JP2006233836A - Pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pump in which a heating part certainly radiates heat even when arranged anywhere, and stable performance is exerted. <P>SOLUTION: An impeller 4 is stored by a separation plate 8 and a casing 1, a stator 7a is arranged in an annular recess of the separation plate 8, and a rotor 5 driven by the stator 7a is formed in a pump chamber of the annular recess. A substrate mounting a stator 7a and a drive circuit 9, and a pipe 10 in which circulation water divided at a passage in the pump chamber flows are molded with a low thermal resistance resin. Since the received heat in the resin mold is promoted to radiate from the inside, the heat is certainly radiated even if arranged anywhere so that the cooling performance of a motor can be improved. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a pump in which a rotor sealed by a motor frame and a casing and a stator for driving the rotor are provided outside the motor frame.

  A conventional pump will be described with reference to the drawings.

  FIG. 2 is a structural diagram of a conventional pump. As shown in FIG. 2, an impeller 104 and a rotor 105 that pressurize fluid are fixed by a casing 101 and a motor frame 108 inside a casing 101 having a suction port 102 and a discharge port 103 and sealed by a motor frame 108. The shaft 106 is provided so as to be rotatable about the pillar 106.

  Further, the stator 107 and the drive circuit 109 for driving the motor constitute a motor frame 108 by a molding material 111 that is integrally molded using a low thermal resistance resin.

  The motor frame 108 constitutes a part of the flow path in the pump chamber. Further, the motor frame 108 is covered with an outer case 110 that is slightly larger than the motor frame 108, so that the motor frame 108 is surrounded by the outer case 110 and the outer case 110. The flow path 112 is provided.

  With the structure described above, the molding material 111 is in direct contact with the flow path in the pump chamber and the flow path 112 on the outer peripheral side, so that heat generation components such as the stator 107 and the drive circuit 109 can be radiated due to a temperature difference from the fluid.

Considering the heat radiation of the drive circuit 109, the heat conductivity λ of the molding material 111, the loss power W of the driving circuit 109, the heat radiation area S from the driving circuit 109, and the thickness of the molding material 111, the distance from the driving circuit 109 to the flow path 112. When the distance L2 and the water temperature Tw of the flow path 112 are given, the case temperature Tc2 of the drive circuit 109 is
Tc2 = (W × L2) / (λ × S) + Tw (Formula 1)
It is expressed simply.
JP 11-166500 A

  However, in the conventional configuration, since cooling by heat exchange is performed in the flow path of the outer peripheral portion of the resin-molded motor frame, the motor drive circuit and the stator, which are heat generating components, must be arranged near the flow path. There was a problem that a sufficient heat dissipation effect was not obtained and cooling was not possible efficiently.

  In addition, in order to arrange the heat-generating component near the flow path, the thickness of the resin molded between the flow path and the heat-generating component must be reduced, which may cause pinholes during molding or change over time. When the liquid enters the resin due to deterioration of the resin and reaches the heat generating component, the insulation may be deteriorated.

  The present invention solves such a conventional problem, and provides a pump that can reliably perform heat exchange to cool a heat generating component and maintain stable performance regardless of where the heat generating component is arranged. For the purpose.

  In order to achieve the above object, the present invention accommodates a casing containing an impeller for sucking and discharging liquid, a rotor connected to the impeller for rotating the impeller, a stator for driving the rotor, and a drive circuit for controlling the stator. A separation plate that isolates the casing and the motor unit and protects the motor unit, and a part of the liquid discharged from the impeller is introduced into the motor unit and generated in the stator and the drive circuit. A pipe for cooling the heat, the pipe is arranged at a predetermined distance close to the stator and the drive circuit, and the heat generated in the stator and the drive circuit is conducted to the pipe and injected into the motor unit, the stator and the drive circuit, It is characterized by providing a resin for molding the pipe.

  With this configuration, the heat generated in the heat generating component in the motor unit can be exchanged with the liquid flowing in the pipe disposed at a predetermined distance close to the heat generating component, thereby effectively cooling the motor unit.

