MXPA00006738A - Reciprocating motor with arcuate pole faces - Google Patents

Abstract

A motor for providing reciprocating motion comprises a stator defining an arcuate pole face and a flat pole face and an armature defining a complimentary arcuate pole face and flat pole face, where the armature rotates about a pivot point in order to maintain a fixed air gap between the arcuate pole faces of the stator and the armature and a variable air gap between the flat pole faces of the stator and the armature.

Description

RECIPROCATING ENGINE WITH ARCHED POLISH SURFACES BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to motors of the type having an oscillating or vibratory armature capable of providing a reciprocating movement to a load attached thereto. 2___ Description of the Prior Art Vibrating motors are well known in the art and are widely used in devices that require a reciprocating action, which is the opposite of a "_. . rotating action. Examples of these devices include dry shaving, hair clippers, massage equipment, sanders, carvers, and certain types of pumps. The typical motor of this type comprises a stator assembly which is held in a stationary position with respect to the housing of the device, and an armature assembly, which is attached to the housing of the device and which is allowed to move in a vibrational relationship to the mounting of stator. The load that requires reciprocating movement, for example, the razor of a hair clipper, is therefore typically attached to the motor armature.

The stator and reinforcement assemblies can be formed from a plurality of laminations composed of a material capable of conducting a magnetic flux and which are riveted or formed together. Steel is commonly used for this purpose. The stator is usually formed in j £ Ug or _ £ E¡¡j§, where the ends of the stator legs form magnetic poles having pole surfaces thereon. The stator further comprises one or more coils of insulated wire wound around one or more legs thereof. The introduction of an electrical signal in the spiral of the wire will cause a magnetic flux to be induced in the stator core that is formed by the stack of laminations. The motor armature is formed in a manner complementary to that of the stator, with an equal number of poles, which also has pole surfaces. The stator and the armature are mounted in such a way that the pole surfaces of the armature face towards the stator pole surfaces, separated by an air gap. The armature can be maintained in its rest position by a resilient means, such as a spring, which will maintain the air gap between the pole surfaces of the armature and the stator pole surfaces. As is well known to those skilled in the art, the pole surfaces of the stator and the armature are attracted to each other, closing the air gap, when the core is magnetized by introducing an electric current into the windings. An alternating current (AC) signal will induce a magnetic flux in the stator core and armature and a magnetic field in the air separation. This causes the poles of the armature and the stator to attract each other and the armature to deflect the resilient medium. During each half of the cycle of the AC signal, as the voltage increases, the force of the magnetic field induced in the air separation increases and the extractor and armature are pulled together, compressing the spring. As the voltage decreases, the magnetic field weakens, thereby allowing the spring to return the armature to its rest position. In this way, it can be seen that the armature will vibrate at a speed twice that of the frequency of the AC current signal introduced in the windings. Preferably, the pole surfaces of the stator and the armature never touch each other. A problem encountered in the manufacture of the reciprocating engine of the prior art is that several adjustments need to be made to each unit, which increases the manufacturing time and, therefore, the manufacturing cost. Typically, an adjustment will be made to adjust the position of the armature with respect to the stator, and a second adjustment will be made to adjust the tension in the spring. The object of the adjustments will be to keep the armature and the stator out of contact with each other as long as the armature is vibrating and to minimize the noise and vibration generated by the motor. Typically, it will be necessary to make several iterations of adjustments, since when making an adjustment the other adjustment point will be affected. Accordingly, it is desired to provide an improved design for a reciprocating or vibratory motor that will eliminate the need for labor-intensive and time-consuming adjustments necessary with the current design.

