A spray arm mechanism and a dishwasher having the same

Abstract

This utility model discloses a spray arm mechanism and a dishwasher thereof. The spray arm mechanism includes: a main spray arm with a water inlet at its top and an active part located around the water inlet; and a secondary spray arm, which is oscillating back and forth above the main spray arm. A driven part is provided on the secondary spray arm at a position corresponding to the active part, and the driven part is drively connected to the active part so that the rotation of the main spray arm can synchronously drive the oscillation of the secondary spray arm. The spray arm mechanism of this utility model increases the rinsing angle, enriches the spraying methods, and effectively improves the cleaning effect of the dishwasher.

Description

Technical Field

[0001] This utility model relates to the field of dishwasher technology, and in particular to a spray arm mechanism and the dishwasher thereof. Background Technology

[0002] Household dishwashers typically clean dishes by using a spray of water, combined with detergents and heating. However, due to the low water pressure in the middle water channel, the spray arms in most dishwashers use a single circular spray pattern, resulting in only a single rinsing angle and position. This leaves many hard-to-reach areas unwashed, such as the inner walls of deep containers. Utility Model Content

[0003] This utility model aims to at least partially solve one of the problems existing in the prior art. To this end, this utility model proposes a spray arm mechanism that increases the rinsing angle, enriches the spraying methods, and effectively improves the cleaning effect of the dishwasher. This utility model also proposes a dishwasher.

[0004] The spray arm mechanism described above is implemented through the following technical solution:

[0005] A spray arm mechanism includes: a main spray arm with a water inlet at the top and an active part located around the water inlet; and a secondary spray arm, which is oscillating back and forth around its central axis and disposed above the main spray arm, with a driven part at a position corresponding to the active part, the driven part being drively connected to the active part so that the secondary spray arm can be synchronously driven to oscillate when the main spray arm rotates.

[0006] In some embodiments, the driving part is a closed annular variable pitch threaded rib, the radius of which gradually increases and then gradually decreases along a first direction; the driven part is a gear, which is engaged with the annular variable pitch threaded rib.

[0007] In some embodiments, the active part is a closed annular variable pitch groove, the radius of which gradually increases and then gradually decreases along a first direction; the driven part is a positioning protrusion, which is movably inserted into the annular variable pitch groove.

[0008] In some embodiments, the main spray arm includes an upper cover and a lower cover that are fixedly connected to each other. The upper cover and the lower cover are arranged together to form a first flow channel. The water inlet, a plurality of first spray holes and the active part are provided on the top of the upper cover. The active part is integrally formed on the top of the upper cover.

[0009] In some embodiments, reinforcing portions are provided on the two opposite outer sides of the water inlet, the reinforcing portions including spaced strip connecting ribs, the opposite ends of the strip connecting ribs being integrally formed with the upper cover and the active part, respectively.

[0010] In some embodiments, an upwardly extending annular support portion is integrally formed around the periphery of the inlet.

[0011] In some embodiments, the main spray arm includes a spray arm body and a cam. The spray arm body has a water inlet and a plurality of first spray holes on its top. The cam is fixedly connected to the top of the spray arm body and located around the water inlet. The active part is integrally formed on the top of the cam.

[0012] In some embodiments, an annular support portion is provided at the center of the cam, and the water inlet is connected to the interior of the annular support portion.

[0013] In some embodiments, a clearance portion is provided at the position of the cam corresponding to the first spray hole; and / or two downwardly extending reinforcing ribs are integrally formed at the bottom of the cam, the two reinforcing ribs being located on opposite outer sides of the spray arm body.

[0014] In some embodiments, the auxiliary spray arm includes a first whistle spray arm and a rotating component, wherein the first whistle spray arm is connected to the rotating component, and a gear or positioning protrusion is integrally formed on the outer wall of the rotating component.

[0015] In some embodiments, the auxiliary spray arm further includes a second whistle spray arm, wherein the first whistle spray arm is connected and fixed to the second whistle spray arm via the rotating member.

