Bean grinding and powder discharging structure of coffee machine

Abstract

The utility model discloses a bean grinding and powder discharging structure of a coffee machine, which belongs to the technical field of coffee machines and comprises a machine body, a bean box component is arranged outside the machine body, a driving group and a bean grinding component are arranged on the bean box component, the driving group is fixedly arranged on the bean box component, the bean grinding component is detachably arranged on the bean box component, and the bean grinding component and the bean box component are arranged up and down during assembly. And a powder outlet is formed in the bottom of the bean grinding assembly, and a funnel is detachably arranged below the powder outlet. The bean box assembly and the bean grinding assembly of the structure are convenient to daily clean and maintain, in addition, coffee beans in the bean box assembly can directly enter the bean grinding assembly through the gravity of the coffee beans and are ground into coffee powder through driving of the driving set, and the coffee powder can be directly discharged through the powder outlet and falls into the funnel below the powder outlet; coffee powder can be directly discharged without assistance of a powder channel and a powder sweeping piece, so that effective powder discharging of the coffee powder is ensured, the problems of residues and blocking due to caking are avoided, and practicability is high.

Description

Technical Field

[0001] This utility model relates to the field of coffee machine technology, specifically a coffee machine grinding and powder dispensing structure. Background Technology

[0002] In existing pressure coffee machines, the grinding system is generally embedded inside the machine, and the relevant components are not exposed. When grinding coffee beans, the coffee powder is discharged from the side outlet towards the funnel, as shown in the utility model patent disclosed in Chinese Patent No. CN201820357345.6 and the invention patent disclosed in Chinese Patent No. CN201711123738.7.

[0003] However, the existing technology described above has an inclined dispensing channel that forms an angle with the grinding system. The larger the angle, the more coffee powder remains in the dispensing channel. Furthermore, a significant amount of coffee powder remains between the dust collector and the grinding disc in the grinding system. Moreover, the grinding system is difficult to disassemble and reassemble, making it impossible to clean away all the residual coffee powder. If left unused for an extended period, the coffee powder will absorb moisture and clump together, clogging the dispensing channel and causing dispensing difficulties, thus affecting the normal use of the product. Therefore, further improvements are necessary. Utility Model Content

[0004] The present invention aims to provide a coffee bean grinding and powder dispensing structure for a coffee machine to overcome the shortcomings of the prior art.

[0005] A coffee machine grinding and dispensing structure designed for this purpose includes a machine body, on which a bean hopper assembly is externally mounted. The bean hopper assembly is equipped with a drive unit and a grinding assembly. The drive unit is fixedly mounted on the bean hopper assembly. The grinding assembly is detachably mounted on the bean hopper assembly and is arranged vertically with the bean hopper assembly during assembly, and is drivenly connected to the drive unit. A powder outlet is provided at the bottom of the grinding assembly, and a funnel is detachably mounted below the powder outlet.

[0006] The machine body is provided with a funnel support, which is located below the grinding assembly, and the funnel is attached to and detached from the funnel support.

[0007] The machine body is provided with a fixed bracket. The bean box assembly includes a bean box. The drive assembly includes a motor bracket and a motor. The motor bracket is located inside the bean box and has a connecting arm extending from its outer side. The side of the bean box is provided with a wall opening corresponding to the connecting arm. The connecting arm extends towards the wall opening and is fixedly connected to the fixed bracket. The motor bracket is provided with a motor assembly cavity. The motor assembly cavity is independent of the bean box. The motor is fixedly installed in the motor assembly cavity, and its drive end faces the powder outlet and is driven by a gear transmission box. The gear transmission box is driven by the grinding assembly.

[0008] The bean box assembly also includes a bean box top cover and a bean box bottom shell. The bean box top cover is detachably installed on the top of the bean box, and the bean box bottom shell is fixedly installed on the bottom of the bean box. The drive group also includes a gear transmission box bottom cover, which is fixedly installed on the bottom of the gear transmission box.

