Nozzle for oral cavity cleaning device and oral cavity cleaning device

Abstract

The invention provides a nozzle for an oral cavity cleaning device and the oral cavity cleaning device, which can further improve the cleaning effect in the oral cavity. A nozzle (4) for an oral cavity cleaning device according to the present disclosure is provided with a nozzle housing (40) in which a flow path (P1) is formed, the flow path (P1) having an inlet (P1a) and an outlet (P1b). Furthermore, the nozzle (4) for an oral cavity cleaning device is configured so that a fluid having a pressure of 1-4 MPa (inclusive) is introduced into the flow path (P1) from the inlet (P1a), and is discharged from the discharge port (P1b) with a discharge load of 0.19-0.38 N. The nozzle (4) for an oral cavity cleaning device is configured so that the fluid is discharged from the discharge port (P1b) with a discharge load of 0.19-0.38 N.

Description

Technical Field

[0001] This invention relates to a nozzle for an oral cleaning device and an oral cleaning device. Background Technology

[0002] As disclosed in Patent Document 1, a nozzle for an oral cleaning device is known to include a flow path structure, which has a flow path including an inlet and an outlet. In the nozzle for an oral cleaning device disclosed in Patent Document 1, the flow path structure includes: a first structure including a first flow path; and a second structure located downstream of the first structure, including a second flow path narrower than the first flow path. Furthermore, the flow path structure includes: a third structure located downstream of the second structure, including a third flow path wider than the second flow path; and a fourth structure located downstream of the third structure, including a fourth flow path.

[0003] Furthermore, a narrowing section is formed in the fourth flow path to narrow the flow path, and the downstream side of this narrowing section is formed to widen as it moves from the narrowing section side toward the outlet side. This causes cavitation of the cleaning fluid, thereby improving the cleaning effect in the oral cavity.

[0004] Prior art literature

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2018-126283 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] Thus, the existing technology can improve the cleaning effect in the oral cavity, but further improvements in the cleaning effect in the oral cavity are expected.

[0009] Therefore, the object of the present invention is to provide a nozzle for an oral cleaning device and an oral cleaning device that can further improve the cleaning effect in the oral cavity.

[0010] Solutions for solving problems

[0011] One aspect of the oral cleaning device disclosed herein includes a nozzle housing having a flow path having an inlet and an outlet. The nozzle is configured such that fluid with a pressure of 1 MPa or more and 4 MPa or less is introduced into the flow path from the inlet and discharged from the outlet with a discharge load of 0.19 N or more and 0.38 N or less.

[0012] One aspect of the oral cleaning device disclosed herein includes: the above-described oral cleaning device nozzle; and a holding portion to which the oral cleaning device nozzle is detachably mounted.

[0013] The effects of the invention

[0014] According to this disclosure, it is possible to obtain a nozzle for an oral cleaning device and an oral cleaning device that can further improve the cleaning effect in the oral cavity. Attached Figure Description

[0015] Figure 1 This is a schematic diagram illustrating one example of an oral cleaning device according to an embodiment.

[0016] Figure 2 This is a schematic diagram illustrating the pump and pump drive mechanism of an oral cleaning device according to an embodiment.

[0017] Figure 3 This is a perspective view of the piston-driven pump mechanism of the oral cleaning device according to one embodiment, viewed from one direction.

[0018] Figure 4 This is a perspective view of the piston-driven pump mechanism of the oral cleaning device according to another embodiment.

[0019] Figure 5 This is a side view of the piston-driven pump mechanism of the oral cleaning device according to an embodiment.

[0020] Figure 6 This is a top view showing the piston-driven pump mechanism of the oral cleaning device according to an embodiment.

[0021] Figure 7 It is along Figure 6 A cross-sectional view along line AA.

[0022] Figure 8 This graph compares the piston displacement and liquid delivery rate with those of a typical pump when the delivery process takes less time than the suction process.

[0023] Figure 9 This graph compares the current value of a motor with an auxiliary mechanism and the current value of a motor without an auxiliary mechanism.

[0024] Figure 10 This is a side view showing an example of a nozzle in an embodiment.

[0025] Figure 11 This is a diagram showing an example of a nozzle in an embodiment, and is a longitudinal sectional view obtained by cutting along a plane along the flow path axis.

[0026] Figure 12 This diagram illustrates the configuration relationship between the first narrowing flow path and the widening flow path of an example nozzle in an embodiment.

[0027] Figure 13 This is a diagram illustrating an example of a method for measuring the pressure inside a nozzle.

[0028] Figure 14 This is a graph showing the relationship between the pressure inside the nozzle of the embodiment and the load of the discharged water volume.

[0029] Figure 15 This is a graph showing the relationship between the distance from the tip to the dirt surface of the nozzle in the embodiment and the amount of dirt removed.

[0030] Figure 16 This is a graph showing the relationship between the discharge flow rate and the amount of dirt removed from the nozzles of the embodiments and the nozzles of the comparative examples.

[0031] Figure 17 This is a diagram showing an example of a nozzle in an embodiment, and is a cross-sectional view obtained by cutting with a plane orthogonal to the flow path axis.

[0032] Figure 18 This is a diagram illustrating an example of a nozzle manufacturing method, and a cross-sectional view showing the state in which the first forming member and the second forming member are prepared.

[0033] Figure 19 This is a diagram illustrating an example of a nozzle manufacturing method, and a cross-sectional view showing the state in which the first forming member and the second forming member are stacked together.

[0034] Figure 20 The diagram shows an example of a nozzle manufacturing method, and is a cross-sectional view showing a state in which a joining member is formed in the inflow space formed by the overlapping of a first forming member and a second forming member using a mold.

[0035] Figure 21 This is a diagram showing an example of a nozzle in an embodiment, and is a cross-sectional view obtained by cutting the portion where the first narrow flow path exists with a plane orthogonal to the flow path axis.

[0036] Figure 22 This is a diagram showing a first modified example of the nozzle according to the embodiment. It is a cross-sectional view obtained by cutting with a plane orthogonal to the flow path axis.

[0037] Figure 23 This is a diagram showing a second modified example of the nozzle according to the embodiment. It is a cross-sectional view obtained by cutting with a plane orthogonal to the flow path axis.

[0038] Figure 24 This is a schematic diagram illustrating an example of a nozzle that can be manufactured using a nozzle manufacturing method.

[0039] Figure 25This is a schematic diagram illustrating an example of the external shape and flow path shape of a nozzle that can be manufactured by an example of a nozzle manufacturing method.

[0040] Figure 26 This is a schematic diagram illustrating another example of the appearance and flow path shape of a nozzle that can be manufactured by one example of a nozzle manufacturing method.

[0041] Figure 27 This is a schematic diagram illustrating an example of the appearance and cross-sectional shape of a nozzle that can be manufactured by a nozzle manufacturing method.

[0042] Figure 28 This is a schematic diagram illustrating another example of the appearance and cross-sectional shape of a nozzle that can be manufactured by a nozzle manufacturing method.

[0043] Figure 29 This is a perspective view of the oral cleaning device of the first modified embodiment, viewed from one direction.

[0044] Figure 30 This is a perspective view of the oral cleaning device of the first modified embodiment, viewed from another direction.

[0045] Figure 31 This is a perspective view showing the gripping part and nozzle of the first modified embodiment.

[0046] Figure 32 This is a diagram schematically illustrating a second variation of the oral cleaning device according to the embodiment. Detailed Implementation

[0047] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. However, sometimes unnecessary detailed descriptions are omitted. For example, detailed descriptions of matters that are already known may be omitted, or descriptions of substantially the same structures may be repeated.

[0048] Furthermore, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand this disclosure, and are not intended to limit the subject matter of the claims.

[0049] Furthermore, in the following embodiments, the vertical direction of the oral cleaning device will be defined as follows, with the tip of the nozzle facing upwards and the extension direction of the rod aligned with the vertical direction. Additionally, the direction in which liquid is discharged from the discharge section will be defined as the forward direction.

[0050] (Implementation Method)

[0051] The following describes the nozzle and oral cleaning device of the embodiment.

[0052] Figure 1This is a schematic diagram illustrating one example of an oral cleaning device 100 according to an embodiment. (As shown) Figure 1 As shown, the oral cleaning device 100 of this embodiment includes a liquid storage tank 2 (i.e., an example of a liquid storage section), a device body 3, and a nozzle 4.

[0053] The liquid storage tank 2 is formed as a bottomed cylindrical shape that opens upwards and closes at the lower end. Inside the liquid storage tank 2, a storage section 2a is formed for storing liquid. Furthermore, water can be used as the liquid stored in the storage section 2a, but it is not limited to water; various liquids can be used. For example, a cleaning solution containing a cleaning agent mixed with water can be used.

[0054] Furthermore, in this embodiment, the liquid storage tank 2 is detachably mounted to the device body 3, allowing it to be cleaned while detached from the device body 3. This makes it possible to keep the liquid storage tank 2 cleaner. Such a liquid storage tank 2 can be formed, for example, from polypropylene resin, so that it can be washed in a dishwasher.

[0055] In this embodiment, the liquid storage tank 2 includes a generally cylindrical body 21 with openings at the top and bottom, and a bottom wall 22 that closes the lower opening of the cylindrical body 21. Furthermore, a liquid supply hole (not shown) is formed on the side of the liquid storage tank 2 (more specifically, the cylindrical body 21) for injecting liquid into the storage section 2a; this liquid supply hole is closed by a liquid supply cap 211. Therefore, when the liquid storage tank 2 is installed on the device body 3, liquid can be supplied to the storage section 2a within the liquid storage tank 2.

[0056] On the other hand, the main body 3 of the device includes a shell 31 (i.e., an example of an outer casing) that forms its outer shape. This shell 31 is a generally cylindrical shape that is elongated in the vertical direction, and the main structural elements such as the pump 33, which will be described later, are housed inside the cylinder of the shell 31. In addition, the shell 31 tapers approximately to its center in the longitudinal direction, forming a shape that is easy for the user to hold in their hand when using the oral cleaning device 100. Therefore, in this embodiment, the taper portion of the shell 31 in the longitudinal direction becomes a grip portion 10 that the user can hold in their hand.

[0057] In this embodiment, the housing 31 includes: a top wall 311; a generally cylindrical peripheral wall 312 extending downward from the outer periphery of the top wall 311; and a bottom wall 313 continuously disposed from the lower end of the peripheral wall 312.

[0058] A nozzle mounting portion 3111 is formed on the top wall 311, and a nozzle 4 is mounted on the nozzle mounting portion 3111 in a detachable manner. The nozzle 4 is formed as a hollow strip and is able to discharge (more specifically, spray out) liquid from the top.

[0059] In addition, the peripheral wall 312 is provided with a button (not shown) that allows the nozzle 4 to be removed from the housing 31 (i.e., an example of the device body 3), and a power switch (not shown) that allows the oral cleaning device 100 to be started or stopped (i.e., to switch the power supply of the oral cleaning device 100 on or off).

[0060] Furthermore, in this embodiment, an inwardly recessed portion 3121 is formed in the lower part of the peripheral wall 312, and the liquid storage tank 2 is installed in the recessed portion 3121 in a detachable manner.

[0061] Furthermore, with the reservoir 2 installed in the recess 3121, the bottom surface 221 of the bottom wall 22 of the reservoir 2 and the bottom surface 3131 of the bottom wall 313 of the housing 31 are approximately coplanar flat surfaces. As a result, when the oral cleaning device 100 is not in use, it can be placed in a position with the nozzle 4 facing upwards.

[0062] In addition, a liquid flow path 32 for supplying liquid stored in the liquid tank 2 to the nozzle 4 is formed inside the housing 31 (i.e., an example of the device body 3).

[0063] In this embodiment, the liquid flow path 32 includes a suction path 321 disposed on the upstream side of the liquid flow path 32 and a discharge path 322 disposed on the downstream side of the liquid flow path 32, and the suction path 321 and the discharge path 322 are connected via a pump 33. Thus, in this embodiment, a pump 33 is disposed in the middle of the liquid flow path 32. As such a pump 33, a piston pump can be used, for example. However, the type of pump is not particularly limited, and various types of pumps can be used.

[0064] In this embodiment, the suction path 321 is formed by a hollow tube 3211, such as a conduit, which penetrates the peripheral wall 312 and has its top end (more specifically, the upstream end) facing the recess 3121. Furthermore, a flexible tube 5A is installed at the top end (more specifically, the upstream end) of the tube 3211 facing the recess 3121, through which liquid stored in the storage tank 2 is supplied to the liquid flow path 32. Thus, by using the flexible tube 5A, the storage tank 2 can be smoothly loaded and unloaded from the device body 3.

