JP2009052531A - Metering high-pressure pump for foaming high-pressure urethane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a foaming agent contained in a component liquid from being gasified by a simple structure without using a dedicated pump when the component liquid constantly discharged by a pump function is circulated for cooling. <P>SOLUTION: This metering high-pressure pump having a magnet coupling structure comprises a connection part 8b connected to a drive shaft 4, a rotor inner first space part 8d disposed adjacent to the connection part 8b and communicating with a rotor outer space part 9, a rotor inner second space part formed in the connection part 8b, and a blade 8g disposed between the rotor inner first space part and a communication hole 8f serving as the rotor inner second space part. A negative pressure is generated by rotating an inner rotor 8 to rotate the blade 8g, and component liquid in the rotor inner first space part 8d is discharged to the outside of the inner rotor through the rotor inner second space part for circulating the component liquid introduced from a component liquid introduction space part through a pipe. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a metering high-pressure pump that is used for foaming high-pressure urethane and has a magnetic coupling structure for driving a cylinder block having a piston.

  A metering high-pressure pump is used to supply a component liquid for high-pressure urethane foam. Production of urethane foam is carried out by foaming a stock solution obtained by mixing a polyol component and a polyisocyanate component. Here, a quantitative high-pressure pump is used to quantitatively supply the polyol component (corresponding to the component liquid), but in order to prevent the component liquid from leaking to the outside, a pump drive using a magnet coupling structure is used. It is done.

  A piston pump is used as the high-pressure pump, and the component liquid sucked from the suction part is quantitatively discharged from the discharge part by driving a cylinder block having a plurality of pistons. The cylinder block is driven by a drive shaft that is rotationally driven by an electric motor. Here, a magnet coupling structure is employed to rotationally drive the drive shaft.

  The magnet coupling structure includes an inner rotor, an outer rotor, and a rotor casing that spatially blocks them. By driving the outer rotor with an electric motor, the inner rotor can be rotated by the magnetic force of the magnet, and the drive shaft can be driven to rotate. Since the space between the rotors can be completely spatially blocked, there is an advantage that the component liquid can be surely leaked.

  On the other hand, by adopting such a structure, it is necessary to cool the inner rotor and the like because they are heated. The rotor casing is also usually made of metal and generates heat due to the generation of eddy current. In order to perform such cooling, a part of the component liquid that is quantitatively discharged is introduced into the rotor casing.

  However, the configuration using the component liquid itself for cooling as described above has the following problems. With the heat generation of the inner rotor and the rotor casing, the component liquid (inner liquid) in the vicinity of the inner rotor is heated. The polyol component as the component liquid contains a foaming agent, and since the boiling point of this foaming agent is about 40 ° C., it is gasified and stays in the pump. If the gasified foaming agent is sucked, there is a possibility that the quantitative property is lowered or the pump is damaged.

  Further, when the heated component liquid is mixed into the component liquid discharged from the discharge portion, the temperature of the discharged component liquid rises, the reactivity of urethane foaming changes, and normal foam molding cannot be performed. Further, a magnetic force drop occurs with the heat generation and heat storage of the inner rotor, and normal drive transmission by the magnet coupling is not performed due to the step-out caused by this. For this reason, the desired pump rotation speed cannot be maintained, and there is a risk that the fixed discharge cannot be achieved.

  In order to cope with such a problem, it is only necessary to provide a path through which the component liquid circulates in order to cool the vicinity of the inner rotor. However, in order to circulate, it is necessary to provide a separate circulation pump. It becomes. Further, if a separate circulation pump is provided, countermeasures against leakage of component liquids at that location must be taken into account, and a new problem arises that the effect of providing a magnet coupling and sealing it is halved.

  The present invention has been made in view of the above circumstances, and the problem is realized with a simple configuration without using a dedicated pump when circulating a component liquid quantitatively discharged by the pump function for cooling. Another object of the present invention is to provide a metering high-pressure pump for foaming high-pressure urethane capable of preventing gasification of a foaming agent contained in a component liquid.

