MXPA99010263A - Bearing clamp for a motor electr - Google Patents

Abstract

The present invention relates to an electronic motor having an axis, said motor comprising: an end frame, said end frame including a hub, said hub including an end surface that lacks any projection and that is substantially perpendicular to the axis, including further said hub an inner surface which is generally transverse to said end surface and which defines a bearing seat; a bearing mounted on said bearing seat, said bearing having an outer surface substantially coplanar with said end surface of said hub; of bearing lock mounted on said end surface of said hub for movement between the locked and unlocked positions, said clip being mounted on said end surface so that, when said clip is in said unlocked position, said clip does not overlap said outer surface of said bearing and said bearing can be installed on, or removed from, said bearing seat, and such that, when said clip is in said locked position, said clip overlaps said outer surface of said bearing to adequately prevent said bearing from being withdrawn from said bearing seat; stator fixed relative to said end frame, an arrow supported by said bearing to rotate about the axis, and a rotor supported by said arrow to rotate therewith in relation to said stator.

Description

BEARING CLAMP FOR AN ELECTRIC MOTOR FIELD OF THE INVENTION The present invention relates, in general, to electric motors that require locking a bearing in an end frame of a motor. Specifically, the present invention relates to a locking clip for an electric motor as such.

BACKGROUND OF THE INVENTION There are several prior art assemblies for locking bearings in an engine end frame, thereby preventing axial movement of a motor shaft. The assemblies previously described for this purpose include fastening a bearing to a housing with a metal plate and bolts, using custom-made bolts, press fit a bearing in a housing and securing the bearings with an adhesive. As can be appreciated, electric motors of the type contemplated for use with the present invention generally require repair from time to time. For example, typically the bearings need to be replaced, the arrows need to be ground or replaced and any number of internal components may need to be fixed or replaced. When disassembling an engine for repair, it is sometimes necessary or desirable to remove a bearing from the end frame of the engine. The bearing locking devices of the prior art present problems with regard to the efficient removal of a bearing from an end frame. In addition to being able to efficiently repair an engine by disassembling a bearing from the end frame, ease of assembly is also of interest. The bearing lock mechanisms of the prior art present several problems in terms of assembly. Using a metal plate to unlock a bearing from an end frame generally requires that the plate be completely unscrewed from the end frame. Since the metal plate is removed from the end frame, parts can be lost or badly accommodated, which prevents the bearing from being reassembled in the end frame of the motor. Attaching a metal plate to an end frame to properly lock a bearing in place requires that the bearing be installed first in the end frame and then the metal plate is placed on the bearing. The plate and bearing should be held in place as the screws tighten the plate to the end frame. Using custom-made bolts generally requires the use of special tools to properly install and remove the bolts, such tools being known to those skilled in the art. If the proper tools are not readily available, installation or removal of a bearing from an end frame may be delayed.

Additionally, when custom-made bolts are used, the bolts must be specially made and the end frame must be properly formed to accommodate the custom-made bolts. To remove a bearing that has been pressed into an end frame, the bearing must be mechanically removed from the end frame or the location where the bearing is supplemented with the end frame must be heated or cooled, depending on the type of material used to remove the bearing. the bearing and the end frame, to properly separate the bearing from the end frame. When a bearing is pressed into an end frame, special machinery and procedures, such as those known to those skilled in the art, should be used. Removing a bearing that has been adhesively bonded to an end frame generally destroys the adhesive. To properly replace or replace the bearing, additional adhesive must be appropriately applied. Securing a bearing with adhesive requires the use of a special adhesive that can withstand the ambience of an electric motor, as is well known to those skilled in the art. The bearing lock devices and methods of the prior art add unnecessary costs, complexity and time to the overall assembly of securing a bearing to an end frame.

Another prior art device that secures a bearing to an end bell of a motor is described in the U.S.A. No. 2,772,929. In the '929 patent, the detents 62 engage the stops 66 that are formed on the inner surfaces of an embossment 52. The embossment 52 must be properly aligned with the outer surface of the bearing 22 so that the detents 62 properly secure the bearing 22 in its place. However, because the stops 66 are formed on the elevation 52, the machining of the enhancement to the appropriate dimension is not possible based on the width of the bearings. Therefore, if the lug 52 does not properly align with the outer surface of the bearing 22 when the bearing 22 is placed within the lug 52, the lug can not be easily machined to the proper size. If the outer surface of the bearing 22 does not properly match the upper surface of the elevation 52, the bearing will not be properly fixed to the end bell, possibly causing in this way problems of operation with the engine.