SUMMARY OF THE INVENTION A reciprocating engine comprises a stator in the form of § £ U§ composed of a plurality of steel laminations and having a unique spiral of enameled copper wire wound around the middle leg of § U§. An armature, also comprised of a plurality of steel laminations, is also provided. Each of the stator and armature has two pole surfaces, one that is arcuate and the other that is flat. The arcuate pole surfaces of the armature and the stator are placed in close proximity to each other, thereby defining an air separation in the form of an extremely narrow arc of constant width between the armature and the stator. The arc of the air separation is on the circumference of a circle, the center of which is a point around which the armature vibrates in a rotational manner. Since the movement of the stator and the armature on the arcuate pole surface is rotational in nature, as opposed to the type of backward and forward motion, the width of the arcuate air gap does not change as the motor vibrates. In the preferred embodiment of the invention, the armature has a hole through the laminations that accepts a post that acts as the pivot or pivot point for the armature. In another embodiment, the pivot point is outside the pile of laminations that define the frame. The other leg of the stator in the form of $ | U¡ $ ¡define a flat pole surface. A flat pole surface for coupling is defined in the frame. The flat pole surfaces of the stator and the armature define an air gap of the size and type commonly known in the prior art. A resilient means is provided along a load-bearing member attached to the armature in order to maintain the armature in its rest position and to provide the force to vibrate the armature against the magnetic field induced in the air separation by the wire spiral. By providing this new design for a reciprocating motor, where a pole surface of both the armature and the stator is arcuately shaped and fixed with respect to its mating pole surface, the number of adjustments required during the process is reduced manufacturing, only the adjustment of the spring tension, which can now be done in an individual iteration, thus reducing manufacturing costs. Another effect of this design is that the stator and armature are more efficient in conducting the magnetic flux and therefore require less steel in the laminations and fewer spiral windings to perform the same work, also decreasing in this way the cost of materials.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be better understood from the following detailed description of the preferred embodiments of the invention, taken in conjunction with the accompanying drawings, in which like reference numbers refer to like parts, and in the which: Figure 1 is a perspective view of the preferred embodiment of the new engine design.

Figure 2 is a front elevational view of the preferred embodiment of the new engine design; Figure 3 is a bottom view of the preferred embodiment of the new engine design; Figure 4 is a rear elevational view of the preferred embodiment of the new engine design. Figure 5 is a top view of the preferred embodiment of the new engine design. Figure 6 is a drawing of an individual stator and armature lamination of the preferred embodiment of the new engine design. Figure 7 is a perspective view of an individual stator and armature lamination of the preferred embodiment of the new engine design. Figure 8 is a view of a lamination of the preferred embodiment of the new engine design showing the flow of the magnetic flux therethrough. Figure 9 is a perspective view of a typical motor design of the prior art. Figure 10 is a front elevational view of a typical prior art motor design. Figure 11 is a top view of a typical engine design of the prior art. Figure 12 is a perspective view of a second embodiment of the new engine design.

Figure 13 is a drawing of an individual stator and armature lamination of a second embodiment of the new engine design. Figure 14 is a perspective view of an individual stator and armature lamination of a second embodiment of the new engine design. Figure 15 is a view of a lamination of a second embodiment of the new engine design showing the flow of the magnetic flux therethrough.