In order to solve the above problems, the metering high-pressure pump for high-pressure urethane foam according to the present invention is:
In the metering high-pressure pump used for high-pressure urethane foam and having a magnet coupling structure for driving a cylinder block having a piston,
A suction part for sucking component liquid for high-pressure urethane foam;
A discharge part for discharging a component liquid for high-pressure urethane foam;
The cylinder block for quantitatively discharging the component liquid sucked from the suction section from the discharge section;
A block space in which the cylinder block is accommodated;
A drive shaft for driving the cylinder block;
A component liquid introduction space for guiding the component liquid to the suction part;
An inner rotor integrally coupled with the drive shaft;
An outer rotor disposed on the outer periphery of the inner rotor and driven to rotate by an electric motor;
A rotor casing that is arranged between the inner rotor and the outer rotor and spatially blocks both of them,
A pipe for guiding the component liquid from the component liquid introduction space to the rotor outer space formed between the rotor casing and the outer periphery of the inner rotor,
The inner rotor is
A connecting portion connected to the drive shaft;
A first in-rotor space disposed adjacent to the connecting portion and communicating with the outer space of the rotor;
A second space in the rotor formed in the connecting portion;
A negative pressure generating member disposed between the first space part in the rotor and the second space part in the rotor,
The negative pressure is generated by rotating the negative pressure generating member by the rotation of the inner rotor, and the component liquid in the first space portion in the rotor is discharged out of the inner rotor through the second space portion in the rotor. A component liquid introduced from the component liquid introduction space through the pipe is circulated.

  The operation and effect of the high-pressure urethane foam quantitative high-pressure pump having such a configuration will be described. When the component liquid is discharged in a fixed amount, the cylinder block is driven, the component liquid is sucked from the suction part, and the fixed component liquid is discharged from the discharge part. The cylinder block is driven by a drive shaft, and a magnet coupling structure is employed to rotationally drive the drive shaft. By rotating the outer rotor with an electric motor, the inner rotor is driven to rotate by the action of magnetic force, and the drive shaft rotates. Since the rotor casing is disposed between the outer rotor and the inner rotor, it is possible to prevent the component liquid from leaking.

  The component liquid for cooling is introduced from the component liquid introduction space through a pipe, passes through the space between the outer circumference of the rotor casing and the inner rotor, and is guided to the first space in the rotor of the inner rotor. Further, in the inner rotor, a first in-rotor space portion and a second in-rotor space portion are disposed adjacent to each other, and a negative pressure generating member is disposed therebetween. When the inner rotor rotates, the component liquid in the first rotor inner space portion is discharged to the outside of the inner rotor through the second inner rotor space due to the action of the negative pressure generating member. The discharged component liquid passes through the bearing of the drive shaft and moves to the block space where the cylinder block is accommodated. Therefore, when the inner rotor rotates, a negative pressure is generated in the first space portion in the rotor, a force for sucking the component liquid from the component liquid introduction space portion is generated, and the component liquid can be continuously circulated. . Thereby, it can suppress that the temperature of a component liquid rises. Further, the component liquid can be sucked into the pipe without using a dedicated pump, which can contribute to cost reduction. As a result, when the component liquid that is quantitatively discharged by the pump function is circulated for cooling, it is realized with a simple configuration without using a dedicated pump and prevents the foaming agent contained in the component liquid from being gasified It is possible to provide a quantitative high-pressure pump for foaming high-pressure urethane.

  In this invention, it is preferable that the spiral groove for guiding a component liquid is formed in the outer periphery of an inner rotor.

  The space outside the rotor formed on the outer periphery of the inner rotor is preferably a large gap in consideration of the passage of the component liquid, but is preferably narrow in view of the generation of magnetic force. Therefore, by forming a spiral groove on the outer periphery of the inner rotor, it is possible to satisfy both requirements of the space through which the component liquid passes and the generation of magnetic force.

  In the present invention, the negative pressure generating member is preferably a blade that rotates about the rotation axis of the inner rotor.

  By providing and rotating such blades, a negative pressure can be generated in the first space portion in the rotor, and a continuous flow of the component liquid can be created.

  In this invention, it is preferable that the said rotor 2nd space part is comprised by many communicating holes arrange | positioned along the outer periphery of a drive shaft.

  The second space portion in the rotor is formed in the connecting portion, but by forming the above-described many communication holes, the component liquid is supplied while maintaining the function as the connecting portion for connecting the drive shaft. It is also possible to have a function of discharging to the outside of the inner rotor.