[0016] The dishwasher described above is achieved through the following technical solution:

[0017] A dishwasher includes a dish rack assembly and a spray arm mechanism as described above, the spray arm mechanism being detachably mounted to the bottom of the dish rack assembly.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects:

[0019] 1. The spray arm mechanism of this utility model has a driving connection between the active part of the main spray arm and the driven part of the auxiliary spray arm, so that when the main spray arm rotates, it can reliably drive the auxiliary spray arm to swing back and forth around its central axis. In this way, with the cooperation of the main spray arm and the auxiliary spray arm, the rinsing angle is increased, the spraying mode is enriched, and the cleaning effect of the dishwasher is effectively improved. At the same time, the back-and-forth swinging auxiliary spray arm significantly improves the cleaning effect on a certain dish rack component; 2. The spray arm mechanism of this utility model has an integrally formed driven part on the top of the upper cover of the main spray arm, and the driven part is integrated on the auxiliary spray arm, so that the overall structure of the spray arm mechanism is simpler, occupies less space, and effectively reduces costs. Attached Figure Description

[0020] Figure 1 This is an exploded view of the bowl basket assembly and spray arm mechanism in Embodiment 1 of this utility model;

[0021] Figure 2 This is a cross-sectional view of the spray arm mechanism installed on the bowl assembly in Embodiment 1 of this utility model;

[0022] Figure 3 This is a schematic diagram of the main spray arm in Embodiment 1 of this utility model;

[0023] Figure 4 This is a top view of the main spray arm in Embodiment 1 of this utility model;

[0024] Figure 5 This is a schematic diagram of the rotating component in Embodiment 1 of this utility model;

[0025] Figure 6 This is a cross-sectional view of the rotating component in Embodiment 1 of this utility model;

[0026] Figure 7 This is an exploded view of the bowl basket assembly and spray arm mechanism in Embodiment 3 of this utility model;

[0027] Figure 8 This is a schematic diagram of the structure of the spray arm mechanism installed on the bowl assembly in Embodiment 3 of this utility model;

[0028] Figure 9 This is a cross-sectional view of the spray arm mechanism installed on the bowl assembly in Embodiment 3 of this utility model;

[0029] Figure 10 This is a top view of the spray arm mechanism in Embodiment 3 of this utility model;

[0030] Figure 11 This is a top view of the cam in Embodiment 3 of this utility model;

[0031] Figure 12 This is a schematic diagram of the cam structure in Embodiment 3 of this utility model;

[0032] Figure 13 This is a cross-sectional view of the spray arm mechanism installed on the bowl assembly in Embodiment 4 of this utility model;

[0033] Figure 14 This is a top view of the cam in Embodiment 4 of this utility model;

[0034] Figure 15 This is a schematic diagram of the cam structure in Embodiment 4 of this utility model;

[0035] Figure 16 This is a schematic diagram of the rotating component in Embodiment 4 of this utility model.

[0036] In the diagram: 1-Main spray arm, 101-Water inlet, 102-First flow channel, 103-First spray hole, 104-Water outlet, 105-Annular variable pitch threaded rib, 106-Annular variable pitch groove, 1071-Strip connecting rib, 1072-Arc connecting rib, 108-Annular support part, 11-Upper cover, 12-Lower cover, 13-Spray arm body, 131-Boss, 14-Cam, 141-Fixing column, 142-Clearing part, 143-Reinforcing rib;

[0037] 2-Secondary spray arm, 201-Water inlet, 203-Second spray hole, 21-First flute spray arm, 22-Second flute spray arm, 23-Rotating component, 231-Gear, 2311-Spur gear, 2312-Slot, 232-Positioning protrusion;

[0038] 31-Main water pipe, 32-Connecting water pipe, 321-Outlet connector;

[0039] 41-Spray arm support, 42-Spray arm pivot;

[0040] 5-bowl basket assembly. Detailed Implementation

[0041] The following embodiments illustrate the present invention, but the present invention is not limited to these embodiments. Modifications to the specific implementation of the present invention or equivalent substitutions for some technical features, without departing from the spirit of the present invention, should all be covered within the scope of the technical solution claimed by the present invention.

