JPH1118948A - Centrifugal pump for electric water boiler - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a centrifugal pump for electric water boiler in which a motor can be fixed without using a screw and easily assembled, and the replacement of the motor can be extremely easily performed. SOLUTION: In this centrifugal pump, the dimension from the end surface of a motor support part 17 to the inside of a contact piece 20 is set to substantially the same as the length of the body part of a motor 11, so that the motor support part 17 and the contact piece 20 can make contact with an output shaft side end surface 11a and an anti-output shaft side end surface 11b, respectively, to support the motor 11 in the longitudinal direction, and the motor 11 can be thus fixed without using a screw. In disassembling, the motor 11 can be taken out by releasing a screw 19 to remove a case 14, and the disassembling is extremely facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a small centrifugal pump used in an electric water heater or the like.

[0002]

2. Description of the Related Art Conventionally, in such a centrifugal pump for an electric water heater, as shown in FIG. 11, a motor 1 is fixed to a motor holder 2 with a screw 4 through a hole 3 provided in the motor holder 2. Reference numeral 5 denotes a driving magnet mounted on the output shaft 6 of the motor 1 by press fitting. The driving magnet 5 needs a certain outer diameter to magnetically couple the impeller 8 contained in the case 7. The screw 4 is hidden from the magnet 5.

[0003]

However, in the above-described conventional configuration, when the motor is disengaged, since the driving magnet hides the screw, the press-fitted driving magnet is pulled out. The screws had to be removed afterwards, and the replacement work was troublesome. Furthermore, the output shaft may be bent when the drive magnet is pulled out, and the motor may become unusable. Further, when the driving magnet cannot be pulled out, the entire motor holder has to be discarded.

An object of the present invention is to solve such a conventional problem and to provide a centrifugal pump for an electric water heater that can be easily assembled and the motor can be replaced very easily.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is such that a motor is supported in a longitudinal direction by a motor supporting portion provided on a case and a contact piece of a motor holder. In addition, since the motor is held without using screws, the motor can be replaced very easily.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a motor supporting apparatus according to a first embodiment of the present invention; FIG. Since the motor is held without using screws, the motor can be replaced very easily.

Further, according to the present invention, the contact piece is formed in a beam shape to have an elastic force in the longitudinal direction of the motor, so that the motor can be securely held even if the length of the motor slightly varies. can do.

Further, according to the third aspect of the present invention, the contact piece is divided in the radial direction, so that the motor can be removed even if the motor has a lead wire or the like. Also, the lead wires can be attached to the motor before being assembled.

Further, in the invention according to claim 4, the contact piece is L
By using the mold, the entire L-shaped portion is bent when a force is applied to the contact piece, and deformation and the like can be prevented as compared with the case where only the portion that is in contact with the end face on the non-output side is bent.

According to the fifth aspect of the present invention, the inner diameter of the contact portion of the motor holder is made substantially the same as the outer periphery of the motor, and the inner diameter is gradually increased toward the case side. The motor can be easily inserted from the part, and when the part which comes into contact with the contact piece is inserted, the inner diameter and the outer periphery of the motor are almost the same, so that the motor can be held tightly.

Further, according to the present invention, the clearance between the rib, which is one step higher than the motor supporting portion, and the outer periphery of the motor is made smaller than the space between the driving magnet and the inner diameter of the motor supporting portion. Even when the motor is dropped and a radial force is applied to the motor, the ribs and the motor do not come into contact with each other and the drive magnet and the inner diameter of the motor support portion do not come into contact with each other, so that the output shaft is not deformed.

According to the seventh aspect of the present invention, the motor holder is provided with a mounting portion to the electric water heater main body, and the case is floated from the main body, so that heat transmitted from the main body to the seal portion of the case is reduced, and the sealing performance is improved. Can be stabilized. In addition, since there is no extra part such as a mounting portion of the main body in the case, it does not become a hindrance when assembling the case.

According to the present invention, the height of the convex portion for fitting the motor is made higher than the height of the pin for fitting the case, so that when the mounting direction of the motor is wrong, the pin and the hole are formed. Since they are not fitted and become unstable, they are not mistakenly assembled and mistakenly assembled.