  A preferred embodiment of a high-pressure urethane foam metering high-pressure pump according to the present invention will be described with reference to the drawings. In order to produce urethane foam in high-pressure urethane foaming, it is necessary to mix a polyol component and a polyisocyanate component. The metering high-pressure pump according to the present invention is used, for example, for quantitatively supplying a polyol component. The polyol component is composed of a polyol and a foaming agent, and it is necessary to prevent the foaming agent having a boiling point of about 40 ° C. from being gasified by heating.

<Configuration>
FIG. 1 is a cross-sectional view showing a configuration of a metering high-pressure pump. The metering high-pressure pump is roughly composed of a pump main part A and a magnet coupling part B. The type of pump is a piston pump. As the structure of the pump main part A itself, a known structure can be used.

  A component liquid inlet 1a is provided in the first main body 1, and the component liquid is introduced into the pump. A component liquid outlet 2a is provided in the second main body 2, and a fixed amount of component liquid is discharged outside the pump. A component liquid introduction space 1 b is formed in the first main body 1. A block space 2 b for accommodating the cylinder block 3 is formed inside the second main body 2. The interiors of the component liquid introduction space 1b and the block space 2b are filled with the component liquid.

  The cylinder block 3 is provided with a large number of pistons, sucks the component liquid from the suction part 2c, and discharges a fixed amount of the component liquid from the discharge part 2d. The component liquid discharged from the discharge part 2d is discharged out of the pump from the component liquid outlet part 2a through the internal passage 2e. A drive shaft 4 for driving the cylinder block 3 is provided coaxially with the cylinder block 3. The drive shaft 4 has a configuration in which a large diameter portion 4a and a small diameter portion 4b are connected coaxially. The large diameter portion 4a is integrally coupled to the cylinder driving portion 4c, and the piston in the cylinder block 3 can be driven by rotating the cylinder driving portion 4c. The large diameter portion 4 a is supported by the three bearings 5 with respect to the second main body portion 2.

  Next, a magnet coupling structure for rotationally driving the drive shaft 4 will be described. First, an electric motor 6 as a drive source is provided, and an electric shaft 6a is provided for drive transmission. An outer rotor 7 is fixed to the electric shaft 6a by a method such as press fitting, and a magnet 7a (permanent magnet or electromagnet) is disposed on the inner surface thereof.

  An inner rotor 8 is fixed to the drive shaft 4 by a method such as press fitting. A magnet 8 a is disposed on the outer surface portion of the inner rotor 8. The magnets 7a and 8a of the inner rotor 7 and the outer rotor 8 are in a positional relationship just facing each other. The inner rotor 8 includes a connecting portion 8b, a magnet holding portion 8c, and a first in-rotor space portion 8d. The connecting portion 8b and the magnet holding portion 8c are integrally formed, and the magnet 8a is mounted on the outer surface portion of the magnet holding portion 8c.

  The connecting portion 8b is fixed to the small diameter portion 4b of the drive shaft 4 by a method such as press fitting. The outer diameter of the outer peripheral part of the magnet holding part 8c is set to be larger than the outer diameter of the outer peripheral part of the connecting part 8b, and a step part 8e is formed between them. The internal space of the magnet holding part 8c functions as the first space part 8d in the rotor, and becomes a space into which the component liquid for cooling is introduced. The inner diameter of the first rotor inner space portion 8 d is set to be larger than the diameter of the small diameter portion 4 b of the drive shaft 4.

  8 f of communicating holes which function as the 2nd space part in a rotor are arranged in the inside of connecting part 8b at equal intervals along the peripheral direction. FIG. 2 is a plan view of the connecting portion 8b as viewed from the left side of FIG. The small-diameter portion 4b of the drive shaft 4 is connected to the center of the connecting portion 8b, and six communication holes 8f are disposed around the small diameter portion 4b. The number of the communication holes 8f arranged, the arrangement pitch, the cross-sectional shape, and whether or not to make them equidistant can be determined as appropriate. Further, the inner diameter of the communication hole 8f may be different between the inlet side and the outlet side. By providing such a communication hole 8f, it is possible to have a function of discharging the component liquid to the outside of the inner rotor 8, and also to have a function (strength) for connecting the drive shaft 4.

