetically fixed at the lower port of the coffee brewing cavity (510), a coffee flow channel (520) is arranged in the axis direction of the coffee outlet plug (52), the coffee flow channel (520) is communicated with the coffee brewing cavity (510), the upper end of the coffee pressure accumulating spring (51) abuts against the stepped surface of the coffee brewing cavity (510), and the lower end abuts against the free end of the bottom of the sealing body (53) against the coffee outlet plug (52) and seals the coffee flow channel (520).

9. The back-flushing quick-break full-automatic coffee machine strainer clogged brewing head of claim 8, wherein: the sealing body (53) is of a sealing ball structure.

10. The back-flushing quick-break full-automatic coffee machine strainer clogged brewing head of claim 1, wherein: be equipped with on the bottom surface of boiling head base (2) concave part (20), boiling head filter screen (3) are convex structure, are equipped with the fixed orifices in the circular department of boiling head filter screen (3), and boiling head filter screen (3) are fixed in on boiling head base (2) through the screw connection, and form a cavity between the interior cambered surface of boiling head filter screen (3) and concave part (20).

The technical field is as follows:

the invention relates to the technical field of beverage machines, in particular to a brewing head of a coffee machine.

Background art:

the full-automatic coffee machine has several core components: the bean grinding set, the brewing device component, the heating component, the water path system, the slag discharging component and the like. Therefore, the coffee powder thickness ratio, the extraction pressure, the extraction temperature and the extraction flow rate are controlled to brew a cup of coffee. Because the powder has a certain thickness proportion, a small amount of fine powder flows through the brewing head of the brewing device under the action of extraction pressure and enters the coffee, the brewing head is small holes which are distributed according to a certain proportion, most of the coffee powder is still blocked at the powder cake end by the brewing head, so a certain phenomenon exists, and a small amount of fine powder can be just blocked in the small holes of the brewing head along with the lapse of time.

Full-automatic coffee machines have strict regulations, and the brewer must be cleaned with special tablets at intervals of a certain number of cups, because the main component of the tablet is citric acid, which has a certain dissolving effect on coffee stains but is basically ineffective on coffee fine particles. The fine particles still form a plug. The number of the blocked holes around the slowly blocked small holes is gradually increased to form local area blockage, which seriously influences the quality of coffee extraction and finally causes the failure of the coffee machine.

The filter screen hole of the brewing head is blocked with certain necessity due to the existence of the coffee fine powder, when the blockage is formed, the coffee or cleaning flow direction is unidirectional, namely the coffee or cleaning flow direction is towards the coffee outlet, the liquid washing effect is lacked, like washing clothes, the clothes can be washed clean only by washing the clothes continuously left and right, the coffee flows in the unidirectional direction, and sometimes the pressure is larger, and the through hole is difficult to be dredged.

The main approaches to the treatment of blockages that have occurred are divided into the following two:

1) the brewing device is disassembled, the filter screen of the brewing head is soaked by the tablet and then is dredged by a brush, time and labor are wasted, and the operation is troublesome and complicated;

2) the surface of the brewing device is brushed back and forth by a fine hair brush without disassembling the brewing device, so that holes which are partially blocked and have particles protruding on the surface can be brushed off, and therefore dredging is carried out, but part of blocked holes which do not protrude are not dredged, and meanwhile, the operation space and the angle are inconvenient.

Therefore, there is a need to improve the prior art to overcome the deficiencies of the prior art.

The invention content is as follows:

the invention provides a brewing head for quickly dredging blocked filter screens of a full-automatic coffee machine by back flushing, which is used for dredging the filter screens of the brewing head by adopting a mode of back flushing by flushing fluid, namely, the back flushing force is introduced, and under the condition of washing and swinging of the flushing force in the positive and negative directions, blocked particles can be loosened more easily and are cleaned and dredged.