[0042] Example 1

[0043] refer to Figure 1-6 This embodiment provides a spray arm mechanism, including a main spray arm 1, a secondary spray arm 2, a water pipe assembly, and a rotating shaft assembly. The main spray arm 1 is rotatably connected to the water pipe assembly via the rotating shaft assembly, and the main spray arm 1 can rotate around the rotating shaft assembly (i.e., line A1). See [link to documentation]. Figure 2The auxiliary spray arm 2 is positioned above and linked to the main spray arm 1, so that when the main spray arm 1 rotates, it can synchronously drive the auxiliary spray arm 2 to swing back and forth around its central axis (i.e., line A2). See [link to relevant documentation]. Figure 2 Therefore, when the main spray arm 1 is linked with the auxiliary spray arm 2, the spray water jets intersect, increasing the rinsing angle, enriching the spraying methods, and effectively improving the cleaning effect of the dishwasher. At the same time, the back-and-forth swinging auxiliary spray arm 2 significantly improves the cleaning effect on a certain dish rack component.

[0044] The main spray arm 1 has an inlet 101 at its top and an active part (not shown in the figure) located around the inlet 101. The main spray arm 1 has a first flow channel 102 and multiple first nozzles 103. The inlet 101 is connected to the first nozzles 103 through the first flow channel 102. In addition, water outlets 104 are provided at opposite ends of the bottom of the main spray arm 1, and the water outlets 104 are connected to the first flow channel 102. The auxiliary spray arm 2 is swayably arranged above the main spray arm 1. The auxiliary spray arm 2 has an inlet 201, a second flow channel (not shown in the figure), and multiple second nozzles 203. The inlet 201 is connected to the second nozzles 203 through the second flow channel. A driven part (not shown in the figure) is provided at the position of the auxiliary spray arm 2 corresponding to the active part. The driven part is connected to the active part for transmission, so that the main spray arm 1 is linked with the auxiliary spray arm 2, ensuring that the auxiliary spray arm 2 can swing synchronously when the main spray arm 1 rotates. It should be noted that there can also be two auxiliary spray arms 2. In this case, the two auxiliary spray arms 2 are arranged side by side at intervals on the left and right sides of the active part of the main spray arm 1. The driven parts of the two auxiliary spray arms 2 are connected to the active part on the main spray arm 1 so that the two auxiliary spray arms 2 can reliably and synchronously drive the main spray arm to swing back and forth when it rotates.

[0045] refer to Figure 2-5 Specifically, the driving part is a closed annular variable-pitch threaded rib 105. The radius of the annular variable-pitch threaded rib 105 gradually increases and then gradually decreases along a first direction, so that the radius of the annular variable-pitch threaded rib 105 changes in a certain regular pattern. The first direction is a clockwise direction, but it can also be designed to be counterclockwise. The driven part is a gear 231, which is connected to the annular variable-pitch threaded rib 105. In this embodiment, the gear 231 has n straight teeth 2311, and a groove 2312 is formed between two adjacent straight teeth 2311. The annular variable-pitch threaded rib 105 is inserted into one of the grooves 2312 and can move between the grooves 2312. Thus, by the engagement of the annular variable-pitch threaded rib 105 with the groove 2312 on the gear 231, it is ensured that the main spray arm 1 can reliably drive the auxiliary spray arm 2 to swing when rotating.

