JP2548490B2 - Dishwasher - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention mainly relates to an improvement of a commercial dishwasher for washing a large amount of dishes such as hotels, restaurants, hospitals and school facilities.

[0002]

2. Description of the Related Art In recent years, due to the popularization of hygiene and rising labor costs, conventional hand-washing with a sink and mechanized washing with a dishwasher are becoming popular. Especially in facilities that wash large amounts of dishes such as hotels, restaurants, hospitals, and school facilities, a reasonable and economical dishwashing process is constantly operated, so a highly efficient and more compact dishwasher It is required to be introduced.

[0003]

As a conventional dishwasher for business use of this type, an under-counter type that is stored under a cooking table, a door type that is independently installed on the floor like a refrigerator, and a washing and rinsing There is a net conveyor type in which a large amount of tableware is washed by continuously drying on a linear conveyor. Especially, in the latter, a large dishwasher consumes a large amount of energy for washing, rinsing, drying and transferring dishes, and a large number of facilities such as a plurality of pump motors are required.

As one attempt to save energy and volume of a dishwasher, it has been considered to use a pump motor commonly used separately for washing and rinsing. One of them is, for example, as shown in Japanese Patent Laid-Open No. 55-155626, in which cleaning water containing detergent is first sent to a water pump, and then clean water containing no detergent is sent to the same pump as rinsing water, or cleaning water. It was conceivable that the piping of No. 1 and the piping of rinsing water were switched by a solenoid valve and alternately sent to the pump, but the conversion from washing to rinsing was not sufficient, and it was not particularly useful for commercial use.

Next, it was considered that the pumps mounted on the left and right of the coaxial motor could selectively supply the washing water and the rinsing water to the washing machine through the butterfly valve. In this case, it is not preferable to drive both pumps at the same time from the viewpoint of energy saving, so it is necessary to appropriately shut off the motor shaft and the pump. For this reason, a one-way clutch at both ends of the motor shaft,
By providing a clutch mechanism such as a centrifugal clutch and an electromagnetic clutch,
It was considered to drive the pump selectively to the motor,
The mechanism such as the bearing arrangement becomes complicated and becomes oblong, and especially the solenoid valve, the solenoid clutch and the like are expensive, and the intended purpose cannot be achieved.

The present invention has improved the above-mentioned drawbacks, and in the dishwasher, one motor is used to selectively send washing water and rinsing water to the dishwashing section, which is a resource-saving and energy-saving dishwasher. Aim to get.

[0007]

In order to solve the above-mentioned problems, the present invention has a pump impeller attached to each shaft of a biaxial motor capable of rotating in the forward and reverse directions, and suction pipes are respectively provided in pump housings surrounding the respective impellers. And a discharge pipe, and the other end of each discharge pipe is connected to a dishwashing tank, a screw thread in the same direction is provided at each shaft end of the both-axis motor, and the blade is attached to a bearing of the impeller. A screw groove that engages with the screw thread is cut so that the vehicle can reciprocate a certain distance in the axial direction as the shaft rotates in the pump housing that surrounds it. The pump impeller has a short cylindrical liner ring attached to the front part in the axial direction from the spiral impeller, and the liner ring is tightly fitted so as not to hinder the rotation of the liner ring and the impeller when the impeller moves in the axial tip direction. And the suction pipe connects the impeller Pumping a short cylindrical wear ring that is connected to the discharge pipe and creates a gap between the liner ring and the suction pipe and the discharge pipe when the impeller moves in the motor direction.・ Regarding the dishwasher attached to the joint between the housing and the suction pipe, the impeller on one side moves in the motor direction and the impeller on the other side moves in the axial end direction as the motor rotates in one direction. Is housed in the housing.

The impeller is of a normal axial suction type and a centrifugal discharge type (commonly known as a spiral type), and in particular, the bearing portion is provided with a thread groove to be screwed with the thread of the motor shaft, and reciprocates a fixed distance in the axial direction. It is possible. An impeller nut is fixed to each shaft end of the double shaft motor, and a mechanical seal retainer is provided on a bearing portion of a pump housing surrounding the impeller. The impeller is axially arranged between the impeller nut and the mechanical seal retainer. It can be reciprocated.