[0009] The grinding assembly includes a pressing ring, a drive shaft, a conical blade, a grinding disc assembly, a rear cover, and a sealing cover. The pressing ring is screw-on and detachably mounted on the bottom shell of the bean container. The drive shaft is rotatably mounted on the pressing ring, with its upper end passing through the bottom cover of the gear transmission box and connected to the gear transmission box. The lower end of the drive shaft is rotatably mounted on the rear cover and driven by the conical blade. The rear cover is fixedly mounted on the pressing ring. The grinding disc assembly is located between the pressing ring and the rear cover. The conical blade rotates within the grinding disc assembly under the drive of the drive shaft. The sealing cover is fixedly mounted on the rear cover and has the powder outlet on it.

[0010] The bottom shell of the bean box is provided with an opening that communicates with the interior of the bean box. The pressing ring is provided with a pressing ring opening. The pressing ring opening is inclined toward the interior of the grinding disc assembly and communicates with the opening of the bottom shell of the bean box. The rear cover is provided with a rear cover opening. The interior of the grinding disc assembly, the rear cover opening, and the powder outlet are interconnected.

[0011] The grinding assembly also includes a conical chuck, the pressing ring is provided with an adapter hole, the conical chuck is provided with a conical chuck rotating hole, the conical chuck is drivenly connected to the conical chuck and is provided with a conical chuck driving hole, and the drive shaft passes through the adapter hole and the conical chuck rotating hole in sequence and is drivenly connected to the conical chuck driving hole.

[0012] The upper end of the drive shaft is provided with a positioning ring and is positioned on the adapter hole by the positioning ring. The lower end of the drive shaft is connected with a nut and is positioned on the conical cutter chuck by the nut.

[0013] The upper and lower ends of the adapter hole are respectively provided with oil-impregnated bearings and rotating balls. The rear cover is provided with chuck balls and ball bearings. The drive shaft is rotatably engaged with the upper oil-impregnated bearing and the rotating balls through the positioning ring. The top of the conical cutter is rotatably engaged with the lower oil-impregnated bearing and the rotating balls. The bottom of the conical cutter chuck is rotatably engaged with the chuck balls. The lower end of the drive shaft is rotatably engaged with the ball bearings.

[0014] The grinding disc assembly includes a grinding disc, a grinding disc positioning bracket, and a grinding disc rotating bracket. The grinding assembly also includes an adjusting ring, which is positioned and rotated between the pressing block ring and the rear cover. The inner wall of the adjusting ring is provided with adjusting annular internal teeth. The outer periphery of the grinding disc rotating bracket is provided with grinding disc rotating bracket annular external teeth, and the inner wall is provided with an internal thread. The grinding disc is fixed on the grinding disc positioning bracket, and the outer periphery of the grinding disc positioning bracket is provided with an external thread. The adjusting annular internal teeth mesh with the grinding disc rotating bracket annular external teeth for transmission, and the internal thread and the external thread are threadedly driven.

[0015] This invention, through structural improvements, places the bean hopper assembly externally on the machine body, and fixes the drive unit and detachable grinding assembly inside the bean hopper assembly. This allows the grinding assembly to be easily detached from the bean hopper assembly, facilitating daily cleaning and maintenance of both the bean hopper and grinding assembly. Furthermore, after assembly, the grinding assembly is positioned vertically above the bean hopper assembly and driven by the drive unit, allowing coffee beans inside the bean hopper assembly to directly enter the grinding assembly under their own weight and be ground into coffee powder by the drive unit. The bottom of the grinding assembly has a powder outlet, through which coffee powder can be directly dispensed and falls into a funnel below the outlet. This allows coffee powder to be dispensed directly without the need for a powder channel or sweeping device, effectively avoiding the problems of coffee powder residue and clumping that arise in existing technologies requiring a powder channel and sweeping device. This ensures efficient coffee powder dispensing and is highly practical. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the assembly structure of an embodiment of the present utility model.

[0017] Figure 2 This is a schematic diagram of the assembly cross-sectional structure of an embodiment of the present invention.

[0018] Figure 3 This is a breakdown view of the bean container assembly and the bean grinder assembly.

[0019] Figure 4 for Figure 3 A magnified structural diagram at point X in the diagram.

[0020] Figure 5 for Figure 3 A magnified structural diagram at point Y in the diagram.

[0021] Figure 6 This is a schematic diagram of the dissected structure of the bean box assembly.

