JP2015048751A - Blower - Google Patents

Abstract

An object of the present invention is to open a valve during motor driving to efficiently cool the inside of the motor case and close the motor case when motor driving is stopped, thereby closing a cooling vent and preventing moisture (moisture) and foreign matter from entering. Provide a blower with improved reliability.
A check valve 14 closes a second vent hole 6e while driving of a motor M is stopped, and a pressure of compressed air introduced into a motor case 6 from the first vent hole 6d while the motor is driven. And the compressed air is exhausted from the second vent 6e.
[Selection] Figure 3

Description

  The present invention relates to a blower provided with an air cooling mechanism for a motor.

  Various spindle devices for cooling a motor for driving a rotating body have been proposed. For example, in order to rotate a polygon mirror used in a digital copying machine, a laser beam printer, or the like with a motor at a high speed, a large current is applied by increasing the wire diameter of the motor coil. However, as the amount of current flowing through the motor coil increases, the amount of heat generation also increases and the temperature rise of the motor becomes significant. Alternatively, heat is also generated from a bearing portion that rotatably supports the rotor.

  For this reason, for example, an intake hole is provided in a mirror case that accommodates a polygon mirror, an exhaust hole is provided in a motor case that accommodates a motor, and a communication hole is provided in an isolation member that separates the mirror case and the motor case. A spindle apparatus having a communication hole at a position has been proposed. When the motor coil is energized, the polygon mirror rotates through the rotor, and the air sucked from the suction hole due to the negative pressure generated at the outer periphery of the polygon mirror flows from the rotation center of the polygon mirror to the outer periphery, and the communication hole of the partition member Into the motor case. Then, the air flows through the motor core through the communication hole of the motor core to the exhaust hole so that hot air is exhausted to the outside of the motor case, thereby cooling the motor stator (see Patent Document 1).

JP-A-8-275457

In the spindle device described above, while the motor is driven, an air flow is generated from the intake hole of the mirror case toward the exhaust hole of the motor case as the rotating body (polygon mirror) rotates. When the spindle device is placed in a hot and humid environment, for example, moisture (moisture) and foreign matter can easily enter the case from the exhaust hole that is always open to the motor case. There was a risk of damaging parts.
Further, if a through-hole is formed in the motor core for cooling the stator, man-hours are required and the manufacturing cost is increased, and the magnetic flux passage is reduced and the motor performance may be lowered.

  The present invention has been made to solve these problems. The object of the present invention is to cool the motor case by opening the valve while the motor is driven and cooling the motor case efficiently and closing the motor when the motor is stopped. It is an object of the present invention to provide a blower with improved reliability by closing a ventilation hole for preventing moisture (moisture) and foreign matter from entering.

In order to achieve the above object, the present invention comprises the following arrangement.
A blower case that accommodates the impeller and a motor case that accommodates the stator and the rotor are integrally assembled, and an impeller is assembled in the blower case to a shaft that passes through these, and the rotor is assembled in the motor case. A blower that sucks outside air from the axial direction into the blower case by rotation of the impeller and blows air from the circumferential direction, and introduces a part of the compressed air from the blower case from one axial end surface of the motor case. And a second vent hole that exhausts compressed air that has passed through the motor case from the other axial end surface to the outside of the case, and a check valve that opens and closes the second vent hole, and stops driving the motor. The check valve closes to close the second vent hole, and the pressure of the compressed air introduced into the motor case from the first vent hole during driving of the motor. In and opened, characterized in that the exhaust from the second vent hole of the compressed air.

Thus, when the impeller rotates during driving of the motor, a part of the compressed air is introduced into the motor case from the blower case through the first ventilation hole from the axial end surface of the motor case, and the compressed air that has passed through the motor case is introduced. Is opened to the outside of the motor case through the second vent by opening a check valve for closing the second vent provided in the other axial end surface. A part can be used for cooling.
In addition, when the motor is stopped, the check valve closes and the second vent hole is closed, so that moisture (moisture) and foreign matter do not enter the case from the exhaust hole of the motor case. There is no risk of damage to electronic components mounted on the board.

  The first vent hole is formed at a plurality of locations around the shaft, and the second vent hole is formed by shifting a predetermined angle around the first vent hole and the shaft at a central angle. Then, the compressed air flowing into the motor case from the first vent hole first cools the motor core that is likely to generate heat, turbulently flows in the motor case, and then exhausted from the second vent hole. Can be cooled.

  In addition, the check valve uses a forced check valve or a free check valve according to the installation position of the motor, so that an optimum check valve structure can be adopted according to the installation position of the motor in the blower. .

  If the above-mentioned blower is used, the valve opens while the motor is driven to efficiently cool the inside of the motor case, and closes when the motor is stopped, thereby closing the cooling vent and allowing moisture (moisture) or foreign matter to enter. Thus, it is possible to provide a blower that is prevented from being improved and has improved reliability.

It is the top view which looked at the air blower from the motor case side. It is the top view which looked at the air blower from the blower case side in the state which omitted the impeller. FIG. 3 is an arrow XX cross-sectional view of FIG. 1 and an enlarged cross-sectional view of a check valve that opens and closes a second vent hole.