[0065] In addition, the delivery path 322 is also formed by a hollow tube 3221, such as a conduit, which is formed to open upward through the top wall 311, and the top end (more specifically, the downstream end) of the tube 3221 is connected to the nozzle 4.

[0066] Thus, in this embodiment, the liquid flow path 32 is disposed within the housing 31 (i.e., within the device body 3) with one end communicating with the inner space of the nozzle mounting portion 3111 and the other end facing the recess 3121. Furthermore, a tube 5A is installed at the other end facing the recess 3121. Therefore, liquid introduced into the storage tank 2 via the tube 5A is supplied to the nozzle 4 through the liquid flow path 32.

[0067] Furthermore, in this embodiment, the tube 5A is integrally installed at the top end (more specifically, the upstream end) of the tube 3211. With the liquid storage tank 2 installed on the device body 3, the tube 5A is disposed within the storage section 2a of the liquid storage tank 2. The liquid stored in the storage section 2a is then introduced into the housing 31 (i.e., the device body 3) via the tube 5A.

[0068] Figure 2 This is a schematic diagram illustrating the pump 33 and pump drive mechanism 34 of the oral cleaning device 100 according to an embodiment. Figure 2 As shown, a pump drive mechanism 34 is disposed inside the housing 31 (i.e., an example of the device body 3). Furthermore, by using the pump drive mechanism 34 to operate the pump 33, the liquid in the storage section 2a is drawn up through the pipe 5A and discharged (more specifically, sprayed out) from the top of the nozzle 4 through the liquid flow path 32.

[0069] Thus, the oral cleaning device 100 of this embodiment includes a pump 33 and a pump drive mechanism 34 for driving the pump 33, and becomes a device for discharging liquid by driving the pump 33.

[0070] In addition, in this embodiment, the pump 33 includes: a pump chamber 333, a suction passage 321 and a discharge passage 322 communicating with the pump chamber 333; a cylinder 332 configured to communicate with the lower end of the pump chamber 333; and a piston 331 disposed within the cylinder 332.

[0071] In addition, a suction valve (not shown) is provided between the pump chamber 333 and the suction passage 321, and a discharge valve (not shown) is provided between the pump chamber 333 and the discharge passage 322.

[0072] The piston 331 is connected to the pump drive mechanism 34, and reciprocates linearly within the cylinder 332 in the vertical direction (i.e., an example of "one direction"). Furthermore, the volume of the pump chamber 333 changes due to the reciprocating linear motion of the piston 331 within the cylinder 332.

[0073] Specifically, when piston 331 moves downward within cylinder 332, the volume of pump chamber 333 increases, and liquid in reservoir 2 flows into pump chamber 333 via pipe 5A and suction passage 321. Then, with liquid flowing into pump chamber 333, when piston 331 moves upward within cylinder 332, the volume of pump chamber 333 decreases, and liquid in pump chamber 333 is supplied to nozzle 4 via discharge passage 322. The liquid supplied to nozzle 4 is then discharged (more specifically, ejected) from the tip of nozzle 4.

[0074] Thus, in this embodiment, the piston 331 moves downward within the cylinder 332 to perform a suction process, drawing liquid into the pump chamber 333, and moves upward to perform a delivery process, expelling liquid from the pump chamber 333 to the outside (more specifically, the nozzle 4). That is, the piston 331 reciprocates linearly between top dead center and bottom dead center, thereby alternately performing the suction and delivery processes. Therefore, when the piston 331 reciprocates once in the vertical direction from top dead center, the suction and delivery processes are each performed once.

[0075] By configuring the structure in this way, liquid is intermittently discharged from the top of the nozzle 4 installed on the main body 3 of the device.

[0076] Moreover, in this embodiment, such as Figures 2-7 As shown, the pump drive mechanism 34 includes a motor 341, which drives the piston 331 to reciprocate linearly in the vertical direction within the cylinder 332. Figure 3 This is a perspective view of the pump drive mechanism 34 with piston 331 of the oral cleaning device 100 according to one embodiment, viewed from one direction. Figure 4 This is a perspective view of the pump drive mechanism 34 with piston 331 of the oral cleaning device 100 in another embodiment, viewed from another direction. Figure 5 This is a side view of the pump drive mechanism 34 with piston 331 of the oral cleaning device 100 according to the embodiment. Figure 6 This is a top view of the pump drive mechanism 34 with piston 331 of the oral cleaning device 100 according to the embodiment. Figure 7 It is along Figure 6 A cross-sectional view along line AA.

[0077] Specifically, the pump drive mechanism 34 includes a motor 341 and a conversion mechanism 344 that converts the rotational motion of the motor 341 into reciprocating linear motion. Furthermore, a piston 331 is connected to this conversion mechanism 344, causing the piston 331 to reciprocate linearly in the vertical direction within the cylinder 332. The motor 341 is driven by power supplied from a battery (e.g., a rechargeable battery, dry cell battery, etc.) housed inside the device body 3, or by external power.

[0078] Furthermore, in this embodiment, the pump drive mechanism 34 includes a reduction mechanism 342 that reduces the rotational speed of the motor 341 and a transmission mechanism 343 that transmits the rotational motion reduced by the reduction mechanism 342 to the conversion mechanism 344. Therefore, in this embodiment, when the rotational speed of the motor 341 (i.e., revolutions per unit time) is reduced to a predetermined rotational speed (i.e., revolutions per unit time) by the reduction mechanism 342, it is converted into reciprocating linear motion by the conversion mechanism 344.

[0079] At this time, by adjusting the reduction ratio of the deceleration mechanism 342, the time taken for the piston 331 to reciprocate once (i.e., the time for one suction process and one discharge process) can be set to the desired time. Furthermore, considering the ease of use of the oral cleaning device 100, the piston pulse count (i.e., the number of reciprocations of the piston 331 per minute) is preferably 500 rpm to 3000 rpm. Therefore, the time taken for the piston 331 to reciprocate once (i.e., the time for one suction process and one discharge process), i.e., the time required for one cycle of the pump 33, is preferably 0.02 seconds to 0.12 seconds.

[0080] In this embodiment, such as Figures 3-7 As shown, the reduction mechanism 342 includes: a pinion 3421 mounted on the motor shaft 3411 of the motor 341 and rotating in conjunction with the rotation of the motor shaft 3411; and a reduction gear 3422 meshing with the pinion 3421. Furthermore, the reduction mechanism 342 includes a first output shaft 3423 supporting the reduction gear 3422 and rotating in conjunction with its rotation. Moreover, by setting the gear ratio between the pinion 3421 and the reduction gear 3422 to a predetermined value, the rotational speed (i.e., revolutions per unit time) of the motor 341 is reduced to a predetermined rotational speed (i.e., revolutions per unit time).

[0081] Furthermore, a transmission mechanism 343 is connected to the first output shaft 3423. Specifically, the transmission mechanism 343 includes a first transmission gear 3431 mounted on and rotating in conjunction with the rotation of the first output shaft 3423. Additionally, the transmission mechanism 343 includes a second transmission gear 3432 meshing with the first transmission gear 3431. Furthermore, the transmission mechanism 343 includes a second output shaft 3433 supporting the second transmission gear 3432 and rotating in conjunction with its rotation. Moreover, the rotation of the motor 341, which is reduced in speed by the reduction mechanism 342, is transmitted to the conversion mechanism 344 via the second output shaft 3433.

[0082] The conversion mechanism 344 includes a first gear 3441 mounted on and rotating in conjunction with the second output shaft 3433. Additionally, the conversion mechanism 344 includes a second gear 3442 meshing with the first gear 3441. Furthermore, the conversion mechanism 344 includes a third output shaft 3443 supporting the second gear 3442 and rotating in conjunction with it.

[0083] Furthermore, the conversion mechanism 344 includes: a cam 3444 mounted on the third output shaft 3443 and rotating in conjunction with the rotation of the third output shaft 3443; and a rod 3446 that reciprocates linearly in the vertical direction via the cam 3444. The cam 3444 is a component that converts the rotation of the motor 341 into axial operating force, and in this embodiment, it is fixed to the second gear 3442 by screws 3445. Moreover, the rod 3446 reciprocates linearly in the vertical direction along the device body 3 using the axial operating force converted by the cam 3444. Furthermore, as... Figure 2 As shown, it can also be configured such that the lever 3446 is directly (i.e., without via the cam) mounted on the second gear 3442.

[0084] Furthermore, a piston 331 is mounted at the top (more specifically, the upper end) of the rod 3446 via a connecting shaft 34461. Thus, the piston 331 reciprocates linearly in the vertical direction within the cylinder 332.

[0085] In this embodiment, the pump drive mechanism 34 includes an auxiliary mechanism 346 for assisting the movement of the piston 331.

[0086] The auxiliary mechanism 346 includes a spring seat 3461, a pair of shafts 3463 fixed to both ends of the spring seat 3461, and a sliding member 3464 mounted on the pair of shafts 3463 in a manner that allows it to slide axially. At this time, a pair of helical springs 3462 (i.e., an example of force-applying members) are respectively mounted on the pair of shafts 3463, and the sliding member 3464 is subjected to an upward force by the pair of helical springs 3462 (i.e., an example of force-applying members). Thus, in this embodiment, the auxiliary mechanism 346 includes helical springs 3462 (i.e., an example of force-applying members) that apply force to the piston 331 upwards (i.e., in the direction included by the term "a direction").

[0087] Furthermore, the pressing portion 34641 of the sliding member 3464 abuts against the lower end of the cylinder 332, and the elastic restoring force of a pair of coil springs 3462 (i.e., an example of a force-applying member) applies an upward force to the cylinder 332. In addition, the force-applying member can be any component that can be elastically deformed; not only springs such as coil springs can be used, but also components such as rubber can be used.

[0088] Furthermore, the pump drive mechanism 34 is not limited to the structure described above and can be configured in various ways. For example, the reduction gear 3422 and the first transmission gear 3431 can be integrated, or the second transmission gear 3432 and the first gear 3441 can be integrated. Alternatively, the second gear 3442 and the cam 3444 can be integrated.

[0089] Alternatively, it can be a pump drive mechanism 34 that does not have an auxiliary mechanism 346 for moving the auxiliary piston 331.

[0090] In this embodiment, oral cavity cleaning can be performed more efficiently.

[0091] Specifically, it includes a speed-changing mechanism 345 that makes the moving speed of the piston 331 during the pump drive mechanism 34 different from the moving speed of the piston 331 during the suction process. Furthermore, the piston 331 reciprocates once in such a way that the time spent in the suction process is shorter than the time spent in the discharge process.

[0092] In this embodiment, by employing a transmission mechanism 345 using non-circular gears, the moving speed of the piston 331 during the feeding process is different from the moving speed of the piston 331 during the suction process. That is, in this embodiment, the transmission mechanism 345 has non-circular gears. Specifically, the first gear 3441 and the second gear 3442 that mesh with each other are non-circular gears. These non-circular gears can be formed of a metal material or a resin material.

[0093] Furthermore, in this embodiment, an elliptical gear is used as a non-circular gear, and the transmission mechanism 345 has an elliptical gear as a non-circular gear. Specifically, the first gear 3441 that meshes with each other is set as an elliptical gear 3451, and the second gear 3442 is set as an elliptical gear 3452.

[0094] Furthermore, by appropriately setting the flatness of the elliptical gears 3451 and 3452, the installation position of the output shafts (more specifically, the second output shaft 3433 and the third output shaft 3443), and the gear ratio of the elliptical gears 3451 and 3452, the ratio of the time spent in the delivery process to the time spent in the suction process is made to be 1:X (here, X > 1). X is the value of the feed ratio. At this time, considering the cleaning effect in the oral cavity, it is preferable to set the feed ratio to a range of 1.5 to 5.0. That is, if the ratio of the time spent in the delivery process to the time spent in the suction process is set to 1:X, it is preferable to set the value of X to be 1.5 or more and 5.0 or less.

[0095] Thus, in this embodiment, the pump drive mechanism 34 includes a speed change mechanism 345 that makes the moving speed of the piston 331 during the discharge process different from the moving speed of the piston 331 during the suction process. Furthermore, the speed change mechanism 345 has non-circular gears (more specifically, a first gear 3441 and a second gear 3442). In addition, the speed change mechanism 345 may have only one non-circular gear, or it may have three or more non-circular gears.

