JPH11332810A - Dishwasher - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dishwasher which enables washing of tableware without further uneven washing. SOLUTION: A nozzle 43 has a recessed part 51 formed in the surface 16a of an arm 16. Water flowing trough a water passageway 38 in the arm 16 is poured out to the recessed part 51 through a water passing path 53 formed in the bottom surface 52 of the recessed part 51. A rotating shaft 56 rises from the bottom surface 52 almost at the central part of the recessed part 51 to rotatably support a propeller 54 arranged in the recessed part 51. The head part of a screw 55 fixed in a screw hole 57 of the rotating shaft 56 covers the upper end face of the rotating shaft 56 to lock the propeller 54 in the axial direction thereof. The propeller 54 is rotated by water injected from the nozzle 43 to scatter water in multiple directions. The water spreads thoroughly through a washing chamber in a wider range.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a dishwasher for automatically washing and rinsing dishes.

[0002]

2. Description of the Related Art Conventionally, water stored in the bottom of a washing room is pumped up and supplied to an arm, and water is jetted from a plurality of nozzles arranged on the arm to wash dishes set in the washing room. Dishwashers are known.

[0003] Among such dishwashers, there is one disclosed in, for example, JP-A-7-163506. In this conventional method, an inverted conical deflecting member is inserted into a nozzle provided on a rotary arm, and water is jetted from the nozzle in a bowl shape.

[0004]

However, in the above-mentioned conventional method, water can be spread to every corner in the cleaning chamber, but since water is not injected directly above the nozzle, the arm is rotated. However, it is hard to say that water can be sprayed evenly. Therefore, there has been a demand for a device capable of evenly distributing water to every corner of the washing room.

[0005] The present invention has been made in view of such a technical background, and an object of the present invention is to provide a dishwasher capable of washing dishes more evenly.

[0006]

According to a first aspect of the present invention, there is provided a dishwasher having a longitudinal arm rotatably disposed in a washing chamber, and a plurality of arms disposed on the arm. In a dishwasher that sprays water from the nozzles and wash the dishes set in the washing chamber with the spray water, predetermined nozzles among a plurality of nozzles are rotated by the spray water to spray the spray water to various directions. A rotating body for jetting is arranged.

According to the first aspect of the invention, the water jetted from the nozzle is scattered in various directions by the rotating body.
Therefore, since water is evenly distributed over a wide area in the washing room, there is no occurrence of uneven washing after washing the dishes.
In addition, a propeller or a disk-shaped planetary nozzle can be considered as the rotating body rotated by the jet water.

According to a second aspect of the present invention, in the dishwasher according to the first aspect, the nozzle has a concave portion formed on a surface of the arm and a hole disposed on a bottom surface of the concave portion. The water stored in the inside is sprayed from the concave portion to above the arm through the hole.

According to the second aspect of the present invention, if the arm has a recess, a space for accommodating the rotating body is preferably provided. In this case, since the concave portion is formed on the surface of the arm, the rotating body does not protrude upward or downward after the rotating body is housed.

According to a third aspect of the present invention, in the dishwasher according to the second aspect, the rotating body is rotatably housed in the recess, and an upper end of the rotating body is substantially flush with a surface of the arm. It is characterized by having a certain feature.

According to the third aspect of the present invention, when the upper end of the rotating body is housed in the recess substantially flush with the surface of the arm, the center of gravity of the arm does not significantly shift. Therefore, as a result that a load such as a bearing for supporting the arm is not greatly applied, the durability of the arm can be improved. Further, the thickness of the arm does not increase only in the portion of the rotating body.

According to a fourth aspect of the present invention, in the dishwasher according to any one of the first to third aspects, the rotating body is a propeller having a plurality of blades.

According to the fourth aspect of the present invention, since the water is scattered by the propeller, the diffusion width of the water is large. Therefore, water can be more evenly sprayed. Also, by changing the angle of the propeller blades, the range in which water is scattered can be freely changed. Further, even if foreign matter enters the nozzle, the foreign matter can be removed by rotating the propeller. Further, since the rotating body is a propeller, all of the water that provides the propeller with a propulsive force for rotation can be used for cleaning, so that there is no loss of water.

According to a fifth aspect of the present invention, in the dishwasher according to the fourth aspect, the nozzle has a rotating shaft rising from substantially the center of the bottom surface, and the hole is formed around the rotating shaft on the bottom surface. The propeller is arranged and has a hub forming a central portion of the propeller, and the hub is connected to a rotating shaft.

