Patent US2888872A successfully refreshed from Google Patents.
US20030193260A1
Expired / Lapsed
US
⏱️ 0.0 years remaining
Composite power metal stator sleeve
Assignee: Delphi Technologies Inc
•
Filing: 2002-04-16
•
Granted: —
•
Expires: 2022-04-16
Abstract
Abstract A composite powder metal stator sleeve for placing adjacent the tip-less teeth of a conventional stator core to form a stator assembly in an electric machine. The sleeve includes alternating tooth tip-shaped magnetically conducting segments of sintered ferromagnetic powder metal and magnetically non-conducting segments of sintered non-ferromagnetic powder metal. A stator assembly is also provided in which a stator core, for example, of stamped laminations, includes radially extending tip-less teeth, and the composite sleeve of the present invention surrounds and contacts the teeth of the stator core to form tips extending from the teeth and topsticks/slot wedges between the tips. There is further provided alternative methods of making an annular composite powder metal stator sleeve of the present invention, including a compaction-sintering method, an injection molding method, and a sinterbonding method.
Inventors
- 👤 Frederick Reiter
- 👤 Brian Maskew
- 👤 Ronald Krefta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 01:19
CPC Classifications
H; H02; H02K; H02K1/00; H02K1/06; H02K1/12; H02K1/14; H02K1/146; H02K1/148; B; B22; B22F; B22F7/00; B22F7/06; B22F7/062; B22F7/064; H02K1/02; H02K1/16; H02K1/165; H02K15/00; H02K15/02; H02K5/00; H02K5/04; H02K5/12; H02K5/128
Claims Analysis
Total Claims: 50
Claim 1
Independent Claim
84 words
1 . An annular composite powder metal stator sleeve for placing over tipless teeth of an annular stator core, the sleeve comprising a plurality of magnetically conducting segments of sintered ferromagnetic powder metal in alternating relation with a plurality of magnetically non-conducting segments of sintered non-ferromagnetic powder metal to form the annular composite powder metal stator sleeve, wherein the magnetically conducting segments have a shape corresponding to a desired tooth tip-shape, for forming tooth tips when placed over the teeth of the stator core.
Claim 2
Dependent Claim
84 words
1 . An annular composite powder metal stator sleeve for placing over tipless teeth of an annular stator core, the sleeve comprising a plurality of magnetically conducting segments of sintered ferromagnetic powder metal in alternating relation with a plurality of magnetically non-conducting segments of sintered non-ferromagnetic powder metal to form the annular composite powder metal stator sleeve, wherein the magnetically conducting segments have a shape corresponding to a desired tooth tip-shape, for forming tooth tips when placed over the teeth of the stator core.
Claim 3
Dependent Claim
20 words
2 . The sleeve of claim 1 wherein the ferromagnetic powder metal is Ni, Fe, Co or an alloy thereof.
Claim 4
Dependent Claim
24 words
3 . The sleeve of claim 1 wherein the ferromagnetic powder metal is a high purity iron powder with a minor addition of phosphorus.
Claim 5
Dependent Claim
17 words
4 . The sleeve of claim 1 wherein the non-ferromagnetic powder metal is an austenitic stainless steel.
Claim 6
Dependent Claim
18 words
5 . The sleeve of claim 1 wherein the non-ferromagnetic powder metal is an AISI 8000 series steel.
Claim 7
Dependent Claim
96 words
6 . A powder metal stator assembly for an electric machine, comprising: a stator core comprising a back iron and a plurality of tip-less teeth extending radially therefrom; at least one composite powder metal sleeve over the teeth, the at least one sleeve comprising a plurality of magnetically conducting segments of sintered ferromagnetic powder metal in alternating relation with a plurality of magnetically non-conducting segments of sintered non-ferromagnetic powder metal, each magnetically conducting segment being generally aligned with a corresponding tooth of the stator core to thereby form tooth tips extending from the plurality of teeth.
Claim 8
Dependent Claim
96 words
6 . A powder metal stator assembly for an electric machine, comprising: a stator core comprising a back iron and a plurality of tip-less teeth extending radially therefrom; at least one composite powder metal sleeve over the teeth, the at least one sleeve comprising a plurality of magnetically conducting segments of sintered ferromagnetic powder metal in alternating relation with a plurality of magnetically non-conducting segments of sintered non-ferromagnetic powder metal, each magnetically conducting segment being generally aligned with a corresponding tooth of the stator core to thereby form tooth tips extending from the plurality of teeth.
Claim 9
Dependent Claim
20 words
7 . The assembly of claim 6 wherein the ferromagnetic powder metal is Ni, Fe, Co or an alloy thereof.
Claim 10
Dependent Claim
24 words
8 . The assembly of claim 6 wherein the ferromagnetic powder metal is a high purity iron powder with a minor addition of phosphorus.
Claim 11
Dependent Claim
17 words
9 . The assembly of claim 6 wherein the non-ferromagnetic powder metal is an austenitic stainless steel.