[0046] See Figure 3-4The annular variable-pitch threaded bar 105 has a center point Q and four special points, namely P1, P2, P3, and P4. The radius P1Q < radius P2Q = radius P4Q < radius P3Q. Furthermore, the distance (i.e., radius) from point P1 through P2 to P3 gradually increases from point Q, while the distance from point P3 through P4 to P1 gradually decreases from point Q (i.e., radius). See also... Figure 5-6 The circular dashed line L is the pitch circle on gear 231, where M1 and M2 are the intersection points of the midpoints of the two outermost spur teeth on the pitch circle, and M0 is the intersection point of the midpoints of the two middle spur teeth on the circular dashed line L. Let the arc length between two adjacent spur teeth 2311 be a, then the arc length M1M2 = (n-2) × a, where n is the total number of spur teeth on the gear.

[0047] Since the arc length M1M2 = (n-2) × a, the distance can be set as 2 × (P3Q - P1Q) = arc length M1M2. When the annular variable pitch thread rib 105 meshes with the gear 231, it satisfies that point M0 on the gear 231 meshes with point P2 or P4 on the annular variable pitch thread rib 105; when the gear 231 rotates to position M2, the gear 231 meshes with point P1, at which time the gear is at the innermost side of the annular variable pitch thread rib 105; when the gear 231 rotates to position M1, the gear 231 meshes with point P3, at which time the gear is at the outermost side of the annular variable pitch thread rib 105. When gear 231 meshes with the annular variable-pitch thread rib 105, as the annular variable-pitch thread rib 105 gradually increases in size, gear 231 rotates from the innermost side to the outermost side; conversely, as the annular variable-pitch thread rib 105 gradually decreases in size, gear 231 rotates from the outermost side to the innermost side, where the rotation angle between the outermost and innermost sides is β. Therefore, when the main spray arm 1 rotates one revolution, the auxiliary spray arm 2 swings back and forth once, forming a spray angle range of β. During this process, the spray water jets of the main and auxiliary spray arms intersect, increasing the rinsing angle and enriching the spraying method. At the same time, compared with the existing auxiliary spray arm that rotates or turns in the same direction, the back-and-forth swinging auxiliary spray arm 2 has a more specific cleaning range, which is beneficial to significantly improve the cleaning effect on a certain dish rack component (e.g., the upper dish rack). Where n=2~12, preferably n=8 or 10.

[0048] refer to Figure 1-4In this embodiment, the main spray arm 1 includes an upper cover 11 and a lower cover 12 fixedly connected to each other. The upper cover 11 and the lower cover 12 enclose each other to form a first flow channel 102. The upper cover 11 has a water inlet 101, multiple first spray holes 103, and an annular variable-pitch threaded rib 105 at its top. The annular variable-pitch threaded rib 105 is integrally formed and protrudes from the top of the upper cover 11. At least one water outlet 104 is provided at each of the opposite ends of the bottom of the lower cover 12. It can be seen that by integrally forming the driven part (i.e., the annular variable-pitch threaded rib 105) on the top of the upper cover 11 of the main spray arm 1, rapid processing and forming are facilitated, while reducing the number of parts and assembly processes. Furthermore, since the driven part is also integrated into the auxiliary spray arm 2, the overall structure of the spray arm mechanism is simpler, occupies less space, and effectively reduces costs.

[0049] Specifically, reinforcing sections are provided on the two opposite outer sides of the inlet 101. Each reinforcing section includes spaced-apart strip-shaped connecting ribs 1071. The opposite ends of each strip-shaped connecting rib 1071 are integrally formed with the upper cover 11 and the annular variable-pitch threaded rib 105, respectively, to enhance the overall strength of the upper cover 11 and the annular variable-pitch threaded rib 105. Furthermore, the reinforcing section also includes arc-shaped connecting ribs 1072. The opposite ends of each arc-shaped connecting rib are integrally formed with the upper cover 11, and each arc-shaped connecting rib is integrally formed with a corresponding plurality of strip-shaped connecting ribs 1071.

[0050] An upwardly extending annular support portion 108 is integrally formed around the water inlet 101. This annular support portion 108 is integrally formed with the top of the upper cover plate 11 to strengthen the water inlet 101 and facilitate reliable support of the spray arm support 105 on the rotating shaft assembly through the annular support portion 108.

