JPH044735A - Fan - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a blower used, for example, for sucking air in a vacuum cleaner.

(Prior Art) There are various home appliances that use blowers. For example, a vacuum cleaner uses a blower to suck in air, and a combustion type heater using oil or gas uses a blower to exhaust air.

This blower is a combination of an electric motor, a blower fan provided at one end of the electric motor and rotated by the electric motor, and a fan cover surrounding the blower fan. A centrifugal type fan is used for the blower.

(Problems to be Solved by the Invention) However, this blower has the following problems.

The electric motor used in the blower includes a stator provided in the motor case and a rotor provided on the rotor shaft.
The rotor shaft is rotatably supported by a bearing provided in the motor case.

However, when the blower is operated, the temperature rises in the rotor shaft support bearing installed at the end of the motor case opposite the blower fan. The temperature of the rotor shaft bearing increases significantly,
Due to the influence of this temperature rise, there is a problem that the life of the bearing is short and economical is poor.

The present invention has been made based on the above-mentioned circumstances, and an object of the present invention is to provide a blower that suppresses the temperature rise of a bearing for supporting a rotor shaft of an electric motor and improves the life of the bearing.

(Means and Effects for Solving the Problems) The inventor of the present invention has repeatedly studied the temperature rise of a bearing provided in an electric motor in a blower.

In this process, the temperature of the electric motor's bearings rises because, in addition to the heat generated by the friction between the rotor shaft and the bearings, a major factor is the effect of heat generated around the stator of the electric motor. Ta. The heat generated by the stator heats up the bearing, causing its temperature to rise.

The reason why the temperature rise of the bearing installed at the end facing the blower fan in the motor case is smaller than the temperature rise of the bearing installed at the end opposite the blower fan is as follows. It turned out to be. At the end of the electric motor case facing the blower fan, air outside the blower is sucked by the blower fan. Therefore, the bearing provided at the end of the motor case facing the blower fan is cooled by the air sucked in by the blower fan, and temperature rise is suppressed.

Therefore, the inventor focused on cooling the bearing by using the air sucked by the blower fan, as a means of suppressing the temperature rise of the bearing provided at the end of the motor case opposite to the blower fan. did.

That is, this means cools the air flowing through the suction passage that guides air from the outside of the fan cover to the inside of the fan cover by bringing it into contact with a bearing provided at the end opposite to the blower fan. .

Conventionally, no consideration was given to using the air sucked in by the blower fan to cool the bearing installed at the end of the motor case opposite to the blower fan; Air is passed through the inside of the motor case from the end facing the blower fan to the end opposite the blower fan, cools the stator installed inside the case, and then discharged to the outside to blow the air. is being carried out.

However, with this method, the air force flowing inside the motor case (after being heated by the stator and rising in temperature, passes through the bearing installed at the end opposite to the blower fan, so the effect of cooling this bearing is not effective). It's gone.

The present invention was made based on this finding.

The blower of the present invention includes a stator and a rotor provided inside a motor case, a rotor shaft supported by a bearing provided in the motor case and to which the rotor is attached, and a motor of the motor. A blower comprising a blower fan provided at one end of the case and rotated by rotation of the rotor shaft, and a fan cover surrounding the blower fan, the blower having a suction port at one end, and the motor case. A suction air path is formed on the outside of the motor case, the bearing provided at the end opposite to the blower fan being included in the air path, and the other end communicating with the suction portion of the fan cover. It is characterized by this.

(Example) Examples of the present invention will be described below.

An embodiment of the present invention will be described with reference to FIGS. 1 to 4.

FIG. 1 shows the entire blower, in which 1 is an electric motor, 2 is a blower fan, 3 is a fan cover, 4 is a suction air path, and 5 is an output air path.

The electric motor 1 will be explained. The motor case 6 is constructed by integrally fixing a front case 7 having a cylindrical shape with a bottom and a rear case 8 having a cylindrical shape with a bottom by abutting their respective openings. A ball bearing 9 for supporting the rotor shaft is mounted in a bearing mounting hole 7a formed in the center of the end face of the front case 7, and a ball bearing 9 for supporting the rotor shaft is mounted in a bearing mounting hole 8a formed in the center of the end face of the rear case 8. A ball bearing 10 for shaft support is installed.

In addition, the bearing mounting hole 7a%8a of each case 7.8
are formed penetrating the inside and outside of the case, and the ball bearings 9.10 mounted in the bearing mounting holes 7a, 8a are exposed to the inside and outside of the case. Reference numeral 11 denotes a stator provided inside the motor case 6, and as shown in FIG. It is composed of a winding 13.