Claim 12
Dependent Claim
18 words
10 . The assembly of claim 6 wherein the non-ferromagnetic powder metal is an AISI 8000 series steel.
Claim 13
Dependent Claim
107 words
11 . A method of making an annular composite powder metal stator sleeve for placing over an annular stator core having a plurality of tip-less teeth, the sleeve comprising a plurality of tooth tip-shaped magnetically conducting segments in alternating relation with a plurality of magnetically non-conducting segments, the method comprising: placing a plurality of green-strength magnetically conducting segments adjacent a plurality of green-strength magnetically non-conducting segments in alternating relation to form a ring; adding powder metal between the segments; and sintering the segments and added powder metal whereby the segments are bonded together by the added powder metal to form the annular composite powder metal stator sleeve.
Claim 14
Dependent Claim
107 words
11 . A method of making an annular composite powder metal stator sleeve for placing over an annular stator core having a plurality of tip-less teeth, the sleeve comprising a plurality of tooth tip-shaped magnetically conducting segments in alternating relation with a plurality of magnetically non-conducting segments, the method comprising: placing a plurality of green-strength magnetically conducting segments adjacent a plurality of green-strength magnetically non-conducting segments in alternating relation to form a ring; adding powder metal between the segments; and sintering the segments and added powder metal whereby the segments are bonded together by the added powder metal to form the annular composite powder metal stator sleeve.
Claim 15
Dependent Claim
38 words
12 . The method of claim 11 further comprising forming the plurality of green-strength magnetically conducting segments by pressing a ferromagnetic powder metal and forming the plurality of green-strength magnetically non-conducting segments by pressing a non-ferromagnetic powder metal.
Claim 16
Dependent Claim
17 words
13 . The method of claim 12 wherein the added powder metal is the ferromagnetic powder metal.
Claim 17
Dependent Claim
17 words
14 . The method of claim 12 wherein the added powder metal is the non-ferromagnetic powder metal.
Claim 18
Dependent Claim
20 words
15 . The method of claim 12 wherein the ferromagnetic powder metal is Ni, Fe, Co or an alloy thereof.
Claim 19
Dependent Claim
24 words
16 . The method of claim 12 wherein the ferromagnetic powder metal is a high purity iron powder with a minor addition of phosphorus.
Claim 20
Dependent Claim
17 words
17 . The method of claim 12 wherein the non-ferromagnetic powder metal is an austenitic stainless steel.
Claim 21
Dependent Claim
18 words
18 . The method of claim 12 wherein the non-ferromagnetic powder metal is an AISI 8000 series steel.
Claim 22
Dependent Claim
17 words
19 . The method of claim 12 wherein pressing comprises uniaxially pressing the powder in a die.
Claim 23
Dependent Claim
17 words
20 . The method of claim 19 wherein pressing comprises pre-heating the powder and pre-heating the die.
Claim 24
Dependent Claim
17 words
21 . The method of claim 11 wherein the added powder metal comprises a magnetically conducting material.
Claim 25
Dependent Claim
17 words
22 . The method of claim 11 wherein the added powder metal comprises a magnetically non-conducting material.
Claim 26
Dependent Claim
36 words
23 . The method of claim 11 wherein sintering includes delubricating the segments by heating to a first temperature, followed by fully sintering the segments by heating to a second temperature greater than the first temperature.
Claim 27
Dependent Claim
61 words
24 . The method of claim 11 further comprising placing a plurality of the composite powder metal sleeves adjacent the stator core, with the magnetically conducting segments of the sleeves generally aligned with the respective tip-less teeth to form a plurality of tooth tips extending from the teeth of the stator core, to form a stator assembly for an electric machine.
Claim 28
Dependent Claim
118 words
25 . A method of making an annular composite powder metal stator sleeve for placing over an annular stator core having a plurality of tip-less teeth, the sleeve comprising a plurality of tooth tip-shaped magnetically conducting segments in alternating relation with a plurality of magnetically non-conducting segments, the method comprising: filling a plurality of first regions in a ring-shaped die with a ferromagnetic powder metal; filling a plurality of second regions in the die with a non-ferromagnetic powder metal, the second regions in alternating relation with the first regions; pressing the powders in the die to form a compacted powder metal ring; and sintering the compacted powder metal ring to form the annular composite powder metal stator sleeve.
Claim 29
Dependent Claim
118 words
25 . A method of making an annular composite powder metal stator sleeve for placing over an annular stator core having a plurality of tip-less teeth, the sleeve comprising a plurality of tooth tip-shaped magnetically conducting segments in alternating relation with a plurality of magnetically non-conducting segments, the method comprising: filling a plurality of first regions in a ring-shaped die with a ferromagnetic powder metal; filling a plurality of second regions in the die with a non-ferromagnetic powder metal, the second regions in alternating relation with the first regions; pressing the powders in the die to form a compacted powder metal ring; and sintering the compacted powder metal ring to form the annular composite powder metal stator sleeve.
Claim 30
Dependent Claim
16 words
26 . The method of claim 25 wherein the first and second regions are filled concurrently.
