JPS62203040A - Spin tester - Google Patents

Abstract

PURPOSE:To shorten the working time required for a test to a large extent, by forming the underside of the body to be tested mounted to the lower end of a drive member into an open structure and making the drive member rotatable mainly depending on inertia in a state not contacted with a bearing. CONSTITUTION:When the test of the durability and safety of the body 31 to be tested mounted to the lower end of a drive member 27 against high speed rotation is performed, the drive members 25, 27 extending to a vertical downward direction from a rotary drive source 22 are ready to largely swing by resonance at the time of rotation and, especially, the lower part of the vibration member 27 is ready to swing to a larger extent. However, because the rotor 44 mounted to the outer periphery of the lower end part of the drive member 27 is controlled in this posture by a magnetic bearing 45 so as to be always positioned at the center, the swinging of the drive members 25, 27 is perfectly suppressed and said drive members 25, 27 are rotated at a high speed in an accurate posture without contacting protective bearings 41, 43. Because the underside of the body 31 to be tested is formed into an open structure, the body 31 to be tested can be detached rapidly and easily.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a spin tester that performs a rotation test on a test object that rotates at high speed, such as a turbocharger.

<Conventional technology> Recently, the speed of rotating bodies such as automobile turbochargers has increased,
With the advent of ceramics, spin testers are becoming increasingly important in testing the durability and safety of these high-speed rotating bodies, especially when manufacturing such rotating bodies, which requires 100% inspection within the production line. In this case, it has become extremely important in determining the efficiency of the entire production line.

Conventionally, there is a spin tester shown in FIG. 3 as such a spin tester. This spin tester has vacuum chamber 1
An air turbine 3 as a rotational drive source is provided on the upper plate 2 of the
Compressed air is supplied to the air turbine 3 through a supply port 5 to rotate the air turbine rotor 6 at high speed. The air turbine rotor 6 is supported by angular ball bearings 8.8 at two upper and lower locations, and a spindle 7 is vertically mounted on the air turbine rotor 6. The lower end of the spindle 7 is fitted into a hole 11a at the upper end of the arbor Il, and is fixed to the arbor 11 with set screws 9 from three locations equally spaced on the circumference. The shaft 14 of the turbocharger 12 as a test object is screwed into the hole 11b at the lower end of the arbor II, and the turbocharger 2 is mounted thereon. A touchdown bearing 15 is arranged on the outer periphery of the axis I4° on the lower side of the turbocharger I2, while another touchdown bearing 17 is arranged on the outer periphery of the arbor 11 on the upper side of the turbocharger 12. The touchdown bearings t5, 17 are arranged, for example, by 0.5° with respect to the upper arbor 11 of the turbocharger 12 and the lower axis 14° of the turbocharger 12.
It has a radial clearance of ~0.7ml1. These touchdown bearings 15,17 do not directly support the shaft 14' of the turbocharger 12 and the arbor 2, but rather the spindle 7, the arbor 11 and the turbocharger! The amount of whirling when passing through the rotational speed range (critical speed range) where it whirls around due to resonance during rotation is shown by the broken line in Figure 4.
0.7 mm), and is provided on both upper and lower sides of the turbocharger 12 so as to be supported on both sides. Therefore, outside the critical speed range, the touchdown bearing 15.17 is not in contact with the arbor 11 and the shaft 14°. Note that the reason why the turbocharger 12 and the like are arranged in the vacuum chamber 1 is to reduce windage loss and accelerate the test object to a desired rotational speed.

Then, compressed air is supplied to the air turbine 3 from the air supply port 5, rotates the air turbine rotor 6, and connects the turbocharger 1 via the spindle 7 and arbor 11.
2, rotate the turbocharger 12 to a desired high speed range by rotating the turbocharger 12 through the critical speed range while preventing whirling with the touchdown bearing 15. Durability and safety against high-speed rotation of 12 are tested.