  In the present invention, heat generated by the heat generating component in the motor unit is exchanged by a liquid flowing in a pipe arranged at a predetermined distance close to the heat generating component, and the motor unit is efficiently cooled to any of the heat generating components. Even if it arrange | positions, it is effective in the ability to provide the pump which performs heat exchange reliably, cools a heat-emitting component, and can maintain the stable performance.

  An embodiment of the present invention includes a casing containing an impeller that sucks and discharges liquid, a rotor that is connected to the impeller and rotates the impeller, a stator that drives the rotor, and a motor unit that houses a drive circuit that controls the stator. And separating the casing and the motor unit to protect the motor unit, and cooling the heat generated in the stator and the drive circuit by introducing a part of the liquid discharged from the impeller into the motor unit The pipe is disposed at a predetermined distance close to the stator and the drive circuit, and the stator, the drive circuit, and the pipe are molded by being injected into the motor unit to conduct heat generated in the stator and the drive circuit to the pipe. The resin to be used is provided.

  As a result, heat generated by the heat generating components in the motor unit is exchanged by the liquid flowing in the pipes arranged at a predetermined distance close to the heat generating components, and the heat generating components are placed anywhere by efficiently cooling the motor unit. Even in such a case, it is possible to provide a pump that can reliably perform heat exchange to cool the heat-generating component and maintain stable performance.

  The pipe may be made of a metal having a thermal resistance lower than that of the resin.

  Thereby, the thermal resistance between the liquid flowing in the pipe and the molded resin can be lowered, and the motor can be cooled more efficiently.

  In addition, the pipe may have a circular cross section.

  Thereby, when resin is inject | poured and a heat-emitting component and piping are molded, the deformation | transformation of piping by the molding pressure at the time of molding can be prevented.

  Further, the pipe may be provided at a predetermined place near the outer peripheral portion of the impeller with an inlet of the pipe, and disposed at a predetermined place near the back surface of the rotor.

  With this configuration, the liquid can be circulated in the pipe due to the pressure difference generated inside the casing.

  Then, if the pipe is connected so that the inlet and outlet of the pipe pass through predetermined positions of the separation plate, the resin is injected and molded in a state where the stator, the drive circuit and the pipe are fixedly arranged in the motor frame. be able to.

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

Example 1
FIG. 1 is a structural diagram of a pump showing Embodiment 1 of the present invention. In FIG. 1, an impeller 4 that pressurizes a fluid and a rotor 5 that is integrally molded with the impeller 4 are separated from the casing 1 inside a casing 1 having a suction port 2 and a discharge port 3 and sealed inside by a separation plate 8. It is provided so as to be rotatable about a shaft 6 fixed and supported by a plate 8.

  The stator 7a accommodated in the motor unit 7 is fixed to the annular recess of the separation plate 8, and the drive circuit 9 for driving the stator 7a is fixed to the stator 7a. The pipe 10 is a metal pipe made of a low heat resistance material such as aluminum or copper, and the cross section of the pipe 10 is formed in a circular shape such as a perfect circle or an ellipse.

  One end of the pipe 10 is connected to the outer peripheral part of the impeller 4 or a separation plate 8 near the discharge port 3 via an O-ring 11, and the middle of the pipe 10 is very close to the stator 7 a and the drive circuit 9 which are heat generating parts. The other end is connected to the separation plate 8 on the bottom surface of the rotor 5 via an O-ring 12.

  Reference numeral 13 denotes a molding material which is molded by using unsaturated polyester or the like which is a low thermal resistance resin integrally with the separation plate 8, the stator 7a, the drive circuit 9, and the pipe 10.

  Since a high pressure of about 5 MPa is applied at the time of molding, the pipe 10 having a hollow inside is deformed to have a cylindrical shape that is not easily deformed so as not to block the flow path.

  Further, in the vicinity of the shaft 6, which is the center of the impeller 4, a reflux hole 14 for generating a flow on the back side of the impeller 4 and the rotor 5 is provided.

  In the above configuration, when the stator 7a is energized from the drive circuit 9, a rotating magnetic field is generated in the stator 7a and the rotor 5 rotates. Since the impeller 4 is fixed to the rotor 5, when the rotor 5 rotates, the impeller 4 also rotates to pressurize the fluid.