[0096] Furthermore, in this embodiment, the transmission mechanism 345 has elliptical gears 3451 and 3452, which are non-circular gears, and the transmission mechanism 345 is composed of two elliptical gears 3451 and 3452. Alternatively, it may have only one elliptical gear or more than three elliptical gears.

[0097] Furthermore, non-circular gears are not limited to elliptical gears; various non-circular gears can be used. For example, they can be polygonal gears with rounded apex portions, or gears with concave sections.

[0098] Furthermore, in this embodiment, only a pair of elliptical gears are used to change the ratio of the time spent in the delivery process to the time spent in the suction process, so the time required for one cycle of pump 33 is the same as that of a normal pump 33 (more specifically, the case of using circular gears).

[0099] When the pump 33 is driven by the pump drive mechanism 34 configured in this way, the movement speed of the piston 331 during the discharge process (i.e., the absolute value of the movement speed) can be increased, and the movement speed of the piston 331 during the suction process (i.e., the absolute value of the movement speed) can be decreased. That is, the time spent in the discharge process can be shorter than the time spent in the suction process.

[0100] The result, such as Figure 8 As shown, compared to a typical pump where the ratio of time spent in the delivery process to time spent in the suction process is 1:1, the maximum delivery rate D can be increased. Figure 8 This is a graph comparing the piston displacement and liquid delivery rate when the time spent in the delivery process is shorter than the time spent in the suction process, with those of a typical pump. In this embodiment, the maximum delivery rate at the instant of the delivery process is defined as the maximum delivery rate D. That is, the time spent in the delivery process is divided equally into predetermined tiny time intervals that are infinitesimally close to zero, and the maximum delivery rate in each interval is defined as the maximum delivery rate D. Therefore, the delivery rate at each instant during the delivery process is depicted as follows: Figure 8 In the case of the chart shown, the value of the output at the top of the chart becomes the maximum output D.

[0101] Furthermore, in this embodiment, the total amount of liquid dispensed in the dispensing process is the same. Considering the cleaning efficiency in the oral cavity and the ease of use of the oral cleaning device 100, the total amount of liquid dispensed in the dispensing process is preferably 50 ml / min to 450 ml / min.

[0102] Thus, when using the oral cavity cleaning device 100 equipped with the pump drive mechanism 34 of this embodiment, the discharge of useless liquid that is not used for cleaning can be minimized, and oral cavity cleaning can be performed more efficiently. In addition, even if the total amount of liquid delivered per reciprocating stroke of the piston 331 is the same, the maximum delivery amount D can be increased. Therefore, the discharge pressure of the liquid discharged from the oral cavity cleaning device 100 is increased, and oral cavity cleaning can be performed more efficiently.

[0103] In this embodiment, as described above, the time spent in the delivery process is shorter than the time spent in the intake process. Therefore, in this embodiment, the auxiliary mechanism 346 assists the movement of the piston 331 in the delivery process, which is the process in which the piston reciprocates once less in both the delivery and intake processes.

[0104] In this way, during the delivery process where the piston 331 moves at a higher speed and the motor 341 loads more, the movement of the auxiliary piston 331 can be adjusted to reduce the load on the motor 341. However, if the auxiliary mechanism 346 is used, the load on the motor 341 decreases in the shorter process and increases in the longer process.

[0105] Therefore, when using such an auxiliary mechanism 346, it is preferable to appropriately set the timing of the auxiliary mechanism 346 assisting the movement of the piston 331 and the force assisted by the auxiliary mechanism 346. In this way, as... Figure 9 As shown, compared to the case without the auxiliary mechanism 346 (i.e., Figure 9 Compared to the case shown by the dashed line, in the case of using auxiliary mechanism 346 (i.e., Figure 9 In the case shown by the solid line, the current value of motor 341 can be reduced (i.e., the load applied to motor 341 is reduced). Figure 9 This graph compares the current value of the motor 341 with and without the auxiliary mechanism 346. Furthermore, the assistance ratio is preferably set in the range of 10 to 60. That is, the force assisted by the auxiliary mechanism 346 is preferably 10% to 60% of the motor output.

[0106] In addition, a piston pump with a time ratio of 1:1 between the delivery process and the suction process can also be used.

[0107] Additionally, the nozzle 4 includes a nozzle housing 40 having a flow path P1, which has an inlet P1a and an outlet P1b. The nozzle housing 40 includes: a connecting portion 41 having an inlet P1a at its lower end, detachably mounted to the holding portion 10; and a housing body 42 continuously disposed from the upper end of the connecting portion 41, having an outlet P1b at its top (more specifically, the upper end). Furthermore, in this embodiment, the nozzle housing 40 is formed to align with the long side axis (more specifically, the flow path axis C1 of the flow path P1, see below). Figure 17 The cross-sectional shape when cut by an orthogonal plane is approximately circular.

[0108] The housing body 42 is the portion protruding from the holding portion 10 (more specifically, the housing 31) with the connecting portion 41 inserted and fitted into the nozzle mounting portion 3111. The housing body 42 includes a rod portion 421 that is elongated in the vertical direction. Furthermore, the housing body 42 includes a bent portion 422, which is continuously disposed with the upper end of the rod portion 421 and bends in a direction intersecting the extending direction (i.e., the vertical direction) of the rod portion 421; and a top portion 423, which is continuously disposed with the top end of the bent portion 422. Thus, in this embodiment, the nozzle housing 40 (i.e., an element of the nozzle 4) has a bent-top shape.

[0109] In this embodiment, a nozzle 4, shaped as described above, is mounted on a holding portion 10 (more specifically, housing 31). The bent tip 423 is inserted into the oral cavity, and a pump 33 is driven, thereby supplying fluid from the reservoir 2 to the flow path P1 via the liquid flow path 32. Furthermore, the fluid supplied to the flow path P1 passes through the flow path P1 and is discharged (more specifically, ejected) to the outside from the outlet P1b formed at the tip of the tip 423. In this way, by discharging (more specifically, ejecting) the fluid from the outlet P1b to the outside, for example, by contacting at least one of the teeth and gums in the oral cavity, oral cleaning can be performed.

[0110] Furthermore, as the fluid expelled (more specifically, sprayed) into the oral cavity, water can be used, but it is not limited to water; various liquids can be used. For example, a cleaning solution containing a cleaning agent mixed with water can be used.

[0111] Furthermore, in the oral cleaning device 100 of this embodiment, as described above, the structure does not allow fluid to be continuously discharged from the outlet P1b, but rather allows fluid to be discharged intermittently from the outlet P1b. In this case, the pulse number can be, for example, 8.3 Hz to 50 Hz, more preferably 10 Hz to 30 Hz.

[0112] In this embodiment, the cleaning effect in the oral cavity can be further improved. Specifically, the nozzle 4 is configured such that a fluid (e.g., liquid such as water or gas such as air) with a pressure of 1 MPa or more and 4 MPa is introduced into the flow path P1 from the inlet P1a and discharged from the outlet P1b with a discharge load of 0.19 N or more and 0.38 N or less.

[0113] That is, such as Figure 14 As shown, compared with the case of using conventional nozzles, the pressure introduced into the flow path P1 is greater, but the discharge load of the fluid discharged from the outlet P1b is smaller. Figure 14 This is a graph showing the relationship between the pressure inside the nozzle of the nozzle 4 in this embodiment and the nozzle of the comparative example (i.e., the conventional nozzle) and the load of the discharged water volume. Furthermore, the conventional nozzle used is the nozzle disclosed in the aforementioned prior art documents.

[0114] exist Figure 14 In the diagram, the area indicated by the dashed quadrilateral represents the range of pressure and water discharge load inside the nozzle when using a conventional nozzle, while the area indicated by the solid quadrilateral represents the range of pressure and water discharge load inside the nozzle when using the nozzle 4 of this embodiment.

[0115] And, according to Figure 14 As can be seen, when using nozzle 4 of this embodiment, the pressure introduced into the flow path P1 is greater than that when using a conventional nozzle, and the discharge load of the fluid discharged from the outlet P1b is smaller. Furthermore, according to the graph of solid and dashed lines, when the pressure inside the nozzle is set to the same level, when using nozzle 4 of this embodiment, the discharge load of the fluid discharged from the outlet P1b is smaller than that when using a conventional nozzle.

[0116] Figure 13 This diagram schematically illustrates an example of a method for measuring the pressure inside nozzle 4. In this embodiment, as... Figure 13 As shown, a pressure gauge 4A1 is fixed to the upstream side of the flow path P1 using a connecting fixture 4A2. The pressure gauge 4A1 is used to measure the fluid pressure, thereby obtaining the pressure inside the nozzle. The maximum pressure measured by the pressure gauge 4A1 is then taken as the pressure inside the nozzle. On the other hand, the discharge load of the fluid discharged from the outlet P1b is measured by placing a load sensor 1 mm to 1 cm away from the nozzle tip and bringing the fluid into contact with the surface of the load sensor. The maximum load measured at this time is then taken as the discharge load of the fluid discharged from the outlet P1b.

[0117] Then, experiments were conducted to determine the amount of dirt that could be removed using nozzle 4 and a conventional nozzle, respectively. Specifically, the amount of dirt removed was determined by varying the distance from the tip of the nozzle to the dirt surface, using nozzle 4 and a conventional nozzle. Furthermore, in this embodiment, a photograph was taken of the fluid discharged from the nozzle contacting a plate with substitute dirt (i.e., a substance simulating dirt in the oral cavity) for 5 seconds. The photographed image was then binarized and quantified, and the value obtained from the quantified image was used as the amount of dirt removed.

[0118] Figure 15 This is a graph showing the relationship between the distance from the tip of nozzle 4 in the embodiment and the nozzle in the comparative example to the dirt surface and the amount of dirt removed. Figure 15 The calculation results for dirt removal are shown when the distance from the nozzle tip to the dirt surface is set to 1 mm, 5 mm, 10 mm, and 15 mm using various nozzles. Figure 15 In the graph, the broken line connecting the black quadrilaterals is a graph showing the relationship between the distance from the nozzle tip to the dirt surface and the amount of dirt removed when using a conventional nozzle. Furthermore, the broken line connecting the black circles is a graph showing the relationship between the distance from the nozzle tip to the dirt surface and the amount of dirt removed when using nozzle 4.

[0119] according to Figure 15 As can be seen from the graph, regardless of the distance from the tip of the nozzle to the dirt surface, the amount of dirt removed by using the nozzle 4 of this embodiment is greater than that by using the conventional nozzle.

[0120] Furthermore, when using the nozzle 4 of this embodiment, the flow rate of fluid discharged per minute is approximately 70 mL to 150 mL. On the other hand, when using a conventional nozzle, the flow rate of fluid discharged per minute is approximately 150 mL to 250 mL.

[0121] Therefore, if we express the relationship between the flow rate of fluid discharged in 1 minute and the amount of dirt removed, then it becomes... Figure 16 The diagram shown. Figure 16 This is a graph showing the relationship between the discharge flow rate and the amount of dirt removed from nozzle 4 in the embodiment and the nozzle in the comparative example. Figure 16 In the diagram, the area indicated by the dashed quadrilateral represents the range of flow rate and dirt removal amount when using a conventional nozzle, while the area indicated by the solid quadrilateral represents the range of flow rate and dirt removal amount when using the nozzle 4 of this embodiment.

[0122] Moreover, by Figure 16 It can be seen that, compared with the use of conventional nozzles, the nozzle 4 of this embodiment can remove more dirt with less flow.

[0123] Thus, the inventors conducted repeated and in-depth research and found that if the pressure of the fluid inside the nozzle is 1 MPa or more and 4 MPa or less, and it is discharged with a discharge load of 0.19 N or more and 0.38 N or less, a greater amount of dirt can be removed with a smaller flow rate.

[0124] Furthermore, based on this understanding, by setting a structure in the nozzle 4 to reduce the pressure loss of the fluid inside to between 1 MPa and 4 MPa, the fluid can be discharged with a gentle water flow and a smaller volume of water, thereby further improving the cleaning effect in the oral cavity.