According to the fifth aspect of the invention, if the propeller hub is connected to the rotating shaft rising from the bottom surface of the nozzle, the propeller can be easily arranged.

According to a sixth aspect of the present invention, in the dishwasher according to the fifth aspect, a contact portion with which a lower end of the hub of the propeller can contact is provided at a bottom of the concave portion at a root of the rotating shaft. It is characterized by being carried out.

Since the propeller is formed by injection molding, there is a possibility that the propeller may be eccentric or may be distorted during rotation. For example, when the lower end of the blade of the propeller is substantially flush with the lower end of the hub, the propeller may not rotate as a result of contact with the bottom surface of the recess. According to the present invention, the lower end of the hub comes into contact with the contact portion, so that the blade can be reliably prevented from contacting the surrounding member. It is preferable that the contact portion provided at the root of the rotating shaft be a contact surface that is one step higher than the bottom surface of the concave portion. It is more preferable that the contact surface has a circular shape having a diameter smaller than the outer diameter of the hub. Since the contact surface contacts only a part of the lower end of the hub, the rotation of the propeller is more hindered. Without contacting the periphery of the blade.

[0018]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a right side sectional view showing the internal structure of a dishwasher according to one embodiment of the present invention.

The dishwasher 1 has a box-shaped housing 11 having an opening at the front, an openable door 12 capable of closing the front opening of the housing 11, and a washing room 13 defined within the housing 11. And A dish basket 15 for accommodating and holding tableware 14 as an article to be washed can be put in and out of the washing room 13 through a front opening of the housing 11. FIG. 1 shows a bowl as the tableware 14. In addition, tableware basket 15
An arm 16 for injecting water to the tableware 14 stored in the tableware basket 15 is disposed below and substantially at the center of the bottom of the washing chamber 13. Further, a heater 17 (see FIG. 2) is provided at the bottom of the cleaning chamber 13.

A water supply port 18 is formed on the rear surface of the cleaning chamber 13. A water supply pipe 19 is connected to the water supply port 18, and water sent from the water supply (not shown) through the water supply pipe 19 is supplied into the cleaning chamber 13 through the water supply port 18. The water supplied into the cleaning chamber 13 is stored at the bottom of the cleaning chamber 13 and is heated by the heater 17 (see FIG. 2) to become hot water. In the middle of the water supply pipe 19, the washing room 1
A water supply valve 20 for controlling the supply of water to 3 is provided. The water supply valve 20 is formed of, for example, an electromagnetic valve.

Below the cleaning chamber 13, a pump device 23 is provided. The pump device 23 includes the first pump chamber 21
And housing 2 that partitions second pump chamber 22 inside
3a, a cleaning impeller 27 rotatably provided in the first pump chamber 21, a drain impeller 30 rotatably provided in the second pump chamber 22, and a cleaning impeller 27.
And a pump motor 24 for driving the drain impeller 30.

The washing chamber 13 is provided at the bottom thereof.
A water collecting portion 25 for collecting water in the inside is formed. The water collecting section 25 is connected to the first pump chamber 21 via a connection pipe 26. At the time of washing and rinsing, the pump motor 24 is driven to rotate in a predetermined direction, and the washing impeller 27 provided in the first pump chamber 21 is rotated. Sent to

The water sent to the arm 16 is jetted from nozzles 41 to 48 formed on the surface of the arm 16 and sprayed on the tableware 14 stored in the tableware basket 15. Further, the arm 16 is rotated in one direction (the direction of arrow A in FIG. 2) by the reaction force of the fountain flow at this time, and the fountain flow is evenly blown to the tableware 14 in the tableware basket 15.
Thus, the dirt attached to the tableware 14 is removed, and the tableware 14 is washed.

The water collecting section 25 is also connected to the second pump chamber 22 via a connecting pipe 29. When the washing or rinsing is completed, the pump motor 24 is driven to rotate in the direction opposite to the predetermined direction, and the drainage impeller 30 provided in the second pump chamber 22 is rotated, so that the water is collected in the water collecting section 25. The drained water is discharged to the outside through the drain pipe 31. In addition, when the water in the washing room 13 is collected in the water collecting part 25, the residual vegetables and the like dropped from the tableware 14 are collected in the water collecting part 2.
5 is captured by a filter 28 provided at the top of the filter 5.