[0051] refer to Figure 1-2In this embodiment, the auxiliary spray arm 2 includes a first flute spray arm 21 and a rotating member 23. The first flute spray arm 21 is connected to the rotating member 23. The first flute spray arm 21 is provided with a water inlet 201 and multiple second spray holes 203. A gear 231 is integrally formed on the outer wall of the rotating member 23. In addition, the auxiliary spray arm 2 also includes a second flute spray arm 22. The second flute spray arm 22 is connected and fixed to the first flute spray arm 21 through the rotating member 23. The second flute spray arm 22 is provided with multiple second spray holes 203. The second flow channel is defined by the interior of the first flute spray arm 21, the interior of the rotating member 23, and the interior of the second flute spray arm 22. In this way, with the cooperation of the second flute spray arm 22, the rotating member 23, and the first flute spray arm 21, the auxiliary spray arm can reliably link with the main spray arm while increasing the spray range of the auxiliary spray arm 2. Of course, in other embodiments, the second flute spray arm 22 can be omitted. In this case, the second flow channel can be defined by the inside of the first flute spray arm 21, or by the inside of the first flute spray arm 21 and the inside of the rotating member 23. Alternatively, both the second flute spray arm 22 and the rotating member 23 can be omitted. In this case, the gear 231 can be integrated into the outer wall of the first flute spray arm 21. Correspondingly, the end of the first flute spray arm 21 away from the water inlet can be designed as a closed end.

[0052] refer to Figure 1-2 The spray arm mechanism also includes a water pipe assembly and a rotating shaft assembly. The water pipe assembly includes a main water pipe 31, which is located above the main spray arm 1 and arranged side by side with the auxiliary spray arm 2 at intervals. The water outlet of the main water pipe 31 is connected to the water inlet 101 of the main spray arm 1 through the rotating shaft assembly, so as to provide driving water or cleaning water to the main spray arm, while ensuring that the main water pipe and the auxiliary spray arm do not interfere with each other. In addition, the water pipe assembly also includes a connecting water pipe 32, which is located behind the auxiliary spray arm 2. The outlet end of the connecting water pipe 32 is connected to the inlet 201 of the auxiliary spray arm 2. The inlet end of the connecting water pipe 32 is connected to or not connected to the inlet end of the main water pipe 31. In this embodiment, the outlet end of the connecting water pipe 32 is provided with an outlet connector 321 extending toward the auxiliary spray arm 2. The outlet connector 321 is inserted into the inlet of the auxiliary spray arm 2, so as to satisfy the water supply of the auxiliary spray arm and ensure that the auxiliary spray arm 2 can swing around the outlet connector 321.

[0053] The rotating shaft assembly includes a spray arm support 41 and a spray arm rotating shaft 42. The spray arm support 41 is located between the bottom of the main water pipe 41 and the top of the annular support portion 108 of the main spray arm 1. The lower end of the spray arm rotating shaft 42 is vertically inserted from top to bottom through the annular support portion 108 of the main spray arm 1 and inserted into the water inlet 101 of the main spray arm 1. The lower end of the spray arm rotating shaft 42 is screwed to the main spray arm 1, and the upper end is screwed to the water outlet end of the main water pipe 41 through the spray arm support 41. The water outlet end of the main water pipe 41 can be connected to the water inlet 101 of the main spray arm 1 through the spray arm rotating shaft 42, thereby providing driving water to the main spray arm 1 and ensuring that the main spray arm 1 is reliably rotatably connected to the main water pipe 41.