  By applying pressure, the outer peripheral side of the impeller 4 becomes high pressure, and the vicinity of the suction port 2 in the center becomes negative with respect to the outer peripheral side. The actual fluid movement flows from the suction port 2, is pressurized by the impeller 4, and is discharged from the discharge port 3.

  When the fluid is pressurized, a pressure difference is generated between the front and rear of the impeller 4 and a thrust load is applied to the rotor 5, and a fluid flow is generated from the rear surface of the impeller 4 and the rotor 5 to the suction port 2 side through the reflux hole 14.

  Further, since the pipe 10 is connected to the outer peripheral side of the impeller 4 and the separation plate 8 on the bottom surface of the rotor 5, the separation plate on the bottom surface of the rotor 5 from the one connected to the outer peripheral side of the impeller 4 due to the pressure difference as described above. A flow of fluid is generated toward the one connected to 8.

  The pipe 10 arranged in the immediate vicinity receives the heat of the molding material 13 that has received the heat of the stator 7a and the drive circuit 9 that have generated heat due to this flow and dissipates it to the fluid.

Considering the heat radiation of the drive circuit 9, the distance L1 from the drive circuit 9 to the pipe 10 is determined by the thermal conductivity λ of the molding material 13, the loss power W of the driving circuit 9, the heat radiation area S from the driving circuit 9, and the thickness of the molding material. When the heat dissipation area s and thickness d of the pipe 10 having the thermal conductivity λm and the water temperature Tw of the flow path in the pipe 10 are given, the case temperature Tc1 of the drive circuit 9 is
Tc1 = (W × L1) / (λ × S) + (W × d) / (λm × s) + Tw (Expression 2)
It is expressed simply.

Here, the pipe 10 is λm = about 200 [W / mK] in the case of aluminum, and about 385 [W / mK] in the case of copper, and the molding material 13 is unsaturated polyester and λ = about 0.9 [W / mK]. Therefore, since λm >> λ, (Equation 2) becomes
Tc1 = (W × L1) / (λ × S) + Tw (Expression 3)
This is the same as (Equation 1). In this case, since it is easy to make the thickness L1 <L2 of the molding material 13, the case temperature Tc1 <Tc2 of the drive circuit 109 can be lowered.

  Thus, since the pump of the first embodiment promotes heat radiation of the resin mold that has received heat from the inside, heat can be reliably radiated regardless of where the heat generating components are arranged, and the cooling performance of the motor can be improved.

The pump of the present invention can be expected to be used as a pump that circulates and supplies hot water such as a hot water heater in an environment used under high temperatures.

Structural diagram of a pump showing Example 1 of the present invention Conventional pump structure

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Casing 2 Suction port 3 Discharge port 4 Impeller 5 Rotor 6 Shaft 7 Motor part 7a Stator 8 Separation plate 9 Drive circuit 10 Piping 11, 12 O-ring 13 Mold material 14 Reflux hole 101 Casing 102 Suction port 103 Discharge port 104 Impeller 105 Rotor 106 Shaft 107 Stator 108 Motor frame 109 Drive circuit 110 Outer case 111 Mold material 112 Flow path L1 Mold material thickness L2 Mold material thickness

Claims (5)

A casing having a built-in impeller for sucking and discharging liquid; a rotor connected to the impeller for rotating the impeller; a stator for driving the rotor; and a motor unit housing a drive circuit for controlling the stator; and the casing; A separation plate that isolates the motor unit and protects the motor unit; and a pipe that introduces a part of the liquid discharged from the impeller to the motor unit and cools the heat generated in the stator and the drive circuit. In addition, a pipe is arranged at a predetermined distance close to the drive circuit, and a resin is provided to mold the stator, the drive circuit, and the pipe to be injected into the motor unit in order to conduct heat generated in the stator and the drive circuit to the pipe. And pump. The pump according to claim 1, wherein the pipe is made of a metal whose thermal resistance is lower than that of a resin. The pump according to claim 1, wherein the pipe has a circular cross section. 4. The pipe according to claim 1, wherein an inlet of the pipe is provided at a predetermined place near the outer peripheral portion of the impeller, and an outlet of the pipe is arranged at a predetermined place near the back surface of the rotor. The pump described in. The pump according to claim 4, wherein an inlet and an outlet of the pipe are connected and fixed through a predetermined place of the separation plate.

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