JPH04112641A - Miniature motor - Google Patents

Abstract

PURPOSE:To obtain a miniature motor in which the rigidity of tubular body can be enhanced easily and reliably by providing projecting arched parts and projecting arched side face parts on the engaging face at one edge side of a stripe metallic board element whereas providing recessed arched parts and curved face parts at the recessed arched part on the engaging face at the other edge side. CONSTITUTION:A tubular body is formed through bending to have an oval cross section and engaging faces 2a3, 2a4 are provided at the opposite edges to be jointed at the time of bending. A plurality of projecting arches 2a5 are provided with same intervals on the engaging face 2a3 while furthermore a plurality of continuously waving curved faces 2a6 are provided whereas a plurality of recessed arches 2a7 are provided on the engaging face 2a4 while furthermore a plurality of recessed curved face parts 2a8 are also provided continuously while waving. The projecting arches 2a5 are fitted to the recessed arches 2a7 whereas the projecting curved faces 2a6 are fitted to the recessed curved faces 2a8.

Description

[Detailed description of the invention] [Purpose of the invention]

(Industrial Application Field) The present invention relates to a small motor used to automatically operate a seat in, for example, an electric seat device. (Prior Art) Conventionally, as the above-mentioned small-sized motor, there have been those shown in FIGS. 11 and 12, for example. That is, the illustrated small motor 100 has a cylindrical body 101
In FIG. 11, an end cap 102 is assembled on the left end side, and the cylindrical body 101 and the end cap 102
Then, the yoke 103 becomes. Moreover, on the right end side in FIG. 11 of the cylindrical body 101,
A front cover 105 is attached, and an armature 106 housed in the yoke 103 is rotatably supported by a bearing 105a provided on the front cover 105 and a bearing 102a provided on the end cap 102. The cylindrical body 101 is made by bending and forming a metal plate cut into a rectangular shape into an oval cross-section.
01a and 101b have engaging surfaces 101c that engage with each other when bent and formed. 101d are provided respectively. Furthermore, the engaging surface 101C of the one side has a convex portion 1.
01e is formed continuously through the convex side linear portion 101f, and the convex portion 1 is formed on the engagement surface 101d on the other side.
The recessed portion 101g that engages with 01e is the fourth straight portion 101h.
It is formed continuously through. Here, when bending and forming the metal plate material into an oval shape, the tube is bent while the convex portion 101e is engaged with the concave portion 101g and the convex side straight portion 101f is in contact with the concave side straight portion 101h. By pressing the cylindrical body 101 from opposing directions along the cylindrical axis direction of the cylindrical body 101, the convex portion 101e is brought into close contact with the concave portion 101g, thereby increasing the rigidity of the cylindrical body 101. (Problem to be Solved by the Invention) However, in the above-described small motor 100, when the convex portion 101e formed on the engaging surface 101C is engaged with the recessed portion 101g formed on the engaging surface 101d, the engaging surface 101C
Since the convex-side linear portion 101f is in contact with the concave-side straight portion 101h of the engagement surface 101d, when trying to increase the rigidity by bringing the convex portion 101e into close contact with the concave portion 101g, the The cylindrical axis direction of the cylindrical body 101 with respect to each straight portion 101f and 101h, that is, each straight portion 101f.
, 101h, it is difficult to say that the linear portions 101f, 101h do not deform toward the separating side. This is because areas with poor adhesion can form. There is a problem in that the durability of the small motor 100 may be significantly reduced due to decreased rigidity, and it has been an issue to solve this problem. (Object of the Invention) The present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to provide a small motor that can easily and reliably increase the rigidity of a cylindrical body.

[Structure of the invention]