Claim 31
Dependent Claim
28 words
27 . The method of claim 25 wherein the first and second regions are filled sequentially with the powder metal being pressed and sintered after each filling step.
Claim 32
Dependent Claim
20 words
28 . The method of claim 25 wherein the ferromagnetic powder metal is Ni, Fe, Co or an alloy thereof.
Claim 33
Dependent Claim
24 words
29 . The method of claim 25 wherein the ferromagnetic powder metal is a high purity iron powder with a minor addition of phosphorus.
Claim 34
Dependent Claim
18 words
30 . The method of claim 25 , wherein the non-ferromagnetic powder metal is an austenitic stainless steel.
Claim 35
Dependent Claim
19 words
31 . The method of claim 25 , wherein the non-ferromagnetic powder metal is an AISI 8000 series steel.
Claim 36
Dependent Claim
19 words
32 . The method of claim 25 , wherein the pressing comprises uniaxially pressing the powders in the die.
Claim 37
Dependent Claim
19 words
33 . The method of claim 32 , wherein the pressing comprises pre-heating the powders and pre-heating the die.
Claim 38
Dependent Claim
35 words
34 . The method of claim 25 , wherein, after the pressing, the compacted powder metal ring is de-lubricated at a first temperature, followed by sintering at a second temperature greater than the first temperature.
Claim 39
Dependent Claim
61 words
35 . The method of claim 25 further comprising placing a plurality of the composite powder metal sleeves adjacent the stator core, with the magnetically conducting segments of the sleeves generally aligned with the respective tip-less teeth to form a plurality of tooth tips extending from the teeth of the stator core, to form a stator assembly for an electric machine.
Claim 40
Dependent Claim
139 words
36 . A method of making an annular composite powder metal stator sleeve for placing over an annular stator core having a plurality of tip-less teeth, the sleeve comprising a plurality of tooth tip-shaped magnetically conducting segments in alternating relation with a plurality of magnetically non-conducting segments, the method comprising: injecting a ferromagnetic powder material from a first injection unit under heat and pressure into a plurality of first mold cavities in a ring-shaped mold, and allowing the ferromagnetic material to solidify; injecting a non-ferromagnetic powder material from a second injection unit under heat and pressure into a plurality of second mold cavities in the mold, the second mold cavities in alternating relation with the first mold cavities, and allowing the non-ferromagnetic material to solidify to thereby produce a composite injection molded green-strength ring; and sintering the composite ring.
Claim 41
Dependent Claim
139 words
36 . A method of making an annular composite powder metal stator sleeve for placing over an annular stator core having a plurality of tip-less teeth, the sleeve comprising a plurality of tooth tip-shaped magnetically conducting segments in alternating relation with a plurality of magnetically non-conducting segments, the method comprising: injecting a ferromagnetic powder material from a first injection unit under heat and pressure into a plurality of first mold cavities in a ring-shaped mold, and allowing the ferromagnetic material to solidify; injecting a non-ferromagnetic powder material from a second injection unit under heat and pressure into a plurality of second mold cavities in the mold, the second mold cavities in alternating relation with the first mold cavities, and allowing the non-ferromagnetic material to solidify to thereby produce a composite injection molded green-strength ring; and sintering the composite ring.
Claim 42
Dependent Claim
37 words
37 . The method of claim 36 further comprising, prior to sintering, ejecting the green-strength ring from the mold and subjecting the green-strength ring to debinding to provide a composite ring that is essentially free of binder.
Claim 43
Dependent Claim
17 words
38 . The method of claim 36 wherein the ferromagnetic and non-ferromagnetic powder materials are injected concurrently.
Claim 44
Dependent Claim
17 words
39 . The method of claim 36 wherein the ferromagnetic and non-ferromagnetic powder materials are injected sequentially.
Claim 45
Dependent Claim
31 words
40 . The method of claim 36 , wherein the ferromagnetic powder material is a soft ferromagnetic powder metal selected from the group consisting of Ni, Fe, Co and alloys thereof.
Claim 46
Dependent Claim
27 words
41 . The method of claim 36 , wherein the ferromagnetic powder material is a soft ferromagnetic high purity iron powder with a minor addition of phosphorus.
Claim 47
Dependent Claim
18 words
42 . The method of claim 36 , wherein the non-ferromagnetic powder material is an austenitic stainless steel.
Claim 48
Dependent Claim
19 words
43 . The method of claim 36 , wherein the non-ferromagnetic powder material is an AISI 8000 series steel.
Claim 49
Dependent Claim
24 words
44 . The method of claim 36 , wherein the ferromagnetic and non-ferromagnetic powder materials are each combined with a binder prior to injecting.
Claim 50
Dependent Claim
61 words
45 . The method of claim 36 further comprising placing a plurality of the composite powder metal sleeves adjacent the stator core, with the magnetically conducting segments of the sleeves generally aligned with the respective tip-less teeth to form a plurality of tooth tips extending from the teeth of the stator core, to form a stator assembly for an electric machine.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.