[0125] Specifically, if Figure 11 and Figure 12 As shown, flow path P1 has an inlet flow path P12 (i.e., an example of the first flow path), which is continuously arranged with the connecting flow path P11 and is introduced into the flow path P11. Figure 11 This is a diagram showing an example of the nozzle 4 in the embodiment, which is a longitudinal sectional view obtained by cutting along the plane along the flow path axis C1. Figure 12 This diagram illustrates the configuration relationship of the first narrowing flow path P13 and the widening flow path P14 in an example of the nozzle 4 of the embodiment. Furthermore, the flow path P1 includes a first narrowing flow path P13 (more specifically, a first diameter-reducing flow path, here a throttling section), which is continuously disposed downstream of the inlet flow path P12 (i.e., an example of the first flow path), and its cross-sectional area is smaller than that of the inlet flow path P12 (i.e., an example of the first flow path). The flow path P1 also includes: a widening flow path P14 (more specifically, a diameter-reducing flow path, here a compression chamber), which is continuously disposed downstream of the first narrowing flow path P13, and its cross-sectional area is larger than that of the first narrowing flow path P13; and a second narrowing flow path P15 (more specifically, a second diameter-reducing flow path, here a discharge flow path), which is continuously disposed downstream of the widening flow path P14, and its cross-sectional area is smaller than that of the widening flow path P14. In this embodiment, the flow path axis C1 (refer to...) will be used. Figure 17 When the orthogonal plane cuts through each part, the area of ​​the flow path cross section formed is set as the flow path cross section area of ​​the inlet flow path P12 (i.e., an example of the first flow path), the flow path cross section area of ​​the first shrinking flow path P13, the flow path cross section area of ​​the enlarging flow path P14, and the flow path cross section area of ​​the second shrinking flow path P15.

[0126] Furthermore, in this embodiment, the first narrowing flow path P13 is a small orifice located midway through the flow path P1, enabling liquid jetting, and functions as a throttling section that creates a pressure difference between the liquid before and after passing through the first narrowing flow path P13. Additionally, the widening flow path P14 functions as a compression chamber that compresses the fluid (e.g., liquid or gas) supplied inside. Furthermore, the second narrowing flow path P15 communicates with the outlet P1b, functioning as a discharge flow path that allows liquid to be discharged from the outlet P1b. Thus, in this embodiment, the narrowing flow path (more specifically, the throttling section) includes: a first narrowing flow path P13, which is continuously disposed downstream of the inlet flow path P12 (i.e., an example of the first flow path) of the flow path P1, and has a flow path cross-sectional area smaller than that of the inlet flow path P12 (i.e., an example of the first flow path); and a second narrowing flow path P15, which is located downstream of the first narrowing flow path P13. Furthermore, the first narrowing flow path P13 and the second narrowing flow path P15 are continuously disposed via an enlarging flow path P14 with a flow path cross-sectional area larger than that of the first narrowing flow path P13 and the second narrowing flow path P15.

[0127] Furthermore, by designing the structure in this way, the internal pressure loss of the nozzle 4 can be reduced more efficiently, allowing fluids (such as liquids like water or gases like air) to be discharged more reliably from the outlet P1b with a discharge load of more than 0.19N and less than 0.38N.

[0128] Furthermore, by setting a first narrowing flow path P13 in the middle of the flow path P1, the gas (e.g., air) introduced into the flow path P1 can diffuse as it is introduced from the first narrowing flow path P13 into the widening flow path P14. As a result, the liquid and gas can be pressurized, dissolved, and mixed more efficiently, and the generation of droplets or microbubbles (more specifically, bubbles around several hundred μm) and cavitation bubbles can be increased.

[0129] Thus, increasing the generation of droplets, microbubbles, cavitation bubbles, etc., increases the shear force, pressure fluctuations, and vibrations generated when the fluid discharged from the outlet P1b comes into contact with the cleaning surfaces such as tooth surfaces. This further increases the force that peels away dirt adhering to the tooth surfaces. As a result, the increased cleaning force further improves the cleaning effect in the oral cavity.

[0130] In this embodiment, the connecting flow path P11 is a flow path formed by dividing the inner wall surface 411 of the connecting part 41, and the upstream end of the connecting flow path P11 is called the inlet P1a.

[0131] Furthermore, in this embodiment, the housing body 42 includes a first flow path structure portion 424, which is continuously disposed upstream of the connecting portion 41 and has an inlet flow path P12 (i.e., an example of the first flow path) formed inside. Additionally, the housing body 42 includes a second flow path structure portion 425, which is continuously disposed upstream of the first flow path structure portion 424 and has a first narrowing flow path P13 formed inside. Moreover, the housing body 42 includes a third flow path structure portion 426, which is continuously disposed upstream of the second flow path structure portion 425 and has an enlarging flow path P14 formed inside. Finally, the housing body 42 includes a fourth flow path structure portion 427, which is continuously disposed upstream of the third flow path structure portion 426 and has a second narrowing flow path P15 formed inside.

[0132] Here, the inlet flow path P12 (i.e., an example of the first flow path) is a flow path formed by dividing the first inner wall surface 4241 of the first flow path constituting part 424. The upstream end of the first inner wall surface 4241 and the downstream end of the inner wall surface 411 of the connecting part 41 are continuously provided. Furthermore, in this embodiment, an upstream inclined surface 42411 that slopes inward toward the downstream is formed in the middle of the first inner wall surface 4241, and the inlet flow path P12 (i.e., an example of the first flow path) is formed such that the cross-sectional area of ​​the flow path on the downstream side is smaller than the cross-sectional area of ​​the flow path on the upstream side. That is, the inlet flow path P12 (i.e., an example of the first flow path) is formed into a shape having a large-diameter flow path on the upstream side, a small-diameter flow path on the downstream side, and a narrow-diameter flow path connecting the large-diameter flow path and the small-diameter flow path. In addition, in this embodiment, the flow path P1 is formed such that the cross-sectional shape when cut by a plane orthogonal to the flow path axis C1 is approximately circular, and the diameter d1 of the small-diameter flow path leading to the flow path P12 (i.e., an example of the first flow path) is approximately 2.9 mm.

[0133] Furthermore, the first narrowing flow path P13 is a flow path formed by dividing the second inner wall surface 4251 of the second flow path structure 425, and the upstream end of the second inner wall surface 4251 is continuously provided with the downstream end of the first inner wall surface 4241. In this embodiment, the downstream end of the first inner wall surface 4241 becomes a downstream inclined surface 42412 that slopes inward as it moves downstream. Thus, the inlet flow path P12 (i.e., an example of the first flow path) is connected to the first narrowing flow path P13 while the flow path cross-sectional area gradually decreases (more specifically, the diameter gradually narrows). Alternatively, a curved surface may be provided instead of the downstream inclined surface 42412. In this case, it is preferable that the downstream inclined surface 42412 and the curved surface are provided continuously with the upstream end of the second inner wall surface 4251 in a smooth and continuous manner.

[0134] Furthermore, in this embodiment, the first narrowing flow path P13 is formed to have approximately the same cross-sectional area (more specifically, approximately the same diameter) from the upstream side to the downstream side. In this embodiment, the diameter d2 of the first narrowing flow path P13 is approximately 1.0 mm. It should be noted that the ratio of the opening area of ​​the first narrowing flow path P13 to the small-diameter flow path of the inlet flow path P12 (i.e., an example of the first flow path) is preferably 1:1.5 to 3.

[0135] Furthermore, the overall length L of the nozzle housing 40 along the flow path axis C1 is preferably about 90 mm to about 120 mm. Moreover, in this embodiment, with the overall length L set to the range of about 90 mm to about 120 mm, the length L2 of the second flow path component 425 along the flow path axis C1 is set to about 3.0 mm.

[0136] The enlarged flow path P14 is a flow path formed by dividing the third inner wall surface 4261 of the third flow path structure 426. The upstream end of the third inner wall surface 4261 is continuously provided with the downstream end of the second inner wall surface 4251. In this embodiment, the upstream end of the third inner wall surface 4261 becomes an upstream vertical surface 42611 perpendicular to the flow path axis C1. In this embodiment, the diameter d3 of the enlarged flow path P14 is approximately 2.9 mm. Furthermore, with the overall length L set to a range of approximately 90 mm to approximately 120 mm, the length L3 of the third flow path structure 426 along the flow path axis C1 is set to approximately 7.5 mm.

[0137] The second narrowing flow path P15 is a flow path formed by dividing the fourth inner wall surface 4271 of the fourth flow path structure 427, and the downstream end of the second narrowing flow path P15 becomes the discharge port P1b. Furthermore, the upstream end of the fourth inner wall surface 4271 and the downstream end of the third inner wall surface 4261 are continuously provided. In this embodiment, the downstream end of the third inner wall surface 4261 becomes a downstream vertical surface 42612 perpendicular to the flow path axis C1. In this embodiment, the diameter d4 of the upstream end of the second narrowing flow path P15 is approximately 0.38 mm. Furthermore, the opening area of ​​the upstream end of the second narrowing flow path P15 is preferably approximately 0.03 mm². 2 ~ Approximately 0.196mm 2The range is specified. Furthermore, it is preferable that the ratio of the diameter d1 of the small-diameter flow path of the inlet flow path P12 (i.e., an example of the first flow path) to the diameter d4 of the upstream end of the second narrowing flow path P15 is approximately 0.05 to approximately 0.25. Additionally, the ratio of the opening area of ​​the upstream end of the second narrowing flow path P15 to the opening area of ​​the small-diameter flow path of the inlet flow path P12 (i.e., an example of the first flow path) is preferably 1:1 to 15. This allows for pressure loss within the nozzle 4, enabling the fluid (e.g., liquid such as water or gas such as air) to be discharged from the outlet P1b with a discharge load of 0.19 N or more and 0.38 N or less.

[0138] Furthermore, in this embodiment, with the overall length L set to a range of approximately 90 mm to approximately 120 mm, the length L4 of the fourth flow path component 427 along the flow path axis C1 is set to approximately 8.5 mm.

[0139] In this embodiment, the connecting flow path P11, the introducing flow path P12 (i.e., an example of the first flow path), and the first narrowing flow path P13 are arranged in a straight line. That is, the flow path P1 is formed in a straight line from the upstream end of the connecting flow path P11 to the downstream end of the first narrowing flow path P13. Thus, in this embodiment, the introducing flow path P12 (i.e., an example of the first flow path) and the first narrowing flow path P13 are formed in the rod portion 421.

[0140] In addition, in this embodiment, the enlarged flow path P14 is formed to bend from the upstream side to the downstream side, and the enlarged flow path P14 is formed in the bend 422.

[0141] Furthermore, the second shrinkage flow path P15 is formed in a straight line that intersects the direction of the inlet flow path P12 (i.e., an example of the first flow path) and the first shrinkage flow path P13, and the second shrinkage flow path P15 is formed at the top end 423.

[0142] Furthermore, in this embodiment, the shape of the second narrowing flow path P15 is a cone with a wider downstream side. This allows the fluid compressed in the widening flow path P14 and introduced into the second narrowing flow path P15 to be discharged from the outlet P1b along the wall that divides the second narrowing flow path P15 (more specifically, the fourth inner wall surface 4271). That is, the fluid flows along the cone-shaped portion, forming a further expanded flow within the second narrowing flow path P15. Specifically, by generating a wall adhesion effect, the fluid vibrates in a manner that moves along the wall, maintaining the discharge velocity and expanding the cleaning area.

[0143] Furthermore, if the fluid is not stripped from the fourth inner wall surface 4271, the amount of microbubbles generated can be further increased.

[0144] However, if the cone angle θ of the second narrowing flow path P15 is too large, the fluid cannot be discharged from the outlet P1b while running along the wall surface that divides the second narrowing flow path P15 (more specifically, the fourth inner wall surface 4271). In such a case, the fluid is discharged only from the central portion of the outlet P1b, and the fluid with the core comes into contact with the cleaning surface such as the tooth surface. Thus, the fluid only comes into contact with a narrow area, reducing cleaning efficiency or increasing surface pressure, resulting in a lower sensory evaluation during use.

[0145] Therefore, it is preferable to set an appropriate nozzle cone angle so that the fluid flows along the cone shape, which can maintain cleaning and expand the cleaning area.

[0146] Therefore, in this embodiment, the cone angle θ of the second narrowing flow path P15 is 0 degrees or more and 5 degrees or less. Specifically, the cone angle θ of the wall surface (more specifically, the fourth inner wall surface 4271) that divides the second narrowing flow path P15 is 3 degrees. This allows the fluid to be discharged from the outlet P1b more reliably while flowing along the wall surface (more specifically, the fourth inner wall surface 4271) that divides the second narrowing flow path P15. This also more reliably prevents the fluid from being discharged only from the center portion of the outlet P1b, thus preventing the fluid with a core from contacting the cleaning surface such as the tooth surface. As a result, it more reliably prevents situations where the fluid only contacts a narrow area, leading to reduced cleaning efficiency, or where the surface pressure increases, resulting in lower sensory evaluation during use.