[0014]

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

(Embodiment 1) In FIG. 1 and FIG.
Reference numeral 1 denotes a motor, and a driving magnet 13 having a diameter smaller than the outer diameter of the motor is press-fitted into an output shaft 12 of the motor 11. Reference numeral 14 denotes a case integrated with the partition 14a by ultrasonic welding or the like.
The impeller 15 magnetically coupled via a is housed. A shaft 16 supports the impeller 15, and the shaft 16 is semi-fixed to the case 14. The case 14 is provided with a suction port 14b and a discharge port 14c.
Hot water is sucked and discharged by the rotation of 5. Partition wall 1
4 a is provided with a cylindrical motor support portion 17 which is in contact with the output shaft side end surface 11 a of the motor 11 and has an inner diameter larger than the diameter of the driving magnet 13.

The motor 11 is covered with a motor holder 18, and the motor holder 18 is fastened to the case 14 by screws 19. Reference numeral 20 denotes a contact piece that is provided on the motor holder 18 and that comes into contact with the end surface 11b on the side opposite to the output shaft of the motor 11. The dimension from the end face of the motor support portion 17 to the inside of the contact piece 20 is almost the same as the length of the body of the motor 11. When the motor holder 18 and the case 14 are fastened with the screw 19, the motor 11 is moved in the length direction. Supported and fixed.

Reference numeral 21 denotes a container of the electric kettle main body provided with a heater at the bottom. Reference numeral 22 denotes a heat shield plate that blocks heat from the heater of the container 21.
The above-described pump is attached to the heat shield plate 22.
The suction port 14b is a pipe 2 provided at the bottom of the container 21.
1b through a packing 23 and the motor 1
When electricity is supplied to 1, the hot water in the container 21 is sucked into the case 14 and discharged toward the outlet 24 side.

In the above-described configuration, when the motor 11 is assembled, first, the motor 11 is placed in the motor holder 18.
And cover the case 14 and fasten the motor holder 18 and the case 14 with screws 19. Then, the dimension from the end surface of the motor support portion 17 to the inside of the contact piece 20 is changed to the size of the motor 11.
Since the length of the body portion is substantially the same, the motor supporting portion 17 abuts on the output shaft side end surface 11a and the contact piece 20 abuts on the non-output shaft side end surface 11b, and the motor 11 is supported in the length direction.
It can be fixed without using screws. Also, when disassembling, the motor 11 can be taken out by removing the screw 19 and removing the case 14, and the disassembly can be done very easily.

(Embodiment 2) In FIG.
The contact piece 20 is cut off by cutting a part of the bottom 18a of
The abutment piece 20 has an elastic force, being independent of b. Therefore, even if the length of the motor 11 varies and becomes longer, the contact piece 20 bends, so that the motor 11 can be incorporated without applying an excessive force. Conversely, the motor 11
When the length of the motor 11 is short, the motor 11
Can be pressed against the motor support portion 17 and assembled without rattling.

(Embodiment 3) In FIG. 4, the end surface 1 on the side opposite to the output shaft is shown.
Two electrical connection terminals 25 are attached to 1b so as to sandwich the contact piece 20, and a lead wire 26 is fixed to the electrical connection terminal 25 by soldering or the like. And
The abutment piece 20 is divided at a beam-shaped central portion.
Accordingly, even when the assembled motor 11 with the lead wire 26 is taken out, the motor 11 with the lead wire 26 can be disassembled by passing the lead wire 26 through the divided portion of the contact piece 20 without removing the fixed lead wire 26. Also, even when the lead wire 26 is attached to the motor 11 first, the assembly can be performed by passing the lead wire 26 through the divided portion of the contact piece 20.

(Embodiment 4) In FIG.
The contact piece 20 is formed in an L-shape by cutting out the cylindrical portion 18b of No. 8. Therefore, when an unreasonable force is applied to the contact piece 20, the entire L-shaped portion bends, and deformation and the like can be prevented as compared with the case where only the portion contacting the non-output side end surface 11b bends.

