GB2517457A

GB2517457A - Enclosure for electric motor

Info

Publication number: GB2517457A
Application number: GB201314924A
Authority: GB
Inventors: Michael Carmody
Original assignee: Pyroban Ltd
Current assignee: Pyroban Ltd
Priority date: 2013-08-21
Filing date: 2013-08-21
Publication date: 2015-02-25
Anticipated expiration: 2033-08-21
Also published as: GB201314924D0; WO2015025137A3; GB2517457B; WO2015025137A2

Abstract

The enclosure includes a housing 102 formed from a first plate member 106 defining a cavity 104 therein. The enclosure includes a second plate member 136 attached to the first plate member to seal the cavity at the first end and a ledge member 140 attached to the first plate member at the second end. A flange plate 144 detachably attached to the ledge member 140, the flange plate 144 being configured to support the drive end frame 206 of an electric starter motor 202 within the cavity, the flange plate and the ledge member defining a flame-path. The housing carries cable gland receiving bosses 130 and the flange plate an adapter nose cone 236 which surrounds the drive pinion gear 224 with a brass sleeve 238 between the cone and the gear. Threaded flame-paths are present between the bosses and cable glands, the ledge and flange members, and the frame and flange members. Additionally ground flame-paths are associated with the frame and flange members interface. A further flame-path is established between the between the pinion gear224 and the sleeve 238.

Description

ENCLOSURE FOR ELECTRIC MOTOR

Technical Field

10001] The present disclosure relates to a starter motor assembly, and more particularly to an enclosure for an electric motor of the starter motor assembly.

Background

10002] A typical hazardous environment may include a higher concentration of flammaNe gases or vapors as compared to normal environmental conditions.

Further, in the hazardous environment, flammable gases or vapors are expected to be present for long periods of time under normal operating conditions. Few examples locations having a hazardous environment includes oil, mining industry, marine applications, chemical industry and the like.

10003] Electric machines are frequently employed in these locations. During operation, electric machines may get overheated or issue sparks, which when exposed to the hazardous environment may lead to igniting a flame or drawing an arc above ignition temperatures of the flammable gases, and in few cases this may cause an explosion. Electric machines of this nature frequently include circuit breakers and starter motors.

10004] PCT Publication No. 2010,112,45 1 discloses a container for electric and/or dectronic devices for being used in potentially hazardous environments.

The container includes a base and one or more side walls joined to the base, so as to define an upper opening which can be closed by a cover and is surrounded by a first flange provided with a plurality of first holes, while the cover is provided with a second flange provided with a plurality of second holes corresponding to the first holes of the first flange, wherein the base, the side walls and the first flange are made of a single metal piece and the cover is joined to the container by means of one or more hinges which allow a rotating and translatory movement of the cover with respect to the container, the cover being provided with a perimetric frame suitable for penetrating into the upper opening; and for being coupled with the upper portion of the inner surfaces of the side walls.

Summary

100051 In one aspect, the present disclosure provides an enclosure for an electric motor. The enclosure includes a housing formed from a first plate mcmbcr. Thc housing defines a cavity thcrcin. Thc enclosure includes a first cnd and a sccond end disposed along a longitudinal axis of the cavity. The enclosure includes a second plate member attached to the first plate member to seal the cavity at the first end. The enclosure farther includes a ledge member attached to the first plate member at the second end. The enclosure further includes a flange plate detachably attached to the ledge member. The flange plate is configured to support the electric motor within the cavity. The flange plate and the ledge member define a flame-path.

10006] In another aspect, the present disclosure provides a starter motor assembly. The starter motor assembly includes an electric motor. The electric motor includes a driven end frame. A drive shaft extends through the driven end frame. The electric motor includes an adapter nose cone partly shielding a pinion gear attached at a distal cnd of thc drivc shaft. A sleeve mcmbcr is disposcd between the adapter nose cone and the pinion gear. The starter motor assembly further includes an enclosure. The enclosure includes a housing formed from a first plate member. The housing defines a cavity therein. The enclosure includes a first end and a second end disposed along a longitudinal axis of the cavity. The enclosure includes a second plate member attached to the first plate member to seal the cavity at the first end. The enclosure further includes a ledge member attached to the first plate member at the second end. The enclosure further includes a flange plate detachably attached to the ledge member. The flange plate is configured to support the electric motor within the cavity. The flange plate and the ledge member define a flame-path.