[0147] Thus, in this embodiment, by setting the shape of the second narrowing flow path P15 to a cone shape with a wider downstream width and a cone angle θ of 0 degrees or more and 5 degrees or less, it is possible to allow the fluid to contact a larger area of ​​the cleaning surface, such as the tooth surface, while maintaining the cleaning force (i.e., an example of dirt removal efficiency). In other words, it is possible to allow a fluid with high cleaning force (i.e., an example of dirt removal efficiency) to contact a larger area. In this way, oral cavity cleaning can be performed more effectively and efficiently.

[0148] Furthermore, this embodiment also includes the case where the cone angle θ of the second narrowing flow path P15 is 0 degrees. In this case, the second narrowing flow path P15 has the same cross-sectional shape from the upstream side to the downstream side, and the flow path cross-sectional area (more specifically, cross-sectional area) at any part from the upstream side to the downstream side is the same value (more specifically, the same diameter). Specifically, the first section line 42711 and the second section line 42712 of the fourth flow path component 427 extend parallel to each other. Here, the first section line 42711 and the second section line 42712 refer to the intersection line of the cutting plane (i.e., the cutting plane) with the fourth inner wall surface 4271 when the fourth flow path component 427 is cut along the flow path axis C1.

[0149] Thus, in this embodiment, the second narrowing flow path P15, with a cone angle θ of 0 degrees, is also included in the cone with a wider width on the downstream side.

[0150] Furthermore, in this embodiment, the nozzle housing 40 is formed using a resin (e.g., amorphous resin or polypropylene). Thus, in this embodiment, the second flow path structure portion 425 is formed of the same material as the flow path structure portions 424 and 426.

[0151] In this way, the formation of unexpected steps and gaps can be more reliably suppressed at least one of the connections between the second flow path structure 425 and the first flow path structure 424, and between the second flow path structure 425 and the third flow path structure 426 (more specifically, the connections between adjacent inner wall surfaces). As a result, the generation of useless pressure loss can be more reliably suppressed, and the reduction of cleaning force can be minimized.

[0152] Furthermore, the nozzle housing 40 is integrally formed using resin. Therefore, in this embodiment, the second flow path structure portion 425 is integrally formed with at least one of the first flow path structure portion 424 and the third flow path structure portion 426.

[0153] In this way, it is not necessary to insert other components into the flow path P1 to form the first narrowed flow path P13, thus making it easier to obtain a nozzle 4 with the first narrowed flow path P13. Furthermore, when using other components to form the first narrowed flow path P13, tiny gaps may form within the flow path P1, resulting in useless pressure loss and reduced cleaning force. However, if the second flow path structure 425 is integrally formed with at least one of the first flow path structure 424 and the third flow path structure 426, the formation of tiny gaps within the flow path P1 can be more reliably suppressed, thereby more reliably suppressing the generation of useless pressure loss. As a result, the reduction in cleaning force can be significantly reduced.

[0154] Furthermore, when the first narrowing flow path P13 is formed using other components, if a metal component is used, at least one of rust and corrosion may occur due to the fluid flowing inside. If a cleaning agent is used, black liquid resulting from an oxide coating or the like may also be discharged from the outlet P1b. In contrast, when the first narrowing flow path P13 (i.e., the flow path included in the second flow path structure 425) is formed from resin as in this embodiment, rust or corrosion due to the fluid flowing inside can be suppressed. Additionally, if a chemically resistant resin is used to form the nozzle housing 40, the discharge of black liquid from the outlet P1b can be suppressed, and damage to the appearance quality can also be prevented.

[0155] Furthermore, if resin is used instead of metal to form the first narrowing flow path P13, the nozzle 4 can be made lighter and the manufacturing cost can be reduced.

[0156] Furthermore, using resin to form the nozzle housing 40 increases the freedom of shape and manufacturing process. Additionally, resin is easier to color, thus enabling the adaptation to various designs.

[0157] Furthermore, if the nozzle housing 40 is manufactured by resin molding, it also has the advantage of easily obtaining dimensional accuracy.

[0158] Furthermore, if the second flow path structure 425 is integrally formed with at least one of the first flow path structure 424 and the third flow path structure 426, the strength of the nozzle housing 40 can be further improved. As a result, even when fluid is introduced into the flow path P1 from the inlet P1a at a high pressure of 1 MPa or more and 4 MPa or less, deformation and breakage of the nozzle housing 40 can be suppressed more reliably.

[0159] In particular, it can suppress the first narrowing flow path P13 from moving due to fluid, as is the case when other components are used to form the first narrowing flow path P13, thus further improving the strength of the nozzle housing 40.

[0160] As explained above, in this embodiment, the nozzle housing 40 is integrally formed using resin. Thus, the nozzle housing 40 is formed using a single raw material (in this case, resin).

[0161] Furthermore, a flow path P1 is formed inside the nozzle housing 40. In this embodiment, in order to make the internal pressure and discharge load have the aforementioned relationship, the flow path P1 formed inside the nozzle housing 40 has a complex shape.

[0162] Thus, it is preferable to be able to manufacture nozzle housing 40 with complex flow path shape more easily.

[0163] Therefore, in this embodiment, a structure is formed that makes it easier to manufacture a nozzle housing 40 with a complex flow path shape.

[0164] Specifically, if Figure 18 As shown, the nozzle housing 40 includes: a first forming member 5 having a first recess 512 forming part of the flow path P1; and a second forming member 6 having a second recess 612 forming part of the flow path P1 and engaging with the first forming member 5. Furthermore, as... Figure 20 As shown, the mating surface 81 between the first forming member 5 and the second forming member 6 extends along the flow path axis C1 of the flow path P1. Figure 18The figure is an example of a method for manufacturing the nozzle 4, and is a cross-sectional view showing the state in which the first forming member 5 and the second forming member 6 are prepared. Figure 19 This is a diagram illustrating an example of the manufacturing method of the nozzle 4, and a cross-sectional view showing the state in which the first forming member 5 and the second forming member 6 are stacked together. Figure 20 The diagram shows an example of a method for manufacturing nozzle 4, and is a cross-sectional view showing the state in which a joining member is formed in an inflow space 7 formed by overlapping first forming member 5 and second forming member 6 using a mold.

[0165] Thus, if the first forming member 5 and the second forming member 6 are joined to form a flow path P1, and the joining surface 81 is aligned with the flow path axis C1 of the flow path P1, then by stacking and joining the first forming member 5 and the second forming member 6, a flow path P1 can be formed inside the nozzle housing 40. Therefore, it is easier to obtain a nozzle housing 40 with a complex flow path shape.

[0166] In this embodiment, the first forming member 5 has a semi-circular first wall portion 51, and a semi-circular first recess 512 is formed on the diameter portion of the semi-circular first wall portion 51. Furthermore, the surface that is connected to the curved surface that divides the semi-circular first recess 512 is called the first abutting surface 511.

[0167] Similarly, the second forming member 6 has a semi-circular second wall portion 61, and a semi-circular second recess 612 is formed in the diameter portion of the semi-circular second wall portion 61. Moreover, the surface that is connected to the curved surface that divides the semi-circular second recess 612 becomes the second abutment surface 611.

[0168] Thus, in this embodiment, a first abutting surface 511 is formed on the first forming member 5, and a second abutting surface 611 is formed on the second forming member 6 that abuts against the first abutting surface 511.

[0169] Furthermore, in this embodiment, a recess is formed at the center of the first abutting surface 511 as a first positioning portion 5111. And a protrusion is formed at the center of the second abutting surface 611 as a second positioning portion 6111 that engages with the first positioning portion 5111 to position the first forming member 5 and the second forming member 6.

[0170] Therefore, when the first forming member 5 and the second forming member 6 are joined to form the joint surface 81, misalignment between the first forming member 5 and the second forming member 6 can be more reliably suppressed.

[0171] Furthermore, in this embodiment, a first notch 5112 is formed on the outer side of the first abutting surface 511 in the first wall portion 51, and a second notch 6112 is formed on the outer side of the second abutting surface 611 in the second wall portion 61.

[0172] Therefore, as Figure 19 As shown, when the first recess 512 and the second recess 612 are facing each other, and the first positioning part 5111 and the second positioning part 6111 are engaged and the first abutting surface 511 and the second abutting surface 611 are in contact, an inflow space 7, which serves as a secondary flow path, is formed.

[0173] Furthermore, a joining member 8 is formed by allowing resin to flow into the inflow space 7 and fixing it. As a result, a joining surface 81 extending along the flow path axis C1 of the flow path P1 is formed.

[0174] In this embodiment, the first forming member 5 and the second forming member 6 are joined by thermal fusion. That is, the joint surface 81 between the first forming member 5 and the second forming member 6 becomes the thermal fusion portion 82. As a result, compared with the case where the joint surface 81 is formed by vibration welding, the joint strength can be improved, and the strength of the nozzle housing 40 can be further improved.

[0175] It should be noted that the first forming component 5 and the second forming component 6 do not need to be joined by heat fusion. The first forming component 5 and the second forming component 6 can be joined by various methods such as vibration welding.

[0176] Moreover, the nozzle housing 40 with such a structure can be formed, for example, by the following method.

[0177] First, such as Figure 18 As shown, a first molding member 5 and a second molding member 6 are formed. The first molding member 5 and the second molding member 6 may be, for example, resin molded articles formed by flowing resin into a mold.

[0178] Next, as Figure 19 As shown, with the first recess 512 and the second recess 612 facing each other, the first positioning part 5111 and the second positioning part 6111 are engaged, and the first abutting surface 511 and the second abutting surface 611 abut against each other. As a result, the inflow space 7 is formed by the first notch 5112 and the second notch 6112.

[0179] Then, as Figure 20As shown, using the first mold 91 and the second mold 92, resin flows into the inflow space 7 from the resin gate 93 formed in the first mold 91 and is fixed therein. Furthermore, the resin gate 93 can be formed in the second mold 92, or in both the first mold 91 and the second mold 92. Moreover, by flowing in at a high temperature that prevents resin deterioration, the first molding part 5 and the second molding part 6 are more reliably heat-fused together by the joining member 8.

[0180] Thus, a joint surface 81 between the first forming member 5 and the second forming member 6 is formed in such a way that it extends along the flow path axis C1 of the flow path P1, thereby forming the nozzle housing 40.

[0181] In this embodiment, resin is injected toward the inner side of the inflow space 7. At this time, to facilitate the application of holding pressure, the shape of the inflow space 7 is designed to be narrower in width and deeper in depth. Specifically, the depth d5 ​​of the inflow space 7 (more specifically, Figure 17 The length in the width direction of the space is approximately 1.27 mm, and the width W1 of the inflow space 7 (more specifically, Figure 17 The length in the vertical direction is referenced. Figure 23 The value is approximately 1.0 mm. Figure 17 This diagram illustrates an example of the nozzle 4 in the embodiment, and is a cross-sectional view obtained by cutting with a plane orthogonal to the flow path axis C1. Furthermore, in this embodiment, the widths of the first abutment surface 511 and the second abutment surface 611 (more specifically, Figure 17 The length in the width direction of the first positioning part 5111 and the second positioning part 6111 (more specifically, the length in the width direction of the first positioning part 5111 and the second positioning part 6111) is approximately 0.9 mm. Figure 17 The length in the width direction is approximately 0.3 mm. Furthermore, the height and depth (more specifically, the length in the width direction of the first positioning part 5111 and the second positioning part 6111) are approximately 0.3 mm. Figure 17 The length in the vertical direction is also approximately 0.3 mm.

[0182] Furthermore, when the first forming member 5 and the second forming member 6 are joined by heat fusion as in this embodiment, it is preferable that the nozzle housing 40 has an outer diameter cross-sectional area of ​​1.5 cm². 2 The following resin molded article, and the width W1 of the inflow space 7 (refer to) Figure 23 The ratio of the outer diameter of the nozzle housing 40 to the outer diameter of the nozzle housing 40 is 0.25 to 0.5.

[0183] Furthermore, the resin used to form the bonding member 8 is preferably an amorphous resin, polypropylene, or the like. Moreover, a resin with a melt flow rate (hereinafter referred to as "MFR") of 7 or higher is preferred.

[0184] In this embodiment, the flow path P1 formed when the first forming member 5 and the second forming member 6 are joined by the joining member 8 has a first narrowing flow path P13.

[0185] Specifically, a first reduced flow path P13 with a small flow path cross-sectional area is formed by providing a protrusion in the recess of at least one of the first forming member 5 and the second forming member 6.