Hereinafter, an embodiment of a blower according to the present invention will be described with reference to the accompanying drawings.
A schematic configuration of the blower will be described with reference to FIGS. 1 to 3.
As shown in FIG. 3, the blower 1 is integrally assembled with a blower case 3 in which the impeller 2 is accommodated and a motor case 6 in which the stator 4 and the rotor 5 (motor M) are accommodated.
An impeller 2 is assembled in the blower case 3 to a shaft 7 that passes through the blower case 3 and the motor case 6, and a rotor 5 is assembled in the motor case 6. The stator 4 is assembled to the inner wall of the motor case. When the motor M is started, the blower 1 sucks air from the axial direction into the blower case 3 by rotation of the impeller 2 and blows compressed air from the circumferential direction.

  In FIG. 3, the blower case 3 is formed by combining a first blower case 3a and a second blower case 3b. A suction port 3c for sucking fluid (air) is formed at the center of the first blower case 3a. Concave grooves are formed in the outer peripheral edge portions of the first blower case 3a and the second blower case 3b, and the compression chambers 3e (flow paths) are formed by overlapping them facing each other. Further, a discharge port 3d extending in the tangential direction is formed on the outer peripheral surface of the blower case 3 (see FIG. 2). One end of a shaft 7 is inserted into the blower case 3, and the impeller 2 is integrally assembled with the shaft 7. The impeller 2 is integrally assembled to one end of the shaft 7 by molding, bonding, press fitting, or the like. Blades 2 a are formed radially on the impeller 2.

  In FIG. 2, the motor case 6 is integrally assembled on the side opposite to the suction port 3c of the blower case 3 surrounded by the compression chamber 3e, that is, on the second blower case 3b side. In FIG. 3, the motor case 6 is formed by combining a first motor case 6a and a second motor case 6b. A stepped portion 6c is formed on the end surface A serving as a mounting surface of the first motor case 6a, and is fitted into the central hole 3f of the second blower case 3b and integrally assembled. On the end surface A of the first motor case 6a facing the blower case 3, first vent holes 6d for introducing a part of the compressed air from the blower case 3 into the motor case 6 are equidistant around the shaft 7 (for example, Perforated at a plurality of locations (for example, 3 locations) at intervals of 120 ° in the central angle. That is, the first air hole 6d is disposed on the side of the impeller 2 opposite to the surface on which the blade 2a is formed.

  Next, the configuration inside the motor case 6 will be described. In FIG. 3, the shaft 7 is rotatably supported by bearings 6h provided in the first motor case 6a and the second motor case 6b, respectively. As the bearing portion 6h, a sliding bearing (for example, a metal oil-impregnated bearing, a fluid dynamic bearing, etc.) is used in addition to a rolling bearing. A rotor (rotor magnet) 5 is concentrically assembled to the shaft 7. A motor core 8 that forms the stator 4 is fixed to the inner wall surface of the first motor case 6a, and pole teeth projecting radially inward from the motor core 8 facing the rotor 5 ( A motor coil 10 is wound around the tooth portion via an insulator 9.

  Further, the motor substrate 11 is held in the second motor case 6 b by a substrate holding portion 9 a that protrudes from the insulator 9. An electronic component (for example, Hall IC) 12 or the like is mounted on the motor substrate 11. An escape hole 11 a through which the shaft 7 is inserted is formed at the center of the motor substrate 11. The other end of the shaft 7, that is, the shaft end opposite to the impeller 2, is supported by a thrust receiver 15 provided in the second motor case 6 b. The shaft end of the shaft 7 is formed in an R surface shape and rotates while being in contact with the thrust receiver 15. As the thrust receiver 15, a resin material (for example, PEEK (polyether ether ketone) material) having excellent sliding characteristics with the shaft 7 is used.

In FIG. 1, a second air hole for exhausting compressed air that has passed through the motor case 6 to the outside of the end surface B of the second motor case 6 b (an end surface opposite to the mounting surface A of the first motor case 6 a in the axial direction). 6e is perforated at a plurality of locations (for example, 3 locations) around the shaft 7 at regular intervals (for example, 120 ° intervals at the central angle). The second ventilation hole 6e is not limited to the axial end surface B of the second motor case 6b, and may be provided on the side surface in the vicinity thereof.
Further, a lead hole 6f through which a lead wire 13 for feeding power to the motor coil 10 is drawn is formed in the end surface B of the second motor case 6b.

  As shown in the enlarged view of FIG. 3, a check valve 14 for opening and closing the second ventilation hole 6e is provided at the opening of the second ventilation hole 6e. The check valve 14 includes a valve main body 14a, a valve section 14b that is seated on a seating section 16 formed at the opening of the second vent 6e and blocks the flow path, and the valve main body 14a is caused to flow by fluid pressure. And a retaining portion 14c for preventing. In the valve body 14a, a valve portion 14b that contacts and separates from a seating portion 16 formed in a tapered shape at the opening of the second ventilation hole 6e and other portions are constituted by a plurality of parts. When the fluid pressure (pneumatic pressure) acts, the retaining portion 14c is locked to the retaining guide portion 6g provided in the second motor case 6b, thereby preventing the check valve 14 from coming out of the motor case 6. It is preventing.

