JPS5875448A - Adjusting method for rotary balance of single bearing type motor - Google Patents

Abstract

PURPOSE:To adjust balance easily while preventing the deflection of a rotor by changing the depth of the lower hole of the innermost bottom of a tapped hole for mounting a load member formed along the circumferential direction of the end surface of the rotor. CONSTITUTION:With the rotor 2, a core 6 is unified through die casting molding while a plurality of the tapped holes 8 setting up the load member such as a fan 7 are bored to the end surface of the molding metallic member 6a at regular intervals along the circumferential direction. The lower holes 9 with diameters smaller than the diameters of the tapped holes 8 are bored up to predetermined depth in the innermost bottoms of each tapped hole 8. The bottom of the lower hole 9 of the tapped hole 8 of a section corresponding to the correction of imbalance is properly cut by using a cutting tool such as a drill, and balance is adjusted. Accordingly, rotary balance can easily be adjusted through a simple work, and the deflection of the rotor can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for adjusting the rotational balance of a single-bearing electric motor, which adjusts the rotational momentum of a rotor.

In general, single-bearing electric motors having a rotor and a bearing that supports one end of the rotor are widely used for lumberjack applications.

However, since this type of electric motor supports only the end of the rotor with a bearing, it suffers from the problem that vibrations tend to occur at the other end of the rotor, especially when the rotor rotates at high speed.

This invention was made with these points in mind, and its purpose is to provide a device that can adjust the rotational balance of the rotor and accurately correct rotor wobbling with simple operations. An object of the present invention is to provide a method for adjusting the rotational balance of a bearing type electric motor.

An embodiment of this invention will be described below with reference to all the drawings. Reference numeral 1 in FIG. 1 is the electric motor body, which is composed of (b) a rotor 2, a bearing 3 that supports it, and a stator 4 that concentrically surrounds the rotor 2. . The rotor 2 has a main body 2a formed by integrating a core 6 by die-casting and making the core ε bulge out toward one end surface side of the molded metal member 6a1, and a rotating shaft 5 passing through the center of the molded metal member 6a. and one end side of the rotating shaft 5 is a bearing 3.
Supported by Then, a plurality of screw holes 8 for attaching a load member such as a fan r are bored in the end face of the molded metal member 6a. As shown in FIG. 2, nine of these screw holes 8 are arranged at equal intervals along the circumferential direction on the end surface of the formed metal member 6a, and among these screw holes 8, for example, Three screw holes 8a divided equally in the direction...
- is for mounting the above fan 7, and the remaining screw holes 8b
... is provided for preliminary installation. In addition, at the deep bottom of each of the screw holes 8, as shown in FIG.
- is drilled to a predetermined depth. The stator 4 consists of a stator core 10 and a winding 11 wound around the stator core 10, and the winding 1 is covered by a winding cover 12. A housing 13 is provided on one side of the stator 4 to concentrically surround it. A cylindrical bearing support portion 14 is provided at the center of the how knob 13 by extending a portion thereof.

The above-mentioned cylindrical bearing 3 made of, for example, a porous sintered metal part is fitted into this support part 14 . On both end sides of the bearing 3, there are oil cores 15, which supply oil to the bearing 3.
16 have been erfed.

The end face kite-shaped metal J14 member 6a of the rotor 2 includes:
7 anchors 7 are provided, and the 7 anchors 7 are screwed into the 7 anchor mounting screw holes Jla, and are secured to the end surface by nine screws 11.

Next, (b) the procedure for adjusting the rotational balance of the trochanter 2 will be explained. For example, if the rotor 2 is shaken due to unbalanced weight of the fan 7, first stop the rotor 2, and then ...Remove J41 from the end face of the upper rotor 2. Next, move the fan 7 along the axis of rotation @6, remove the fan rtrab from the rotating shaft 5, and then place it on the end face of the rotor 2. The bottom surface of the pilot hole 9 of the screw hole 8 in a portion of the provided screw hole 8 that can correspond to the correction of the unbalance is appropriately cut using a cutting tool such as a drill to correct the unbalance. The division is removed, the weight distribution of the rotor 2 is changed, and the balance is '11114m.

After this, the fan 7t is reattached to its original position.

This maintains the overall balance of the rotor 2 and prevents it from wobbling during rotation.

on the other hand,? (by attaching and removing screw 17 when replacing anchor 10)
If the thread of the load member mounting screw hole 8a is damaged or the screw hole 8a becomes a blank hole, and it becomes impossible to mount the 7-an r in the screw hole 8a, first install the 7-an 1. Remove the screw 11 from the screw hole 81 for attaching the load member, which is impossible, and make the fan 1 slidable in the circumferential direction of the rotating shaft 5. 1 along the local direction of the rotating shaft 5, and align them with the preliminary mounting screw holes 8b and the mounting hole of the fan i shown in FIG. -t, then screw the screws 11 into the preliminary mounting screw holes 8 to fix the fan 1.

In this way, the present invention corrects the unbalance of the rotational balance of the rotor 2 by changing the depth of the pilot hole 9) and normalizes the rotational balance. is. The pilot hole 9 is provided as an escape area for cutting tools such as tags when forming the screw holes 8. This is used as a means for adjusting the 20-turn para/s't-11, so that the pilot hole 9 can be used effectively. Roughly nine screw holes 8 and pilot holes 9 are formed on the end surface of the rotor 20, which reduces the weight of the rotor 21 and reduces the mechanical strength of the rotor 20. This can reduce physical losses.

Note that this invention is not limited to the above-mentioned boundary layer side; for example, in the above-mentioned embodiment, the mounting screw hole t
- Three and six preliminary mounting screw holes are used, but it goes without saying that these mtt may be increased or decreased, and furthermore, the preliminary mounting screw holes are not necessarily required.

As explained above, according to the present invention, it is possible to easily adjust the rotational balance and prevent rotor wobbling by simply changing the depth of the pilot hole in the load member mounting screw hole. This effect is achieved.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, with Fig. 1 being a sectional view of a single bearing type electric motor, and Fig. M2 being a plan view of the end face of the 1g1 trochanter.
, FIG. 3 is a sectional view of the screw hole. 1.-Electric motor body, 2.-rotor, 4... stator, 8
a...Screw hole for mounting load member, 8b...Screw hole for preliminary mounting, +□9...Preparation hole. Applicant's attorney Takeshi Suzue Teeth 1 figure 2 figure 203-

Claims (1)

[Claims] A plurality of screw holes for attaching load members are formed along the circumferential direction at the end of the rotor, and pilot holes smaller than the diameter of each screw hole are formed at the center bottom of each of these screw holes. 11. A method for adjusting the rotational balance of a nine-piece bearing type electric motor, characterized in that the rotational panance of the rotor is adjusted by changing the depth of these pilot holes.