[0186] In this embodiment, by forming a first protrusion 513 within the first recess 512, a first narrowed flow path P13 with a small flow path cross-sectional area is formed. Furthermore, in this embodiment, as... Figure 21 As shown, a through hole is formed in the first protrusion 513, which becomes the first narrowed flow path P13. Figure 21 This is a diagram showing an example of the nozzle 4 in the embodiment. It is a cross-sectional view obtained by cutting the portion where the first narrowing flow path P13 exists with a plane orthogonal to the flow path axis C1.

[0187] Thus, if the nozzle housing 40 is formed using the method described above, it is easier to manufacture a nozzle housing 40 with a flow path P1 having a complex shape formed inside.

[0188] Furthermore, in this embodiment, the top end side of the housing body 42 downstream of the connecting portion 41 of the nozzle housing 40 is divided into two. In this case, it is preferable that at least the root side (connecting portion 41 side) of the housing body 42 is not divided. Specifically, as... Figure 10 As shown, the portion from the top 423 to the part forming the first narrowed flow path P13 is divided into two. Figure 10 This is a side view showing an example of nozzle 4 in an embodiment.

[0189] In addition, such as Figure 22 As shown, the nozzle housing 40 may also have a thick-walled portion 40a and a thin-walled portion 40b. Figure 22 This is a diagram showing a first modified example of the nozzle 4 according to the embodiment. It is a cross-sectional view obtained by cutting with a plane orthogonal to the flow path axis C1. At this time, if a joint surface 81 is formed in the thick-walled portion 40a, the joint area of ​​the joint surface 81 extending along the flow path axis C1 of the flow path P1 can be further enlarged, so that the first forming member 5 and the second forming member 6 can be joined more reliably.

[0190] exist Figure 22 In this case, the inflow space 7 is formed in the thick-walled portion 40a. This ensures more reliably the depth d5 ​​of the inflow space 7 (refer to...). Figure 23 Therefore, it is easy to apply holding pressure, and the first forming part 5 and the second forming part 6 can be joined more reliably by the joining member 8.

[0191] In addition, such as Figure 23 As shown, by making the cross-sectional shape of the flow path P1 elongated in one direction, the nozzle housing 40 can also have a thick-walled portion 40a and a thin-walled portion 40b. Figure 23 This is a diagram showing a second modified example of the nozzle 4 in the embodiment. It is a cross-sectional view obtained by cutting with a plane orthogonal to the flow path axis.

[0192] exist Figure 23 In the example, the cross-sectional shape of the flow path P1 is made into an ellipse with a major axis a and a minor axis b. Furthermore, an inflow space 7 is formed in the thick-walled portion 40a along the minor axis b in the depth direction.

[0193] This avoids making the nozzle housing 40 appear larger and allows for more reliable assurance of the depth d5 ​​of the inflow space 7.

[0194] However, when the pipe cross-section is non-circular, pipe friction increases proportionally to the circumference. Therefore, the pressure loss caused by the pipe is proportional to the pipe cross-section (circumference / flow path cross-sectional area). Thus, the ratio of the major axis a to the minor axis b (a / b) is preferably 1 to 2. Figure 23 In the figure, the major axis a is set to approximately 3.4 mm, and the minor axis b is set to approximately 2.5 mm.

[0195] In addition, such as Figure 24 As shown, a first protrusion 513 may also be formed in the first recess 512, and a second protrusion 613 may be formed in the second recess 612. Figure 24 This diagram schematically illustrates an example of a nozzle that can be manufactured using a method for manufacturing nozzle 4. In this way, the shape of the flow path P1 can be made complex without complicating the external shape of the nozzle housing 40.

[0196] In addition, regarding the appearance of the nozzle housing 40 and the shape of the flow path P1, such as Figure 25 As shown, it can also be a curved shape, such as... Figure 26 As shown, it can also be bent into a 90-degree shape. Figure 25 This is a schematic diagram illustrating an example of the appearance and flow path shape of a nozzle 4 that can be manufactured by an example of a nozzle 4 manufacturing method. Figure 26 This diagram schematically illustrates the external shape of a nozzle and another example of the flow path shape that can be manufactured using one method of manufacturing nozzle 4. Thus, the external appearance of the nozzle housing 40 and the shape of the flow path P1 can be set to various shapes.

[0197] Furthermore, regarding the cross-sectional shape of the nozzle housing 40 and the cross-sectional shape of the flow path P1, such as Figure 27 As shown, it can also be set as a shape composed of a combination of arcs and straight lines, such as... Figure 28 As shown, it can also be set to a quadrilateral shape. Figure 27 This is a schematic diagram illustrating an example of the appearance and cross-sectional shape of the flow path of a nozzle 4 that can be manufactured by an example of a nozzle 4 manufacturing method. Figure 28 This is a schematic diagram illustrating another example of the appearance and cross-sectional shape of the flow path of a nozzle 4 that can be manufactured by one example of the manufacturing method of nozzle 4.

[0198] The cross-sectional shape of the nozzle housing 40 and the cross-sectional shape of the flow path P1 can also be set to various shapes, such as triangular shapes and polygonal shapes of pentagons or more.

[0199] Alternatively, it can be configured as a nozzle 4 having multiple discharge outlets P1b and a first narrowing flow path P13.

[0200] Furthermore, the structure of the oral cleaning device 100 is not limited to the structure shown in the above embodiment, and can be configured in various ways.

[0201] For example, it can be set to Figures 29-31 The oral cleaning device 100 shown. Figure 29 This is a perspective view of the oral cleaning device 100 of the first modified embodiment, viewed from one direction. Figure 30 This is a perspective view of the oral cleaning device 100 of the first modified embodiment, viewed from another direction. Figure 31 This is a perspective view showing the gripping part 10 and the nozzle 4 in the first modified embodiment. Figures 29-31 The oral cleaning device 100 shown includes: a device body 3 having a housing 31 (i.e., an example of a shell); a handle 10 (i.e., an example of a handle) that a user or the like can hold by hand; and a nozzle 4 (more specifically, an oral cleaning device nozzle) mounted on the handle 10. This oral cleaning device 100 also discharges (more specifically, sprays out) a fluid (e.g., liquid) such as water from the outlet P1b of the nozzle 4, causing the fluid stream to contact the teeth, gums, etc., inside the oral cavity for cleaning.

[0202] The main body 3 of the device includes the aforementioned shell 31 (i.e., an example of the outer shell) and a liquid storage tank 2 (i.e., an example of the liquid storage section) capable of storing liquid, and the main body 3 is generally rectangular. The shell 31 (i.e., an example of the outer shell) and the liquid storage tank 2 can be formed using materials such as synthetic resin, but are not limited to this, and can be formed using various materials.

[0203] Additionally, a pump 33 is built into the housing 31 (i.e., an example of the outer casing), and the liquid storage tank 2 and the hose 34A are connected via the pump 33. This pump 33 is positioned in the liquid flow path 32 and has the function of drawing in the liquid stored in the liquid storage tank 2 and discharging it from the nozzle 4. Therefore, in Figures 29-31In the oral cleaning device 100 shown, liquid stored in the reservoir 2 is supplied to the hose 34A via pump 33. Figures 29-31 The oral cleaning device 100 shown also uses the pump 33 described in the above embodiment. Additionally, in Figures 29-31 The oral cleaning device 100 shown also uses the pump drive mechanism 34 described in the above embodiment. At this time, a pump drive mechanism 34 equipped with an auxiliary mechanism 346 or a pump drive mechanism 34 without an auxiliary mechanism 346 can be used. However, there is no particular limitation on the type of pump; similar to the above embodiment, various types of pumps can be used.

[0204] Furthermore, the main body 3 of the device does not need to have a liquid storage tank 2; for example, it can also directly introduce liquids such as tap water from the outside.

[0205] In addition, Figures 29-31 In the oral cleaning device 100 shown, the housing 31 (i.e., an example of the outer casing) is provided with a handle holding part 31a for holding the handle part 10 when the oral cleaning device 100 (more specifically, the device body 3) is not in use, and a hose holding part 31b for winding and holding the hose 34A. Furthermore, inside the housing 31 (i.e., an example of the outer casing), there is a control board or the like, which serves as a control unit for controlling the operation of the pump 33, etc.

[0206] Additionally, wiring 35A and power supply line 36A are connected to housing 31 (i.e., an example of the outer casing), and power for operating pump 33 and the like is supplied from an external power source via power supply line 36A.

[0207] And, as Figure 30 As shown, a power switch 37A for switching the power supply on and off, and hydraulic switches 38aA and 38bA for switching the hydraulic pressure of the liquid discharged (more specifically, ejected) from the nozzle 4 are provided in the housing 31 (i.e., an example of the outer casing). Therefore, in Figures 29-31 In the oral cleaning device 100 shown, when the power is turned on by operating the power switch 37A, the liquid can be discharged (more specifically, sprayed out) from the nozzle 4 with the desired hydraulic pressure by operating the hydraulic switching switches 38aA and 38bA.

[0208] like Figure 29 As shown, the gripping part 10 is connected to the housing 31 (i.e., an example of the outer casing) of the device body 3 via a flexible hose 34A. Furthermore, as... Figure 31 As shown, the gripping part 10 includes a housing 11 forming its outer contour. The housing 11 can be formed, for example, using an insulating synthetic resin material, by joining multiple segments together. Furthermore, a cavity is formed inside the housing 11 formed by joining the segments, and various electrical components are housed within this cavity.

[0209] Furthermore, the grip 10 has an operation switch 10a partially exposed on the surface side. Users can operate the operation switch 10a while holding the grip 10, thereby switching the liquid spraying on and off.

[0210] Furthermore, a nozzle mounting portion 111 is formed in the housing 11 of the holding portion 10 with an upward opening. By inserting and fitting the connecting portion 41 into the nozzle mounting portion 111, the nozzle housing 40 (i.e., an element of the nozzle 4) is detachably mounted to the holding portion 10. Moreover, when the nozzle housing 40 (i.e., an element of the nozzle 4) is mounted to the holding portion 10, the flow path P1 inside the nozzle housing 40 communicates with a flow path (not shown) formed inside the housing 11 and communicating with the hose 34A. At this time, the nozzle 4 is preferably inserted into the nozzle mounting portion 111 in a sealed state, for example, by a gasket.

[0211] As such an oral cleaning device 100, it can also perform the same function and effect as the oral cleaning device 100 shown in the above embodiment.

[0212] Additionally, it can be set to Figure 32 The oral cleaning device 100 shown. Figure 32 This is a schematic diagram illustrating the oral cleaning device 100 of the second modification of the embodiment. Figure 32 The oral cleaning device 100 shown includes a liquid storage tank 2, a device body 3, and a nozzle 4.

[0213] The liquid storage tank 2 is formed as a bottomed cylindrical shape that opens upwards and closes at the lower end. Inside the liquid storage tank 2, a storage section 2a is formed for storing liquid. Furthermore, water can be used as the liquid stored in the storage section 2a, but it is not limited to water; various liquids can be used. For example, a cleaning solution containing a cleaning agent mixed with water can be used.

[0214] Furthermore, the device body 3 is supported on the liquid storage tank 2 in a state that allows it to slide along the vertical direction (i.e., the length direction of the device body 3). At this time, the device body 3 is slidably supported on the liquid storage tank 2 while being disposed at least at its lower end within the storage section 2a.

[0215] Furthermore, by sliding the main body 3 downwards towards the liquid reservoir 2, it is housed within the reservoir 2, allowing for more compact storage when the oral cleaning device 100 is not in use. Additionally, by sliding the main body 3 upwards towards the liquid reservoir 2, it is pulled upwards, allowing more liquid to be supplied to the storage section 2a of the reservoir 2. Furthermore, with the main body 3 pulled upwards towards the liquid reservoir 2, the nozzle 4 is attached to the main body 3, supplying liquid to the storage section 2a of the reservoir 2, thus enabling the use of the oral cleaning device 100. Therefore, in Figure 32 In the oral cleaning device 100 shown, the main body 3 and the liquid storage tank 2 are made into a handle 10 that can be held by hand by the user (i.e., an example of a handle).

[0216] so, Figure 32 The oral cleaning device 100 shown is a telescopic oral cleaning device with the main body 3 supported on the reservoir 2 in a manner that allows it to slide between a stored state and a pulled-out state. That is, when the oral cleaning device 100 is not in use, the nozzle 4 can be detached from the main body 3, and the main body 3 can be pressed into the reservoir 2 for storage. Furthermore, the oral cleaning device 100 can be used by pulling the main body 3 out of the reservoir 2 and attaching the nozzle 4 to the main body 3.