(Means for Solving the Problems) A small motor according to the present invention is formed into a substantially cylindrical shape by providing engaging surfaces that can engage with each other on opposite edges of a metal plate material cut into a rectangular shape. In a small motor in which an armature is housed in a yoke that includes a bent cylindrical body and an end cap assembled to the cylindrical body, the engagement surface on the one end edge side has a convex arc and a shape corresponding to the convex arc. A convex arc-side curved surface portion continuous only with a curve is provided, and a concave arc and a concave-arc side curved surface portion that fit into the convex arc and the convex arc-side curved surface portion are provided on the engagement surface on the other end edge side. and the convex arc and the convex arc side curved surface are stacked on the concave arc and the concave arc side curved surface by burring in the same direction as the cylinder axis direction of the cylindrical body. The present invention is characterized by the above-mentioned configuration of the small motor and is a means for solving the conventional problems. (Operation of the invention) In the small motor according to the present invention, the convex arc provided on the engagement surface on the one end edge side and the convex arc side curved surface are formed by burring the cylindrical body from the same direction as the cylinder axis direction. Since it is attached to the concave arc provided on the engagement surface on the other end edge side and the concave arc side curved surface portion, an effect is brought about that the engagement surface is engaged without being deformed toward the separation side. (Embodiment) A small motor according to an embodiment of the present invention will be described below with reference to FIGS. 1 to 9. That is, the illustrated small motor 1 has an armature 3 housed in a cylindrical body 2a that constitutes a part of a yoke 2.
A bearing 4 is attached to an end cap 2b constituting another part of the yoke 2, which rotatably supports one end of an armature shaft 3a provided in the armature 3 on one end side of the cylindrical body 2a. Further, a gear casing side opening 2g is provided on the other end side of the cylindrical body 2a, and this gear casing side opening 2g
The yoke attachment portion 5a provided near the right end of the gear casing 5 in FIG. The gear casing 5 rotatably supports an output shaft 5b, and a bearing 7. A bearing 8 is attached, and the armature shaft 3a is rotatably supported by each of the bearings 4, 7.8. Further, a helical gear 5bl is formed on the output shaft 5b, and this helical gear 5bl meshes with a worm 3al formed near the left end in FIG. 1 of the armature shirt 3a. Further, a cable connecting portion 3a2 for connecting a seat drive cable (not shown) is provided near the right end of the armature shirt 3a in FIG. 1. On the other hand, the cylindrical body 2a is bent and formed into a substantially cylindrical shape with an oval cross section, and both end edges 2al and 2a2 that are joined during bending have engaging surfaces 2a3.2 that engage with each other.
A4 is provided. Further, on the engagement surface 2a3 at one end I&Zal side which is the lower side in FIG. 2 of the engagement surfaces 2a3 and 2a4, there is a convex circular arc 2a5 projecting upward in the figure in an arc shape. A plurality of convex arc side curved surface portions 2a6 are provided at equal intervals, and a plurality of convex arc side curved surface portions 2a6 are provided which are continuous in a wavy manner with only curves to these convex arcs 2a5. Of the engagement surfaces 2a3 and 2a4, the engagement surface 2a4 on the other end edge 2a2 side, which is the upper side in FIG. A plurality of concave arc side curved surface portions 2a8 are provided at equal intervals, and a plurality of concave arc side curved surface portions 2a8 are provided which continue in a wavy manner with only curves to these concave arcs 2a7. Furthermore, the convex arc 2a5 is adapted to fit into the concave arc 2a7, and the convex arc side curved surface portion 2a6 is adapted to fit into the concave arc side curved surface portion 2a8. . Further, on the inner circumferential side of the cylindrical body 2a near the right end in FIG. 1, an annular projection is formed toward the center of the cylindrical body 2a, and a cylindrical body side flat surface 2a9 is formed on the right side in FIG. The formed end cap abutting protrusion 2a10 is provided. Furthermore, on the right side of the end cap abutting protrusion 2a10 in FIG. 1, there is provided an end cap support surface 2a12 having a wall portion 2a11 that is slightly thinner than the wall thickness of the cylindrical body 2a. On the right side of the end cap support surface 2a12 in FIG. 1, there is a circular arc portion forming the oval shape of the cylindrical body 2a, and the end cap support surface 2a12 has a rectangular shape and protrudes toward the right in the figure. The tightening pieces 2a13 are provided at positions facing each other via a notch 2a14 provided in a straight line portion forming the oval shape of the cylindrical body 2a. A mounting portion 2b2 for attaching to the cylindrical body 2a side is provided near the left end of the end cap 2b in FIG. A bearing mounting surface 2b3 formed by a one-step drawing process is formed on the right side of the mounting portion 2b2 in FIG. Further, on the right side of the bearing mounting surface 2b3 in FIG. 1, a cylindrical covering part 2b4 is provided to cover the cable connecting part 3a2 of the armature shirt 3a.
A spline 2b5 for holding a seat drive cable (not shown) is formed on the outer peripheral side of the covering portion 2b4. Here, to explain the forming process of the yoke 2 based on FIGS. 4 to 1O, as shown in FIGS. , a convex portion 20a and a concave portion 20b are continuously provided on the left side, and a tongue piece 2aO for attaching the gear casing is provided on the right side, and one end edge Zal on the upper side in FIG.
A convex arc 2a5 and a curved surface portion 2a6 on the convex arc side are provided on the side engagement surface 2a3, and a concave arc 2a7 and a concave arc 2a7 are provided on the engagement surface 2a4 on the other end edge 2a2 side, which is the lower side in FIG. A concave arc side curved surface portion 2a8 is provided. Then, as shown in FIGS. 5 and 9(a), while bending and forming the plate material 20 into a substantially oval shape, the engaging surface 2a3 is
The convex arc 2a5 and the convex arc side curved surface portion 2a6 of the engaging surface 2a4 are connected to the concave arc 2a7 and the concave arc side curved surface portion 2a of the engaging surface 2a4.
8 to form a cylindrical molded body 21. Thereafter, as shown in FIGS. 6 and 9(b), the molded body 2
From the open end 21a side which is the left side in the figure of 1, a stamping jig having a cross-sectional area slightly larger than the opening cross-sectional area of the open end 21a of the molded body 21 and having an approximate shape is shown. The tool 30 is burred along the cylindrical axis direction of the molded body 21. By performing the burring process using the stamping jig 30, the molded body 21 is pressed in the same direction as the cylinder axis, so that the convex arc 2a provided on the engagement surface 2a3 on the one end Zal side
5 and the convex arc-side curved surface portion 2a6 are stacked in a state of biting into the concave arc 2a7 and the concave arc-side curved surface portion 2a8 provided on the engagement surface 2a4 of the other end edge 2a2gg, so that the convex arc 2a5 and the concave arc The arc 2a7, the convex arc-side curved surface 2a6, and the concave arc-side curved surface portion 2a8 are in close contact with each other in the lateral direction along the cylindrical axis direction of the molded body 21. By performing a burring process using a long stamping jig 30, the convex portions 20a become thin-walled at opposing positions of the open ends 21a of the molded body 21, as shown in FIG. 9(b).
End cap tightening piece 2 protruding to the left inside
a13 and the ninth end cap tightening piece 2a13.
An end cap support surface 2a12 having a thin wall portion 2a11 on the right side in FIG.
An end cap abutting protrusion 2a1 that protrudes in an annular shape toward the inner peripheral side of a and has a cylindrical body side flat surface 2a9.
0 is provided to form the cylindrical body 2a. Then, as shown in FIG. 7 and FIG. 9(C), the end cap 2b is inserted into the opening end 21a, and the end gap side flat surface 2bl provided on the attachment part 2b2 of the end cap 2b is The end cap contact projection 2a10 is brought into contact with the cylindrical body side flat surface 2a9. At this time, the attachment portion 2b2 of the end cap 2b is supported by the end cap support surface 2a12, and in this state, the centering of the bearing 4 attached to the end cap 2b is adjusted. After adjusting the centering of the bearing 4, the end cap 2b is assembled to the cylindrical body 2a by crimping the end cap crimping pieces 2a13 against the opposing sides of the mounting @ 2b2 of the end cap 2b, and the yoke is assembled. 2. Here, since the end cap 2p 2b is in contact with the annular cylindrical body side flat surface 2a9 of the end cap abutting protrusion 2a10, it is crimped from the opposite side by the end cap crimping piece 2a13. The end cap 2b can be easily and reliably assembled to the cylindrical body 2a. Therefore, by supplying a predetermined power to the armature 3 of this small motor 1, the armature shaft 3a is rotated, and the output shaft 5b and the cable connecting portion 3a are rotated.
The seat is moved via a seat slide mechanism (not shown) connected to 2. In this embodiment, the engaging surfaces 2a3 and 2a4 are parallel to the central axis of the cylindrical body 2a, but the engaging surfaces 2a3 and 2a4 are inclined with respect to the central axis. You may do so.