[0054] refer to Figure 1-2 This embodiment also provides a dishwasher, which includes a dish rack assembly 5 and a spray arm mechanism as described above. The spray arm mechanism is detachably installed at the bottom of the dish rack assembly 5. Specifically, the main water pipe 11 is detachably connected to the dish rack assembly 5, and the auxiliary spray arm 2 is detachably connected to the dish rack assembly 5 via a connector (not shown in the figure), thereby enabling the spray arm mechanism to be detachably connected to the bottom of the dish rack assembly 5 via the water pipe 31 and the connector. During the dishwasher's cleaning process, the main spray arm 1 rotates under the action of water flow and sprays the dishes in the dish rack assembly 5. When the main spray arm 1 rotates, it is linked to the swing of the auxiliary spray arm 2, so that the auxiliary spray arm 2 focuses on spraying the dishes in the dish rack assembly 5 back and forth, increasing the rinsing angle, enriching the spraying diversity, and effectively improving the cleaning effect of the dishwasher.

[0055] Example 2

[0056] The difference between this embodiment and Embodiment 1 lies in the specific structures of the active and driven parts. In this embodiment, the active part is a closed annular pitch-changing groove 106, which is integrally formed on the top of the upper cover 11 of the main spray arm 1, and the radius of the annular pitch-changing groove 106 gradually increases and then gradually decreases along the first direction. The driven part is a positioning protrusion 232, which is integrally formed on the outer wall of the rotating part 23 of the auxiliary spray arm 2 (see reference). Figure 16 Furthermore, the positioning protrusion 232 is movably inserted into the annular pitch-changing groove 106, thereby enabling the main spray arm 1 to reliably link with the auxiliary spray arm 2 through the cooperation of the positioning protrusion 232 and the annular pitch-changing groove 106. The spray angle range of the auxiliary spray arm 2 is β, which is related to the width of the annular pitch-changing groove 106, the width of the positioning protrusion 232, and the difference between the distance P3Q and the distance P1Q.

[0057] Example 3

[0058] refer to Figure 7-12The difference between this embodiment and Embodiment 1 lies in the specific location of the active part. In this embodiment, the main spray arm 1 includes a spray arm body 13 and a cam 14. The spray arm body 13 has a first flow channel 102, an inlet 101 and multiple first spray holes 103 are provided at the top of the spray arm body 13, and two outlet holes 104 are provided at the left and right ends of the bottom of the spray arm body 13. The cam 14 is fixedly connected to the top of the spray arm body 13 and is located around the inlet 101. An annular variable pitch thread rib 105 is integrally formed on the top of the cam 14 and meshes with the gear 231 on the auxiliary spray arm 2. Thus, through the engagement of the annular variable pitch thread rib 105 on the cam 14 and the gear 231, it is ensured that the main spray arm can synchronously drive the cam 14 to rotate when it rotates, and the cam can link the auxiliary spray arm 2 through the gear 231 when it rotates, so that the auxiliary spray arm 2 swings back and forth around its central axis.

[0059] refer to Figure 11 The cam 14 has an annular variable-pitch thread rib 105. This annular variable-pitch thread rib 105 has a center point Q and four special points, namely P1, P2, P3, and P4. Among them, the radius P1Q < radius P2Q = radius P4Q < radius P3Q. When moving from point P1 through P2 to point P3, the distance (i.e., radius) from point Q gradually increases, while when moving from point P3 through P4 to point P1, the distance (i.e., radius) from point Q gradually decreases. When gear 231 meshes with cam 14, it satisfies the condition that point M0 on gear 231 meshes with point P2 or P4 on cam 14. When point M0 on gear 231 rotates to position M2, gear 231 meshes with P1, at which point the gear is at the innermost side of the annular variable-pitch thread rib 105. When point M0 on gear 231 rotates to position M1, gear 231 meshes with point P3, at which point the gear is at the outermost side of the annular variable-pitch thread rib 105. As the annular variable-pitch thread rib 105 gradually increases in size, the gear 231 rotates from the innermost side to the outermost side; conversely, as the annular variable-pitch thread rib 105 gradually decreases in size, the gear 231 rotates from the outermost side to the innermost side, where the rotation angle between the outermost and innermost sides is β. Therefore, when the main spray arm 1 rotates one revolution, the auxiliary spray arm 2 swings back and forth once, forming a spray angle range of β. During this process, the spray water columns of the main and auxiliary spray arms intersect, increasing the rinsing angle and enriching the spraying methods. Where n = 2 to 12, preferably n = 8 or 10.