The dishwasher 1 has a function of drying the dishes 14, and a blower fan 32 for blowing air into the washing chamber 13 is provided at the rear of the housing 11. The blower fan 32 is driven to drive the housing 1
The air sucked from the suction port 33 formed on the rear surface of the cleaning chamber 13 is sent into the cleaning chamber 13 from the ventilation port 34 formed on the rear surface of the cleaning chamber 13. The sent air is heated by the heater 17 to become hot air, and the tableware 14 is dried.

FIG. 2 is a plan view when the inside of the cleaning chamber 13 is viewed from above. FIG. 3A shows the arm 16.
3A is a plan view when viewed from above, and FIG. 3B is a cross-sectional view taken along a cutting line AA shown in FIG.

Hereinafter, the arm will be described in detail.

Referring to FIGS. 1 to 3, arm 16 is an elongated member extending in the horizontal direction. Upper member 35 and lower member 36 made of, for example, resin are combined with each other, and inside thereof, , A running water channel 38 extending in the longitudinal direction of the arm 16 is formed. The arm 16 is rotatably supported at substantially the center in the longitudinal direction by a cylindrical water supply shaft 37 provided substantially at the bottom of the cleaning chamber 13. The water supply shaft 37 is connected to a discharge port of the first pump chamber 21, and water sent from the first pump chamber 21 is introduced into the flowing water passage 38 through the water supply shaft 37.

A plurality (eight in this embodiment) of nozzles 41 to 48 are arranged on the surface 16a of the arm 16. The water that has flowed into the flowing water channel 38 in the arm 16 is jetted from these nozzles 41 to 48.

The fountain flow spouted from each of the nozzles 41 to 48 will be specifically described.

From the nozzle 41, a direct jet flow having a small jet water diameter is generated substantially vertically upward. The nozzle 42 is formed with two injection ports 49 and 50 which are long in the longitudinal direction of the arm 16.
6, fan-shaped shower fountain flows in two different directions intersecting in the longitudinal direction. The nozzle 44, the nozzle 46, and the nozzle 47 are configured in the same shape as the nozzle 42, and generate fan-shaped shower fountain flows in two different directions intersecting with the longitudinal direction of the arm 16. In addition, a shower fountain flow spreading fanwise upward from the nozzle 45 is generated.

Further, a direct fountain flow is generated from the nozzle 48 obliquely upward and in a direction intersecting the longitudinal direction of the arm 16. The arm 16 is rotated about the water supply shaft 37 in one direction A (see FIG. 2) by the reaction force of the water flow injected from the nozzle 48. That is, the nozzle 48 has a cleaning function of the tableware 14 (see FIG. 1) and the arm 16.
It also has the function of propulsion rotation. Therefore, there is no need to separately provide a propulsion nozzle for rotating the arm 16.

The feature of this embodiment lies in the shape of the nozzle 43.

The nozzle 43 has a concave portion 51 formed on the surface 16 a of the arm 16 and a water hole 53 formed on the bottom surface 52 of the concave portion 51. The water flowing through the water channel 38 in the arm 16 passes through the water hole 53 and passes through the recess 5.
Poured out to one. The recess 51 has a propeller 54
Are rotatably arranged, and the propeller 54 is rotated by water jetted from the nozzle 43. Therefore, the water jetted from the nozzle 43 is scattered in various directions by the propeller 54.

As described above, by using the propeller 54, all of the water that provides the propeller 54 with a propulsive force for rotation can be used for cleaning, so that there is no loss of water. Further, even when foreign matter enters the nozzle 43, the foreign matter can be removed by rotating the propeller 54.

Since the water is scattered by the propeller 54, the diffusion width of the water is large. Therefore, water can be more evenly sprayed into the cleaning chamber 13. The screw 55 prevents the propeller 54 from coming off the nozzle 43.

FIG. 4A is a plan view of a main part of the arm with the propeller removed, and FIG.
It is sectional drawing at the time of cutting | disconnection along the cutting line BB shown to (a).

The concave portion 51 of the nozzle 43 has a substantially truncated cone shape that opens upward. Also, the concave portion 51
The propeller 54 is rotatably supported (maintenance,
A rotating shaft 56 for locking is raised from the bottom surface 52, and the water passage hole 53 is formed on the back surface around the rotating shaft 56.