10007] In another aspect, the present disclosure provides a method of enclosing an electric motor in an enclosure. The method includes attaching a flange plate to a driven end frame of the electric motor. The method includes receiving an adapter nose cone of the electric motor through a shaft opening in the flange plate. The method includes placing the electric motor within a cavity defined by the enclosure. The method includes attaching the flange plate to a ledge member provided on the enclosure and defining a flame-path when the flange plate is attached to the ledge member.

100081 Other features and aspects of this disclosure will be apparent from the following description and the accompanying drawings.

Brief Description of the Drawings

100091 FIG. 1 illustrates a perspective view of an enclosure for an electric motor, according to an aspect of the present disc losure 100101 FIG. 2 illustrates a cross-sectional view of a starter motor assembly housed within the enclosure of FIG. 1; 100111 FIG. 3 illustrates a detailed view of a portion of FIG 2; 100121 FIG. 4 illustrates another detailed view of a portion of FIG 2; 100131 FIG. 5 illustrates another detailed view ofa portion of FIG 2; 100141 FIG. 6 illustrates yet another detailed view of a portion of FIG 2; and 100151 FIG. 7 is a flowchart for a method of enclosing the electric motor in the enclosure, according to an embodiment of the present disclosure.

Detailed Description

100161 The present disclosure relates to an enclosure for an electric motor.

FIG. I illustrates a perspective view of an enclosure 100, according to an aspect of the present disclosure. The enclosure 100 includes a housing 102 to define a cavity 104 therein. In an embodiment, the housing 102 may be formed from a first plate member 106, having a first thickness TI, by continuously bending and welding along lateral edges 108 of the first plate member 106 to form the cavity 104. The first plate member 106 may be submitted continuous bending operations at multiple positions to form a curved bottom surface 110, two inclined side surfaces 112 extending upward from the bottom surface 110, and a substantially flat top surface 114 formed by interconnecting the side surfaces 112 along the lateral edges 108. However, in alternative embodiments, the first plate member 106 may be bent to provide the enclosure 100 of any suitable shape and appearance based upon application andior design requirements.

100171 The enclosure 100 includes a first end 116 and a second end 118 disposed along a longitudinal axis AK of the cavity 104. According to an embodiment, a support member 120 is provided between the first end 116 and the second end 118. The support member 120 includes a transverse section 122 attached to the top surface 114 of the housing 102, and two legs 124 (only one leg is shown) extending downward from the transverse section 122 along the side surfaces 112 of the housing 102. The transverse section 122 and the legs 124 are attached to the first plate member 106 by welding. Further, the support member includes a gripping portion 126 extending upward from the transverse section 122. Moreover, the enclosure 100 includes a cable entry arrangement 128 including a one or more bosscd holes 130 providcd on at least onc of the side surface 112. The bossed holes 130 may have internal threads and configured to receive a cable gland to attach and secure electric cables (not shown) to the enclosure 100. It will be apparent to a person having ordinary skill in the art that the the bossed holes 130 may have similar or different construction.

100181 A second plate member 132, having a second thickness T2, is attached to a rear edge 134 of the first plate member 106 by welding and seals the cavity 104 at the first end 116 of the enclosure 100. According to an embodiment of the present disclosure, the first plate member 106 and the second plate member 132 are made to partly divide the cavity 104 into an upper compartment 136 and a lower compartment 138. In an embodiment, the cable entry arrangement 128 may include the respective bossed holes 130 corresponding to the upper compartmcnt 136 and the lower compartmcnt 138. The enclosure 100 may further include a ledge member 140, having a third thickness T3, is attached to a front edge 142 of the first plate member 106 at the second end 118 of the housing 102 by welding.

100191 In an aspect of present disclosure, the first plate member 106, the second plate member 132, and the ledge member 140 may be made from mild steel plates. Moreover, in an embodiment, the first thickness TI and thc second thickness T2 arc in a range of about 5mm to 10mm, and the third thickness T3 is in a range of about 10mm to 20mm. Further, the support member 120 is also made of a mild steel plate having a thickness in a range of about 5mm to 10mm.

It should be appreciated that the material and the sizes are design and application specific and may vary based upon different design and application requirements.