[0060] refer to Figure 7-12 The cam 14 is provided with two fixing posts 141 located on the two outer sides of the water inlet 101. The spray arm body 13 is integrally formed with an outwardly extending boss 131 at the position corresponding to the fixing posts 141. The boss 131 and the fixing posts 141 are fastened together by fasteners (such as screws). Of course, it can also be replaced by a snap-fit ​​structure, or by welding or riveting to achieve a stable and reliable installation of the cam 14 on the top of the spray arm body 13.

[0061] An annular support portion 108 extending upward is integrally formed at the center of the cam 14. The interior of the annular support portion 108 is connected to the water inlet 101. This annular support portion 108 is used for the vertical passage of the spray arm pivot 42 on the pivot assembly, and also for reliably supporting the spray arm support 41 on the pivot assembly. See [reference needed] Figure 9 .

[0062] In addition, a clearance portion 142 is provided at the position of the cam 14 corresponding to the first nozzle 103, see [reference]. Figure 10-12 This avoids affecting the water outlet area of ​​the spray arm body 13 due to the setting of the cam 14. And / or two downwardly extending reinforcing ribs 143 are integrally formed at the bottom of the cam 14, with the two reinforcing ribs 143 located on opposite outer sides of the spray arm body 13, thereby strengthening the overall strength of the cam 14 and facilitating the quick pre-positioning of the cam 14 on the spray arm body 13, effectively preventing the cam from rotating or shifting relative to the spray arm body.

[0063] Example 4

[0064] refer to Figure 13-16 The difference between this embodiment and Embodiment 3 lies in the specific structures of the active and driven parts. In this embodiment, the active part is a closed annular variable pitch groove 106, which is integrally formed on the top of the cam 14 of the main spray arm 1. The radius of the annular variable pitch groove 106 gradually increases and then gradually decreases along the first direction. Specifically, the annular variable pitch groove 106 is integrally formed by pressing a portion of the top of the cam 14 downwards, and the bottom of the groove abuts against the spray arm body 13. The driven part is a positioning protrusion 232, which is integrally formed on the outer wall of the rotating part 23 of the auxiliary spray arm 2. The positioning protrusion 232 is movably inserted into the annular variable pitch groove 106, thereby realizing the reliable linkage between the main spray arm 1 and the auxiliary spray arm 2 through the cooperation of the positioning protrusion 232 and the annular variable pitch groove 106. The spray angle range of the auxiliary spray arm 2 is β, which is related to the width of the annular variable pitch groove 106, the width of the positioning protrusion 232, and the difference between the distance P3Q and the distance P1Q.

[0065] refer to Figure 14-16The annular pitch-changing groove 106 has a center point and four special points, P1, P2, P3, and P4, with Q as the center point. Point P1 is located at the innermost side of the cam 14 or the annular pitch-changing groove 106, and point P3 is located at the outermost side of the cam 14 or the annular pitch-changing groove 106. The distance P2Q is equal to the distance P4Q, with P1Q being the smallest and P3Q being the largest. The distance (i.e., radius) from point P1 through P2 to P3 gradually increases with distance from point Q, while the distance (i.e., radius) from point P3 through P4 to P1 gradually decreases with distance from point Q. When the radius of the annular pitch-changing groove 106 on the cam 6 gradually increases, the positioning protrusion 232 on the auxiliary spray arm 2 rotates from the innermost side to the outermost side; when the radius of the annular pitch-changing groove 106 on the cam 14 gradually decreases, the positioning protrusion 232 on the auxiliary spray arm 2 rotates from the outermost side to the innermost side. The outermost and innermost sides form a rotation angle β. Therefore, when the main spray arm 7 rotates one revolution, the auxiliary spray arm 2 swings back and forth once, forming a spray angle range of β.