(Embodiment 5) In FIG.
The inner diameter of the contact piece 20 is substantially the same as the outer circumference of the motor, and the inner diameter is gradually increased toward the case 14 therefrom. Therefore, when assembling, the motor 11 can be easily inserted from a portion having a large diameter. We can hold tightly.

(Embodiment 6) Referring to FIG.
The raised rib 27 is provided with a gap 28 from the outer periphery of the motor 11 so that the position of the motor 11 can be adjusted with respect to the case 14. The gap 28 is smaller than the space 29 between the driving magnet 13 and the inner diameter of the motor support 17. Therefore, for example, the pump 1
Even when a radial force is applied to the motor 1, the rib 27 and the motor 11 hit first, and the driving magnet 13 and the motor support 1
There is no possibility that the output shaft 12 is deformed because the inner diameter does not come into contact with the inner diameter.

(Embodiment 7) In FIGS. 8 and 9, the motor holder 18 is provided with a mounting portion 30 to the heat shield plate 22,
The case 14 is smaller than the motor holder 18 and is mounted so as to float from the heat shield plate 22. Therefore, the heat transmitted from the heat shield plate 22, which becomes high in temperature at the time of boiling water, to the sealing portion of the case 14 can be reduced to prevent deterioration of the sealing portion and to stabilize the sealing performance. In addition, since there is no extra portion such as a mounting portion of the heat shield plate 22 in the case 14, there is no obstacle when assembling and welding the case 14, and the welding can be stabilized.

(Embodiment 8) In FIG. 10, a projection 31 is provided on the motor 11 side of the contact piece 20, and the projection 31 fits into a recess 32 provided on the end face 11b on the side opposite to the output shaft. ing. Further, a pin 33 is provided on the end surface of the motor holder 18 on the case 14 side, and the pin 33 fits into a hole 34 provided in the case 14. And the convex part 31
Is higher than the height of the pin 33, and if the mounting direction of the motor is wrong, the opposite end surface 11b
Does not get on the pin 33, and as a result, the pin 33 and the hole 34 do not fit each other and become unstable, so that a mistake is not noticed, and the pin 33 and the hole 34 are not assembled.

[0026]

As is apparent from the above description of the embodiment, according to the first aspect of the present invention, the motor is supported in the longitudinal direction by the contact portion of the motor holder and the motor holder provided in the case. This makes it easy to assemble and replaces the motor very easily since the motor is held without using screws.

According to the second aspect of the present invention, the contact piece is formed in a beam shape to have an elastic force in the longitudinal direction of the motor, so that the motor can be reliably secured even if the length of the motor slightly varies. Can be held.

Furthermore, according to the third aspect of the present invention, the contact piece is divided in the radial direction, so that the motor can be removed even if the motor has a lead wire or the like. Also, the lead wires can be attached to the motor before being assembled.

According to the fourth aspect of the present invention, since the contact piece is L-shaped, the entire L-shaped portion bends when a force is applied to the contact piece, so that the end face on the non-output side is bent. Deformation and the like can be prevented as compared with the case where only the contacted portion bends.

According to the fifth aspect of the present invention, the inner diameter of the contact piece of the motor holder is substantially the same as the outer circumference of the motor, and the inner diameter is gradually increased from there toward the case. The motor can be easily inserted from a large portion of the motor, and when the motor is inserted to a portion corresponding to the contact piece, the inner diameter and the outer periphery of the motor are almost the same, so that the motor can be held tightly.

According to the sixth aspect of the present invention, the gap between the rib, which is one step higher than the motor support, and the outer periphery of the motor is made smaller than the space between the driving magnet and the inner diameter of the motor support. For example, even when the pump is dropped and a radial force is applied to the motor, the output shaft does not deform because the drive magnet and the inner diameter of the motor support portion do not hit the rib and the motor first. .

According to the seventh aspect of the present invention, the motor holder is provided with an attaching portion to the electric water heater main body, and the case is floated from the main body, so that the heat transmitted from the main body to the seal portion of the case is reduced, and the seal is reduced. Performance can be stabilized. In addition, since there is no extra part such as a mounting portion of the main body in the case, it does not become a hindrance when assembling the case.