The water passage holes 53 are opened at two positions on the bottom surface 52 in a substantially C shape.

The rotating shaft 56 rises from the bottom surface 52 at substantially the center of the recess 51. A screw hole 57 for screwing is formed in the axis of the rotating shaft 56 from above. The screw hole 57 does not communicate with the flowing water channel 38. Next, the propeller 54 will be described with reference to FIG. FIG. 5A is a plan view of the propeller, and FIG. 5B is a side view of the propeller. The propeller 54 is formed of, for example, a resin, and has a hub 59 forming a central portion, and a plurality of (four in this embodiment) blades 60 extending outward from an outer peripheral edge 59b of the hub 59.
And The hub 59 has a hollow cylindrical shape. Each blade 60 extends from the hub 59 in a state of being inclined by about 40 ° with respect to the rotation axis 56. The lower end 60 a of the blade 60 is flush with the lower end 59 a of the hub 59, and the upper end 60 b of the blade 60 is provided to protrude from the hub 59.

FIG. 6 is a cross-sectional view taken along a cutting line CC shown in FIG. 3A in a state where the propeller 54 is arranged in the concave portion 51. The screw 55 is fixed to the screw hole 57, and the head of the screw 55 covers the upper end surface of the rotating shaft 56. The head of the screw 55 is larger than the inner diameter Da of the hub 59 (see FIG. 5B), so that the propeller 54 is prevented from coming off in the axial direction.

The propeller 54 has a hollow cylindrical hub 59 fitted in the rotary shaft 56 and is disposed in the recess 51. With the propeller 54 disposed in the recess 51, the upper end of the propeller 54, that is, the upper end 60 b of the blade 60, is substantially flush with the surface 16 a of the arm 16. As described above, since the propeller 54 is housed in the concave portion 51 formed on the surface 16a of the arm 16, the propeller 54 does not protrude above and to the side of the arm 16, so that the propeller 54 I won't be scratched.

Also, as in this embodiment, the propeller 5
If the upper end of 4 is substantially flush with the surface 16a of the arm 16,
Since the center of gravity of the arm 16 does not significantly shift, the load on the members such as the bearings that support the arm 16 is not increased, so that the durability of the arm 16 can be improved. Further, the thickness of the arm 16 does not increase only at the propeller 54.

The inner diameter Da of the hub 59 (see FIG. 5 (b)) is slightly larger than the outer diameter Db of the rotary shaft 56 (see FIG. 4 (b)).
(See FIG. 5B). The height Ha of the rotating shaft 56 (see FIG.
(See (b))). Therefore, the propeller 54 can be smoothly rotated without any backlash with the rotating shaft 56.

Incidentally, since the propeller 54 is formed by injection molding, eccentricity may occur or the propeller 54 may be distorted during rotation. In such a case, the lower end 60a is connected to the lower end 59a of the hub 59.
As a result, the blade 60 of the propeller 54, which is substantially flush with the bottom surface, comes into contact with the bottom surface 52 of the concave portion 51, so that the propeller 54 may not rotate. Therefore, as shown in FIGS. 5 and 6, a contact surface 58 is formed at the base of the rotating shaft 56 as a contact portion that is one step higher than the bottom surface 52 of the concave portion 51. Hub 59 of propeller 54 to be arranged
Can be brought into contact with the lower end 59a. This contact surface 58
Has a circular shape concentric with the rotating shaft 56, and has a diameter smaller than the outer diameter of the hub 59. As described above, since the lower end 59a of the hub 59 comes into contact with the contact surface 58 raised one step, the blade 60 of the propeller 54 whose lower end 60a is substantially flush with the lower end 59a of the hub 59 collides with the surrounding member. Can be reliably prevented.

Since the contact surface 58 has a circular shape having a diameter smaller than the outer diameter of the hub 59, the contact surface 5
The rotation of the propeller 54 is not hindered because the portion 8 contacts only a part of the lower end 59a of the hub 59.

When the propeller 54 is formed so that the lower end 59a of the hub 59 is lower than the lower end 60a of the blade 60, it is possible to reliably prevent the propeller 54 from hitting the surrounding members of the blade 60.