<Problems to be Solved by the Invention> However, in the conventional spin tester described above, when the turbocharger 12 passes through a critical speed on the way to a predetermined high speed, the spindle 7° arbor 11 and the turbocharger 12 When the shaft 14' causes a whirling phenomenon (a whirling phenomenon with a period of a fraction of the number of revolutions, that is, a whirl phenomenon), the shaft 14' of the arbor 11 and the turbocharger 12 hits the touchdown bearing 15.17 times. Since contact occurs, wear occurs at the contact portion, increasing the clearance bond, making it impossible to limit the whirling phenomenon described above, and reducing the life of the touchdown bearing 15, 17 due to repeated shocks at the time of contact. There is a problem. Therefore, in the vibration damping method using a touchdown bearing, from the viewpoint of contact wear and bearing life, when increasing the rotational speed of the test object as shown by the broken line in Fig. 5,
It is necessary to take a long time to pass through the critical speed range and to minimize the impact at the time of contact as much as possible. Therefore, it takes a considerable amount of time to reach the required test rotation speed, which is one reason why tests cannot be performed quickly.

In addition, in the above spin tester, the turbocharger 12
In order to limit the whirling of the turbocharger by supporting it on both sides, it is necessary to provide a lower housing 16 to which the lower touchdown bearing I5 is attached. Therefore, when replacing the turbocharger I2 that has been tested, the lower housing 16 must be removed. The turbocharger 12 must be removed from the Arno<-11, and the turbocharger 12 cannot be replaced quickly. Therefore, from the above, there is a problem in that the vibration damping method using the touchdown bearing does not allow quick testing.

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the use of a touchdown bearing and adopt another vibration damping means, thereby making it possible to quickly and easily test a test object.

<Means for Solving the Problems> In order to achieve the above object, as illustrated in FIG. A member 25, a drive member 27 which is rotatably attached to the drive member 25 and has the test object 31 attached to its lower end, and a rotor 44 which is attached to the outer periphery of the upper end of the drive member 27 are magnetically supported. A magnetic bearing 45 capable of controlling the attitude of the driving member 25.27, and a protective bearing having a clearance smaller than the clearance between the stator 45a and the rotor 44 of the magnetic bearing 45 and capable of supporting the driving member 25.27. 41 and 43, and the lower side of the test object 31 attached to the lower end of the drive member 27 has an open structure.

<Function> In the above configuration, when testing the durability and safety against high-speed rotation of the test object 31 attached to the lower end of the drive member 27, the drive members 25 and 27 extending vertically downward from the rotation drive source 22 are rotated. It tries to swing around a lot due to the resonance of the time, and the lower the drive member 27 is, the more it tries to swing around. However, since the rotor 44 attached to the outer periphery of the upper end of the drive member 27 is controlled in attitude so that it is always at the center position by the magnetic bearing 45, the drive members 25, 27 are completely prevented from whirling around, and the stator 45a, the protective bearing 41.4
3, it is rotated at high speed in the correct posture, that is, in the center position. Further, since the lower side of the test object 31 has an open structure, the test object 31 can be quickly and easily removed.

<Example> Hereinafter, the present invention will be explained in detail with reference to illustrated embodiments.

In FIG. 1, 21 is a vacuum chamber, and 22 is an air turbine as an example of a rotary drive source installed on the upper plate 23 of the vacuum chamber 21. In FIG. This air turbine 22 has the same structure as the conventional example, and houses an air turbine rotor (not shown).

This air turbine rotor is provided with a small diameter spindle 25 that is a driving member that extends vertically downward.

A vacuum seal 26 is fitted to the upper part of the spindle 25 and sealed at the lowest circumferential speed, thereby sealing the inside of the vacuum chamber 21 while increasing the durability of the vacuum seal.

A hole 27a at the upper end of the arbor 27, which is a driving section, is fitted into the lower end of the spindle 25. This arbor 27 is a stepped cylinder having a diameter larger than that of the spindle 25, and is composed of small diameter portions 27A, 27B, and 27G in order from the top. The spindle 25 and the arbor 27 are connected by screwing set screws 28, 28.28 from three locations equally spaced in the circumferential direction from the outer circumferential surface 27b of the small diameter portion 27A of the arbor 27 to the outer circumferential surface 25a of the spindle 25. Is going. The reason why the diameter of the arbor 27 is made larger as it goes downward is to make it easier to pull the arbor 27 downward and take it out. A hole (not shown) in the large diameter portion 27C at the lower end of the arbor 27 is provided with a turbocharger 3 as a test object.
The upper end of the turbocharger shaft 32, which is fitted through I, is screwed into the upper end. There is no member on the lower side of this turbocharger 31, and it has an open structure.