BRIEF DESCRIPTION OF THE INVENTION What is needed is a bearing lock assembly that is cheap to manufacture but is capable of locking a bearing in place.

What is also needed is a bearing lock assembly that is easy to assemble. What is also needed is a bearing lock assembly that allows efficient assembly, disassembly and repair of the engine. The present invention provides a bearing lock clip for an electric motor. The bearing lock clip is secured to an end frame of the motor and fixes a motor bearing in place in the end frame. The bearing lock clip includes a tongue designed to seat different portions of an outer surface of the end frame or the hub of the end frame at different times. To lock a bearing to an end frame, the frame locking clip is rotated, preferably by tightening the screw securing the clip to the end frame, until the tongue of the clip seats a surface on the end frame. The bearing lock clip is designed in such a way that, in this position, a part of the bearing lock clip is placed on the outer surface of the bearing. The bearing lock clip is tightened further to the end frame while the tongue continues to engage the surface of the end frame. To unlock the bearing from the end frame, the bearing lock clip is rotated in the opposite direction (preferably by loosening the screw) until the tab seats another surface on the end frame. The bearing lock clip is designed so that, in this position, no part of the bearing lock clip covers any part of the bearing. Therefore, the bearing can be removed from or installed in the end frame.

Accordingly, a feature of the invention is to provide a bearing lock clip whose manufacture is inexpensive and which allows a bearing to be locked or unlocked to an end frame of a motor. Another feature of the invention is to provide a bearing lock clip that is easy to use and simplifies the process of attaching a bearing to an end frame. The bearing lock clip can be pre-assembled before a bearing is inserted into an end frame and the bearing lock clip allows a blind assembly. A further feature of the invention is to provide a bearing lock assembly that allows the hub or surface of an end frame to be machined so that a bearing fits properly within the hub or end frame. Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of the end frame of the engine with a bearing lock clip in accordance with the present invention. Figure 2 is an enlarged partial perspective view of an electric motor including the bearing lock clip of Figure 1, showing the relationship between the bearing lock clip, a bearing and the end frame of the engine. Figure 3 is a partial end view of the engine showing the bearing lock clip in an unlocked position. Figure 4 is a partial end view of the engine showing the bearing lock clip in a locked position. Figure 5 is a partial, partially separated, side view of the engine. Before one embodiment of the invention is explained in detail, it should be understood that the invention is not limited in its application to the details of construction and arrangement of the components indicated in the following description or illustrated in the drawings. The invention can have other modalities and can be practiced or performed in different ways. In addition, it should be understood that the phraseology and terminology used in the present invention is for purposes of description and should not be considered as limiting.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES Figure 5 illustrates an electric motor 10 that modalizes the invention. The motor 10 consists of a housing 12 having an axis 14. The motor also comprises an end frame 16 mounted in the housing 12. Although in the illustrated construction the end frame 16 is separated from the housing 12, in an alternative embodiment the housing 12 and end frame 16 could be in one piece. The motor also comprises a stator 18 supported by the housing 12 and fixed relative to the end frame 16. A bearing 20 is supported by the end frame 16. A rotor arrow 22 is supported by the bearing 20 to rotate about the shaft 14. The bearing 20 is secured to the arrow 22 at least in part by the retaining element 24. This is further explained below.

