JPH09225805A - Sander - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable the positioning of rotation position of a housing with a good operation characteristic. SOLUTION: A skirt 6 of random orbit sander is mounted so as to rotate freely by assembling an upper opening edge 16 onto a narrow part 15 of a housing. Leaf springs 18, 18 are held and fixed to the connection part of half divisional form of the part 15, respectively. The spring 18 is bent in U shape and has an end thereof on the side of the center of housing formed in the form of a fixed piece 18b while an opposite end thereof formed in the form of elastic piece 18a bent to the side of opening edge 16 with its tip being formed semicircularly, and semicircular notched parts 19, 19 with which the elastic piece 18a is engageable are formed at the equal interval of 30 degrees on the side of opening edge 16 of the skirt 6 being opposite thereto.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention causes a pad mounted on a lower part to perform a predetermined motion (orbital motion) in accordance with the rotation of a motor, and an abrasive material such as sanding paper mounted on the pad is used to remove a workpiece. Regarding sander to be polished.

[0002]

2. Description of the Prior Art FIG. 4 shows a random orbit sander 30 described in US Pat. No. 5,384,984.
A fan 34 is integrally fixed to a rotary shaft 33 of a motor built in the main body housing 31, and a ball bearing 35 is eccentrically provided on the rotary shaft 33 in the fan 34.
Further, a bearing box 36 is attached eccentrically to the ball bearing 35. A pad 37 having sanding paper 38 and the like mounted on the lower surface is screwed to the bearing box 36, and when the motor is rotated, the pad 37 is randomly orbited due to the eccentricity between the ball bearing 35 and the bearing box 36. (Orbital + rotational movement) is performed, and the work piece can be polished. On the other hand, the main body housing 31 includes a skirt 3 as a lower housing that covers the upper portion of the pad 37.
When the skirt 32 is attached to the main body housing 31, the skirt 32 and the main body housing 31 can be relatively rotated by interposing an O-ring 39 and giving a certain amount of crushing. In addition, the frictional resistance with the O-ring 39 enables the body housing 31 or the skirt 32 to be positioned at an arbitrary position, and a dust nozzle (not shown) provided on the skirt 32 or a dust bag attached thereto is obstructive. In such a case, one of the housings can be appropriately rotated to adjust the position.

[0003]

In the connection structure using the O-ring, if the frictional resistance obtained by the O-ring is not appropriate, the rotating operation becomes too loose or too tight.
High dimensional accuracy is required for the main body housing and the lower housing. In addition, since the O-ring is always used in a compressed state, it lacks durability and rattles, or becomes loose and the skirt cannot be positioned.

[0004]

SUMMARY OF THE INVENTION Therefore, the present invention provides a sander having a connecting structure that has good operability in positioning and rotating the housing and has suitable durability. An elastic member that is biased toward the other side is provided on either one of the connecting portions of the housing and the lower housing, and on the other side, a plurality of recesses that the elastic member can engage with are formed, and the elastic member and the recesses are formed. The engagement of the main housing and the lower housing enables the relative rotational positions to be positioned.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. Figure 1 shows Random Orbit Thunder 1
In the illustration of FIG. 2, a motor 3 is built in a main body housing 2 formed of left and right half-splits, and a motor shaft 4 thereof is supported by a ball bearing 5 and is also divided into left and right half-splits. A fan 7 is fixed to the tip of the skirt 6 by a bolt 8 and a washer 9 so that the fan 7 is attached to the lower part of the skirt 6. A bearing box 11 is further eccentrically mounted on the fan 7 through a ball bearing 10 provided eccentrically to the shaft center of the motor shaft 4, and a sanding paper 13 is attached to the lower surface of the bearing box 11. Possible pads 12 are screwed on. Therefore, when the motor 3 is rotated, the rotation is transmitted to the bearing box 11 which is further eccentric through the ball bearing 10 which is eccentric to the motor shaft 4, so that the pad 12 makes a random orbit motion (orbital + rotation motion). become. 20 is a skirt 6
A dust bag 21 that is mounted on the dust nozzle 20, and dust generated during polishing is transmitted through holes provided in the sanding paper 13 and the pad 12 by the fan 7 that rotates integrally with the motor shaft 4. It is sucked into the skirt 6 through 22 and discharged from the dust nozzle 20 to collect dust in the dust bag 21.