A rotor 14 is located inside the stator 11 and attached to the rotor shaft 15. The rotor shaft 15 is arranged on the central axis inside the motor case 6, and one end is rotatably supported by a ball bearing 9 attached to the front case 7, and the other end is attached to the rear case 8. It is rotatably supported by a ball bearing 10. A pair of retaining rings 16 and 17 are attached to the rotor shaft 15, one retaining ring 16 is in contact with the end surface of the inner ring of the ball bearing 9 on the rotor side, and the other retaining ring 17 is It is in contact with the end surface of the inner ring of the ball bearing 10 on the rotor side.

The rotor 14 has the configuration described below. That is,
As shown in FIG. 4, the rotor 14 includes a plurality of rotor elements 1.
Each rotor element 18 is composed of a permanent magnet 19 and a pair of yokes 20 and 20.

The permanent magnet 19 has a disk shape that is magnetized along the axial direction, and has a center hole 1 through which the rotor shaft 15 passes.
It has 9a. This permanent magnet 19 is made of a ferrite magnet or a rare earth magnet.

The pair of yokes 20.20 have the same structure in terms of size and shape. As shown in FIG. 3, these yokes 20.degree.
The yoke main portion 20a is integrally provided with an arcuate cover portion 20b extending substantially perpendicular to the yoke main portion 20a on a portion of the periphery of the yoke main portion 20a. A center hole 20c through which the rotor shaft 15 passes is formed in the center of the yoke main portion 20a. A circular protrusion 20d is integrally formed on the inner surface of each yoke main portion 20a, that is, on one side surface laminated to the permanent magnet 19. The inner diameter of this protrusion 20d is approximately equal to the diameter of the permanent magnet 19.
A side surface portion of the permanent magnet 19 is fitted onto the inner circumferential surface of d. The pair of yokes 20 are provided with yoke main portions 20a superimposed on both sides of the magnetized permanent magnet 19, so that the cover portion 20b faces the outer peripheral surface of the permanent magnet 19.
It is located covering a part of this outer peripheral surface.

The pair of yokes 20, 20 are laminated on both sides of the permanent magnet 19, with their cover portions 20b arranged point-symmetrically with respect to the rotor shaft 15, as shown in FIG. .

The even numbered sets of rotor elements 18 having the above configuration are attached to the rotor shaft 15 in a stacked manner. Moreover, these laminated layers are arranged in a line-symmetrical arrangement with respect to a line extending perpendicularly to the axis of the rotor shaft 15 as a reference line. That is, when the yokes 20.20 of different polarities are stacked on top of each other, the tips of the cover portions 20b of each yoke 20.20 are separated from each other by a slight gap. The rotor element 18 is fixed to the rotor shaft 15 by press-fitting the rotor shaft 15 into the center hole 19a to 20c. The rotor shaft 15 has a pair of adjusting members 2121 that are stacked on the yokes 20 located at both ends of the rotor shaft 15 and also serve as yokes.
is installed. These pair of adjustment members 21.21
is used for adjusting rotational imbalance, and has a shape that reduces rotational imbalance, for example, a ring shape. The adjustment member 21.21 is made of a non-magnetic material such as brass or stainless steel 5US303.

The blower fan 2 and fan cover 3 will be explained.

A blower fan 2 is arranged outside the end face of the front case 7 of the motor case 6, and the second blower fan 2 is attached to the front case 7.
The rotor shaft 15 is fitted onto the end of a rotor shaft 15 protruding from a bearing 9 provided in the shaft 15, and is fixed by screwing and tightening a sut 22 onto the end of the shaft 15. This blower fan 2 uses a centrifugal fan. An annular protrusion 23 is formed on the outer periphery of the end of the front case 7 so as to be located behind the blower fan 2 . A fan cover 3 is arranged and fixed on the outer periphery of the protrusion 23 to cover a portion other than the central portion of the blower fan 2 and an end surface portion of the front case 7. With these configurations, an air blowing section is constructed, with the central opening of the fan cover 3 facing the center of the front surface of the blowing fan 2 serving as the suction section 24, and the outer circumferential side serving as the blowing side.

The suction air path 4 and the conveyance roller 5 will be explained.

A cylindrical wall 25 is provided on the outer circumferential side of the motor case 6 to surround the entire case and constitute the air outlet path 5, and this wall 25 is attached to the motor case 6. On the outside of the wall 25, the rear case 8, and the fan cover 3, there is a wall shaped like a hammer that extends from the outside of the end face of the rear case 8 along the case axis direction and further reaches the outside of the end face of the front case 7. 26 is provided, and this wall 26 is attached to the wall 25, the rear cover 8 and the fan cover 3. The wall 25, the wall 26, the rear cover 8, and the fan cover 3 constitute a suction air path 4 that guides air outside the blower to the inside of the fan cover 3. This suction air passage 4 has a suction port 27 located on the outside of the end surface of the rear case 8 at one end, extends from the suction port 27 in the radial direction along the end surface of the rear case 8, and then extends through the wall 25. It extends in the axial direction of the case along the front case 7, and further extends in the radial direction along the end face of the front case 7, with the other end reaching the suction portion 24 of the fan cover 3. That is, this suction air passage 4 is one in which the air outside the blower flows from the end side of the motor case 6 opposite to the blower fan 2 toward the end side facing the blower fan 2 and guides it to the suction section 24. It is.