DESCRIPTION OF THE PREFERRED MODE As shown in Figures 1-3, the primary components of the engine in the present description comprise the stator 10 and the armature 12. Both the stator 10 and the armature 12 comprise a stack of individual laminations, 38 and 40, respectively, which are held together by rivets 18. The stator 10 is fixed to the housing member 30 via the rivets 18. The frame 12 is attached pivotably to the housing member 30 by the pivot 20. The spacing between the stator 10 and the armature 12 is maintained by virtue of the connections to the housing member 30 described above and by the spacing member 48 located on the opposite side of the stator 10 and armature 12 of the housing member 30. The arched pole surface 44 is defined by the stator 10, and the complementary arcuate pole surface 46 is defined by the stator 12. The close proximity of the arcuate pole surface 44 of the stator _0 and the The arcuate pole surface 46 of the armature 12 forms the arcuate air gap 29 (best seen in Figure 6) which, in the preferred embodiment, will be between 0.005 and 0.010 inches wide. The armature 12 is free to rotate about the pivot 20, thereby varying the width of the air gap 28. The pivot 20 is placed in the pivot hole 36, best shown in Figures 6-8, which is defined in FIG. the center of a circle, the circumference of which contains an arc defining the arcuate pole surface 46 of the armature 12. The load-bearing member 26 is connected to the armature 12 by rivet 18 and also serves to engage the armature 12 to the deflection spring 22. The stator 10 and the armature 12 are composed of a series of stacked laminations of the type shown in Figures 6 and 7. In the preferred embodiment, 17 laminations are used for both the stator 10 and the armature 12. , each lamination having a height of approximately 0.025 inches for a total height of stator 10 and armature 12 of approximately 0.425 inches. The spiral 14 is preferably composed of enameled copper wire wound around the plastic spool 16. in the preferred embodiment, approximately 2000 turns of wire are used. The stator 10 passes through the center of the plastic coil 16 such that the spiral 14 is wound around the stator 10, such that a magnetic flux is induced in the stator 10 when it is coupled to an electric current to the spiral 14. Air separation 28 is defined between the pole surfaces of the stator 10 and the armature 12 and in the preferred embodiment varies in width from a minimum of about 0.010 to 0.020 inches and a maximum of about 0.100 to 0.120 inches as the armature 12 vibrates with respect to the stator 10. A typical design of the prior art for a vibrating motor is shown in several views in Figures 9-11. Stator 52 is a three-pole stator, as opposed to the stator of a pole of the current design. In this way, there are three air separations 68, visible in Figure 10. The main difference between the prior art units and current design is that the prior art units have a plurality of variable air separations 68, while that the design described herein has only a variable air gap 28. In the prior art unit, shown in Figures 9-11, the stator 52 is fixed within the housing of the unit. The armature 54 and the connecting member 62 are connected to the housing at the set point 64 and the deflection spring 66 makes contact with the connecting member 62 as shown. The armature 54 vibrates via the bending of the connecting member 62 as the stator 52 and the armature 54 are joined together by the force of a magnetic field with the air separations 68., and is removed back to the rest position via the force exerted by the deflection spring 66. It is noted that the oval shape of the adjustment point 64 allows adjustment of the frame 54 and the attachment member 62 back and forth. front with respect to the stator 52, and the adjusting screw 70 allows adjustment of the width of the air separations 68. The set point 64 and the adjusting screw 70 are eliminated with the current design, since the stator 10 and the armature 12 are fixed in their position with respect to each other and the housing member 30. Previously, the adjustment of the prior art unit during the manufacturing process required iterative adjustments, both the position of the armature 54 with respect to the stator 52 via the set point 64, as the adjustment of the width of the air separations 68 via the adjusting screw 70, and the adjustment of the tension in the deflection spring 66 via an adjusting screw (not shown). The adjustment of the current design during the manufacturing process is therefore a non-iterative, individual step that consumes less time for .- > F < - S adjust that the prior art unit. Further, the vibration of the armature 54 with respect to the stator 52 caused by the connecting member 62 to bend back and forth in response to the attractive force between the armature 54 and the stator 52 and the force exerted by the spring 70. to separate the armature 54 and the stator 52 each half cycle. This bending action will frequently cause the connecting member 62 to crack between the biasing spring 66 and the set point 64. This problem has also been eliminated by the preferred embodiment of the current design since the reinforcement 12 of the new pivot design 20, which eliminates the need for a flexible joint member. The current design is also more efficient than the prior art designs, which produces more output wattage per dollar of manufacturing cost. The new lamination design, best shown in Figures 6 and 7, and a second embodiment shown in Figures 13 and 14, is more efficient in conducting the magnetic flux, as shown in Figures 8 and 15, and therefore it requires less steel mass in the stators 10 and 70 and the reinforcements 12 and 76 and a smaller number of windings in the spirals 14 and 92 of the preferred embodiment and the second embodiment of the new design, respectively. It has been found that current designs will require approximately 20% less steel in the laminations of stators 10 and 70 and the reinforcements 12 and 76 and about 25% less windings of enameled copper wire in the coils 14 and 96 to produce the same power output as the prior art motor. An additional advantage of the current design is that it allows a greater travel of the load 24. It will be appreciated by those skilled in the art that the force exerted between the stator 10 and the armature 12 is inversely proportional to the width of the air separation 28. When more than one air gap is present, the energy must be distributed over all air separations, thereby reducing the maximum effective distance between the stator and the armature, and thus also reducing the maximum travel distance of the load, which is typically coupled directly to the frame. For example, if two air separations are present, as in most prior art designs, the force must be distributed over both separations, effectively having the maximum possible width of the air separation during the operation of the unity. In Figures 12 to 15 a second embodiment of the invention is shown. The complete engine using the design of the second embodiment is best seen in Figure 12. In this embodiment, the armature 70 is much smaller in size, and is attached to the flexible beam 72 by rivet 74, and also serves to maintain together the laminations 80 of the armature 70. The flexible beam 72 is in turn rigidly attached to the stator 76 by the rivets 94. In this embodiment, the pivot point 88 is the external stator 76, and is located along the beam flexible 72, which flexes approximately at the pivot point 88. The laminations 82 of the stator 76 are held together by the rivets 78. The deflection springs 84 are also attached to the flexible beam 72. The arcuate, constant air separation 86 is in the circumference of a circle, the center of which is the pivot point 88. Preferably, as with the preferred embodiment, the air gap, arcuate, constant 84 is between 0.005 and 0.01 inches wide, and is optimally close of 0.008 inches wide. The variable air gap 90 formed in stator 76 and armature 70 of flat pole surfaces varies in width between 0.015 and 0.1 inches as the magnetic field and variable air gap 90 varies. Spiral 92 induces magnetic flux both in the stator 76 as in the armature 70, causing the armature 70 to rotate about the pivot point 88, thereby causing the variable air gap 90 to vary in width. The load is attached to the end 96 of the flexible beam 72. Figures 13 and 14 show a view in ili, - plant and in perspective of a lamination 76 'of individual stator and a lamination 70' of individual reinforcement. Figure 15 shows the magnetic flux through the laminations 70 'and 76' and the second embodiment. Although the preferred embodiment and the second embodiment of the present invention have been described above by way of example only, it will be understood by those skilled in the art that modifications may be made to the described embodiments without departing from the scope of the invention, which it is defined by the appended claims, including all equivalents thereof.