In this embodiment, through the water hole 53,
When the water blows out to the concave portion 51, the propeller 54 rotates about the rotation shaft 56 by the force of the water, and at the same time, the blades 60 of the propeller 54 scatter the water in various directions, and the water is jetted. Therefore, the water injected from the nozzle 43 is
Since the water is scattered in various directions by the propeller 54, the water is evenly distributed over a wide area in the washing room 13, and as a result, there is no unevenness in washing after washing the dishes.

In this embodiment, the blades 60 of the propeller 54 extend from the hub 59 in a state of being inclined by about 40 ° with respect to the rotation shaft 56. However, the angle of the blades 60 is changed. Thus, the range in which water is scattered can be freely changed.

The nozzle 4 which is a feature of this embodiment is
3 may be attached to any position of the arm 16. Further, the nozzle 43, which is a feature of this embodiment,
Is one of the eight nozzles of the arm 16, but is not limited to this, and a plurality of nozzles may be provided, or all of the nozzles may be used.

FIG. 7A is a plan view showing a main part of an arm according to another embodiment of the present invention, and FIG.
FIG. 8 is a cross-sectional view taken along a cutting line DD shown in FIG. At a predetermined nozzle 61 among a plurality of nozzles of the long arm 16, a rotating body 62 that is rotated by the spray water and sprays the spray water to various directions is disposed. It is rotatably engaged. The rotating body 62 has a hollow disk shape and is disposed in a concave portion 63 formed on the surface 16 a of the arm 16. The upper surface 62 a of the rotating body 62 is substantially flush with the surface 16 a of the arm 16. It has become.

As described above, since the rotating body 62 is housed in the concave portion 51 formed on the surface 16a of the arm 16,
As a result of the rotating body 62 not protruding above and to the side of the arm 16, the rotating body 62 does not catch on, for example, the tableware basket 15. Further, as in this embodiment, if the upper surface 62a of the rotating body 62 is substantially flush with the surface 16a of the arm 16, the center of gravity of the arm 16 does not significantly shift. As a result, the load on the members is not large, so that the durability of the arm 16 can be improved. Further, the thickness of the arm 16 does not increase only in the portion of the rotating body 62.

The nozzle 61 has a concave portion 63 formed on the surface 16a of the arm 16 and a water passage hole 65 formed on the bottom surface 64 of the concave portion 63. The recess 63 has a cylindrical shape having a diameter substantially the same as the width of the long arm 16 at this position.

The water passage hole 65 is formed by the water passage hole 53 of the above embodiment.
Similarly to the above, it communicates with the flowing water channel 38 to send the water stored in the arm 16 to the concave portion 63. The water passage hole 65 is formed in a substantially circular shape substantially in the center of the bottom surface 64 of the concave portion 63.

The rotating body 62 has two injection ports 66 and 67 on the upper surface 62a. A substantially circular opening 6 corresponding to the water passage hole 65 is provided on the bottom surface 62b of the rotating body 62.
9 is formed, and the water sent out from the water hole 65 to the concave portion 63 is sent to the injection ports 66 and 67 through the opening 69. The rotating body 62 has two rotating shaft pieces 70, 70 extending upward from the peripheral edge of the opening 69, and a projection formed by projecting the two rotating shaft pieces 70, 70 outward in the middle thereof. It is prevented from falling off by the parts 71, 71.
The rotating body 62 is rotatably supported by the arm 16 in a state in which the rotation of the rotating body 62 has been achieved by the protrusions 71, 71 being engaged with the back surface of the recess 63. Rotating shaft piece 70,
Reference numeral 70 denotes a pair of opposed members, and the pair of rotating shaft pieces 70, 70 serves as a rotating shaft of the rotating body 62.

The two injection ports 66 and 67 of the rotating body 62
It has a different shape, so that a fountain flow in two different directions is generated from the rotating body 62. A shower fountain flow spreading fan-shaped upward is generated from the injection port 66, and a shower fountain flow is generated diagonally upward in the opposite direction to the rotation direction A of the arm 16 from the other injection port 67. . Since the shower fountain flow is generated obliquely upward from the injection port 67 in the direction opposite to the direction A, the rotating body 62 can be more easily rotated. Therefore, water can be spread more evenly. In the dishwasher according to this embodiment, the water is jetted from the two jet ports 66 and 67 while the rotating body 62 rotates, so that the jet is jetted to various directions. Therefore, the water is evenly distributed over a wide area in the washing room 13, so that no washing unevenness occurs after washing the dishes.