Here, a ball bearing 10 provided in the rear case 8 is provided in a portion extending in the radial direction along the end face of the rear case 8 located on the opposite end side of the blower fan 2 in the suction air path 4. exposed. That is, the ball bearing 10 is included in the middle of the suction air path 4. Therefore, during the process in which the air outside the blower is sucked into the suction air path 4 and guided toward the suction part 24, it comes into contact with the ball bearing 10 provided in the rear case 8 located on the opposite side of the blower fan 2. It will flow.

Further, the wall 25, the protruding portion 23 of the front case 7, and the rear case 8 constitute a cylindrical air passage 5 that surrounds the entire circumference of the motor case 6. A delivery port 28 is formed that faces the peripheral wall surface of the case 8 and opens. Projection 23 on the peripheral wall surface of the front case 7
A plurality of communication holes 29 that communicate the inside of the fan cover 3 and the inside of the motor case 6 are formed in a portion closer to the end face, distributed in the circumferential direction of the case. A plurality of communication holes 30 are formed in the protrusion 23 and are dispersed in the case circumferential direction to communicate the inside of the fan cover 3 and the inside of the air outlet path 5 . A plurality of communication holes 31 are formed in the peripheral wall surface of the rear case 8 and are distributed in the case circumferential direction to communicate the inside of the motor case 6 and the inside of the air outlet path 5 .

The blower configured in this manner blows air by driving the electric motor 1 and rotating the blower fan 2. That is, when the energization to the winding 13 of the stator 11 is controlled and the excitation phases of the winding 13 are sequentially switched, the rotor 14 is rotated by the magnetic circuit formed between the stator 11 and the rotor 14. It is something that makes you The rotation speed of the rotor 14 is, for example, 15.
000rp1 or more.

When the rotor 14 rotates, the rotor shaft 15 rotates, and the blowing fan 2 rotates together with the rotor shaft 15. As the blower fan 2 rotates, air outside the blower is sucked into the inside of the fan cover 3 from the suction air path 4, and further sent out to the outside of the blower through the delivery air path 5.

Air outside the blower is sucked into the outlet air path 4 through the suction port 27. The air flows through a portion extending in the radial direction along the end surface of the rear case 8 in the delivery air path 4, and then flows through the wall body 25.
It flows along a portion extending in the axial direction of the case, further flows through a portion extending in the radial direction along the edge of the front case 7, and is sucked into the suction portion 24 of the fan cover 3. Air is sucked in from the center of the rotating blower fan 2 and blown out from the outer periphery to the inner periphery of the fan cover 3. A part of the blown air directly enters the inside of the delivery air path 5 through each communication hole 30 formed in the protrusion 23 of the front case 7 of the motor case 6, and flows inside the delivery air path 5. It is sent out from the sending port 28.

In addition, another part of the blown air enters the inside of the motor case 6 through the communication hole 29 formed in the front case 7, flows inside the motor case 6 in the axial direction, and is formed in the rear case 8. It enters the delivery air path 5 through the communication hole 31 and is sent out from the delivery port 28.

Let's take a look at the state of heat dissipation and cooling in each part of this blower. First, the air flowing inside the suction air passage 4 comes into contact with the ball bearing 10 provided at the end face of the rear case 8 of the motor case 6, that is, at the end of the motor case 6 opposite to the blower fan 2. The ball bearing 10 is cooled down. Conventionally,
A ball bearing 10 for supporting the rotor shaft provided at the end of the rear case 8 of the motor case 6, that is, at the end of the motor case 6 opposite to the blower fan 2, is located away from the blower fan 2 and is not connected to the intake air. Without contact, the ball bearing 10 was heated by the heat of the stator 11 and its temperature rose significantly. In this embodiment, the air sucked in by the blower fan 2 contacts the ball bearing 10 provided on the end face of the rear case 8 before reaching the fan cover 31; A rise in temperature of the ball bearing 10 due to heat and heat generated due to friction with the rotor shaft 15 can be reliably suppressed. Therefore, it is possible to prevent the adverse effects of temperature rise on the ball bearing 10 and extend its life. In this embodiment, the suction port 27 is provided near the ball bearing 10,
The ball bearing 10 is effectively cooled with the air immediately after being sucked into the suction air path 4 from the suction port 27.