A rotor 26 is supported by the arrow 22 so as to rotate therewith relative to the stator 18. Referring to FIGS. 1 and 2, the end frame 16 of the motor has holes 28 therethrough through the which bolts or screws 30 (shown only in Figure 5), conventionally join the end frame 16 of the engine to the housing 12 of the engine. The end frame 16 has a hub 32. Typically the hub 32 has at least one extension 34 extending therefrom. In the illustrated construction, the hub 32 has two lugs 34. Each lug 34 has a respective hole or opening 36 extending from one side to the other thereof. The hub 32 includes a cylindrical inner surface 38, an outer surface 40, a top or end surface 42, and a shoulder 44 extending inwardly from the inner surface 38 and spaced t from and parallel to the end surface 42. The end surface 42 is substantially planar, without any projection and is substantially perpendicular to the axis 14. The external surface 40 is generally perpendicular or generally transverse to the end surface 42 and surrounds the axis 14. The dimension D 'is defined as the depth from the upper surface or end 42 towards the shoulder 44. The inner surface 38 is also generally perpendicular or generally transverse to the end surface 42 and surrounds the shaft 15. The inner surface 38 includes the shoulder 44 and defines a bearing seat 46. The bearing 20 sits on the seat 46 of the bearing and is thus supported by the end frame 16. The bearing 20 can be a number of different types of bearings but a rolling contact bearing with ball bearings 48 (FIG. 5) it is particularly suitable for electric motors of the type contemplated to be used with the present invention. The bearing 20 includes an inner bearing surface 50, an outer bearing surface 52, an upper or outer surface 54 and a depth D in the direction of the shaft 14. A bearing lock clip 56 is secured to the end surface 42 of the hub 32 as will be described later. The bearing lock clip 56 locks or unlocks the bearing 20 to the end frame 16 of the motor. Referring to Figure 2, the bearing lock clip 56 includes a main portion 58 and a tab portion 60 substantially perpendicular to the main portion 58. The function of the tab 60 will be further explained in relation to the total assembly of the components as will be described later. The main portion 58 has an eccentrically located or displaced hole 62 which is preferably threaded extending from one side to the other thereof. The bearing lock clip 56 can be made from any suitable material. However, preferably, the bearing lock clip 56 is a single piece of aluminum or soft metal, manipulated in the proper manner. Still with reference to Figure 2, the components are assembled as follows. Although the assembly is described in the following order, the total steps in the assembly procedure can be performed in a different order to achieve the final product as shown in Figure 1. The depth D of the bearing 20 is measured. that D is determined, the upper or final surface 42 of the hub 32 is machined, if necessary, so that the depth D 'measured from the shoulder 44 to the upper surface 42 is substantially equal to the depth D. Therefore, When the bearing 20 is placed within the seat 46 of the bearing, the outer surface 54 of the bearing 20 is substantially coplanar with the end surface 42 of the end frame 16 of the motor. The bearing lock clip 56 is placed on the end surface 42 of the hub 32 or the boss 34 so that the tongue 60 is adjacent to the outer surface 40 of the end frame 16 and such that the main portion 58 of the clip 56 is seated on the end surface 42. A screw 64 secures the lock 56 to the end surface 42. The screw 64 has a head 66 and a threaded portion 68. The lock washer 70 is positioned around the portion 68 of the screw 64. The screw 64 slides through the hole 36 from the inside of the end frame 16 with the lock washer 70 between the head 66 of the screw and the end frame 16.

The screw 64 is screwed into the hole 62 of the clip 56. In this way, the bearing lock clip 56 can be secured to the end frame 16 before the bearing 20 is placed inside the end frame 16. The arrow 22 is attached to the bearing 20 before the bearing 20 is mounted on the end frame 16, although the bearing 20 can be attached to the attached frame 16 and then the arrow 22 can be attached to the bearing 20. The way in which the bearing 20 is connected to the arrow 22 is not significant. In the illustrated construction, the arrow 22 has an annular groove 72 towards an end 74 of the arrow 22. The end 74 of the arrow 22 slides through the bearing inner surface 50 the bearing 20 until the annular groove 72 extend beyond the outer surface 54 of the bearing 20. Once the groove 72 is properly positioned, the retaining element 24 snaps into the groove 72 so that the ends 76 of the element 24 expand as it extends. the element 24 is placed on the groove 72 and the ends 76 are snapped back into their original position once the inner surface 78 of the element 24 coincides with the surface of the groove 72. The retaining element 24 prevents movement of the arrow 22 with respect to the bearing 20. It should be noted that the arrow 22 is typically provided with a shoulder (not shown) which seats the inside of the bearing 20 to prevent axial movement in the other direction of the arrow 22 with respect to the bearing 20. To further explain the present invention, reference is made to Figures 3 and 4 in conjunction with Figure 2. The bearing lock clip 56 is mounted on the end surface 52 for movement between a locked position (figures 1 and 4) and an unlocked position (figures 3). Before the bearing 20 is placed within the bearing seat 46, the bearing lock clip 56 is placed in the unlocked position. With the clip 56 in the unlocked position, the clip 56 does not overlap with the bearing seat 46 and the bearing 20 can be placed inside the seat 46 of the bearing. When the clip 56 is in the unlocked position and the bearing 20 is in the seat 46 of the bearing, no part of the bearing lock tab 56 covers or overlaps any part of the outer surface 56 of the bearing 20, so that the Bearing can be removed from seat 46 of the bearing. When the clip is in the unlocked position, the tab 60 seats a portion of the outer surface 40 as shown in Figure 3. Engagement of the clip 56 by the surface 40 prevents the clip 56 from moving beyond of the unlocked position, as further described below. With the bearing lock clip 56 in the locked position, as shown in FIG. 4, a portion of the main portion 58 covers or overlaps a portion of the outer surface 54 of the bearing 20 so as to prevent the bearing 20 is removed from the seat 46 of the bearing. When the clip 56 is in the locked position, the tab 60 seats a portion of the outer surface Different from the portion that is engaged when the clip 56 is in the unlocked position, engagement of the clip 56 by the surface 40 prevents movement of the clip 56 beyond the locked position, as will be described further below. Locking tab 56, because it is connected to the screw 64, will turn naturally with the screw 64 as the screw is loosened.