A pump impeller attached to each shaft of a double-shaft motor has a short cylindrical liner ring attached to the tip of a spiral vane, and when the impeller moves in the axial tip direction, the liner ring fits almost closely with the liner ring. In addition, a short cylindrical wear ring is attached to the joint between the pump housing and the suction pipe so that when the impeller moves toward the motor, a gap is formed between the impeller and the liner ring.

The pump housing is provided with a suction port and a discharge port, respectively, and each suction port is connected to a washing water supply pipe and a rinsing water supply pipe, respectively, and each discharge port communicates with a dish washing tank.

If an overflow type (commonly known as a cascade pump) or a volumetric pump for viscous liquid is used as the impeller instead of the centrifugal discharge type, the impeller does not need to move in the axial direction. Is low efficiency, high pressure, not suitable for dishwasher.

[0012]

When the double shaft motor rotates in the forward direction, one of the impellers moves in the shaft end direction in the housing by the screw of the shaft and the like, and a short cylindrical liner ring is pumped forward from the spiral blade part in the axial direction.・ Short cylindrical wear ring attached to the joint between the housing and the suction pipe, and tightly fitted so as not to hinder the rotation of the impeller, then fixed to the shaft and rotated, and sucked into the housing from the suction port. The cleaning liquid is urged and sent from the discharge port toward the dish washing tank.

At this time, the impeller of the same type, which is symmetrically attached to the other end of the motor shaft, moves in the motor direction in the housing by the screw of the shaft in accordance with the rotation of the shaft, and then is fixed to the shaft and rotates. . In this case, a gap is formed in the housing between the impeller and the suction port, and the liquid once discharged from the impeller circulates in the housing and returns to the impeller again. Simply stirring the liquid does not act as a pump and therefore rinse water is not pumped from the outlet towards the dishwasher.

When the double shaft motor is switched to the reverse rotation at the stage where the washing process in the dish washing tank is completed, the impeller on the washing water side is attracted to the motor side and then only stirs to discharge the washing water. After stopping, the impeller on the rinse water side starts acting as a pump after moving to the shaft end, and discharges the biased rinse water toward the dish washing tank.

The dishwasher according to the present invention uses the above-described biaxial motor with impellers capable of rotating in the forward and reverse directions to alternately perform dishwashing and rinsing with a single power source. The process is not limited to the process, and it can be used for other processes of dishwashing. in this case,
The capacity of each impeller is set to an optimum value according to the capacity of the liquid to be sent, and the left and right are not necessarily the same size.

[0016]

EXAMPLES Examples will be described with reference to the drawings.
As shown in FIG. 1, impellers 2 and 2'of a centrifugal pump are provided on both ends of a biaxial motor 1 capable of rotating in the forward and reverse directions, screw threads 4 and 4'implanted on motor shafts 3 and 3 ', and impeller bearings. By fitting with the thread groove cut into the inner surface, the hoop housing 5, 5'which encloses the impeller is mounted so as to be movable in the axial direction by a predetermined distance. To the housings 5 and 5 ', suction pipes 6 and 6'for washing water or rinsing water are connected from the outside in the axial direction, and discharge pipes 7 and 7'for these liquids are connected in the centrifugal direction.

As shown in FIG. 2, the impellers 2 and 2'are ordinary spiral pump impellers in which a large number of involute curved blades are formed between two disks, and in particular, the inner surface of the bearing has a shaft. Screw grooves 8, 8'to be fitted with the screw portions 4, 4'of
Is provided, and the portion of the housing facing the suction port is
As shown in FIG. 3, liner rings 9, 9'are formed. When the impellers 2 and 2'are attached to the shaft of the motor 1, mechanical seal retainers 10 and 10 'are provided on the housing bearing portion and the motor shaft tip portion is provided on the housing bearing portion in order to regulate the axial movement of the impeller. Impeller nuts 11 and 11 'are fixed to the shafts, respectively.

FIG. 3 shows the state of the impeller when the double-shaft motor 1 rotates forward (counterclockwise when viewed from the suction port on the right side of the drawing), and when it rotates in the reverse direction (clockwise when viewed from the suction port on the right side of the drawing). Fig. 4 shows the state of the impeller.