In addition, the ball bearing 9 provided on the end face of the front case 7 of the motor case 6 is cooled by the air sucked into the fan cover 3 by the blower fan 2 and the air flowing into the motor case 6, and is fixed. Ball bearing 10 due to the heat of child 11
temperature rise is suppressed. As the air blown out by the blower fan 2 flows inside the motor case 6, the stator 11 and the rotor] 4 provided inside the motor case 6 are cooled. The air blown out by the blowing fan 2 flows through the blowing air path 5, thereby cooling the motor case 6 and suppressing the rise in temperature of the motor case 6 due to heat generated by the stator 11.

Furthermore, in this embodiment each ball bearing 9.10 is connected to the stator 11.
Since it is provided at the end face portion of the motor case 6, which is the farthest position from the stator 11, the influence of the heat of the stator 11 is small.

Another embodiment will be described with reference to FIG.

This embodiment uses the rotor 1 in the blower shown in FIG.
A detection device for detecting the rotational position of 4 is provided inside the motor case 6, and the same parts are given the same reference numerals.

In FIG. 5, reference numeral 32 denotes a disk located at a position close to the end surface of the rear case 8 of the motor case 6, that is, the ball bearing 10.
The rotor shaft 1-r is fitted and fixed to the rotor shaft 15 at a position close to the rotor shaft 1-r. A plurality of magnetic poles 33 according to the specifications of the electric motor 1 are provided on the side surface of the disc 32 facing the end face of the rear case 8 and are distributed in the circumferential direction. At the center of the inner surface of the end surface of the rear case 8, a plurality of sensors 34 corresponding to the magnetic poles 33 of the disk 32 and in accordance with the specifications of the electric motor 1 are provided distributed in the circumferential direction. For example, a Hall element is used as this sensor 34. The disk 32 having these magnetic poles 33 and the sensor 34 constitute a detection device that detects the rotational position of the rotor 14. That is, the rotational position of the rotor 14 can be detected according to the signal from the sensor 34 that is output to the disk 32 as it rotates.

Based on this detection result, the rotor 14 can be rotated by controlling the current supply to the winding 13 of the stator 11.

In this embodiment, the detection device is provided at a location away from the stator 11, and the detection device is cooled by the air flowing inside the motor case 6, so that the temperature rise is small and malfunctions due to temperature rise are prevented. can do.

The blower of the present invention is used for sucking air into a vacuum cleaner, exhausting air from a combustion type heater, and the like.

Note that the present invention is not limited to the embodiments described above, and can be implemented with various modifications.

For example, the positional relationship between the ball bearing 10 and the suction air passage 4 is not limited to the example, and the suction port 27 may be provided at a position away from the ball bearing 10.

The configurations of the suction air path and the delivery air path are not limited to the embodiments.

The type of electric motor is not limited to that in the embodiment.

(Effects of the Invention) As explained above, according to the blower of the present invention, the bearing for supporting the rotor shaft provided at the end of the electric motor opposite to the blower fan is cooled by the air sucked in by the blower fan. Therefore, it is possible to suppress the temperature rise of the bearing, which has conventionally been located far from the blower fan and not come into contact with the intake air, and the temperature rise of the bearing is significant, and the life of the bearing can be improved by preventing the reduction in life due to heat.

[Brief explanation of the drawing]

Figures 1 to 4 show one embodiment of the present invention.
The figure is a sectional view showing a blower to which this invention is applied, Figure 2 is a plan view of the stator, Figure 3 is a side view of the rotor, Figure 4 is a partially exploded perspective view of the rotor, and Figure 5 is another embodiment. It is a sectional view of the blower in an example. 1...Electric motor, 2...Blower fan, 3...Fan cover, 4...Suction air path, 5...Output air path, 6...
Electric motor case, 11... stator, 14... rotor. Applicant's agent Patent attorney Takehiko Suzue Figure 2 6 - Denkoku Case 11/Details) 14. Rotation top Figure 1 Figure

Claims (1)

[Claims] an electric motor including a stator and a rotor provided inside a motor case, a rotor shaft supported by a bearing provided in the motor case and to which the rotor is attached; and one end of the motor with respect to the motor case. A blower comprising a blower fan provided on the side and rotated by the rotation of the rotor shaft, and a fan cover surrounding the blower fan, the blower having a suction port at one end, and the blower fan of the motor case having a suction port at one end. A blower characterized in that a suction air path is formed on the outside of the motor case, the bearing provided at the opposite end being included in the air path, and the other end communicating with the suction portion of the fan cover.