[0022] Figure 7 This is a schematic diagram of the breakdown structure of the coffee grinder assembly. Detailed Implementation

[0023] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] See Figures 1-7 The coffee machine's grinding and dispensing structure includes a body 1, an external bean hopper assembly A on the body 1, a drive unit and a grinding assembly B on the bean hopper assembly A, the drive unit being fixedly mounted on the bean hopper assembly A, the grinding assembly B being detached and mounted on the bean hopper assembly A and arranged vertically with the bean hopper assembly A during assembly, and being driven and connected to the drive unit, the bottom of the grinding assembly B having a powder outlet 2, and a funnel 3 being detached and mounted below the powder outlet 2.

[0026] In this embodiment, the bean container assembly A is externally mounted on the machine body 1, and a drive unit and a detachable grinding assembly B are fixed inside the bean container assembly A. This allows the grinding assembly B to be easily detached from the bean container assembly A, facilitating daily cleaning and maintenance of both the bean container assembly A and the grinding assembly B. After assembly, the grinding assembly B is arranged vertically above the bean container assembly A and is driven by the drive unit. This allows the coffee beans in the bean container assembly A to directly enter the grinding assembly B by their own gravity and be ground into coffee powder by the drive unit. Furthermore, the bottom of the grinding assembly B is provided with a powder outlet 2, through which the coffee powder can be directly dispensed and fall into the funnel 3 below the powder outlet 2. This allows the coffee powder to be dispensed directly without the need for a powder channel or a powder sweeper, effectively avoiding the problems of coffee powder residue and clumping that occur in existing technologies that require a powder channel and a powder sweeper. This ensures efficient coffee powder dispensing and is highly practical.

[0027] In addition to holding coffee beans, bean box assembly A is also the main carrier of the drive unit and grinding assembly B. The drive unit and grinding assembly B are both set on bean box assembly A and form an integral module.

[0028] The machine body 1 is equipped with a funnel support 4, which is located below the coffee grinding component B. The funnel 3 is attached to the funnel support 4 so that the user can place the funnel 3 on the funnel support 4 and receive the coffee powder.

[0029] The machine body 1 is provided with a fixed bracket 5. The bean box assembly A includes a bean box 6, and the drive group includes a motor bracket 7 and a motor 8. The motor bracket 7 is located inside the bean box 6, and a connecting arm 9 extends from its outer side. The side of the bean box 6 is provided with a wall opening corresponding to the connecting arm 9. The connecting arm 9 extends towards the wall opening and is fixedly connected to the fixed bracket 5, thereby realizing the external fixation of the bean box 6 and the motor bracket 7.

[0030] The motor bracket 7 is provided with a motor assembly cavity, which is independent of the bean box 6. The motor 8 is fixedly installed in the motor assembly cavity, with its drive end facing the powder outlet 2, and is connected to a gear transmission box 10. The gear transmission box 10 is connected to the bean grinding component B.

[0031] The independent motor assembly chamber and bean box 6 can prevent coffee beans in bean box 6 from entering the motor assembly chamber and affecting the assembly of motor 8. In addition, the drive end of motor 8 faces the powder outlet 2, that is, motor 8 is inverted and the center of gravity is downward, making the operation more stable.

[0032] The bean container assembly A also includes a bean container top cover 11 and a bean container bottom shell 12. The bean container top cover 11 is detachable and installed on the top of the bean container 6, allowing the user to place coffee beans into the bean container 6 by removing and installing the bean container top cover 11. The bean container bottom shell 12 is fixedly installed at the bottom of the bean container 6, thereby forming a cavity for placing coffee beans inside the bean container 6. The drive assembly also includes a gear transmission box bottom cover 13, which is fixedly installed at the bottom of the gear transmission box 10 to cover the transmission gears inside the gear transmission box 10.

[0033] The grinding assembly B includes a pressing ring 14, a drive shaft 15, a conical blade 16, a grinding disc assembly, a rear cover 17, and a sealing cover 18. The pressing ring 14 is screwed onto the bottom shell 12 of the bean container, thereby allowing the entire grinding assembly B to be screwed onto the bottom shell 12 of the bean container for easy assembly and disassembly.

