JPS6245495Y2 - - Google Patents

Description

[Detailed description of the invention] Technical field This invention relates to a brush holder device for holding brushes in a motor.
In particular, it relates to a device for attaching the lid.

BACKGROUND OF THE INVENTION Normally, a brush of a motor is inserted into a motor case through a hole provided in the motor case, and is held by a cover fitted in the hole so as not to be pulled out from the hole. Since the brush gradually wears out as the motor is used, it is required that the lid be removable in order to replace the brush.

For this reason, in the past, for example,
The configuration shown in the above publication has generally been adopted. In other words, in addition to burring the motor case as a hole for inserting the brush,
A female thread is carved on the inner peripheral surface of the burring hole,
The lid body can be screwed together at its male threaded portion. However, as is well known, it is impossible to perform burring and internal thread cutting in succession, and each must be performed in separate processes.
Moreover, it is necessary to cut the female thread accurately using a jig or the like so that there is no deviation in the thread cutting direction, which is time-consuming and a factor contributing to the high cost of the entire motor. Furthermore, since the lid body is screwed, it is naturally impossible to attach and detach it with a single touch.

In order to solve this problem, a lid mounting device disclosed in Japanese Utility Model Publication No. 11928/1983 was proposed. This device has a hole drilled in the U-shaped curved part of the motor case, a thick groove and a narrow groove connected to the hole, and a protrusion integrally formed on the synthetic resin lid. Yes, to attach the lid to the hole,
The lid is fitted into the hole so that the protrusion passes through the thick groove and is positioned inside the motor case, and then the protrusion is engaged with the narrow groove using the curvature of the motor case. Rotate the lid by a predetermined angle so that the However, with this configuration, when the lid is rotated as described above, the surface of the protrusion may be scraped off by the corner edges of the thick groove and narrow groove, or the inner surface of the motor case may be scraped off. This may cause wear due to sliding contact with the protrusion, resulting in incomplete engagement between the protrusion and the narrow groove. Therefore, when the lid is attached, it rattles or sometimes comes off due to vibrations caused by the rotation of the motor, making it impossible to stably hold the brush.

Purpose of the invention The purpose of this invention was to solve the numerous problems mentioned above, to create a sewing machine brush holder lid that is easy to manufacture, has excellent wear resistance, and that allows the lid to be easily attached and removed with a single touch. An object of the present invention is to provide a body attachment device.

Embodiment Hereinafter, an embodiment embodying this invention will be described based on the drawings. A flat portion 13 is provided at each opposing corner of the motor case 12 of the DC motor 11.
is formed. As shown in FIGS. 2 and 3, each of the planar parts 13 has a circular hole 14 for brush replacement, and a pair of notches extending from the circular hole 14 and located 180 degrees apart from each other. 15 and a pair of locking openings 16 as second locking portions extending from the circular hole 14 and located intermediate between the two notches 15 and having a width narrower than the notch 15 are transparent. It is set up.

As shown in FIG. 2, cylindrical brush holders 18 are fixed to the support plate 17 in the motor case 12 so as to correspond to both the circular holes 14, respectively. A carbon brush 19 is removably inserted into the brush holder 18, and the carbon brush 19 is brought into contact with a commutator 21 of the motor 11 by the spring force of a spring 20 attached to one end of the carbon brush 19. The eyelet-shaped presser body 22 is pressed against the brush holder 1 by the spring force of a spring 26, which will be described later.
8 is held at the outer end opening, whereby the spring 20 is compressed to provide a spring force.

A cover body 23 is removably fitted into each of the circular holes 14, and each cover body 23 is composed of a cap 24 made of synthetic resin and an elastic plate 25 made of metal. As shown in FIG. 3, the cap 24 includes a cylindrical portion 24 that is loosely fitted into the circular hole 14.
a, and a collar portion 24 that engages with the upper surface of the peripheral edge of the circular hole 14.
b, and a guide protrusion 24c that protrudes from the inner bottom surface of the cylindrical portion 24a and is inserted into the center hole 22a of the presser body 22 are integrally formed. The top surface of the cap 24 has a substantially circular recess 24d, and a narrow groove 24e located at the bottom of the recess 24d.
and a pair of grooves 24f spaced apart from each other by 180 degrees from the head to the side.
is formed. A spring 26 having a stronger spring force than the spring 20 is interposed between the inner bottom surface of the cylindrical portion 24a and the presser body 22.

The elastic plate 25 includes a central circular portion 25a that is fitted into the recess 24d so as to form the same plane as the top surface of the head of the cap 24, and a central circular portion 25a that is fitted into the recessed portion 24d.
It consists of a pair of extension parts 25b that are bent from both sides of the groove part 25b and can be fitted into the notch part 15, and the extension parts 25b are bent from both sides of the groove part 24f.
5c, and a clamping portion 25d that is bent from the tip of the fitting portion 25c and positioned with a distance L equal to or more than the wall thickness of the motor case 12 between the flange portion 24b and the flange portion 24b as shown in FIG. It's getting more and more familiar. The central circular portion 25a has an opening 2 facing the narrow groove 24e and having a shape that matches the narrow groove 24e.
5e are transparently provided, and protrusions 25f as first locking portions protrude toward the flange portion 24b side and engage with the locking openings 16, respectively, on both the clamping portions 25d.
is formed.

