JPH04112637A - Miniature motor - Google Patents

Abstract

PURPOSE:To enhance contact tightness between a yoke and a gear casing by forming a tongue side gear casing contacting face, having same plane for the gear casing contact face contacting with the gear casing at the other side, on the tongue and further making a screw hole for securing the yoke. CONSTITUTION:In a miniature motor 1, an armature is housed in a tubular body 2a constituting a part of a yoke 2 and a bearing for rotatably supporting one end of an armature shaft at one end of the tubular body 2a is fixed to an end cap 2b constituting another part of the yoke 2. A screw hole 2a9 for a screw 6 is made close to the end of a protrusion 2a7 and the screw 6 is screwed into the screw hole 2a9 under a state an annular gear casing contact face 2a3 and a tongue side gear casing contact face 2a8 contact with a yoke contact face 5b formed on a yoke fixing part 5a on a gear casing 5 substantially over the entire periphery. According to the constitution, durability is enhanced and high quality can be maintained for a long term.

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. 1O to 12, for example. That is, the illustrated small motor 100 includes a yoke 102 housing an armature 101, and a gear casing 104 rotatably supporting an output shaft 103. An end cap 102b having a substantially conical shape is fixed to the end cap 102a. Further, the yoke mounting portion 104a provided near the right end of the gear casing 104 in FIG. 1O is assembled into the gear casing side opening 102C provided near the left end of the yoke body 102a in FIG. 10. Here, as shown in FIGS. 11 and 12, the gear casing side opening 102c is provided with a substantially flat opening 0 side gear casing contact surface 102d, and
A screw hole 102 protrudes from the opening-side gear casing contact surface 102d toward the outer periphery and into which a screw 110 is inserted.
A tongue piece 102f with an e is provided. Further, as shown in FIG. 12, the two tongue pieces 102f are formed by bending the yoke body 102a clockwise from the state where they protrude upward in the figure.
2av) (I! The side wall 102a is connected to the side wall 102a through the raised portion 102a2 protruding from the I wall 102al to the right side in the figure.
It is shaped so that it is almost perpendicular to l. As a result, the opening side gear casing contact surface 102d
A tongue-side gear casing contact surface 102g having the same plane f1 continuous with the tongue piece 102f is formed on the tongue piece 102f, and each of these contact surfaces 102d. 102g is in contact with the gear casing 104, and insert the screw 110 into the screw hole 102e to remove the gear casing 10.
The yoke 102 is assembled to the gear casing 104 by screwing it into the gear casing 104. A bearing 1 is provided inside the yoke end 102h provided near the right end in FIG. 10 of the yoke body 102a.
05 is attached, and a bearing 106 and a bearing 107 are disposed approximately in the center of the gear casing 104 and near the end opposite to the yoke attachment portion 104a, and these bearings 105, 106, Armature 1 by 107
An armature shirt (armature shirt) 101a provided in 01 is rotatably supported. Also, the first armature shaft 101a
A worm 101b is formed near the left end in FIG. 0, and this worm 101b meshes with a helical gear 103a formed on the output shaft 103. Furthermore, a cable connection part 101c for connecting a seat drive cable (not shown) is provided near the right end of the armature shaft 101a in FIG. The end cap 102b is fixed by spot welding at welding positions 102bl and 102bl. This end cap 102b is provided with a cylindrical covering part 102b2 that covers the cable connecting part 101c provided on the armature shaft 101a, and the seat driving cable is held on the outer circumferential side of this covering part 102b2. A spline 102b3 is formed for this purpose. Furthermore, the yoke body 102a includes a yoke end 10
2h is formed by a two-stage drawing process, and a bearing mounting surface 102al for mounting the bearing 105 is formed on the inner side near the final stage of the drawing process, that is, near the right end in FIG. Therefore, by supplying a predetermined power to the armature 101, the armature shaft 101a is rotated, and the seat is moved via a seat slide mechanism (not shown) connected to the output shaft 103 and the cable connection portion 101c. (Problem to be Solved by the Invention) However, in the conventional small motor 100 described above, 1
A tongue piece 102f provided on the yoke body 102a extends from the yoke body 102a to the side wall 10 via the raised portion 102a2.
2al, and in order for the tongue piece 102f to form the same plane f1 with the opening side gear casing contact surface 102d, the tongue piece 102f is shaped so as to be approximately perpendicular to the opening side gear casing contact surface 102d. Since the yoke main body 102a is molded, the side wall 102al is deformed to the right side in FIG. If the adhesion of the main body 102a to the gear casing 104 has decreased significantly,
There is a problem in that the airtightness deteriorates, making it easy for dust and the like to enter, thereby reducing durability performance, and it has been a challenge to solve this problem. (Object of the Invention) This invention was made in view of the above-mentioned conventional problems, and provides a small motor with improved durability by ensuring airtightness between the yoke and the gear casing. The purpose is to