However, since the tongue 60 engages the surface 40 of the end frame 16 the locking tab 56 will no longer rotate even if the screw 64 is further rotated. To lock the bearing 20 in place (see FIG. 4), the screw 64 is tightened, thereby rotating the clip 56 until the tab 60 seats the surface 40 and the clip is in the locked position. This prevents movement of the clip 56 beyond the locked position. The main portion 58 of the clip 56 now overlaps the outer surface 54 of the bearing 20. To unlock the bearing 20 or when the bearing 20 is installed (see figure 3), the screw 64 is loosened, whereby the locking clip 56 is rotated in the opposite direction until the tongue 60 seats another part of the surface 40 so that movement of the clip 56 beyond the position is prevented. not locked At this time the clip 56 does not overlap the outer surface 54 of the bearing 20. In this position, the locking clip 56 does not prevent the removal or installation of the bearing 20. The foregoing description of the present invention has been presented for purposes of illustration and of description. In addition, the description is not designed to limit the invention to the form described herein. Accordingly, variations and modifications commensurate with the above teachings, in technique or knowledge of the relevant art, are within the scope of the present invention. The embodiments described herein are further designed to explain the best known modes for carrying out the invention and to enable others skilled in the art to use the invention as such, or other embodiments and with the various modifications required by the applications or uses. particular of the present invention. It is intended that the appended claims be considered to include alternative embodiments to the extent permitted by the prior art. Various features of the invention are indicated in the following claims.

Claims (10)

NOVELTY OF THE INVENTION CLAIMS

1. An electric motor having an axis, said motor comprising: an end frame, said end frame including a hub, said hub including an end surface that lacks any projection and that is substantially perpendicular to the axis, said club also including a surface internal that is generally transverse to said end surface and which defines a bearing seat; a bearing mounted on said bearing seat, said bearing having an outer surface substantially coplanar with said end surface of said hub; a bearing lock clip mounted on said end surface of said hub for movement between the locked and unlocked positions, said clip being mounted on said end surface so that, when said clip is in said non-locked position, said clip does not overlapping said outer surface of said bearing and said bearing can be installed in, or removed from, said bearing seat, and so that, when said clip is in said locked position, said clip overlaps said outer surface of said bearing to adequately avoid that said bearing be removed from said bearing seat; a stator fixed relative to said end frame; an arrow supported by said bearing so that it rotates around the axis; and a rotor supported by said arrow so that it rotates with it in relation to said stator.

2. An electric motor according to claim 1, further characterized in that said hub includes also an outer surface that is generally transverse to said end surface and which surrounds the shaft, and wherein said bearing lock clip further includes a main portion that seats said end surface and a tongue portion substantially perpendicular to said main portion, said clip being mounted on said end surface so that said tongue is adjacent said outer surface of said hub, so that, when said clip is in said unlocked position, said tab engages a portion of said outer surface so as to prevent movement of said clip beyond said unlocked position, and such that when said clip is in said locked position, said tab is seated another portion of said outer surface so as to prevent the movement of d icha loop past said locked position.

3. An electric motor according to claim 2, further characterized in that said outer surface is substantially perpendicular to said end surface of said hub.