The technical scheme adopted by the invention is as follows:

a reverse-flushing brewing head capable of rapidly dredging filter screen blockage of a full-automatic coffee machine comprises a brewing head body, a brewing head base and a brewing head filter screen, wherein the brewing head base is fixed on the brewing head body, the brewing head filter screen is fixed on the brewing head base, the full-automatic coffee machine further comprises a flushing cavity, a coffee brewing cavity, a plug and a sealing body, the flushing cavity and the coffee brewing cavity are arranged on the brewing head base in parallel and are both positioned above the brewing head filter screen, the plug is elastically supported in the flushing cavity and forms a first one-way valve core, and the free end of the first one-way valve core is abutted against the inner cavity wall of the flushing cavity and seals the flushing cavity; the top port of the flushing cavity is connected with flushing liquid, the flushing liquid jacks a first one-way valve core in the flushing cavity and opens the flushing cavity, and the flushing liquid flushes to the filter screen of the brewing head from the bottom port of the flushing cavity and cleans the filter screen of the brewing head; the sealing body is elastically supported in the coffee brewing cavity and forms a second one-way valve core, and the free end of the second one-way valve core is abutted against the inner cavity wall of the coffee brewing cavity and seals the coffee brewing cavity; the coffee solution mixed with the coffee powder is poured into the bottom port of the coffee brewing cavity from the lower part of the filter screen of the brewing head, the coffee solution pushes open the second one-way valve core in the coffee brewing cavity and opens the coffee brewing cavity, and the coffee solution is discharged from the top port of the coffee brewing cavity.

Furthermore, the base of the flushing head is hermetically connected with a backwashing channel, the flushing cavity comprises an upper flushing hole penetrating through the backwashing channel and a flushing interface penetrating through the base of the flushing head, the flushing interface and the upper flushing hole are of a stepped hole structure, the upper flushing hole is arranged along the axis direction of the backwashing channel and comprises an upper hole part, a lower hole part and a middle cylindrical hole which are mutually communicated, the lower hole part and the upper hole part are arranged at two ends of the middle cylindrical hole, the diameters of the upper hole part and the lower hole part are larger than that of the middle cylindrical hole, and the lower hole part is hermetically connected with the flushing interface.

Furthermore, the plug penetrates through the flushing interface and extends into the lower hole part, a plug pressure spring and a plug retainer ring are sleeved on the plug, the upper end of the plug pressure spring is abutted against the plug retainer ring, the lower end of the plug pressure spring is abutted against the boiling head base, the bottom free end of the plug is abutted against the step surface of the flushing interface through the plug pressure spring, and the bottom free end of the plug is closed to the flushing interface.

Furthermore, the washing plug is of a T-shaped structure with a pin shaft portion and a base portion, the pin shaft portion penetrates through the washing port and extends into the lower hole portion, the pin shaft portion is sleeved with the plug pressure spring and the plug retainer ring, the tail end of the pin shaft portion is provided with a positioning table, the plug retainer ring is axially positioned on the pin shaft portion through the positioning table, and the base portion abuts against a step surface of the washing port.

Further, an inlet joint is hermetically connected in the upper hole part, and the inlet joint comprises an outer sleeve body and an inner pipe body which are coaxial and fixed with each other.

Furthermore, a joint pressure plate is arranged in the brewing head body, an inner pipe body on the inlet joint penetrates through the joint pressure plate, and the outer sleeve body is abutted against the joint pressure plate by a step surface between the upper hole part and the middle cylindrical hole.

Furthermore, a coffee outlet channel is arranged on the brewing head base, and the coffee brewing cavity is arranged in the axis direction of the coffee outlet channel.

Furthermore, the coffee brewing cavity is of a stepped hole structure, a coffee pressure accumulating spring and a coffee outlet plug are arranged in the coffee brewing cavity, the coffee outlet plug is fixed at the lower port of the coffee brewing cavity in a sealing mode, a coffee flow channel is arranged in the axis direction of the coffee outlet plug and communicated with the coffee brewing cavity, the upper end of the coffee pressure accumulating spring abuts against the stepped surface of the coffee brewing cavity, the lower end of the coffee pressure accumulating spring abuts against the bottom free end of the sealing body against the coffee outlet plug, and the coffee flow channel is sealed.

Further, the sealing body is of a sealing ball structure.