  The valve portion 14b and the valve main body 14a including the retaining portion 14c are made of different materials or a combination of rubber materials having different hardnesses. Specifically, the valve portion 14b seated on the seat portion 16 is preferably made of a flexible material that is easily deformable or a soft rubber material. The valve body 14a is made of a material that is difficult to deform or a hard rubber material. In addition to changing the hardness of the rubber material, the valve portion 14b may be formed with a thin rubber material. Further, the planar shape of the check valve 14 is formed in a circular shape having one axis parallel to the fluid flow path. The check valve 14 may be either a forced check valve that closes by receiving external force or a free check valve that closes by its own weight, and an optimal check valve structure according to the motor installation position in the blower 1. Can be adopted. Further, the check valve may have another configuration such as an elastically deformable plate-like valve.

  Further, the positional relationship between the first ventilation hole 6d (see FIG. 2) and the second ventilation hole 6e (see FIG. 1) may be a position overlapping in the axial direction, but the second ventilation hole 6e is connected to the first ventilation hole 6d. It is preferable that the center angle of the shaft 7 is shifted by a predetermined angle (for example, 60 °) (see FIGS. 1 and 2). As a result, a part of the compressed air flowing into the motor case 6 from the first air hole 6d first turbulently flows in the motor case 6 as indicated by the broken line arrow in FIG. Since the air is exhausted through the two air holes 6e, the inside of the motor case 6 can be efficiently cooled.

  Here, the operation of the check valve 14 will be described. When the motor is stopped, the check valve 14 is closed to close the second ventilation hole 6e. That is, the valve portion 14b contacts the seating portion 16 and deforms to close the second vent 6e. Thereby, moisture (moisture) and foreign matter do not enter the case from the exhaust hole of the motor case 6, and there is no possibility of damaging the electronic component 12 mounted on the motor substrate 11.

  When the motor is started and the impeller 2 rotates, a part of the compressed air is introduced into the motor case 6 from the blower case 3 through the first vent hole 6d, and the compressed air that has passed through the motor case 6 is opposite in the axial direction. By opening the check valve 14 provided on the surface side by air pressure, the air is exhausted out of the motor case 6 through the second vent 6e. That is, the valve portion 14b is separated from the seating portion 16 to open the second ventilation hole 6e. Thereby, the inside of the motor case 6 can be cooled using a part of compressed air for ventilation.

Although the said Example demonstrated using the inner rotor type motor, if it is a structure which can ensure the air permeability of a rotor yoke, it can apply also to an outer rotor type motor.
Further, the number (three locations) of the first ventilation holes 6d and the second ventilation holes 6e and the arrangement relationship (arranged by shifting their phases by 60 °) are not limited to the above-described embodiments. The number can be further increased or decreased, and the arrangement relationship between the vents can be changed. In addition, the shape of the second vent 6e for opening and closing the check valve 14 is not limited to a circle and may be another shape.

  DESCRIPTION OF SYMBOLS 1 Blower 2 Impeller 3 Blower case 3a 1st blower case 3b 2nd blower case 3c Suction port 3d Discharge port 3e Compression chamber 3f Center hole 4 Stator 5 Rotor 6 Motor case 6a 1st motor case 6b 2nd motor case 6c Stage 6d First vent hole 6e Second vent hole 6f Drawer hole 6g Retaining prevention guide portion 6h Bearing portion 7 Shaft 8 Motor core 9 Insulator 10 Motor coil 11 Motor substrate 12 Electronic component 13 Lead wire 14 Check valve 14a Valve body 14b Valve Part 14c retaining part 15 thrust receiver 16 seating part

Claims (3)

A blower case that accommodates the impeller and a motor case that accommodates the stator and the rotor are integrally assembled, and an impeller is assembled in the blower case to a shaft that passes through these, and the rotor is assembled in the motor case. A blower that sucks outside air from the axial direction into the blower case by rotation of the impeller and blows air from the circumferential direction,
A first ventilation hole for introducing a part of compressed air from the blower case from one end surface in the axial direction of the motor case;
A second vent hole for exhausting the compressed air that has passed through the motor case from the other axial end surface to the outside of the case;
A check valve for opening and closing the second vent hole,
When the motor is stopped, the check valve is closed to close the second vent hole, and while the motor is driven, the check valve is opened by the pressure of the compressed air introduced into the motor case from the first vent hole. The blower is characterized in that the compressed air is exhausted from the second vent hole.   The first vent hole is formed at a plurality of locations around the shaft, and the second vent hole is formed by shifting a predetermined angle at a central angle around the first vent hole and the shaft. The blower according to 1.   The blower according to claim 1 or 2, wherein a forced check valve or a free check valve is used as the check valve.

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