Although the description of the embodiment of the present invention is as described above, the present invention is not limited to the above-described embodiment, and various modifications may be made within the scope described in the claims. Is possible.

[0059]

According to the first aspect of the present invention, the water jetted from the nozzle is dispersed in various directions by the rotating body. Therefore, since water is evenly distributed over a wide area in the washing room, there is no occurrence of uneven washing after washing the dishes.

According to the second aspect of the present invention, it is preferable that a recess is formed in the arm since a space for accommodating the rotating body is provided. In this case, since the concave portion is formed on the surface of the arm, the rotating body does not protrude upward or downward after the rotating body is housed.

According to the third aspect of the present invention, when the upper end of the rotating body is housed in the recess substantially flush with the surface of the arm, the center of gravity of the arm does not significantly shift. Therefore, as a result that a load such as a bearing for supporting the arm is not greatly applied, the durability of the arm can be improved. Further, the thickness of the arm does not increase only in the portion of the rotating body.

According to the fourth aspect of the present invention, since the water is scattered by the propeller, the diffusion width of the water is large. Therefore, water can be more evenly sprayed. Further, by changing the setting of the angle of the blade of the propeller, the range in which water is scattered can be freely changed. Furthermore, even if foreign matter enters the nozzle, for example,
Foreign matter can be removed by rotating the propeller.
Furthermore, since the rotating body is a propeller, and all the water that gives the propeller a propulsive force for rotation can be used for cleaning, there is no loss of water.

According to the fifth aspect of the invention, if the propeller hub is connected to the rotating shaft rising from the bottom surface of the nozzle, the propeller can be easily arranged.

According to the sixth aspect of the present invention, the propeller formed by injection molding is eccentric during rotation,
Even in the case where distortion occurs, the lower end of the hub abuts on the abutting portion, thereby reliably preventing the blade from colliding with the surrounding member.

[Brief description of the drawings]

FIG. 1 is a right side sectional view showing an internal configuration of a dishwasher according to an embodiment of the present invention.

FIG. 2 is a plan view when the cleaning chamber is viewed from above.

FIG. 3 is a view showing an arm.

FIG. 4 is a diagram showing a main part of the arm with a propeller removed.

FIG. 5 is a diagram showing a propeller.

FIG. 6A shows a state in which a propeller is arranged in a recess.
It is sectional drawing when it cut | disconnects along the cutting line CC shown in FIG.

FIG. 7 is a diagram showing a main part of an arm according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Housing 14 Tableware 16 Arm 17 Heater 18 Water supply port 38 Flowing water channel 41-48,61 Nozzle 49,50 Injection port 51,63 Depression 52,64 Bottom surface 53,65 Water flow hole 54 Propeller 56 Rotating shaft 58 Contact surface (Contact part) 59 hub 60 blade 60a lower end 62 rotating body 62a upper surface 65 water hole 66, 67 injection port 70 rotary shaft piece

Claims (6)

[Claims] 1. A washing machine comprising a longitudinal arm rotatably arranged in a washing chamber, wherein water is jetted from a plurality of nozzles arranged on the arm, and the tableware set in the washing chamber is sprayed by the jetted water. A dishwasher for washing, characterized in that a rotating body, which is rotated by the spray water and sprays the spray water to various directions, is disposed at a predetermined nozzle among the plurality of nozzles. 2. The nozzle has a concave portion formed on the surface of the arm and a hole provided on the bottom surface of the concave portion, and water retained in the arm passes through the hole to form the concave portion. The dishwasher according to claim 1, wherein the dishwasher is sprayed from above the arm. 3. The dishwasher according to claim 2, wherein the rotating body is rotatably accommodated in the recess, and an upper end of the rotating body is substantially flush with a surface of the arm. 4. The dishwasher according to claim 1, wherein the rotating body is a propeller having a plurality of blades. 5. The nozzle has a rotating shaft rising from substantially the center of the bottom surface, the hole is disposed around the rotating shaft on the bottom surface, and the propeller forms a central portion of the propeller. 5. The dishwasher according to claim 4, further comprising a hub that is connected to the rotating shaft. 6. A dishwasher according to claim 5, wherein a contact portion is provided at a bottom of said concave portion at a root of said rotary shaft, said contact portion being capable of contacting a lower end of said hub of said propeller. .