[0034] The drive shaft 15 is rotatably mounted on the pressing ring 14, and its upper end passes through the bottom cover 13 of the gear transmission box and is connected to the gear transmission box 10 for transmission, so that the gear transmission box 10 can transmit the power of the motor 8 to the drive shaft 15. The lower end of the drive shaft 15 is rotatably mounted on the rear cover 17 and is drivenly connected to the conical cutter 16. The rear cover 17 is fixedly mounted on the pressing ring 14. The grinding disc assembly is located between the pressing ring 14 and the rear cover 17. The conical cutter 16 rotates in the grinding disc assembly driven by the drive shaft 15. The cooperation between the conical cutter 16 and the grinding disc assembly can achieve the grinding of coffee beans. The sealing cover 18 is fixedly mounted on the rear cover 17 and has a powder outlet 2. The setting of the sealing cover 18 can ensure that the coffee powder on the rear cover 17 will not fly away, and ensure that the coffee powder is discharged from the powder outlet 2.

[0035] The bottom shell 12 of the bean box is provided with an opening 19 that communicates with the inside of the bean box 6. The pressing ring 14 is provided with a pressing ring opening 20. The pressing ring opening 20 is inclined toward the inside of the grinding disc assembly and communicates with the opening 19 of the bottom shell of the bean box. The rear cover 17 is provided with a rear cover opening 21. The inside of the grinding disc assembly, the rear cover opening 21, and the powder outlet 2 are interconnected.

[0036] In this embodiment, the coffee beans in the bean box 6 enter between the conical blade 16 and the grinding disc assembly through the bottom shell opening 19 and the pressing ring opening 20, and are ground into coffee powder. The coffee powder is then discharged from the rear cover opening 21 and the powder outlet 2. The entire process of grinding the coffee beans and discharging the coffee powder is carried out by gravity, which has a short travel distance and does not cause any residue or blockage.

[0037] The grinding assembly B also includes a conical chuck 22, a transition hole on the pressing ring 14, a conical chuck rotating hole 23 on the conical chuck 16, a conical chuck 22 that is connected to the conical chuck 16 and has a conical chuck transmission hole 24, and a drive shaft 15 that passes through the transition hole and the conical chuck rotating hole 23 in sequence and is connected to the conical chuck transmission hole 24.

[0038] In this embodiment, when the drive shaft 15 rotates, it drives the conical cutter chuck 22 to rotate, and when the conical cutter chuck 22 rotates, it also drives the conical cutter 16 to rotate.

[0039] The upper end of the drive shaft 15 is provided with a positioning ring 25, which is positioned on the adapter hole. The lower end of the drive shaft 15 is connected with a nut 26, which is positioned on the conical cutter chuck 22. In this way, both the upper and lower ends of the drive shaft 15 can be positioned, ensuring that the drive shaft 15 will not move up and down when rotating.

[0040] The upper and lower ends of the adapter hole are respectively equipped with oil-impregnated bearings 27 and rotating balls 28. The rear cover 17 is equipped with chuck balls 29 and ball bearings 30. The drive shaft 15 is rotatably engaged with the upper oil-impregnated bearings 27 and rotating balls 28 through the positioning ring 25. The top of the conical cutter 16 is rotatably engaged with the lower oil-impregnated bearings 27 and rotating balls 28. The bottom of the conical cutter chuck 22 is rotatably engaged with the chuck balls 29. The lower end of the drive shaft 15 is rotatably engaged with the ball bearings 30. In this way, the drive shaft 15, conical cutter 16, and conical cutter chuck 22 are on the same axis and can all achieve stable rotation. During rotation, they will not rub against the pressure block ring 14 and the rear cover 17. At the same time, it can also prevent the drive shaft 15, conical cutter 16, and conical cutter chuck 22 from swaying or moving up and down during rotation, thereby improving the stability and service life of the product.