100201 According to an aspect of the present disclosure, a flange plate 144 is provided, which is configured to detachably attach to the ledge member 140 of the enclosure 100. In an aspect of the present disclosure, the flange plate 144 may have a fourth thickness T4 greater than the third thicknesses 13. As illustrated in FIG. 1, the ledge member 140 and the flange plate 144 are provided with a plurality of aligned first set of threaded openings 146 to receive respective a first set of threaded fasteners 148. Further, the flange plate 144 is provided with a shaft opening 150, and a protruding collar 152 surrounding the shaft opcning 150. A second sct of threaded openings 154 arc providcd on thc protruding collar 152, which will be explained further in conjunction with FIG. 2.

100211 According to an aspect of the present disclosure, a cross-sectional view of an exemplary starter motor assembly 200 using the enclosure 100 of FIG. 1 is illustrated in FIG. 2. In an embodiment, the starter motor assembly 200 may be a pre-engaged type starter motor assembly used to rotate an internal-combustion engine to initiate the engine's operation. The starter motor assembly includes an electric motor 202 housed within the cavity 104 and includes a motor casing 204. The motor casing 204 may include a drive end frame 206 and an end cap 208 that supports, along with many other components, an armature 210, a commutator 212 attached to the armature 210, a drive shaft 214 attached to the armature 210 and extending through the drive end frame 206, field coils 216 disposcd around the armature 210, and a pair of brushes 218 that bears upon thc commutator 212. A pinion assembly 220 is attached at a distal end 222 of the drive shaft 214, the pinion assembly 220 includes a pinion gear 224 and a spline 226 to slidably support the pinion gear 224. During operation, the pinion gear 224 is configured to slide on the spline 226 along an axis XX' of the drive shaft 214 by a pre-determined distance to engage with an engine ring gear (not shown).

An actuation arm 228 is provided to translate a linear movement associated with a plunger 230 of a solenoid 232 into the sliding movement of the pinion gear 224 along the drive shaft 214. The solenoid 232 is also partly supported by the drive end frame 206 and a solenoid end cap 233.

100221 In the illustrated embodiment, the solenoid 232 and the electric motor 202 are disposed in the upper compartment 136 and the lower compartment 138 of the cavity 104, respectively. According to an aspect of the present disclosure, the electric motor 202 is supported within the cavity 104 by the flange plate 144.

According to an aspect of the present disclosure, to accommodate the starter motor assembly 200 within the enclosure 100, a housing flange of the electric motor 202 is replaced with the flange plate 144 having a profile to conjugate the profile of the ledge member 140. Upon placing the starter motor assembly 200 within the enclosure 100, the flange plate 144 abuts the ledge member 140 of the enclosure 100.

100231 In an cxcmplary embodiment, the drive end frame 206 is rigidly attached with the flange plate 144 using a second set of threaded fasteners 234 fastened in the second set of openings 154 provided on the protruding collar 152 of the flange plate 144. Further, an adapter nose cone 236 is provided to partly shield the pinion assembly 220 and support the distal end 222 of the drive shaft 214. The adapter nose cone 236 is disposed in the shaft opening 150 provided in the flange plate 144. Moreover, a sleeve member 238 is disposed between the adapter nose cone 236 and the pinion gear 224. The sleeve member 238 may be made from brass.

100241 As described above, the bossed holes 130 provided on the enclosure 100, these bossed holes 130 allow the electrical cables to electrically couple the solenoid 232 and the electric motor 202 to an energy storage device, for example a battery. According to an embodiment, the internal threads in the bossed holes with a cable gland received therein define a first flame-path FPI. The first flame-path FF1 is a threaded flame-path. The threaded flame-path is configured to cool hot gases and/or a flame travelling from inside the enclosure 100 to outside. The hot gases travel along a threaded profile of the bossed holes 130 to cool off before escaping out of the enclosure 100. In an embodiment, the cable gland may be a ©TECEx (International Electrotechnical Commission) Triple Certified Flameproof (Typc-d), Increased Safety (Type-c) and Restricted Breathing (Type-nR) cable gland for use in Zone 1 areas providing a flameproof seal and environmental seal to the electrical cables. In alternative embodiments, the cable gland may be any (cIECEx Certified cable gland having a threaded flame-path.