[Structure of the invention #t]

(Means for Solving the Problems) A small motor according to the present invention includes a cylindrical body housing an armature, and an end mounted with a bearing rotatably supporting an end portion of the armature on one end side of the cylindrical body. In a small motor including a yoke having a cap and a gear casing assembled to the yoke, the yoke includes an annular gear casing contact surface that abuts the gear casing on the other end side of the cylindrical body and an annular gear casing contact surface. A tongue piece is provided that forms a gear casing contact surface on one side of the tongue having the same plane as the contact surface and has a screw hole into which a yoke fixing screw is inserted, and the base of the tongue piece contacts the gear casing. A cutout groove is provided between the tongue and the gear casing contact surface so that the tongue gear casing contact surface approaches the annular gear casing contact surface. This is a means for solving the conventional problems by using the above-mentioned small motor configuration. (Operation of the Invention) The small motor according to the present invention has a gear casing contact surface on one side of the tongue that has the same plane as the gear casing contact surface that contacts the gear casing on the other end side of the cylindrical body. and has a screw hole into which a yoke fixing screw is inserted, and the gear casing contact surface for the tongue piece is bent in a state close to the gear casing contact surface due to the notched groove. There is no need to provide a raised part on the cylindrical body, and the gear casing contact surface of the cylindrical body contacts the gear casing almost all around, which further improves the adhesion between the yoke and gear casing. . (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, on the other end side of the cylindrical body 2a, a gear casing side opening 2al and a tongue piece 2a2 are provided. Yoke mounting part 5 provided near the right end in
The yoke 2 is assembled to the gear casing 5 by screwing in the screw 6 passed through the tongue piece 2a2 with the parts a assembled together. Here, as shown in FIGS. 4 and 5, the gear casing side opening 2al is provided with a flat annular gear casing contact surface 2a3 having a substantially annular shape, and a fifth
In the figure, the tongue piece 2a2 bent at a substantially right angle from the side wall 2a4 of the cylindrical body 2a is provided. Moreover, the annular gear casing contact surface 2a3 and the tongue piece 2a
2, there are provided notch grooves 25 which are cut out with a slight gap downwardly in FIG. 5 at both side portions of the tongue piece 2a2. Then, the tongue piece 2a2 is attached to the bottom wall 2a6 of the notch groove 2a5.
It is bent to the right in FIG. 5 and protrudes to the side in a state in which it approaches the annular gear casing contact surface 2a3 while protruding upward in FIG. A lingual gear casing abutment surface 2a8 having the same plane as the flat surface f2 of the annular gear casing abutment surface 2a3 is formed on the upper surface of the protrusion 2a7 protruding to the right in the figure. Further, a screw hole 2a9 for inserting the screw 6 is provided near the tip of the protrusion 2a7, and the annular gear casing contact surface 2a3 and the tongue-side gear casing contact surface 2a8 are connected to the gear casing 5. The screw 6 is inserted into the screw hole 2a9 and screwed into the screw hole 2a9 while the screw 6 is in contact with the yoke contact surface 5b formed on the yoke attachment portion 5a provided on the yoke over almost the entire circumference. On the other hand, the gear casing 5 rotatably supports an output shaft 5C, and a bearing 7. A bearing 8 is attached, and the armature shirt 3a is rotatably supported by each of the bearings 4, 7.8. Further, a helical gear 5cl is formed on the output shaft 5C, and this helical gear 5cl meshes with a worm 3al formed near the left end in FIG. 1 of the armature shirt 3a. 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, near the right end of the cylindrical body 2a in FIG. 1, there is an end cap portion that protrudes toward the inner peripheral side of the cylindrical body 2a and has a cylindrical portion side flat surface 2&10 on the right side in FIG. A contact protrusion 2a11 is provided on the right side of the end cap contact protrusion 2a11 in FIG.
An end cap support surface 2a13 having a wall portion 2a12 that is slightly thinner than the wall thickness of the cylindrical body 2a is provided. Further, on the right side of the wall portion 2a12 in FIG.
An end cap crimping piece 2a14 protruding toward the right in the figure is provided. A mounting portion 2b2 for attaching to the cylindrical body 2a is provided near the left end of the end cap 2b in FIG. Yes, the first part of this mounting part 2b2
On the right side in the figure, a bearing mounting surface 2b3 formed by one-step drawing process is formed. 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, the forming process of the yoke 2 will be explained based on FIGS. 6 to 9. As shown in FIG. 6, opposing ends 20a of a metal plate material 20 cut into a rectangular shape, 20
b is provided with a locking surface 20e consisting of a convex circular arc portion 20c and a concave circular arc portion 20d that can be engaged with each other at both ends, and a gear casing side end 20f adjacent to the ends 20a and 20b. A tongue piece 2a2 is provided to protrude to the right in FIG. 6 through a notch 112a5. As shown in FIG. 7, while bending and forming the plate material 20 into a substantially oval shape, each convex arc 20c of the engagement surface 20e is engaged with each concave arc portion 20d to form a cylindrical shape. As the molded body 21, an annular gear casing contact surface 2a3 is provided, and the tongue piece 2a2 is further bent toward the outer circumferential side of the molded body 21 through the notch groove 2a5 to provide a tongue-side gear casing contact surface 2a8. . Thereafter, as shown in FIG. 8, from the open end 21a side of the molded body 21, which is the left side in the figure, a cross-sectional area slightly larger than the opening cross-sectional area of the open end 21a of the molded body 21 is opened. A stamping jig 30 having an approximate shape is burred along the sleeve direction of the molded body 21. By performing the burring process using the stamping jig 30, an end cap crimping piece 2a14 is formed on the open end 21a of the molded body 21, protruding to the left side in FIG.
The end cap crimping piece 2a14 has an end cap support surface 2a13 having a thin wall portion 2a12 on the right side in FIG. An end cap abutting protrusion 2a11 having a flat surface 2a10 is provided to form a cylindrical body 2a. Then, as shown in FIG. 9, the end cap 2b is inserted from the right side of the opening end 21a, and the end cap side flat surface 2b1 provided on the attachment part 2b2 of the end cap 2b is pressed against the end cap abutting protrusion. The cylindrical body is brought into contact with the flat surface 2a10 of the cylindrical body 2a11. At this time, the attachment portion 2b2 of the end cap 2b is supported by the end cap support surface 2a13, and in this state, the centering of the bearing 4 attached to the end cap 2b is adjusted to a predetermined position. . After adjusting the centering of the bearing 4, the end cap 2 is tightened by crimping the end cap crimping piece 2a14 against the mounting portion 2b2 of the end cap 2b.
b is assembled to the cylindrical body 2a to obtain the yoke 2. Therefore, by supplying a predetermined power to the armature 3 of this small motor 1, the armature 3 (armature shirt) 3a) is rotated, and a seat slide mechanism (not shown) is connected to the output shaft 5b and the cable connection part 3a2. Move the sheet through. The annular gear casing contact surface 2a3 and the tongue-side gear casing contact surface 2a8 are connected to the yoke contact surface 5.
Since it is in contact with b over almost the entire circumference, yoke 2
Since the gear casing 5 and the gear casing 5 are in close contact with each other, it is difficult for dust to enter even when the armature 3 rotates.