Furthermore, the bottom surface of the brewing head base is provided with a groove part, the brewing head filter screen is of an arc-shaped structure, a fixing hole is formed in the circular part of the brewing head filter screen, the brewing head filter screen is fixed on the brewing head base through screw connection, and a cavity is formed between the inner arc surface of the brewing head filter screen and the groove part.

The invention has the following beneficial effects:

1) the mode of regular back flushing is realized very conveniently, can realize a key operation, and the waste water of back flushing directly flows into the waste water box moreover, need not carry out the secondary clearance.

2) The plugging holes are loosened to some extent after being soaked in the tablets, are partially loosened after being washed in the positive direction, and are cleaned in the negative direction, so that an ideal effect can be achieved, manual disassembly for manual operation is not needed, the labor intensity is reduced, and the efficiency is greatly improved.

3) Reduce coffee stain and coffee scale, the coffee is more sanitary: the introduction of a back flush makes the coffee more hygienic, since the coffee flow in this area of the tablet is also slower once the clogging has developed, which makes the area clogged, more prone to coffee stains and scaling, and which may develop mould if it is carried out for a longer time.

Description of the drawings:

FIG. 1 is a cross-sectional structural view of the present invention.

Fig. 2 is an exploded view of the present invention.

Figure 3 is a block diagram of the flush port of the present invention on a brew head base.

Figure 4 is a block diagram of the flush port on the brew head base of the present invention.

Fig. 5 is a structural view of an inlet joint according to the present invention.

Fig. 6 is a structural view of the present invention when brewing coffee.

Fig. 7 is a structural view of the present invention at the time of cleaning.

The specific implementation mode is as follows:

the invention will be further described with reference to the accompanying drawings.

Example 1:

referring to fig. 1 and 2, the brewing head for quickly dredging the filter screen blockage of the full-automatic coffee machine through back washing comprises a brewing head body 1, a brewing head base 2 and a brewing head filter screen 3, wherein the brewing head base 2 is fixed on the brewing head body 1, and the brewing head filter screen 3 is fixed on the brewing head base 2.

A washing cavity 410 and a coffee brewing cavity 510 are arranged on a brewing head base 2, the washing cavity 410 and the coffee brewing cavity 510 are both vertically arranged and are positioned above a brewing head filter screen 3, a plug 42 and a sealing body 53 are respectively and correspondingly arranged in the washing cavity 410 and the coffee brewing cavity 510, the plug 42 is elastically supported in the washing cavity 410 and forms a first one-way valve core, and the bottom free end of the first one-way valve core is abutted against the inner cavity wall of the washing cavity 410 and seals the washing cavity 410; the sealing body 53 is elastically supported in the coffee brewing chamber 510 and forms a second one-way valve core, and the bottom free end of the second one-way valve core is abutted against the inner cavity wall of the coffee brewing chamber 510 and seals the coffee brewing chamber 510.

The top port of the flushing cavity 410 is connected with flushing liquid, the flushing liquid jacks up a first one-way valve core in the flushing cavity 410 and opens the flushing cavity 410, and the flushing liquid flushes towards the filter screen 3 of the brewing head from the bottom port of the flushing cavity 410 and cleans the filter screen 3 of the brewing head. The coffee solution mixed with the coffee powder is poured into the bottom port of the coffee brewing chamber 510 from the lower part of the brewing head filter screen 3, the coffee solution pushes open the second one-way valve core in the coffee brewing chamber 510 and opens the coffee brewing chamber 510, and the coffee solution is discharged from the top port of the coffee brewing chamber 510.

With reference to fig. 4-6, the structure of the plug 42 forming the first one-way valve in the flush chamber 410 of the present invention will be described in detail as follows:

a back-flushing channel 41 is sealingly fixed to the base 2 of the brewing head, and in the present invention the flushing chamber 410 comprises an upper flushing hole extending through the back-flushing channel 41 and a flushing nipple 21 extending through the base 2 of the brewing head. The upper flushing hole and the flushing port 21 are of stepped bore construction.