[0041] The grinding disc assembly includes a grinding disc 31, a grinding disc positioning bracket 32, and a grinding disc rotating bracket 33. The grinding bean assembly B also includes an adjusting ring 34, which is positioned and rotated between the pressing block ring 14 and the rear cover 17. The inner wall of the adjusting ring 34 is provided with adjusting annular internal teeth 35. The outer periphery of the grinding disc rotating bracket 33 is provided with grinding disc rotating bracket annular external teeth 36, and the inner wall is provided with an internal thread portion 37. The grinding disc 31 is fixed on the grinding disc positioning bracket 32, and the outer periphery of the grinding disc positioning bracket 32 ​​is provided with an external thread portion 38. The adjusting annular internal teeth 35 and the grinding disc rotating bracket annular external teeth 36 mesh and drive each other, and the internal thread portion 37 and the external thread portion 38 drive each other by thread.

[0042] When in use, the user can drive the adjusting ring 34 to rotate. When the adjusting ring 34 rotates, it drives the grinding disc rotating bracket 33 to rotate together through the cooperation of the adjusting inner ring tooth 35 and the grinding disc rotating bracket outer ring tooth 36. When the grinding disc rotating bracket 33 rotates, it drives the grinding disc positioning bracket 32 ​​to move up and down through the cooperation of the inner thread part 37 and the outer thread part 38. Thus, when the grinding disc positioning bracket 32 ​​moves up and down, it drives the grinding disc 31 to move up and down together, so as to adjust the position between the grinding disc 31 and the conical cutter 16, thereby realizing the adjustment of the grinding fineness of coffee beans.

[0043] In this embodiment, the main body 1 is also equipped with a steam component C, a water tank 39, a heating pot 40, and a water pump 41. The steam component C is mainly used for frothing milk and heating milk with steam. The heating pot 40 is connected to the steam component C. The water tank 39 is a water container, which is connected to the heating pot 40 and the water pump 41 through pipes. In addition, the main body 1 is also equipped with an electronic control board, which includes a control panel 43 and a power board. The power board is electrically connected to the control panel 43, the motor 8, the heating pot 40, and the water pump 41. The user can control the power board through the control panel 43 and control the motor 8, the heating pot 40, and the water pump 41 through the power board.

[0044] The above describes the preferred embodiments of this utility model, illustrating and describing its basic principles, main features, and advantages. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made without departing from the spirit and scope of this utility model, and all such changes and modifications fall within the scope of protection of this utility model as defined by the appended claims and their equivalents.

Claims

1. A coffee grinder and powder dispensing structure for a coffee machine, comprising a body (1), characterized in that: The machine body (1) is externally equipped with a bean box assembly (A). The bean box assembly (A) is equipped with a drive group and a grinding assembly (B). The drive group is fixedly installed on the bean box assembly (A). The grinding assembly (B) is disassembled and installed on the bean box assembly (A) and arranged vertically with the bean box assembly (A) during assembly. It is driven and connected to the drive group. The bottom of the grinding assembly (B) is provided with a powder outlet (2). A funnel (3) is disassembled and installed below the powder outlet (2).

2. The coffee bean grinding and powder dispensing structure of the coffee machine according to claim 1, characterized in that: The machine body (1) is provided with a funnel support (4), which is located below the grinding assembly (B). The funnel (3) is attached to and removed from the funnel support (4).

3. The coffee bean grinding and powder dispensing structure of the coffee machine according to claim 1, characterized in that: The machine body (1) is provided with a fixed bracket (5), the bean box assembly (A) includes a bean box (6), and the drive group includes a motor bracket (7) and a motor (8); wherein, the motor bracket (7) is located inside the bean box (6) and a connecting arm (9) extends outward from it, the side of the bean box (6) is provided with a wall opening corresponding to the connecting arm (9), the connecting arm (9) extends toward the wall opening and is fixedly connected to the fixed bracket (5), the motor bracket (7) is provided with a motor assembly cavity, the motor assembly cavity is independent of the bean box (6), the motor (8) is fixedly installed in the motor assembly cavity, and its driving end faces the powder outlet (2) and is driven by a gear transmission box (10), the gear transmission box (10) is connected to the grinding assembly (B).

4. The coffee bean grinding and powder dispensing structure of the coffee machine according to claim 3, characterized in that: The bean box assembly (A) also includes a bean box top cover (11) and a bean box bottom shell (12). The bean box top cover (11) is detachably installed on the top of the bean box (6), and the bean box bottom shell (12) is fixedly installed on the bottom of the bean box (6). The drive group also includes a gear transmission box bottom cover (13), which is fixedly installed on the bottom of the gear transmission box (10).