4. An electric motor according to claim 1, further characterized in that said hub includes also an opening extending from said end surface and that is substantially parallel with said axis, and wherein said clip has from one side to another of it a threaded opening, said clip being mounted on said end surface by a screw extending through said opening in said hub and in said threaded opening of said clip, said clip being moved between said locked and unlocked positions by loosening or tightening said screw.

5. An electric motor according to claim 4, further characterized in that said opening is located eccentrically.

6. An electric motor according to claim 1, further comprising a housing, further characterized in that said end frame is mounted on said housing and wherein said stator is supported by said housing.

7. An electric motor having an axis, said motor comprising: an end frame, said end frame including a hub, said hub including an end surface that is substantially perpendicular to the axis, said club also including an outer surface that is generally transverse to said end surface and which surrounds the shaft, said mass also including an internal surface that is generally transverse to said end surface and which defines a bearing seat; a bearing mounted on said bearing seat, said bearing having an outer surface substantially coplanar with said end surface of said hub; a bearing lock clip mounted on said end surface for movement between the locked and unlocked positions, said clip including a main portion that seats said end surface, and said clip further including a tongue portion substantially perpendicular to said main portion said clip being mounted on said end surface so that said tongue is adjacent said outer surface of said hub, such that, when said clip is in said unlocked position, said tongue seats a portion of said outer surface so that avoid movement of said clip beyond said unlocked position, said main portion of said clip not overlapping said outer surface of said bearing and said bearing can be installed in, or removed from, said bearing seat, and so that, when said clip is in said locked position, said tab as the other portion of said outer surface so as to prevent the movement of said clip beyond said locked position, and said main portion of said clip overlapping said outer surface of said bearing to adequately prevent said bearing from being removed from said bearing seat; a stator fixed relative to said end frame; an arrow supported by said bearing so that it rotates around the axis; and a rotor supported by said arrow so that it rotates with it in relation to said stator.

8. An electric motor according to claim 7, further characterized in that said outer surface is substantially perpendicular to said end surface of said hub.

9. An electric motor according to claim 7, further characterized in that said hub also includes an opening extending from said end surface and that is substantially parallel to said axis, and wherein said main portion has from one side to another therein a threaded opening, said clip being mounted on said end surface by a screw extending through said opening in said hub and in said threaded opening of said clip, said clip being moved between said locked and unlocked positions by loosening or by tightening said screw.

10. An electric motor according to claim 9, further characterized in that said opening is located eccentrically. 11- An electric motor according to claim 7, further comprising a housing, further characterized in that said end frame is mounted on said housing and wherein said stator is supported by said housing. 12. An electric motor that consists of: a housing that has an axis; a stator supported by said housing; an end frame mounted on said housing, said end frame including a hub, said hub including a substantially flat end surface that lacks any projection and that is substantially perpendicular to said axis, said hub further including an outer surface that is generally perpendicular to said hub. end surface and which surrounds said axis, said mass further including an interior surface that is generally perpendicular to said end surface, which surrounds said axis and which defines a bearing seat, and said mass further includes an opening extending from said end surface and which is substantially parallel with said axis; a bearing mounted on said bearing seat, said bearing having an outer surface substantially coplanar with said end surface of said hub; a bearing lock clip mounted on said end surface for movement between the locked and unlocked positionssaid clip including a main portion that seats said end surface and having a eccentrically located threaded opening there from side to side, and said clip further comprising a tongue portion substantially perpendicular to said main portion, said clip being mounted on said end surface by a screw extending through said opening in said mass and towards said threaded opening of said clip, said clip moving between the positions locked and not locked by tightening or loosening said screw, said clip being mounted on said surface end so that said tab is adjacent said outer surface of said hub, so that, when said clip is in said unlocked position, said tab seats a portion of said outer surface so as to prevent the movement of said clip beyond of said unlocked position, said main portion of said clip does not overlap said outer surface of said bearing and said bearing can be installed in, or removed from, said bearing seat, and so that, when said clip is in said locked position, said tab seats another portion of said surface outer so as to prevent the movement of said clip beyond said locked position, and said main portion of said clip overlaps said outer surface of said bearing to adequately prevent said bearing from being removed from said bearing seat; an arrow supported by said bearing so that it rotates around the axis; and a rotor supported by said arrow so that it rotates with it in relation to said stator.