The upper washing hole is arranged along the axial direction of the back washing channel 41 and comprises an upper hole part 411, a lower hole part 412 and a middle cylindrical hole 413 which are coaxially arranged and mutually communicated, wherein the lower hole part 412 and the upper hole part 411 are arranged at two ends of the middle cylindrical hole 413, the diameters of the upper hole part 411 and the lower hole part 412 are larger than that of the middle cylindrical hole 413, the lower hole part 412 is hermetically connected with the washing interface 21, and the plug 42 penetrates through the washing interface 21 and is elastically supported in the lower hole part 412.

In order to elastically support the plug 42 in the flushing cavity 410, a plug compression spring 43 and a plug retainer 44 are sleeved on the plug 42, the upper end of the plug compression spring 43 abuts against the plug retainer 44, the lower end of the plug compression spring 43 abuts against the brewing head base 2, the plug 42 is elastically supported in the flushing cavity 410 through the plug compression spring 43, the bottom free end of the plug 42 abuts against the step surface of the flushing connector 21, and the flushing connector 21 is closed by the bottom free end of the plug 42.

In order to facilitate positioning and installation, the choke plug 42 is of a T-shaped structure and comprises a pin shaft portion 421 and a base portion 422, the pin shaft portion 421 penetrates through the flushing port 21 and extends into the lower hole portion 412, the base portion 422 is arranged in the flushing port 21, the choke plug pressure spring 43 and the choke plug retainer ring 44 are both sleeved on the pin shaft portion 421, a positioning table 423 is arranged at the tail end of the pin shaft portion 421, and the choke plug retainer ring 44 is axially positioned on the pin shaft portion 421 through the positioning table 423. The base portion 422 abuts against a step surface of the flush port 21. To ensure good sealing, an O-ring is sleeved on the base 422 of the end of the plug 42, and the O-ring abuts against the step surface of the flush port 21 to form a seal.

A flushing hose 4100 is connected to a liquid inlet at the upper end of the back flushing channel 41, a water pump is connected to the flushing hose 4100 and used for injecting pressurized flushing liquid into the back flushing channel 41 and then pushing the plug 42 open so that the flushing cavity 410 is in a through state.

To facilitate the access of the flush hose 4100 into the flush chamber 410, an inlet fitting 6 is sealingly connected within the upper bore portion 411, and the flush hose 4100 is sealingly connected to the inlet fitting 6.

The inlet joint 6 has the following specific structure: the inlet fitting 6 includes an outer body 61 and an inner body 62, the outer body 61 being secured to the inner body 62. The irrigation hose 4100 is sealingly connected to the inner tube 62.

In order to facilitate positioning and installation of the back flushing channel 41 and the inlet joint 6, a joint pressure plate 7 is arranged in the brewing head body 1, an inner pipe body 62 on the inlet joint 6 penetrates through the joint pressure plate 7, and the outer sleeve body 61 is abutted against the joint pressure plate 7 by the step surface of the upper hole part 411.

The structure of the sealing body 53 forming the second one-way valve inside the coffee brewing chamber 510 in the present invention will be described in detail below:

the brewing head base 2 is provided with a coffee outlet channel 22, the coffee outlet channel 22 is parallel to the washing interface 21, the coffee outlet channel 22 and the brewing head base 2 are integrally formed, and the coffee brewing cavity 510 is arranged in the axial direction of the coffee outlet channel 22.

The coffee brewing cavity 510 is of a stepped hole structure, a coffee pressure accumulating spring 51 and a coffee outlet plug 52 are arranged in the coffee brewing cavity 510, the coffee outlet plug 52 is hermetically fixed at the lower port of the coffee brewing cavity 510, a coffee flow channel 520 is arranged in the axial direction of the coffee outlet plug 52, the coffee flow channel 520 is communicated with the coffee brewing cavity 510, the upper end of the coffee pressure accumulating spring 51 is abutted against the stepped surface of the coffee brewing cavity 510, the lower end of the coffee pressure accumulating spring 53 is abutted against the coffee outlet plug 52, and the coffee flow channel 520 is sealed.

The sealing body 53 has a sealing ball structure, and the sealing body 53 and the coffee pressure accumulating spring 51 are fixed by welding.

On the bottom surface of the brewing head base 2 a recess portion 20 is provided, in which recess portion 20 both the flushing interface 21 and the coffee outlet channel 22 are provided, and both the flushing interface 21 and the coffee outlet channel 22 are provided along the axial direction of the brewing head base 2.