On the other hand, a cylindrical bracket 34 is arranged on the outer periphery of the spindle 25 with a space 33 therebetween.
4 to the lower surface 23a of the upper plate 23 of the vacuum chamber 21.
It is fixed at A working hole 35 is provided on the side surface of this bracket 34, and the set screw 2 is inserted through this working hole 35.
8, 28. Screw on or remove 28, and install spindle 2.
5 and the arbor 27 can be easily connected and removed. A thick cylindrical housing 3 into which an arbor 27 is inserted is inserted into the lower end of the bracket 34.
The upper ends of 6 are connected. A cylindrical support member 37 is attached to the lower end of this housing 36, and this support member 3
A protective bearing 4 is provided in the recess 62 at the lower end of the inner peripheral surface 37a of 7.
3 is attached and fixed from below by a holding member 38. The clearance between the protective bearing 43 and the outer peripheral surface of the large diameter portion 27G of the arbor 27 is set to 0.1 mm. In the recess 61 at the upper end of the inner circumferential surface 36a of the housing 36,
A protective bearing 41 is mounted and fixed by pressing the bearing 41 from above with a press plate 42. The clearance between this protective bearing 41 and the outer peripheral surface 27b of the arbor 27 is also 0.1
I'm making it into a dragon. A silicon steel laminated rotor 44 serving as a rotor is fitted into the middle diameter portion 27B of the arbor 27 between the two protection bearings 41, 43. Inner peripheral surface 3 of the housing 36 corresponding to this silicon steel plate laminated rotor 44
An electromagnetic stator 45a is attached to the recess 63 of the rotor 44 and the stator 45a to form a magnetic bearing 8. , at a position facing the silicon copper plate laminated rotor 44, the arbor 2
This system generates suction force in two mutually orthogonal axes directions perpendicular to the axis of 7, and controls its two degrees of freedom. The clearance between the silicon steel laminated rotor 44 and the electromagnetic stator 45a is set to 0.2 mm, which is larger than the 0.1 mm clearance of the touchdown bearing 41.43. In this way, the reason why the clearance between the silicon steel plate laminated rotor 44 and the electromagnetic stator 45a is made larger than the clearance between the protective bearings 41 and 43 is because the magnetic bearing 45 cannot prevent the whirling phenomenon when the arbor 27 rotates at high speed. In such a case, the arbor 27 is connected to the electromagnetic stator 45a.
This is to protect the magnetic bearing 45 by allowing the rotor 44 to come into contact with the protective bearings 41 and 43 more quickly and preventing the rotor 44 from coming into contact with the electromagnetic stator 45a. Further, two pairs of position detection sensors 51 . 51
, 51, 51 are provided. The position detection sensor 51 detects the displacement of the arbor 27 from the center position, the displacement signal is input to the calculation circuit 53, and the calculation circuit 53 compares and calculates the human input displacement signal with a predetermined reference signal.
The calculation result is sent to the electromagnet stator 4 via the driver 54.
5a, so that the electromagnetic stator 45a rotates the silicon steel laminated rotor 44 in its normal position, that is, at the center position.

In the above configuration, compressed air is supplied to the air turbine 22, and the spindle 25, arbor 27, and turbocharger 31 are rotated together.

At this time, since the inside of the vacuum chamber 21 is in a substantially vacuum state, the windage loss due to the rotation of the turbocharger 31 is reduced, and the turbocharger 31 is rapidly accelerated. When the speed reaches a critical speed, the arbor 27 causes a whirl phenomenon and tries to swing around. At this time, the sensor 51 detects the displacement of the arbor 27, and the arithmetic circuit 53 causes the current to flow through the driver 54 to the electromagnet stator 45a. Controlled silicon steel laminated rotor 4 with arbor 27
4 to return the arbor 27 to its center position, that is, to its normal posture. In other words, the whirl phenomenon is controlled. Therefore, the arbor 27 passes through the critical speed without contacting the magnetic bearing 45 and the protective bearings 41, 43, and after passing the critical speed, the turbocharger 31, the arbor 27, and the spindle 25 move due to the inherent self-alignment of the rotating body. , rotates around the center of inertia and reaches a predetermined high speed rotation range.