5. The coffee bean grinding and powder dispensing structure of the coffee machine according to claim 4, characterized in that: The grinding assembly (B) includes a pressing ring (14), a drive shaft (15), a conical blade (16), a grinding disc assembly, a rear cover (17), and a sealing cover (18). The pressing ring (14) is screwed onto the bottom shell (12) of the bean box. The drive shaft (15) is rotatably mounted on the pressing ring (14), and its upper end passes through the bottom cover (13) of the gear transmission box and is connected to the gear transmission box (10). The lower end of the drive shaft (15) is rotatably mounted on the rear cover (17) and is driven to connect with the conical blade (16). The rear cover (17) is fixedly mounted on the pressing ring (14). The grinding disc assembly is located between the pressing ring (14) and the rear cover (17). The conical blade (16) rotates within the grinding disc assembly under the drive of the drive shaft (15). The sealing cover (18) is fixedly mounted on the rear cover (17) and has the powder outlet (2) on it.

6. The coffee bean grinding and powder dispensing structure of the coffee machine according to claim 5, characterized in that: The bottom shell (12) of the bean box is provided with an opening (19) that communicates with the inside of the bean box (6). The pressing ring (14) is provided with an opening (20). The opening (20) of the pressing ring is inclined toward the inside of the grinding disc assembly and communicates with the opening (19) of the bottom shell of the bean box. The rear cover (17) is provided with an opening (21). The inside of the grinding disc assembly, the opening (21) of the rear cover, and the powder outlet (2) are interconnected.

7. The coffee bean grinding and powder dispensing structure of the coffee machine according to claim 5, characterized in that: The grinding assembly (B) also includes a conical chuck (22), the pressing ring (14) is provided with a transition hole, the conical chuck (16) is provided with a conical chuck rotating hole (23), the conical chuck (22) is connected to the conical chuck (16) in a driving connection and is provided with a conical chuck driving hole (24), the drive shaft (15) passes through the transition hole and the conical chuck rotating hole (23) in sequence and is driven connected to the conical chuck driving hole (24).

8. The coffee bean grinding and powder dispensing structure of the coffee machine according to claim 7, characterized in that: The upper end of the drive shaft (15) is provided with a positioning ring (25) and is positioned on the adapter hole by the positioning ring (25). The lower end of the drive shaft (15) is connected with a nut (26) and is positioned on the conical cutter chuck (22) by the nut (26).

9. The coffee bean grinding and powder dispensing structure of the coffee machine according to claim 8, characterized in that: The upper and lower ends of the adapter hole are respectively provided with an oil-impregnated bearing (27) and a rotating ball (28). The rear cover (17) is provided with a chuck ball (29) and a ball bearing (30). The drive shaft (15) is rotatably engaged with the upper oil-impregnated bearing (27) and the rotating ball (28) through the positioning ring (25). The top of the conical cutter (16) is rotatably engaged with the lower oil-impregnated bearing (27) and the rotating ball (28). The bottom of the conical cutter chuck (22) is rotatably engaged with the chuck ball (29). The lower end of the drive shaft (15) is rotatably engaged with the ball bearing (30).

10. The coffee bean grinding and powder dispensing structure of the coffee machine according to claim 7, characterized in that: The grinding disc assembly includes a grinding disc (31), a grinding disc positioning bracket (32), and a grinding disc rotating bracket (33). The grinding bean assembly (B) also includes an adjusting ring (34). The adjusting ring (34) is positioned and rotated between the pressing block ring (14) and the rear cover (17). The inner wall of the adjusting ring (34) is provided with adjusting annular inner teeth (35). The outer periphery of the grinding disc rotating bracket (33) is provided with grinding disc rotating bracket annular outer teeth (36), and the inner wall is provided with an internal thread (37). The grinding disc (31) is fixed on the grinding disc positioning bracket (32). The outer periphery of the grinding disc positioning bracket (32) is provided with an external thread (38). The adjusting annular inner teeth (35) mesh with the grinding disc rotating bracket annular outer teeth (36) for transmission, and the internal thread (37) and the external thread (38) are threadedly driven.

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