The brewing head filter screen 3 is of an arc-shaped structure, a fixing hole is formed in the circular position of the brewing head filter screen 3, the brewing head filter screen 3 is fixed on the brewing head base 2 through screws, and a cavity is formed between the inner arc surface of the brewing head filter screen 3 and the groove part 20. The brewing head filter screen 3 is of a circular arc structure, so that the brewing head filter screen 3 can be prevented from being directly attached to the washing port 21 and the coffee outlet channel 22, and the brewing head filter screen 3 is further prevented from being blocked.

To ensure a better sealing, sealing rings are provided between the brewing head base 2 and the back-flushing channel 41 and between the coffee outlet plug 52 and the brewing head base 2.

The following describes the cleaning process of the present invention in detail with reference to fig. 6 and 7:

when the full-automatic coffee machine is used for brewing coffee, the brewing chamber 9 used for brewing coffee powder is arranged below the brewing head body 1, the structure and the principle of the brewing chamber used for brewing coffee are the prior art, so that the invention only introduces the solution traveling path of the brewing process of the coffee, and the specific brewing process is not described.

When coffee is brewed, the coffee solution mixed with the coffee powder is brewed into the coffee brewing chamber 510 from the lower part of the filter screen 3 of the brewing head, the sealing body 53 is pushed open, so that the coffee brewing chamber 510 is opened, and the coffee solution is discharged from the outlet at the top end of the coffee brewing chamber 510.

In the process of brewing coffee, the pressure spring pressure of the plug pressure spring 43 ensures that the plug 42 always props against the step surface of the flushing port 21, so that the flushing cavity 410 is closed, and the flushing cavity is prevented from flowing into a flushing channel when making coffee or cleaning.

When needs wash the use, pull down brewing chamber 9 to place a water collector in the below of boiling head body 1, wash chamber 410 in towards through washing hose 4100 and wash flush fluid (generally hot water), the flush fluid gets into washes the chamber 410 back, the pressure of flush fluid backs down end cap pressure spring 43 and flows into boiling head base 2, then flows out from boiling head filter screen 3, sets up the water collector in the below of boiling head body 1, and the waste water that flows out in the filter screen 3 of boiling head is taken away by the water collector. Meanwhile, the coffee brewing chamber 510 is sealed by the coffee pressure accumulating spring 51 and the sealing body 53, and the top opening force of the flushing liquid is ensured to be less than the elastic force of the coffee pressure accumulating spring 51, so that the flushing liquid cannot flow into the coffee brewing chamber 510.

In the process of brewing coffee, the coffee solution passes through the filter screen 3 of the brewing head, which is also the process of washing the filter screen 3 of the brewing head, namely washing in the positive direction of the filter screen 3 of the brewing head, the plugging holes in the filter screen 3 of the brewing head are loosened after being soaked by tablets (coffee solution), and the part of the coffee solution loosened after being washed in the positive direction.

The flushing fluid washes towards first filter screen 3 of boiling and realizes the backwash of first filter screen 3 of boiling, carries out the opposite direction and washs, can receive more ideal effect, need not carry out manual dismantlement again and carries out artificial operation, has alleviateed intensity of labour, promotes efficiency by a wide margin.

Example 2:

in this embodiment, the back-flushing channel 41 is integrated with the brewing head base 2, the coffee outlet channel 22 is sealingly connected to the brewing head base 2, and the rest of the structure is arranged as in embodiment 1.

Example 3:

in this embodiment, the back-flush channel 41 and the coffee outlet channel 22 are both formed integrally with the brewing head base 2, and the rest of the structure is mounted as in embodiment 1.

Example 4:

in this embodiment, the back-flushing channel 41 and the coffee outlet channel 22 are both made in a sealing connection with the brewing head base 2, and the rest of the construction is mounted in the same way as in embodiment 1.

The foregoing is only a preferred embodiment of this invention and it should be noted that modifications can be made by those skilled in the art without departing from the principle of the invention and these modifications should also be considered as the protection scope of the invention.