According to the eighth aspect of the present invention, the height of the convex portion for fitting the motor is made higher than the height of the pin for fitting the case. Since the holes are not fitted and become unstable, there is no possibility that a mistake is noticed and the holes are mistakenly assembled.

[Brief description of the drawings]

FIG. 1 is a sectional view of a centrifugal pump for an electric water heater showing a first embodiment of the present invention.

FIG. 2 is a partially cutaway side view of the electric water heater centrifugal pump attached to the electric water heater main body.

FIG. 3 is a perspective view of a main part of a centrifugal pump for an electric water heater showing a second embodiment of the present invention.

FIG. 4 is a side view of a centrifugal pump for an electric water heater showing a third embodiment of the present invention.

FIG. 5 is a perspective view of a main part of a centrifugal pump for an electric water heater showing a fourth embodiment of the present invention.

FIG. 6 is a sectional view of a centrifugal pump for an electric water heater showing a fifth embodiment of the present invention.

FIG. 7 is a sectional view of a main part of a centrifugal pump for an electric water heater showing a sixth embodiment of the present invention.

FIG. 8 is a plan view of a centrifugal pump for an electric water heater, showing a seventh embodiment of the present invention.

FIG. 9 is a side view of the centrifugal pump for an electric water heater.

FIG. 10 is a sectional view of a main part of a centrifugal pump for an electric water heater according to an eighth embodiment of the present invention.

FIG. 11 is a sectional view of a conventional centrifugal pump for an electric water heater.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Motor 11a Output shaft side end surface 11b Non-output shaft side end surface 12 Output shaft 13 Driving magnet 14 Case 15 Impeller 17 Motor support part 18 Motor holder 18a Motor holder bottom 20 Contact piece 25 Electrical connection terminal 26 Lead wire 27 Rib 28 gap 29 space 30 mounting part 31 convex part 32 concave part 33 pin 34 hole

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Hideho Mitsuhashi 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (8)

[Claims] A motor, a driving magnet fixed to an output shaft of the motor and having a diameter smaller than an outer diameter of the motor, an impeller magnetically coupled to the driving magnet and rotating; A motor holder that encloses the impeller and is provided with a motor supporting portion that abuts on an output shaft side end surface of the motor; and a motor holder that covers the motor and is fastened to the case. An electric water heater provided with a contact piece that is in contact with the opposite end face on the non-output side, and having the dimension from the motor support section end face to the contact piece substantially equal to the length of the body of the motor and supporting the motor in the length direction. Dexterous centrifugal pump. 2. The electric device according to claim 1, wherein a part of the bottom of the motor holder is cut out to form a contact piece in a beam shape, and the contact piece has elastic force in a longitudinal direction of the motor. Centrifugal pump for water heater. 3. An electric connection terminal attached to a motor, and a lead wire connected to the electric connection terminal, wherein the contact piece has a beam shape by cutting out a part of the bottom of the motor holder. The centrifugal pump for an electric water heater according to claim 1, wherein the contact piece is radially divided. 4. The centrifugal pump for an electric water heater according to claim 2, wherein the contact piece is radially divided and extended to the case side to form the contact piece into an L shape. 5. The electric motor according to claim 1, wherein the inner diameter of the contact piece of the motor holder is substantially the same as the outer periphery of the motor, and the inner diameter of the motor holder is gradually increased from the contact piece toward the case. Centrifugal pump for water heater. 6. A rib, one step higher than the motor support, is provided outside the motor support with a gap from the outer periphery of the motor, and the gap is made smaller than the space between the driving magnet and the inner diameter of the motor support. The centrifugal pump for an electric water heater according to claim 1. 7. The centrifugal pump for an electric water heater according to claim 1, wherein the motor holder is provided with a mounting portion to the electric water heater main body, and the case is mounted so as to float from the electric water heater main body. 8. A contact piece and a non-output side end face of a motor are provided with a convex portion and a concave portion which are fitted to each other, and a motor holder and a case are provided with a pin and a hole which are fitted to each other. The centrifugal pump for an electric water heater according to claim 1, wherein the height is higher than the height of the pin.