  A blade 8g (corresponding to a negative pressure generating member) is disposed between the communication hole 8f (second rotor inner space) and the first rotor inner space 8d. FIG. 3 shows the shape of the blade 8g as viewed in the axial direction from the right side of FIG. As shown in FIG. 3, six blades 8g are arranged at equal intervals along the circumferential direction. The communication hole 8f is positioned between the blade 8g and the blade 8g. However, in the present invention, the number of blades 8g can be set as appropriate, and does not need to match the number of communication holes 8f. Further, the phase relationship in the circumferential direction between the communication hole 8f and the blade 8g may be other than the configuration shown in FIG.

  The communication hole 8f has a straight portion 8f1 as shown in FIG. 1, and is connected to a space 8f2 on the back side of the blade 8g. As shown in FIG. 1, the space 8f2 on the back side of the blade 8g is inclined with respect to the rotation axis of the inner rotor 8, and is connected to a round hole formed at the center of the blade 8g group. By providing such an inclined space 8f2, the component liquid can be guided from the round hole to the straight portion 8f1 of the communication hole 8 by the action of centrifugal force. Further, by rotating the blade 8g, it is possible to positively generate a negative pressure in the first in-rotor space portion 8d, and to create a component liquid flow.

  A rotor casing 9 is disposed between the surface of the magnet 8a of the inner rotor 8 and the surface of the magnet 7a of the outer rotor 7, and completely blocks the outer rotor 7 and the inner rotor 8 spatially. The inner rotor 8 and the outer rotor 7 need to be as close as possible to obtain the magnetic force as much as possible. A gap between the surface of the magnet 8a of the inner rotor 8 and the inner wall surface of the rotor casing 9 functions as a space outside the rotor for allowing the component liquid to pass therethrough.

  The connector 10 is a member for connecting the electric motor 6 and the pump main part A. The connector 10 is formed with a flange portion 10 a and functions as an attachment portion of the electric motor 6. The rotor casing 9 is also formed with a flange portion 9 b and is attached to the inner surface portion 10 b of the connector 10. An attachment portion 9c is provided at the end of the connector 10 opposite to the side on which the flange portion 10a is provided, and is coupled to the second main body portion 2. With the configuration of the rotor casing 9 and the connector 10, the component liquid can be sealed so as not to leak completely.

  On the side of the attachment portion 10c of the connector 10, an internal passage 10d for passing the component liquid is formed. A connecting portion 1c for connecting the pipe 11 is provided on the side portion of the component liquid introducing space portion 1b, and the other end of the pipe 11 is connected to the connecting portion 10e of the connector 10.

  A partition wall 12 is provided to shield the internal passage 10d formed in the connector 10 and the space on the outlet side of the through hole 8f. As a result, a circulation path for guiding the component liquid in the component liquid introduction space 1b toward the inner rotor 8 is formed.

<Operation>
Next, the operation of the metering high pressure pump shown in FIG. 1 will be described. When the electric motor 6 is driven, the outer rotor 7 is rotationally driven. The inner rotor 8 is rotationally driven by the action of the magnet 7a of the outer rotor 7 and the magnet 8a of the inner rotor 8, and the drive shaft 4 integrated therewith also rotates. Thereby, the cylinder block 3 is driven, the component liquid is sucked from the suction part 2c, and is quantitatively discharged from the discharge part 2d.

  On the other hand, when the inner rotor 8 is driven to rotate, the blades 8g also rotate in the same manner, and the component liquid in the rotor inner space 8d is sucked into the communication hole 8f by the action of centrifugal force, and is discharged to the outside of the inner rotor 8. Discharged. The component liquid discharged from the outlet side of the communication hole 8f is transmitted through the portion of the bearing 5 and moves in the direction of the block space portion 2b and the component liquid introduction space portion 1.

  Since the component liquid is sucked by the rotation of the blade 8g, a negative pressure is generated, and a force for sucking the component liquid from the component liquid introduction space 1b through the pipe 11 acts. The component liquid introduced into the pipe 11 passes through the internal passage 10 d in the connector 10 and the rotor outer space 9 a and is guided into the first rotor inner space 8 d of the inner rotor 8. Therefore, the component liquid can be continuously introduced (circulated) through the pipe 11 as long as the negative pressure continues to be generated.