【Effect of the invention】

As explained above, since the small motor according to the present invention has the above-described configuration, it is possible to tightly contact the engaging surface without deforming it to the separating side, so that the rigidity of the cylindrical part can be easily reduced. This has the excellent effect of improving durability.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional side view of a small motor according to an embodiment of the present invention, FIG. 2 is a partially cutaway view of the small motor shown in FIG. 1, and FIG. 3 is a side view of the small motor shown in FIG. 1. Right side view of
Figures 4, 5, and 6. 7 is a process diagram explaining the forming process of the yoke of the small motor shown in FIG. 1, FIG. 8 is a plan view of FIG. 4, and FIG.
Figures (a), (b), and (c) are partially enlarged views of the forming process shown in Figures 4 to 7, and Figure 1O is the end cap and cylindrical shape of the small motor shown in Figure 1. FIG. 11 and FIG. 12 are a longitudinal sectional side view and a front view, respectively, of a conventional small motor. DESCRIPTION OF SYMBOLS 1... Small motor, 2... Yoke, 2a... Cylindrical body, 2a1, 2a2... Edge, 2 & 3. 2 & 4... Engagement surface, 2a5... Convex circular arc, 2a6. ... Convex arc side curved surface part, 2a7... Concave arc, 2a8... Concave arc side curved surface part, 2b... End cap, 3... Armature, 20... Metal plate material.

Claims (1)

[Claims] (1) A cylindrical body formed by bending a metal plate material cut into a rectangular shape into a substantially cylindrical shape with engagement surfaces that can be engaged with each other provided on opposite edges thereof, and assembled to the cylindrical body. In a small motor in which an armature is housed in a yoke equipped with an end cap, the engagement surface on the one end edge side is provided with a convex arc and a convex arc side curved surface portion that continues only with a curve to the convex arc; , on the engagement surface on the other edge side,
A concave arc and a curved surface part on the concave arc side that fit into the convex arc and the curved surface part on the convex arc side are provided, and by burring from the same direction as the cylinder axis direction of the cylindrical body, the convex arc and the convex 1. A small motor, characterized in that a shaped circular arc side curved surface portion is crushed into the concave circular arc and the concave circular arc side curved surface portion.