In this way, since the swing of the silicon steel laminated rotor 44 is controlled by the electromagnetic stator 45a, the rotating body does not come into contact with the bearings, as shown by the broken line in FIG. 4, and therefore, as shown by the solid line in FIG. The specified high-speed test rotation range can be reached in a short time.

The protective bearings 41 and 43 can also be switched to be lubricated with solid lubricant, and the vacuum chamber 2
It is possible to eliminate the use of a lubrication port in vacuum chamber 2.
Figure 2 shows another embodiment. This embodiment is applied when the arbor 27 is longer in the vertical direction than the width dimension of the magnetic bearing 45, and magnetic bearings 46 and 46 having the same configuration as the magnetic bearing 45 of the above-mentioned embodiment are moved vertically. This is because the protective bearings 41 and 43 are provided on two sides. The reason why the magnetic bearings 46 and 46 are provided at the upper and lower parts of the arbor 27 is as follows.
is long and the spindle 25 is thinner than the arbor 27, so the vibration damping force of the magnetic bearing 46 no longer contributes to the distribution of the joint between the spindle 25 and the arbor 27, causing whirling in the upper part of the arbor 27. It's for a reason. The rest of the structure and operation are exactly the same as those of the above-described embodiment, so their explanation will be omitted.

In the embodiment described above, the drive member is composed of a small diameter spindle 25 and a large diameter arbor 27, so that when an abnormality occurs due to damage to the test object, the spindle 25 is the weakest point and breaks. , the air turbine 22 will not be damaged.

In the above embodiment, the driving member is composed of a spindle and an arbor, but it may be an integral member. In addition, two protective bearings 4.1.43 are provided sandwiching the magnetic bearing 45 above the turbocharger 31, but it is also possible to use only one protective bearing, but the point is that as long as it is above the turbocharger 31 and can protect the magnetic bearing 45, good. Furthermore, a high frequency motor may be used as the rotational power source.

<Effects of the Invention> As is clear from the above description, the spin tester of the present invention includes a rotary power source, a drive member that extends vertically downward from the rotary power source and has a test object attached to its lower end, and a magnetic bearing that can magnetically support a rotor attached to a lower end of the member and control the attitude of the driving member; and a magnetic bearing having a clearance smaller than a clearance between the stator and rotor of the magnetic bearing, The device is equipped with a supportable protective bearing, and has an open structure on the lower side of the test object attached to the lower end of the drive member.

Therefore, according to the present invention, when the drive member rotates at a critical speed, the swing of the drive member is controlled by the magnetic bearing, and as shown in FIG. As shown in FIG. 5, the test object can reach a predetermined high-speed rotation range in a short time, and the working time required for testing can be significantly shortened.

Further, according to the present invention, the upper end of the driving member is attached to the rotational drive source, and the lower end of the driving member has an open structure below the test object, so that the driving member or the test object does not interfere with other members. It can be easily removed and installed without being damaged, improving test work efficiency, and in this respect also contributes to speeding up and efficiency of testing.

Furthermore, since both the magnetic bearing and the protective bearing can be made oil-free, contamination due to oil can be prevented.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention, FIG. 2 is a sectional view showing another embodiment, and FIG. 3 is a sectional view showing a conventional spin tester. FIG. 4 is a diagram showing the relationship between rotational speed and whirling amount, and FIG. 5 is a diagram showing the relationship between acceleration time and rotational speed. 22...Rotary power source, 25.27...Driving member, 3
1...Test object, 44...Rotor, 45.46...
・Magnetic bearing. Patent applicant: Koyo Seiko Co., Ltd.] Patent attorney: Mr. Said and 2 others

Claims (1)

[Claims] (1) A rotary power source, a drive member that extends vertically downward from the rotary power source and has a test object attached to its lower end, and a rotor that is attached to the lower end of the drive member and magnetically supports the rotor to drive the rotor. A magnetic bearing capable of controlling the posture of the member, and a protective bearing having a smaller clearance than the clearance between the stator and rotor of the magnetic bearing and capable of supporting the driving member, and attached to the lower end of the driving member. A spin tester characterized in that the lower side of the above-mentioned test object has an open structure.