  Heat is generated due to rotation of the inner rotor 8 and eddy current generated in the rotor casing 9, which causes the component liquid to be heated. However, by providing the blade 8g and the communication hole 8f, the component liquid is positively activated. Therefore, the heated component liquid does not stay in the same place and can be prevented from being heated more than necessary. Therefore, the problem that the component liquid is heated and gasified above the boiling point of the foaming agent contained in the component liquid can be eliminated, and stable quantitative discharge can be performed. In addition, it is possible to eliminate the failure of the pump due to the generation of bubbles. Further, the component liquid can be sucked in the direction of the inner rotor 8 without using a dedicated pump, and the cost can be reduced.

<Another embodiment>
FIG. 2 is a diagram illustrating a configuration of another embodiment of the inner rotor 8. In this embodiment, a spiral groove 8g is formed on the surface of the magnet 8a. The gap size of the outer rotor space 9a is preferably as small as possible, but if it is too narrow, the component liquid will not flow easily. Therefore, the flowability of the component liquid can be ensured by forming the spiral groove 8g as shown in FIG.

  About the component liquid used as object in this invention, it is not limited to specific things, such as the kind of foaming agent. The present invention can be applied not only to the quantitative supply of the polyol component but also to the quantitative supply of the polyisocyanate component.

Sectional view showing the configuration of the metering high-pressure pump Plan view showing the shape of the communication hole Plan view showing blade shape The figure which shows the structure of the inner rotor concerning another embodiment.

Explanation of symbols

1b Component liquid introduction space portion 2b Block space portion 2c Suction portion 2d Discharge portion 3 Cylinder block 4 Drive shaft 5 Bearing 6 Electric motor 7 Outer rotor 7a Magnet 8 Inner rotor 8a Magnet 8b Connection portion first space portion 8f Communication hole 8f1 Linear portion 8f2 Space 8g Blade 9 Rotor casing 9a Space outside the rotor 11 Pipe

Claims (4)

In the metering high-pressure pump used for high-pressure urethane foam and having a magnet coupling structure for driving a cylinder block having a piston,
A suction part for sucking component liquid for high-pressure urethane foam;
A discharge part for discharging a component liquid for high-pressure urethane foam;
The cylinder block for quantitatively discharging the component liquid sucked from the suction section from the discharge section;
A block space in which the cylinder block is accommodated;
A drive shaft for driving the cylinder block;
A component liquid introduction space for guiding the component liquid to the suction part;
An inner rotor integrally coupled with the drive shaft;
An outer rotor disposed on the outer periphery of the inner rotor and driven to rotate by an electric motor;
A rotor casing that is arranged between the inner rotor and the outer rotor and spatially blocks both of them,
A pipe for guiding the component liquid from the component liquid introduction space to the rotor outer space formed between the rotor casing and the outer periphery of the inner rotor,
The inner rotor is
A connecting portion connected to the drive shaft;
A first in-rotor space disposed adjacent to the connecting portion and communicating with the outer space of the rotor;
A second space in the rotor formed in the connecting portion;
A negative pressure generating member disposed between the first space part in the rotor and the second space part in the rotor,
The negative pressure is generated by rotating the negative pressure generating member by the rotation of the inner rotor, and the component liquid in the first space portion in the rotor is discharged out of the inner rotor through the second space portion in the rotor. A quantitative high-pressure pump for foaming high-pressure urethane, characterized in that the component liquid introduced from the component liquid introduction space through the pipe is circulated.   2. The metering high-pressure pump for foaming high-pressure urethane according to claim 1, wherein a spiral groove for guiding the component liquid is formed on the outer periphery of the inner rotor.   The metering high-pressure pump for foaming high-pressure urethane according to claim 1 or 2, wherein the negative pressure generating member is a blade rotating around a rotation axis of an inner rotor.   4. The high-pressure urethane foaming device according to claim 1, wherein the second space portion in the rotor is constituted by a plurality of communication holes arranged along an outer periphery of the drive shaft. Metering high pressure pump.

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