100251 FIG. 3 illustrates a detailed view of the pinion assembly 220 of FIG. 2. According to an aspect of the present disclosure, the sleeve member 238 and the pinion gear 224 defines a second flame-path FP2 therebetween. The second flame-path FP2 is a cylindrical flame-path. According to an embodiment, the second flame-path FP2 having a diametrical gap Di which may be determined using International Standard 60079-1 of ©IEC. According to International Standard 60079-1, the diametrical gap Dl of the second flame-path FP2 is based upon a length LI of the second flame-path FP2 for a given volume of the enclosure 100. As illustrated, the length Li of the second flame-path FP2 is substantially equal to an axial length of the sleeve member 238.

100261 In an exemplary embodiment, referring to International Standard 60079-1 of ©IEC, the maximum diametrical gap DI for the length LI of the second flame-path FP2 may be selected from table 1 provided below. Table 1 refers to International Standard 60079-1 of ©IEC for a cylindrical joint for shaft glands or rotation electrical machines with a sleeve bearing when a volume of the enclosure 100 greater than 2000 em3 for use in a Group-I, Group -IIA, and Group-IIB type application. In the exemplary embodiment, for the enclosure 100 having the volume greater than 2000 cm3 and designed for Zone-I type environment and the length LI of the second flame-path FP2 is about 50 mm.

Further, the length LI of the second flame-path FP2 is configured to reduce to about 40 mmm when the pinion gear 224 engages with the engine ring gear.

Therefore, referring to table 1, the maximum diametrical gap Di allowed is close to 0.50 mm. In an aspect of the present disclosure, the maximum diametrical gap DI is kept about 0.40 mm, which is below the allowed maximum diametrical gap Dl of 0.50 mm, to design the second flame-path FP2 in accordance with International Standard 60079-I of@)IEC.

TABLE 1:

Mm. length L Maximum diametrical gap Dl Type ofjoint of the flame-(mm) path (mm) For a volume (cm) V>2000 Group Group Group I hA JIB Cylindrical 9.5 joints for shaft 12.5 0.40 0.20 glands of Sleeve rotating bearings 0.50 0.40 0.20 electrical machincs 0.60 0.50 0.25 with: 100271 FIG. 4 illustrates another detailed view of a portion of FIG. 2, where the drive end frame 206 is rigidly attached with the flange plate 144 using the second set of threaded fasteners 234. The second set of threaded fasteners 234 fastened in the second set of openings 154 defines a third flame-path FP3 therebetween. The third flame-path FP3 is a threaded flame-path. According to an embodiment, the third flame-path FP3 having a dia.metrica.l gap D2 which may also be determined using International Standard 60079-1 of ©IEC. According to International Standard 60079-1, the diametrical gap D2 of the third flame-path FP3 is based upon a length L2 of the third flame-path FP3 for a given volume of the enclosure 100. As illustrated, the length L2 of the third flame-path FP3 is substantially equal to a distance from inside of the enclosure 100 to an edge of thc sccond set of openings 154 on thc outside. According to an embodiment of the present disclosure, the diametrical gap D2 is kept about 0.30 mm as per the International Standard 60079-1 of ©IEC for a given length L2 of the third flame-path FP3.

100281 FIG. 5 illustrates another detailed view of a portion of FIG. 2, where the flange plate 144 is attached to the ledge member 140 using the first set of threaded fasteners 148 received in the first set of threaded openings 146. The flange plate 144 and the ledge member 140 abut to define a fourth flame-path FP4. The fourth flame-path FP4 includes a ground flame-path and a threaded flame-path. As shown in FIG. 5, the hot gases travel along an abutting surface 240 of the ledge member 130, and the flange plate 144 to define a ground flame-path. The hot gases then travel along the threaded fasteners 148 to define a threaded flame-path. According to an embodiment, the fourth flame-path FP4 having gap D30 and D31 which may also be determined using International Standard 60079-1 of ©IEC. According to International Standard 60079-1, gap D30 and D31 of the fourth flame-path FP4 are based upon length L30 and L31 of the ground flame-path and the threaded flame-path respectively for a given volume of the enclosure 100. As illustrated, the length L30 of the fourth flame-path FP4 is substantially equal to a distance from inside of the enclosure 100 to the threaded fastener 148 along the abutting surface 240. The length L31 of the fourth flame-path FP4 is substantially equal to the thickness T4 of the flange plate 144.