[0066] The above descriptions are merely some embodiments of this utility model. For those skilled in the art, various modifications and improvements can be made without departing from the inventive concept of this utility model, and all such modifications and improvements fall within the protection scope of this utility model.

Claims

1. A spray arm mechanism, characterized in that, include: The main spray arm (1) has an inlet (101) at the top and an active part located around the inlet (101); The auxiliary spray arm (2) is arranged above the main spray arm (1) and can swing back and forth around its central axis. A driven part is provided at the position of the active part corresponding to the auxiliary spray arm (2). The driven part is connected to the active part in a transmission manner so that the auxiliary spray arm (2) can be driven to swing synchronously when the main spray arm (1) rotates.

2. The spray arm mechanism according to claim 1, characterized in that, The active part is a closed annular variable pitch threaded rib (105), the radius of which gradually increases and then gradually decreases along the first direction; the driven part is a gear (231), which is connected to the annular variable pitch threaded rib (105).

3. The spray arm mechanism according to claim 1, characterized in that, The active part is a closed annular variable pitch groove (106), the radius of which gradually increases and then gradually decreases along the first direction; the driven part is a positioning protrusion (232), which is movably inserted into the annular variable pitch groove (106).

4. A spray arm mechanism according to claim 2 or 3, characterized in that, The main spray arm (1) includes an upper cover (11) and a lower cover (12) fixedly connected to each other. The upper cover (11) and the lower cover (12) enclose each other to form a first flow channel (102). The upper cover (11) is provided with the water inlet (101), a plurality of first spray holes (103) and the active part. The active part is integrally formed on the top of the upper cover (11).

5. A spray arm mechanism according to claim 4, characterized in that, Reinforcing parts are provided on the two opposite outer sides of the water inlet (101). The reinforcing parts include strip connecting ribs (1071) arranged at intervals. The opposite ends of the strip connecting ribs (1071) are integrally formed with the upper cover (11) and the active part, respectively.

6. A spray arm mechanism according to claim 4, characterized in that, An upwardly extending annular support portion (108) is integrally formed around the periphery of the water inlet (101).

7. A spray arm mechanism according to claim 4, characterized in that, The main spray arm (1) includes a spray arm body (13) and a cam (14). The spray arm body (13) has an inlet (101) and a plurality of first spray holes (103) on its top. The cam (14) is fixedly connected to the top of the spray arm body (13) and located around the inlet (101). The active part is integrally formed on the top of the cam (14).

8. A spray arm mechanism according to claim 7, characterized in that, An annular support (108) is provided at the center of the cam (14), and the water inlet (101) is connected to the interior of the annular support (108).

9. A spray arm mechanism according to claim 7, characterized in that, An air-blocking portion (142) is provided at the position of the cam (14) corresponding to the first nozzle (103); and / or two reinforcing ribs (143) extending downward are integrally formed at the bottom of the cam (14), and the two reinforcing ribs (143) are respectively located on the opposite outer sides of the spray arm body (13).

10. A spray arm mechanism according to claim 2 or 3, characterized in that, The auxiliary spray arm (2) includes a first flute spray arm (21) and a rotating component (23). The first flute spray arm (21) is connected to the rotating component (23). A gear (231) or a positioning protrusion (232) is integrally formed on the outer wall of the rotating component (23).

11. A spray arm mechanism according to claim 10, characterized in that, The auxiliary spray arm (2) also includes a second flute spray arm (22), and the first flute spray arm (21) is connected and fixed to the second flute spray arm (22) through the rotating member (23).

12. A dishwasher, characterized in that, It includes a bowl basket assembly (5) and a spray arm mechanism as described in any one of claims 1-11, the spray arm mechanism being detachably mounted on the bottom of the bowl basket assembly (5).

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