Now, in order to attach the lid 23 to the circular hole 14 in order to hold the new carbon brush 19, the pair of extensions 25b of the lid 23 are attached to the motor case 12.
The cover body 23 is inserted into the cylindrical part 2 so that it fits through the notch part 15 and is positioned on the inner surface side of the motor case 12.
4a, and if the entire lid body 23 is rotated 90 degrees, the protrusions 25f of both extensions 25b will fit into the notch 15 as shown in FIG.
engaging from below the edge of the locking opening 16 between the
The peripheral edge of the circular hole 14 in the flat portion 13 may be elastically held between the protrusion 25f and the flange 24b of the cap 24. As described above, the lid body 2
3 is fitted into the circular hole 14 at its cylindrical portion 24a and rotated 90 degrees, the lid 23 can be attached to a predetermined position with one touch.

To remove the lid 23, rotate the lid 23 against the elastic clamping force of the protrusion 25f and the flange 24b against the motor case 12 in the reverse order, and pull it out from the circular cutout 14. good.

In this case, the rotation operation of the lid body 23 is performed using the elastic plate 25.
This can be easily done with light force by inserting the tip of a screwdriver into the narrow groove 24e of the cap 24 through the opening 25e.

Furthermore, since the elastic plate 25 that comes into sliding contact with the inner surface of the motor case 12 at the protrusion 25f is made of metal, there is no risk of rattling or the like due to wear.
Although the flange portion 24b also comes into sliding contact with the outer surface of the motor case 12, this portion has a large contact area, so no problem occurs.

Furthermore, this lid mounting device does not require burring or thread cutting, and only one circular hole
4. Since the notch 15 and the locking opening 16 can be punched out at the same time using a press or the like, the machining is extremely simple.

Note that this invention is not limited to the above embodiment, and as shown in FIGS.
f is provided only on one extending portion 25b, and
The number of locking openings 16 may be reduced to one, the narrow groove 24e for the screwdriver and the opening 25e may be shaped like a plus, or the locking openings 16 may be circular and independent as shown in FIG. Contrary to the above embodiment, a locking opening is provided in the clamping portion 25d of the elastic plate 25, and a protrusion that is engaged with the locking opening is provided in the motor case 12, without departing from the spirit of the invention. Can be changed within the range.

Effects of the invention As exemplified in the above embodiments, this invention consists of a lid body made of a synthetic resin cap and a metal elastic body, and between the flange of the cap and the extension of the elastic body. Since the lid body is attached to the motor case by holding the motor case, it is easy to manufacture, has excellent wear resistance, and is extremely easy to attach and remove with one touch. Demonstrate the effect that can be achieved.

[Brief explanation of the drawing]

1 to 4 show an embodiment of a lid mounting device embodying this invention, in which FIG. 1 is a side view of the motor, FIG. 2 is an enlarged sectional view showing the main parts, Figure 3 is an exploded perspective view showing the main parts;
The figure is a cross-sectional view showing the state where the motor case is held in place.
5A to 5C are a plan view of a circular hole portion, a plan view of an elastic plate, and a sectional view of an elastic plate, respectively, showing a modified example, and FIG. 6 is a plan view of a circular hole portion showing another modified example. Motor case 12, circular hole 14, notch 15,
Locking opening 16, lid body 23, cap 24, cylindrical portion 24a, flange portion 24b, narrow groove 24e, groove portion 24
f, elastic plate 25, extension 25b, opening 25e, protrusion 25f, interval L.

Claims (1)

[Claims for Utility Model Registration] 1. A lid 23 that removably fits into a circular hole 14 for brush replacement formed in the motor case 12 and presses a brush holder 18 that supports the brush with its inner surface. In the motor, the lid body 23 is made up of a synthetic resin cap 24 that presses the brush holder 18 and a metal elastic body 25, and the cap 24 has a cylindrical portion 24a that fits into the circular hole 14 and a metal elastic body 25. , a jaw portion 24b that engages with the peripheral portion of the circular hole 14, and a groove portion 24f for fitting the elastic body 25, and the elastic body 25 is fitted into the groove portion 24f of the cap 24. When the jaw 24 is in the
a pair of extending portions 25f located with an interval L equal to or greater than the wall thickness of the motor case 12 between the motor case 12 and the first locking portion 25f formed on at least one of the extending portions 25b The motor case 12 further includes a pair of notches 15 extending from the circular hole 14 into which the pair of extensions 25b can be fitted, and the notches 15.
a first portion on the extending portion 25b located apart from
A second locking portion 25f that can be engaged with the locking portion 25f in an uneven relationship.
A locking portion 6 is formed, and a jaw portion 24b of the cap 24 and an elastic body 25 are formed.
between the motor case 12 and the extending portion 25b of the
A brush holder lid attachment device for a motor, characterized in that the lid 23 is attached to the motor case 12 by clamping the lid 23. 2. The brush holder lid attachment device for a motor according to claim 1, wherein the groove portion 24f of the cap 24 is formed continuously on the head and side portions of the cap 24. 3. The first locking portion on the extending portion 25b is a protrusion 24f formed to protrude toward the jaw portion 24b of the cap 24, and
2. The brush holder lid mounting device for a motor according to claim 1, wherein the second locking portion on the motor case 12 is a locking opening 16 transparently provided in the motor case 12. 4 A thin groove 24e is formed on the upper surface of the head of the cap 24.
is perforated, and the elastic body 25 has its thin grooves 24.
An opening 215e having a shape matching e is drilled,
The brush holder lid attachment device for a motor according to claim 1, wherein the lid 23 is rotated using the narrow groove 24e and the opening 25e.