100291 FIG. 6 illustrates yet another detailed view of a portion of FIG. 2, where the flange plate 144 is attached to the ledge member 140. The flange plate 144 and the ledge member 140 abut to define a fifth flame-path FP5. The fifth flame-path FP5 is a ground flame-path and is defined along the abutting surface 240 of the ledge member 140 and the flange plate 144. According to an embodiment, the fifth flame-path FP5 having a gap D4 which may also be determined using International Standard 60079-1 of ©IEC. According to International Standard 60079-1, the gap D4 of the fifth flame-path FP5 is based upon a length L4 of the fifth flame-path FP5 for a given volume of the enclosure 100. As illustrated, the length L4 of the fifth flame-path FPS is substantially equal to a distance from inside of the enclosure 100 to an edge of the ledge member 140 on the outside.

Industrial Applicability

100301 A Zone I environment is defined as a location where concentration of flammable gases or vapors is higher as compared to normal environmental conditions. Further, in Zone I, flammable gases or vapors are expected to be present for long periods of time under normal operating conditions. A typical Zone I type environment will be an oil, mining industry, oil purification and processing industry, an industry manufacturing chemicals and the like. Electrical machine, such as the electric motor 202, installed in such locations are required to be housed in explosion proof and/or flame proof enclosures, such as the enclosure of the present disclosure. The enclosure 100 ensures that the electrical machine does not ignite an explosion due to arcing contacts or high temperature generated due to continued operation over a long period of time.

100311 The electric motor 202 under operation in Zone I type environment may generate sparks which may lead to ignition of the flammable gases present in the environment. Further, due to arcing contacts of the electric motor 202 and presence of flammable gasses in the environment, the enclosure 100 experiences internal explosions. According to an embodiment of the present disclosure, thc enclosure 100 is made of mild steel. However in alternative embodiments, thc enclosure 100 may be made of any suitable material having strength enough to contain the internal explosions. Furthermore, during the internal explosion, the internal gases ignite and expand. The enclosure 100 is provided with the flame-paths such as, the first, second, third, fourth, and fifth flame-paths FPI, FP2, FP3, FP4, and FP5. These flame-paths provide passages for the burning gases and/flames to quench and cool down before escaping to the outside of the enclosure 100. While the length and the diametrical gaps for flame-paths referred to in the foregoing disclosure are according to International Standard 60079-1 of ©IEC for mild steel, it will be apparent to one skilled in the art that for an enclosure 100 made of other material such as Aluminum, the length and the diametrical gaps for flame-paths FPI, FP2, FP3, FP4, and FP5 will be according to International Standard 60079-1 of ©IEC for Aluminum.

100321 FIG. 7 is a flowchart for a method 700 of enclosing an electric motor in an enclosure according to an embodiment of the present disclosure. At step 702 of the method 700, the flange plate 144 is attached to the drive end frame 206 of the electric motor 202. In an embodiment, the housing flange of the electric motor 202 is replaced with the flange plate 144. This allows a modified hosing flange of the electric motor 202, such as, the flange plate 144 to correctly align with the ledge member 140 of the enclosure 100 and also receive the adapter nose cone 236 in the shaft opening 150 provided on the flange plate 144, at step 704.

Once, the electric motor 202 is placed within the cavity 104 defined by the enclosure 100, at step 706, the flange plate 144 abuts the ledge member 140 and aligns the first set of the threaded openings 146 provided on the flange plate 144 and the ledge member 140. Finally, at step 708, a first set of threaded fasteners are received and fastened to attach the flange plate 144 with the ledge member 140.

100331 The method 700 further includes defining a plurality of flame-paths, such as, the first, second, third, fourth, and fifth flame-paths FP1, FP2, FP3, FP4, and FP5 to quench and cool down the burning gases and/flames before escaping to the outside of the enclosure 100. In an embodiment, a flameproof cable gland is received within the one or more bossed holes 130 of the cable entry arrangement 128 of the enclosure 100 to define the first flame-path FP 1. Further, the second flame-path FP2 is defined between the sleeve member 238 and the pinion gear 224 disposed within the adapter nose cone 236. Furthermore, the third, fourth, and fifth flame-paths FP3, FF4, and FP5 are defined between the drive end frame 206 and the flange plate 144, and the ledge member 140 and the flange plate 144, respectively. As described above, these flame-paths are designed as per the International Standard 60079-1 of (c1)IEC to suitable for a Zone I application.