In FIG. 3, the impeller 2 moves to the tip of the shaft by the screw thread 4 of the shaft 3 as the shaft rotates, contacts the inner surface of the nut 11, and then rotates together with the shaft 3. In this case, since the liner ring 9 of the impeller 2 is almost closely fitted to the wear ring 12 provided at the joint between the suction pipe 6 and the housing 5, the liquid sucked from the suction pipe 6 into the housing 5 is almost The entire volume is pressurized via the impeller 2 and the discharge pipe 7
Is discharged from the dish washing tank 13 (see FIG. 1).

Next, when the two-shaft motor 1 is rotated in the reverse direction, the impeller 2 moves in the motor direction by the thread 4 of the shaft 3 as shown in FIG.
And then rotates with the shaft 3. In this case impeller 2
The liner ring 9 is released from the fitted state of the suction pipe 6 with the wear ring 12, and a large annular gap is formed between the liner ring 9 and the wear ring 12.

The impeller 2 rotates as a pump, but since the impeller 2 is rotating in the opposite direction to the action of the involute curve of the vanes, the action is reduced to about 1/3 of the normal rotation. Therefore, the flow of the liquid discharged from the impeller 2 is as shown in FIG.
As shown in FIG. 3, the flow is circulated in the housing 5, and the impeller 2 is again passed through the gap between the liner ring 9 and the wear ring 12.
As a result, the liquid is sucked into the circulation pipe, and the liquid from the suction pipe 6 is not discharged from the discharge pipe 7. In this case, the impeller 2'provided on the opposite side of the two-axis motor 1 is rotating in the normal direction, and another liquid, for example, rinse water is discharged toward the dish washing tank.

[0022]

Since the present invention is configured as described above, 1
Pump impellers attached to both shafts of each motor are selectively operated by the forward and reverse rotations of the motors, and wash water, rinsing water or other liquid necessary for dish washing are alternately sent to the dish washing tank. Therefore, it is possible to operate one dishwasher which has conventionally required a plurality of motors by one to half, and the capacity and size of the dishwasher can be significantly reduced.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a dishwasher equipped with a double shaft motor according to the present invention.

FIG. 2 is a sketch drawing of a pump impeller according to the present invention.

FIG. 3 is a cross-sectional view of a state in which the impeller moves in the axial end direction by the positive rotation of the biaxial motor.

FIG. 4 is a cross-sectional view of a state in which the impeller moves in the motor direction by the reverse rotation of the biaxial motor.

[Explanation of symbols]

 1 double shaft motor 2, 2'impeller 3, 3'motor shaft 4, 4 'screw thread 5, 5' pump housing 6, 6'suction pipe 7, 7 'discharge pipe 8, 8' screw groove 9, 9 'Liner ring 10, 10' Mechanical seal retainer 11, 11 'Impeller nut 12 Wear ring 13 Dishwash tank

Claims (2)

(57) [Claims] 1. A pump impeller is attached to each shaft of a two-axis motor capable of rotating in the normal and reverse directions, a suction pipe and a discharge pipe are attached to a pump housing surrounding each impeller, and the other end of each discharge pipe is a tableware. In a dishwasher connected to a washing tank, a screw thread in the same direction is provided at each shaft end of the both shaft motors, and a bearing of the impeller is rotated by the shaft in a pump housing surrounding the impeller. A screw groove that engages with the screw thread is cut so that it can reciprocate in the axial direction by a certain distance, and the pump impeller attached to each shaft of the two-shaft motor is shorter in the axial front part than the spiral blade part. A cylindrical liner ring is attached, and when the impeller moves in the axial tip direction, the liner ring and the impeller are tightly fitted so as not to hinder the rotation of the impeller so that the suction pipe passes through the impeller. Connected to the discharge pipe and the impeller moves At the joint between the pump housing and the suction tube, a short cylindrical wear ring that creates a gap between the liner ring and the liner ring to disconnect the suction tube from the discharge tube. A dishwasher characterized by being installed. 2. An impeller nut is fixed to each shaft end of a double shaft motor, and a mechanical seal retainer is provided on a bearing portion of a pump housing surrounding the impeller. The impeller has the impeller nut and the mechanical seal retainer. The dishwasher according to claim 1, wherein the dishwasher is capable of reciprocating in the axial direction.