[0217] At this time, it is preferable that the device body 3 is supported on the liquid storage tank 2 in a detachable manner. That is, preferably, the device body 3 can be detached from the liquid storage tank 2 by pulling it upward, or the device body 3 can be installed on the liquid storage tank 2 by pressing it downward while the lower end of the device body 3 is inserted into the liquid storage tank 2. In this way, cleaning can be performed while the liquid storage tank 2 is separated from the device body 3, thus keeping both the liquid storage tank 2 and the device body 3 cleaner.

[0218] Furthermore, the liquid storage tank 2 is made of polypropylene resin or the like so that it can be washed in a dishwasher, and is formed into a transparent or semi-transparent container shape to improve design flexibility. Moreover, the horizontal cross-sectional shape of the liquid storage tank 2 is formed into a perfect circle so that the main body 3 of the device can be rotated relative to it.

[0219] The liquid storage tank 2 has a generally cylindrical body 21 with openings at the top and bottom, and a bottom wall 22 that closes the lower opening of the cylindrical body 21. Furthermore, a liquid supply hole (not shown) is formed on the side of the liquid storage tank 2 (more specifically, the cylindrical body 21) for injecting liquid into the storage section 2a; this liquid supply hole is closed by a liquid supply cap (not shown). Therefore, even when the liquid storage tank 2 is placed horizontally, liquid can be supplied to the storage section 2a within the liquid storage tank 2.

[0220] On the other hand, the device body 3 has a shell 31 that forms the outer contour. The shell 31 is formed into a cylindrical shape with its two ends closed in the vertical direction. Furthermore, the cross-sectional shape of the shell 31 (i.e., an example of the device body 3) is also formed into a perfect circle so that it can rotate relative to the liquid storage tank 2.

[0221] Therefore, in Figure 32In the oral cleaning device 100 shown, the housing 31 includes: a generally circular plate-shaped top wall 311; a generally cylindrical peripheral wall 312 extending downward from the outer periphery of the top wall 311; and a generally circular plate-shaped bottom wall 313, which is provided to block the opening on the lower side of the peripheral wall 312.

[0222] A nozzle mounting portion 3111 is formed on the top wall 311. The nozzle mounting portion 3111 is formed into a hollow strip shape, and a nozzle 4 that can be detachably installed to allow liquid to be discharged (more specifically, sprayed out) from the top.

[0223] In addition, the peripheral wall 312 is provided with a button (not shown) that allows the nozzle 4 to be removed from the housing 31 (i.e., an example of the device body 3), and a power switch (not shown) that allows the oral cleaning device 100 to be started or stopped (i.e., to switch the power supply of the oral cleaning device 100 on or off).

[0224] Furthermore, a pipe mounting portion 3132 for mounting the pipe 5A is formed on the bottom wall 313.

[0225] In addition, Figure 32 In the oral cleaning device 100 shown, the tube 5A is integrally mounted on the tube mounting part 3132. When the device body 3 is slidably mounted on the liquid storage tank 2, the tube 5A is disposed in the storage part 2a of the liquid storage tank 2. Furthermore, the liquid stored in the storage part 2a is introduced into the housing 31 (i.e., the device body 3) through the tube 5A.

[0226] Furthermore, a helical spring 6A is arranged around the tube 5A to maintain its extension along the length of the tube 5A. By arranging such a helical spring 6A around the tube 5A, when the device body 3 is housed in the liquid storage tank 2, the tube 5A can be wound without bending, and the tube 5A can be neatly housed in the liquid storage tank 2. Moreover, by arranging the helical spring 6A around the tube 5A, when the device body 3 is pulled out from the liquid storage tank 2, the tube 5A can be neatly extended from its wound state.

[0227] Furthermore, a liquid flow path 32 is formed inside the housing 31 (i.e., an example of the device body 3), which allows liquid introduced via the pipe 5A to pass through and be supplied to the nozzle 4. Figure 32 In the oral cleaning device 100 shown, the liquid flow path 32 is provided inside the housing 31 (i.e., inside the device body 3) such that one end is connected to the inner space of the nozzle mounting portion 3111 and the other end is connected to the inner space of the tube mounting portion 3132. Thus, liquid introduced through the tube 5A is supplied to the nozzle 4 through the liquid flow path 32.

[0228] Additionally, the liquid flow path 32 includes a suction path 321 disposed on the upstream side of the liquid flow path 32 and a discharge path 322 disposed on the downstream side of the liquid flow path 32, the suction path 321 and the discharge path 322 being connected via a pump 33. Furthermore, a suction valve (not shown) is provided between the pump chamber 333 and the suction path 321, and a discharge valve (not shown) is provided between the pump chamber 333 and the discharge path 322.

[0229] Furthermore, a pump drive mechanism 34 is disposed inside the housing 31 (i.e., an example of the device body 3). By using the pump drive mechanism 34 to operate the pump 33, the liquid in the storage section 2a is drawn up through the pipe 5A and discharged (more specifically, sprayed out) from the top of the nozzle 4 through the liquid flow path 32.

[0230] so, Figure 32 The oral cleaning device 100 shown includes a pump 33 and a pump drive mechanism 34 for driving the pump 33, thus becoming a device for discharging liquid by driving the pump 33.

[0231] In addition, Figure 32 In the oral cleaning device 100 shown, the pump 33 includes: a pump chamber 333, a suction passage 321 and a discharge passage 322 communicating with the pump chamber 333; a cylinder 332 configured to communicate with the lower end of the pump chamber 333; and a piston 331 disposed within the cylinder 332.

[0232] The piston 331 is connected to the pump drive mechanism 34, and reciprocates linearly in the vertical direction within the cylinder 332 via the pump drive mechanism 34. Furthermore, the volume of the pump chamber 333 changes due to the reciprocating linear motion of the piston 331 within the cylinder 332.

[0233] Specifically, when piston 331 moves downward within cylinder 332, the volume of pump chamber 333 increases, and liquid in reservoir 2 flows into pump chamber 333 via pipe 5A and suction passage 321. Then, with liquid flowing into pump chamber 333, when piston 331 moves upward within cylinder 332, the volume of pump chamber 333 decreases, and liquid in pump chamber 333 is supplied to nozzle 4 via discharge passage 322. Furthermore, the liquid supplied to nozzle 4 is discharged (more specifically, ejected) from the tip of nozzle 4.

[0234] Thus, in Figure 32In the oral cleaning device 100 shown, the piston 331 moves downward within the cylinder 332 to perform a suction process, drawing liquid into the pump chamber 333, and moves upward to perform a discharge process, expelling liquid from the pump chamber 333 to the outside. That is, the piston 331 reciprocates linearly between the top dead center and the bottom dead center, thereby alternately performing the suction and discharge processes. Therefore, when the piston 331 reciprocates once in the vertical direction from the top dead center, the suction and discharge processes are each performed once.

[0235] By configuring the structure in this way, liquid is intermittently discharged from the top of the nozzle 4 installed on the main body 3 of the device.

[0236] Furthermore, the pump drive mechanism 34 includes a motor 341, which drives the piston 331 to reciprocate linearly in the vertical direction within the cylinder 332.

[0237] Specifically, the pump drive mechanism 34 includes a motor 341 and a conversion mechanism 344 that converts the rotational motion of the motor 341 into reciprocating linear motion. Furthermore, a piston 331 is connected to this conversion mechanism 344, causing the piston 331 to reciprocate linearly in the vertical direction within the cylinder 332. The motor 341 is driven by power supplied from a battery (e.g., a rechargeable battery, dry cell battery, etc.) housed inside the device body 3, or by external power.

[0238] Furthermore, in Figure 32 In the oral cleaning device 100 shown, the pump drive mechanism 34 includes a reduction mechanism 342 that slows down the rotational speed of the motor 341, and a transmission mechanism 343 that transmits the reduced rotational motion to the conversion mechanism 344. Therefore, in Figure 32 In the oral cleaning device 100 shown, when the rotational speed (i.e., revolutions per unit time) of the motor 341 is reduced to a predetermined rotational speed (i.e., revolutions per unit time) by the reduction mechanism 342, it is converted into reciprocating linear motion by the conversion mechanism 344.

[0239] Furthermore, in Figure 32 The oral cleaning device 100 shown can also clean the oral cavity more efficiently.

[0240] Specifically, it includes a speed-changing mechanism 345 that makes the moving speed of the piston 331 during the pump drive mechanism 34 different from the moving speed of the piston 331 during the suction process. Furthermore, the piston 331 reciprocates once in such a way that the time spent in the suction process is shorter than the time spent in the discharge process.

[0241] exist Figure 32In the oral cleaning device 100 shown, the pump drive mechanism 34 also has a speed change mechanism 345 that makes the moving speed of the piston 331 during the delivery process different from the moving speed of the piston 331 during the suction process. Moreover, the speed change mechanism 345 has elliptical gears 3451 and 3452 as non-circular gears, and the speed change mechanism 345 is composed of two elliptical gears 3451 and 3452.

[0242] Furthermore, in Figure 32 In the oral cleaning device 100 shown, the pump drive mechanism 34 also has an auxiliary mechanism 346 for the movement of the auxiliary piston 331.

[0243] As such an oral cleaning device 100, it can also perform the same function and effect as the oral cleaning device 100 shown in the above embodiments and their modifications.

[0244] In addition, Figure 32 The oral cleaning device 100 shown has the same structure as the pump drive mechanism 34 shown in the above embodiment (i.e., a pump drive mechanism 34 with an auxiliary mechanism 346), but it can also be configured as a pump drive mechanism 34 without the auxiliary mechanism 346. Furthermore, there is no particular limitation on the type of pump; similar to the above embodiment, various types of pumps can be used.

[0245] In addition, Figure 32 The example shown is a can-telescopic oral cleaning device 100 in which the device body 3 is rotated relative to the liquid storage tank 2 to make the device body 3 into a pulled-out state, but it is not limited to such a structure. For example, it can be configured as a can-telescopic oral cleaning device in which the device body 3 is pulled out by pulling the device body 3 in the sliding direction.

[0246] [Functions and Effects]

[0247] The following describes the characteristic structure of the nozzle for the oral cleaning device and the oral cleaning device shown in the above embodiments and their modifications, as well as the effects obtained therefrom.

[0248] (Technology 1) The nozzle 4 (more specifically, the nozzle for an oral cleaning device) shown in the above embodiments and their variations has a nozzle housing 40 with a flow path P1 having an inlet P1a and an outlet P1b.

[0249] Furthermore, the nozzle 4 is configured to introduce fluid (e.g., liquid such as water or gas such as air) with a pressure of 1 MPa or more and 4 MPa or less into the flow path P1, thereby discharging it from the outlet P1b with a discharge load of 0.19 N or more and 0.38 N or less.

[0250] If nozzle 4 with this structure is used, the dirt removal effect can be further improved, thus further improving the cleaning effect in the oral cavity.

[0251] Thus, based on the above embodiments and their variations, a nozzle 4 (more specifically, a nozzle for an oral cleaning device) that can further improve the cleaning effect in the oral cavity can be obtained.

[0252] (Technology 2) Alternatively, in (Technology 1) described above, the flow path P1 may include: an inlet flow path P12 (i.e., an example of the first flow path); and a first narrowing flow path (more specifically, a throttling section) P13, which is continuously arranged downstream of the inlet flow path P12 (i.e., an example of the first flow path), and the flow path cross-sectional area is smaller than that of the inlet flow path P12 (i.e., an example of the first flow path). Alternatively, the flow path P1 may include: an enlarging flow path P14 (more specifically, a compression chamber), which is continuously arranged downstream of the first narrowing flow path P13, and the flow path cross-sectional area is larger than that of the first narrowing flow path P13; and a second narrowing flow path P15 (more specifically, a discharge flow path), which is continuously arranged downstream of the enlarging flow path P14, and the flow path cross-sectional area is smaller than that of the enlarging flow path P14.

[0253] This allows for more efficient reduction of pressure loss, enabling fluids (such as liquids like water or gases like air) to be discharged more reliably from outlet P1b with a discharge load of 0.19 N or more and 0.38 N or less.