【Effect of the invention】

As explained above, since the small motor according to the present invention has the above-described configuration, the yoke and the gear casing are in close contact with each other, so that the small motor has good airtightness and watertightness. Since no dust or the like can enter, it has the excellent effect of improving durability and maintaining high quality over a long period of time.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional side view of a small motor according to an embodiment of the present invention, FIG. 2 is a partially cutaway plan view of the small motor shown in FIG. 1, and FIG. right side view,
Figures 4 and 5 are external perspective views and longitudinal side views of the small motor shown in Figure 1, respectively, and Figures 6, 7, 8, and 9 are Figure 1. Figures 10 and 1 are process diagrams explaining the process of forming the yoke of the small motor shown in Figures 10 and 1.
Figures 1 and 12 are vertical side views of conventional small motors, respectively.
FIG. 2 is an external view of the area around the tongue and a longitudinal side view of the area around the tongue. DESCRIPTION OF SYMBOLS 1... Small motor, 2... Yoke, 2a... Cylindrical body, 2a2... Tongue piece, 2a3... Annular gear casing contact surface, 2a5...
Notch groove, 2a8... tongue one side gear casing contact surface, 2a9...
・Screw hole, 2b... End cap 3... Armature, 4... Bearing, 5... Gear casing, 6... Screw (screw for fixing the yoke).

Claims (1)

[Claims] (1) A yoke having a cylindrical body housing an armature, an end cap equipped with a bearing that rotatably supports an end of the armature on one end side of the cylindrical body, and a gear casing assembled to the yoke. In the small motor, the yoke includes an annular gear casing contact surface that contacts the gear casing at the other end of the cylindrical body, and a tongue-side gear that has the same plane as the annular gear casing contact surface. A tongue piece is provided which forms a casing abutment surface and has a screw hole into which a yoke fixing screw is inserted, and between the base of the tongue piece and the gear casing abutment surface, there is a tongue piece that abuts the gear casing on one side. A small motor characterized by having a notched groove whose surface is bent in a state approaching the contact surface of the annular gear casing.