Claims (21)

1. CLAIMS; 1. An engine for providing reciprocating movement, comprising: a support member; a stator having a plurality of pole surfaces, at least one of which is arcuate in shape, the stator is rigidly attached to the support member; an armature having a plurality of pole surfaces, at least one of which is arcuate in shape and complementary to the arcuate pole surface of the stator, the armature is attached to the support member and, thus, defines an arcuate separation of air, of fixed width, between the arcuate pole surface of the stator and the arcuate pole surface of the armature; and at least one air gap, of variable width, defined by a pole surface of the stator and a pole surface of the armature, wherein the armature rotates about a pivot point when a magnetic flux is induced in the stator and the armature, and where the arcuate air gap retains a fixed width as the armature rotates and where the variable air gap varies in width as the armature rotates around the pivot point, the width of the variable air gap is dependent on the strength of the magnetic flux. The engine according to claim 1, wherein the pivot point is defined by a post serving as the pivotal union of the frame to the support member, wherein the post passes through the frame at the center point of the frame. a circle, the circle has a circumference containing an arc that defines the arcuate pole surface of the armature. The engine according to claim 1, wherein the support member is a flexible beam and wherein the pivot point is defined as the point along the flexible beam, where the flexible beam flexes as the armature rotates. 4. The motor according to claim 1, further comprising a deflection means, resilient coupled to the armature. The engine according to claim 4, wherein the resilient deflection member is a spring. The motor according to claim 5, wherein the spring is coupled to the support member. The motor according to claim 6, wherein the spring is compressed as the magnetic flux force increases and the width of the variable air gap decreases, and where the spring forces the variable air gap width increase as the force of the magnetic flux decreases. The motor according to claim 1, wherein the magnetic flux is induced towards the stator and the armature by means of one or more induction coils wound around either the stator or the armature. 9. The motor according to claim 8, wherein one or more induction coils are copper wire coils. 10. The motor according to claim 9, wherein the copper wire spirals are enameled. The motor according to claim 9, wherein one or more coils of copper wire are wrapped around a coil composed of a non-conductive material and wherein the stator passes through the coil in such a way as to induce a flow magnetic in the stator when an electric current is coupled to one or more spirals of copper wire. 12. The motor according to claim 11, wherein the electric current is alternating current. The motor according to claim 1, wherein the stator and the armature comprise a plurality of laminations of a material capable of conducting a magnetic flux, the laminations are arranged in a stacked relation to each other. 14. The engine according to claim 13, wherein the laminations are composed of steel. The motor according to claim 2, wherein the armature vibrates with respect to the stator around the post when a magnetic flux is induced in the stator and the armature. The motor according to claim 3, wherein the armature vibrates with respect to the stator about the pivot point when a magnetic flux is induced in the stator and the armature. 17. The engine according to claim 12, wherein the alternating current is alternated between a high peak voltage and a low peak voltage and wherein the armature is rotated towards the stator by a magnetic field in the air gap, thereby narrowing the air gap, as the alternating current reaches the high peak voltage or the low peak voltage and where the resilient deflection means rotates the armature away from the stator as the alternating current reaches the zero voltage, thereby widening the air gap. 18. The motor according to claim 1, wherein a load is coupled to the armature. 19. The motor according to claim 18, wherein the load is the razor of a hair clipper. The motor according to claim 4, wherein the resilient deflection member comprises two opposed springs coupled to the support member which serve to regulate the width of the variable air gap and to dampen the movement of the armature as the armature vibrates towards back and forward. 21. An engine for providing reciprocating movement, comprising: a stator having a plurality of pole surfaces and; an armature having a plurality of pole surfaces; wherein a fixed-width air gap is defined between a pole surface of the stator and a pole surface of the frame and wherein the frame rotates about a pivot point.