[0254] Furthermore, by incorporating a first narrowing flow path midway through flow path P1, gases such as air introduced into flow path P1 can diffuse. This allows for more efficient pressurization, dissolution, or mixing of liquids and gases, increasing the generation of droplets, microbubbles, and cavitation bubbles. Consequently, the shear force, pressure fluctuations, and vibrations generated when the fluid discharged from outlet P1b contacts the cleaning surfaces such as tooth surfaces increase. That is, the force for peeling off dirt adhering to tooth surfaces can be further increased. As a result, the cleaning force is increased, further improving the cleaning effect in the oral cavity.

[0255] (Technology 3) Alternatively, in (Technology 2) described above, the nozzle housing 40 may also include a first flow path structure portion 424 forming an inlet flow path P12 (i.e., an example of the first flow path) internally, and a second flow path structure portion 425 forming a first narrowing flow path P13 internally. Furthermore, the nozzle housing 40 may also include a third flow path structure portion 426 forming an enlarging flow path P14 internally. Moreover, the second flow path structure portion 425 may be integrally formed with at least one of the flow path structure portions 424 and 426.

[0256] In this way, it is not necessary to insert other components into the flow path P1 to form the first narrowed flow path P13, thus making it easier to obtain a nozzle 4 with the first narrowed flow path P13. Furthermore, when using other components to form the first narrowed flow path P13, tiny gaps may form within the flow path P1, resulting in useless pressure loss and reduced cleaning force. However, if the second flow path structure 425 is integrally formed with at least one of the first flow path structure 424 and the third flow path structure 426, the formation of tiny gaps within the flow path P1 can be more reliably suppressed, thereby more reliably suppressing the generation of useless pressure loss. As a result, the reduction in cleaning force can be significantly reduced.

[0257] Furthermore, if the second flow path structure portion 425 is integrally formed with at least one of the first flow path structure portion 424 and the third flow path structure portion 426, the strength of the nozzle housing 40 can be further improved. As a result, even when fluid is introduced into the flow path P1 from the inlet P1a at a high pressure of 1 MPa or more and 4 MPa or less, deformation and breakage of the nozzle housing 40 can be suppressed more reliably.

[0258] (Technology 4) Alternatively, in (Technology 3) above, the second flow path structure 425 may be formed of the same material as the flow path structure of at least one of the first flow path structure 424 and the third flow path structure 426.

[0259] In this way, it is possible to more reliably suppress the formation of unexpected steps and gaps at the connection between the second flow path structure 425 and at least one of the first flow path structure 424 and the third flow path structure 426, and to more reliably suppress the generation of useless pressure loss. As a result, it is possible to greatly suppress the reduction of cleaning force.

[0260] (Technology 5) In any of the above (Technology 2) to (Technology 4)), the second narrowing flow path P15 may be a cone shape with a wider downstream side, and the cone angle θ is more than 0 degrees and less than 5 degrees.

[0261] In this way, the fluid compressed in the enlarged flow path P14 and introduced into the second narrowed flow path P15 can be discharged from the outlet P1b along the wall that divides the second narrowed flow path P15. This more reliably prevents the fluid from being discharged only from the central portion of the outlet P1b, thus preventing the fluid with a core from contacting the cleaning surface such as the tooth surface. Consequently, it more reliably prevents situations where the fluid only contacts a narrow area, resulting in reduced cleaning efficiency, or where the surface pressure increases, leading to lower sensory evaluation during use.

[0262] Thus, if the shape of the second narrowing flow path P15 is set to a cone shape with a wider downstream side and a cone angle θ of 0 degrees or more and 5 degrees or less, the fluid can contact a larger area of ​​the cleaning surface, such as the tooth surface, while maintaining the cleaning force (dirt removal efficiency). That is, a fluid with high cleaning force (i.e., an example of dirt removal efficiency) can contact a larger area. Therefore, oral cavity cleaning can be performed more effectively and efficiently.

[0263] (Technology 6) The oral cleaning device 100 shown in the above embodiments and their modifications includes: a nozzle 4 (more specifically, a nozzle for an oral cleaning device) shown in any of the above technologies (Technology 1) to (Technology 5); and a holding part 10 (i.e., an example of a holding part), wherein the nozzle 4 (more specifically, a nozzle for an oral cleaning device) is mounted on the holding part 10 (i.e., an example of a holding part).

[0264] In this way, an oral cleaning device 100 can be obtained that can further improve the cleaning effect in the oral cavity. Specifically, an oral cleaning device 100 can be obtained that can achieve the functions and effects shown in any of the above-mentioned (Technology 1) to (Technology 5).

[0265] (Technology 7) Alternatively, in the above-described (Technology 6), the oral cleaning device 100 may also include: a liquid storage tank 2 for storing liquid; a pump 33 for drawing in the liquid stored in the liquid storage tank 2 and delivering the liquid to the nozzle 4; and a pump drive mechanism 34 for driving the pump 33. Furthermore, the pump 33 may also have a piston 331 that reciprocates linearly in one direction.

[0266] Alternatively, the pump 33 can also cause the piston 331 to reciprocate linearly via the pump drive mechanism 34, thereby alternately performing the suction process of drawing liquid into the pump 33 and the discharge process of discharging liquid from the pump 33. Moreover, the piston 331 can be reciprocated once in such a way that the time spent in the suction process is different from the time spent in the discharge process.

[0267] In this way, the liquid can be discharged with a different water flow than when the ratio of the time spent in the delivery process to the time spent in the suction process is 1:1. As a result, oral cleaning and other procedures can be performed more efficiently.

[0268] [other]

[0269] The above description illustrates the nozzle for the oral cleaning device and the oral cleaning device of this disclosure. However, the above embodiments and their variations are merely illustrative of the technology disclosed. Therefore, various changes, substitutions, additions, omissions, etc., can be made within the scope of the claims or their equivalents.

[0270] For example, it is possible to configure a nozzle for an oral cleaning device and an oral cleaning device that are appropriately combined with the structures described in the above embodiments and their variations.

[0271] Furthermore, in the above embodiments and their modifications, an oral cleaning device is illustrated in which a liquid reservoir 2 (i.e., an example of a liquid reservoir) is formed in the holding part 10 (i.e., an example of a holding part), and a power supply component such as a rechargeable battery is built into the holding part 10 (i.e., an example of a holding part), enabling it to be used without the use of an external power source. However, the structure of the oral cleaning device is not limited to such a structure, and various structures can be adopted.

[0272] For example, it can also be configured as an oral cleaning device 100 that receives power from an external power source via power line 36A to operate the pump 33, etc.

[0273] In addition, the above structure can also be applied to oral cleaning devices with structures other than the oral cleaning device 100 described in the above embodiments and their modifications.

[0274] In addition, the specifications (shape, size, layout, etc.) of the nozzle housing, grip, and other details can be changed appropriately.

[0275] Industrial availability

[0276] As described above, the nozzle and oral cleaning device of the present invention can further improve the cleaning effect in the oral cavity, and therefore can be used in various oral cleaning nozzles and oral cleaning devices, such as those for home use and commercial use.

[0277] Explanation of reference numerals in the attached figures

[0278] 100. Oral cleaning device; 10. Support unit; 10a. Operating switch; 11. Housing; 111. Nozzle mounting part; 2. Liquid storage tank; 2a. Storage part; 21. Cylindrical body; 211. Liquid supply cover; 22. Bottom wall; 221. Bottom surface; 3. Main body of the device; 31. Housing; 31a. Handle holding part; 31b. Hose holding part; 311. Top wall; 3111. Nozzle mounting part; 312. Peripheral wall; 3121. Recess; 313. Bottom wall; 3131. Bottom surface; 3132. Tube mounting part; 32. Liquid flow path; 321. Suction path; 3211. Tube; 322. Delivery path; 3221. Tube; 33. Pump; 331. Piston; 34. Pump drive mechanism; 332. Cylinder; 333. Pump chamber; 34. Pump drive mechanism: 34A; Hose: 341; Motor: 3411; Motor shaft: 342; Reduction mechanism: 3421; Pinion gear: 3422; Reduction gear: 3423; First output shaft: 343; Transmission mechanism: 3431; First transmission gear: 3432; Second transmission gear: 3433; Second output shaft: 344; Conversion mechanism: 3441; First gear; 3442; Second gear; 3443; Third output shaft; 3444; Cam; 3445; Screw; 3446; Rod; 34461; Connecting shaft; 345; Speed ​​change mechanism; 3451; Elliptical gear; 3452; Elliptical gear; 346; Auxiliary mechanism: 3461; Spring seat: 3462; Helical spring: 3463. A pair of shafts: 3464, sliding member: 34641, pressing part: 35A, wiring: 36A, power cord: 37A, power switch: 38aA, hydraulic switch: 38bA, hydraulic switch: 4, nozzle: 40, nozzle housing: 40a, thick-walled part: 40b, thin-walled part: 41, connecting part: 411, inner wall surface: 42, housing body: 421, rod part: 422, bent part: 423, top part: 424, first flow path structure part: 4241, first inner wall surface; 42411, upstream inclined surface; 42412, downstream inclined surface; 425, second flow path structure part; 4251, second inner wall surface; 426, third flow path structure part; 4261, third inner wall surface; 42611, upstream side Vertical plane; 42612, downstream vertical plane; 427, fourth flow path structure; 4271, fourth inner wall surface; 42711, first section line; 42712, second section line; 4A1, pressure gauge; 4A2, connecting fixture; 5, first forming component; 51, first wall portion; 511, first abutting surface; 5111, first positioning portion; 5112, first notch portion; 512, first recess; 513, first protrusion; 5A, tube; 6, second forming component; 6A, coil spring; 61, second wall portion; 611, second abutting surface; 6111, second positioning portion; 6112, second notch portion; 612, second recess; 7, inflow space; 81, joint surface; 82, heat fusion portion; 91, first mold;92. Second mold; 93. Resin gate; a. Long axis; b. Short axis; C1. Flow path axis; D. Maximum feed rate; d1. Diameter; d2. Diameter; d3. Diameter; d4. Diameter; d5. Depth; L; Length; L2; L3; L4; Length; P1. Flow path; P1a. Inlet; P1b. Outlet; P12. Inlet flow path; P13. First narrowing flow path; P14. Enlarging flow path; P15. Second narrowing flow path; W1. Width; θ. Cone angle.

Claims

1. A nozzle for an oral cleaning device, comprising a nozzle housing having a flow path having an inlet and an outlet, wherein, The oral cleaning device uses a nozzle configured such that fluid with a pressure of 1 MPa or more and 4 MPa or less is introduced into the flow path from the inlet and discharged from the outlet with a discharge load of 0.19 N or more and 0.38 N or less.

2. The nozzle for the oral cleaning device according to claim 1, wherein, The flow path includes: 1st flow path; The first narrowing flow path is continuously arranged on the downstream side of the first flow path, and the cross-sectional area of ​​the flow path is smaller than that of the first flow path; An enlarged flow path is continuously arranged downstream of the first reduced flow path, and the cross-sectional area of ​​the flow path is larger than that of the first reduced flow path; as well as The second narrowing flow path is continuously arranged downstream of the widening flow path, and its cross-sectional area is smaller than that of the widening flow path.

3. The nozzle for the oral cleaning device according to claim 2, wherein, The nozzle housing includes: a first flow path structure portion that forms the first flow path internally; and a second flow path structure portion that forms the first narrowing flow path internally. And the third flow path structure, which internally forms the enlarged flow path, The second flow path structure is integrally formed with the flow path structure of at least one of the first flow path structure and the third flow path structure.

4. The nozzle for the oral cleaning device according to claim 3, wherein, The second flow path structure is formed of the same material as the flow path structure of at least one of the first and third flow path structures.

5. The nozzle for the oral cleaning device according to claim 2, wherein, The second narrowing flow path is a cone shape with a wider downstream side, and the cone angle is above 0 degrees and below 5 degrees.

6. An oral cleaning device, wherein, The oral cleaning device includes: a nozzle for an oral cleaning device according to any one of claims 1 to 5; and a holding part, wherein the nozzle for the oral cleaning device is detachably mounted on the holding part.

7. The oral cleaning device according to claim 6, wherein, This oral cleaning device also features: A liquid storage tank, used to store liquids; A pump that draws in liquid stored in the reservoir and delivers the liquid to the oral cleaning device through a nozzle; and Pump drive mechanism, which drives the pump, The pump has a piston that reciprocates linearly in one direction. By using the pump drive mechanism to make the piston reciprocate linearly, the suction process of drawing liquid into the pump and the discharge process of pumping liquid out of the pump are performed alternately. The piston can be reciprocated once in a manner that makes the time spent in the suction process different from the time spent in the delivery process.

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