US4076197A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Torsional vibration isolating motor mounting arrangement and method of making the same
Assignee: General Electric Co
•
Filing: 1976-06-18
•
Granted: 1978-02-28
•
Expires: 1996-06-18
Abstract
Abstract Motor mounting system is designed so that the torsional mode resonant or natural frequency is less than twice the frequency of the motor power supply divided by the square root of two (√2). The illustrated mounting arrangements are "soft" with respect to torsional mode vibrations, and yet are "stiff" with respect to axial and tilting mode vibrations. In one arrangement, lugs are formed preferably from a tough and strong sheet or strip material with means which may be in the form of tuning apertures being provided for promoting flexure without objectably compromising lug strength for axial loading and with the tuning means preferably selected so that the cumulative effective spring constant of the mounting lugs will be less than the quantity (2.84×Ip×10 5 ). Also illustrated are mounting band members and torsionally flexible arms that interfit one with another in a slotted interrelationship so as to assure motor support and minimize the degree of weld or other fastener strength that would otherwise have to be provided between the arms and motor.
Inventors
- 👤 Richard W. Dochterman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 11:39
CPC Classifications
H; H02; H02K; H02K5/00; B; B60; B60H; B60H1/00; B60H1/00457; B60H1/00464; H02K5/24
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
112 words
A torsional mode vibration isolating mounting arrangement for an alternating current induction motor designed for excitation by an alternating voltage of a predetermined source frequency, and wherein said motor has a polar moment of inertia Ip, measured in pound-inches-seconds 2 , said mounting arrangement including a plurality of arms, formed from flat sheet material, extending radially from the motor and each having at least one tuning aperture formed therein with each aperture lying generally along a different generally radially extending plane; said tuning apertures being sized and located so that the cumulative effective spring constant, in pound-inches per radian will be less than the quantity 2.84 × Ip × 10 5 .
Claim 2
Dependent Claim
112 words
A torsional mode vibration isolating mounting arrangement for an alternating current induction motor designed for excitation by an alternating voltage of a predetermined source frequency, and wherein said motor has a polar moment of inertia Ip, measured in pound-inches-seconds 2 , said mounting arrangement including a plurality of arms, formed from flat sheet material, extending radially from the motor and each having at least one tuning aperture formed therein with each aperture lying generally along a different generally radially extending plane; said tuning apertures being sized and located so that the cumulative effective spring constant, in pound-inches per radian will be less than the quantity 2.84 × Ip × 10 5 .
Claim 3
Dependent Claim
65 words
The invention of claim 1 wherein the arms are dimensioned so that the cumulative effective spring constant thereof would be at least equal to 2.84 × Ip × 10 5 when no material is removed therefrom to provide tuning apertures, and wherein the ratio of twice the source frequency to the resonant frequency of the mounting system is greater than the square root of two.
Claim 4
Dependent Claim
52 words
The invention of claim 1 wherein each of the generally radially extending planes contain a longitudinally extending neutral axis and the tuning apertures are each generally symmetrical about one of the neutral axes, whereby the apertures in the arms do not substantially reduce the strength of the arms in the axial direction.
Claim 5
Dependent Claim
32 words
The invention of claim 1 wherein each of the arms has a tuning aperture located therein along the region of the arm subject to maximum deflection caused by torsional mode motor vibrations.
Claim 6
Dependent Claim
22 words
The invention of claim 1 wherein the arms each have a motor end thereof tightly trapped against the motor by band means.
Claim 7
Dependent Claim
19 words
The invention of claim 5 wherein the band means and arms inter-fit, one with another, in a slotted arrangement.
Claim 8
Dependent Claim
18 words
The invention of claim 6 wherein the motor ends of the arms are fastened to the band means.
Claim 9
Dependent Claim
40 words
The invention of claim 7 wherein the motor ends of the arms are welded to the band means, and the tightly trapped condition of the motor ends relieves the stress on the fastened interconnection of the band means and arms.
Claim 10
Dependent Claim
137 words
A torsionally flexible mounting system for an induction motor comprising a band member and a plurality of flexible arms; said flexible arms each inter-fitting with the band member in a slotted arrangement and having a motor end lying against an internal circumferential portion of the band member; said flexible arms being made of martensitic steel and having the extremity thereof at the motor end tack welded to the band member at at least one weld location on each motor arm, with the structural characteristics of the martensitic steel at each weld location degraded as a result of such weld; said band member tightly trapping the motor ends of the flexible arms flat against the motor whereby the structural integrity of the mounting system is assured notwithstanding the weld associated degradation of the arms at said weld locations.
Claim 11
Dependent Claim
137 words
A torsionally flexible mounting system for an induction motor comprising a band member and a plurality of flexible arms; said flexible arms each inter-fitting with the band member in a slotted arrangement and having a motor end lying against an internal circumferential portion of the band member; said flexible arms being made of martensitic steel and having the extremity thereof at the motor end tack welded to the band member at at least one weld location on each motor arm, with the structural characteristics of the martensitic steel at each weld location degraded as a result of such weld; said band member tightly trapping the motor ends of the flexible arms flat against the motor whereby the structural integrity of the mounting system is assured notwithstanding the weld associated degradation of the arms at said weld locations.
Claim 12
Dependent Claim
48 words
The invention of claim 9 wherein the motor has a polar moment of inertia Ip measured in pound-inches-seconds 2 , and the flexible arms establish a system having a cumulative effective spring constant, in pound-inches per radian, less than the quantity 2.84 × Ip × 10 5 .
Claim 13
Dependent Claim
113 words
A mounting arrangement for a motor comprising a band member for extending about an outer peripheral surface of a motor, and a plurality of mounting arms each having a motor end trapped between the outer peripheral surface of the motor and an inner peripheral surface of the band member; and wherein said band member has slots formed therein, the mounting arms each are bent and have an end thereof extending through a slot in the band member, and wherein each mounting arm is provided with tuning apertures in order to promote the deflection thereof in response to torsional mode motor vibrations and thereby reduce the transmissibility of torsional mode vibrations from the motor.
Claim 14
Dependent Claim
113 words
A mounting arrangement for a motor comprising a band member for extending about an outer peripheral surface of a motor, and a plurality of mounting arms each having a motor end trapped between the outer peripheral surface of the motor and an inner peripheral surface of the band member; and wherein said band member has slots formed therein, the mounting arms each are bent and have an end thereof extending through a slot in the band member, and wherein each mounting arm is provided with tuning apertures in order to promote the deflection thereof in response to torsional mode motor vibrations and thereby reduce the transmissibility of torsional mode vibrations from the motor.
References Cited (Backward Citations)
US2731193A
Cited
US2976352A
Cited
US2977043A
Cited
US3059250A
Cited
DE1135085B
Cited
US3145910A
Cited
US3317124A
Cited
US3584469A
Cited
US3746894A
Cited
US3790114A
Cited
US3773285A
Cited
US3830595A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-02-27 | 1981-08-29 | 1982-02-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-27 | 1985-08-29 | 1986-02-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-27 | 1989-08-29 | 1990-02-28 | $7700.00 | Window Closed / Lapsed |