100341 The industrial applicability of the enclosure described herein will be readily appreciated from the foregoing discussion. Although the enclosure is shown to house an electric motor, any electrical equipment that may generate sparks due to arcing contacts or generate excessive heat may embody the disclosed systems and methods.

100351 While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of what is disclosed. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.

Claims

Claims What is claimed is: 1. An enclosure for an electric motor comprising: a housing formed from a first plate member defining a cavity therein; a first end and a second end disposed along a longitudinal axis of the cavity; a second plate member attached to the first plate member to seal the cavity at the first end; a edge member attached to the first plate member at the second end; and a flange plate detachably attached to the ledge member, the flange plate is configured to support the electric motor within the cavity, wherein the flange plate and the ledge member define a flame-path.
2. The enclosure of claim 1, wherein the flame-path having a gap based upon at least a length of the flame-path.
3. The enclosure of claim 1, wherein the ledge member and the flange are attached using threaded fasteners.
4. The enclosure of claim 1, wherein the flange plate is provided with a shaft opening, the shaft opening configured to receive an adapter nose cone of the electric motor.
5. The enclosure of claim I further comprising a cable entry arrangement including one or more bossed holes.
6. The enclosure of claim 4, wherein the one or more bossed holes arc configured to receive a flameproof cable gland.
7. The enclosure of claim I further comprising a support member provided between the first end and the second end, the support member having two legs attached to the first plate member.
8. The enclosure of claim 6, wherein the support member includes a gripping portion.
9. The enclosure of claim 1, wherein the first plate member and the second plate member partly divide the cavity into an upper compartment and a lower compartment.
10. A starter motor assembly comprising: an electric motor, the electric motor including: a driven end frame; a drive shaft extending through the driven end frame; an adapter nose cone partly shielding a pinion gear attached at a distal end of the drive shaft; and a sleeve member disposed between the adapter nose cone and the pinion gear; and an enclosure for the electric motor, the enclosure including: a housing formed fixnn a first plate member defining a cavity therein; a first cnd and a second end disposed along a longitudinal axis of the cavity; a second plate member attached to the first plate member to seal the cavity at the first end a ledge member attached to the first plate member at the second end, and a flange plate detachably attached to the ledge member, the flange plate supports the electric motor within the cavity, wherein the flange plate and the ledge member define a flame-path.
11. The starter motor assembly of claim 10, wherein the flame-path having a gap based upon at least a length of the flame-path.
12. The starter motor assembly 10, wherein the ledge member and the flange are attached using threaded fasteners.
13. The starter motor assembly 10, wherein the flange plate is provided with a shaft opening, and wherein the adapter nose cone is received within the shaft opening.
14. The starter motor assembly 10 further comprising a cable entry arrangement including one or more bossed holes configured to receive a flameproof cable gland and defining a threaded flame-path.
15. The starter motor assembly of claim 10, wherein the sleeve member and the pinion gear define a cylindrical flame-path, and wherein the cylindrical flame-path having a diametrical gap based upon at least a length of the second flame-path.
16. The starter motor assembly of claim 10, wherein the drive end frame is rigidly attached with the flange plate using a set of threaded fasteners, the set of threaded fasteners defines a threaded flame-path having a diametrical gap based upon a length of the third flame-path.
17. A method of enclosing an electric motor in an enclosure, the method comprising: attaching a flange plate to a driven end frame of the electric motor; receiving an adapter nose cone of the electric motor through a shaft opening in the flange plate; placing the electric motor within a cavity defined by the enclosure; and attaching the flange plate to a ledge member provided on the enclosure and defining a flame-path when attached to the ledge member.
18. The method of claim 16 further comprises providing a cable entry arrangement on the enclosure, the cable entry arrangement including one or more bossed holes defining a threaded flame-path by receiving a flameproof cable gland.
19. The method of claim 16 further comprises defining a cylindrical flame-path between a sleeve member and a pinion gear disposed within the adaptcr nose conc.
20. The method of claim 16, wherein attaching the flange plate to the ledge member comprises defining a threaded flame-path between the drive end frame and the flange plate.