As shown in FIG. 2, in the connecting portion between the main body housing 2 and the skirt 6, first, at the lower portion of the main body housing 2, a flange portion 14 for holding the ball bearing 5 and an upper portion of the flange portion 14 are held. And a constricted portion 15 located at
The half skirt 6 is assembled from the left and right and the half halves are screwed together, so that the opening edge 16 of the upper part of the skirt 6 forms a fitting hole having a gap 17 with the outer periphery of the constricted portion 15, and the main body housing 2 will be rotatably gripped. Leaf springs 18, 18, which are elastic members, are sandwiched and fixed to the left and right joints of the constricted portion 15, respectively. This leaf spring 18 is shown in FIG.
As shown in FIG. 1, the mounting groove 1 is formed by bending the end portion of the main body housing 2 on the center side to the inner surface side of the constricted portion 15.
To the fixed piece 18b inserted in 5a, the opposite end,
The elastic piece 1 in which the tip is bent in a semicircular shape by being bent toward the opening edge 16 side of the skirt 6 in the gap 17 and brought into contact with the opening edge 16
8a, each of which has a semicircular notch 19, 19 ... Engageable with the elastic piece 18a at the opening edge 16 side of the corresponding skirt 6 at 30 ° intervals. There is. Here, both leaf springs 18 and 1 are
The eight elastic pieces 18a, 18a are set so that they are engaged with and disengaged from the notches 19, 19 at the same time.

The random orbit sander 1 configured as described above is provided with the elastic pieces 18 of the leaf springs 18, 18.
When a and 18a are engaged with any of the notches 19 of the opening edge 16 of the skirt 6, the elasticity of the a and 18a lock the rotation of the skirt 6. From this state, for example, when the skirt 6 is rotated to the left or right while the main body housing 2 is gripped and fixed, the elastic piece 18a as shown in FIG.
Respectively bend in the gap 17 toward the constricted portion 15 and the cutout portion 19
Since the skirt 6 is disengaged from the skirt 6, the skirt 6 is unlocked by the elastic piece 18a and can be freely rotated to any position. At this time, the elastic pieces 18a separated from the notches 19 give appropriate resistance due to contact with the opening edge 16 while performing a click action, respectively, so that the skirt 6 does not rattle. When the rotation is stopped at an arbitrary position, the elastic pieces 18a,
At the same time, 18a locks the notch 19 at that position to lock the rotation of the skirt 6. Therefore, when the position of the dust nozzle 20 or the dust bag 21 is obstructed by the work, the skirt 6 is rotated to rotate the dust nozzle 20 every 30 ° by 360 ° as shown by the chain double-dashed line in FIG. You can easily change the orientation. Of course, this action can be similarly obtained when the main body housing 2 is rotated while the skirt 6 side is gripped and fixed. As described above, according to the present embodiment, the skirt 6 is positioned by engaging and disengaging the leaf springs 18.
If only the bending amount of the elastic piece 18a of the leaf spring 18 is appropriately set, the positioning function can be easily obtained without being affected by the dimensional accuracy of the main body housing 2 and the skirt 6. Further, since the frictional resistance due to the O-ring is not used, suitable durability can be maintained.

Although the leaf springs 18 are provided at two locations on the main body housing 2 side, they may be provided at one location or at three locations or more, and similarly, the number of notches 19 on the skirt 6 side can be appropriately increased or decreased. In the above embodiment, the leaf spring 18 is provided on the main body housing 2 side and the cutout portion 19 is provided on the skirt 6 side. However, they may be provided in reverse. Further, the shape and the amount of bending of the elastic piece 18a are determined by the load required to rotate the main body housing 2 or the skirt 6 (the load required to separate the elastic piece 18a from the cutout 19).
The design can be changed appropriately according to the setting of, and in addition, the main body housing 2 and the skirt 6 are not rotatable.
By changing the shape of the elastic piece 18a or the shape of the cutout portion 19, the structure may be such that the elastic piece 18a can rotate only in one direction.
Other elastic members may be composed of a plurality of parts such as balls urged by coil springs or leaf springs instead of the leaf springs, and the tool to be applied may be a pad other than the random orbit sander. Can also be used in other types of sanders, such as orbital sanders that perform a single orbital motion.

[0009]

As described above, according to the present invention, the engagement of the elastic member provided on one of the main body housing and the lower housing with the recess provided on the other housing allows the housing to rotate without being affected by the dimensional accuracy of the housing. Positioning can be easily performed with good operability, and durability can be maintained appropriately.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a random orbit sander.

FIG. 2 is an explanatory view of a connecting portion between a main body housing and a skirt.

FIG. 3A is an explanatory diagram of a leaf spring. (B) It is explanatory drawing of a leaf spring.

FIG. 4 is an explanatory diagram of a conventional random orbit sander.

[Explanation of symbols]

1 ・ ・ Random orbit sander 2 ・ ・ Main body housing 3 ・ ・ Motor, 6 ・ ・ Skirt, 10 ・ ・ Ball bearing, 11 ・ ・ Bearing box, 12 ・ ・ Pad, 14 ・ ・ Flange part, 15 ・ ・ Constriction Department, 16 ...
Opening edge, 18 ... Leaf spring, 19 ... notch.

Claims (1)

[Claims] 1. An upper body housing having a built-in motor, and a lower housing provided with a pad to which a predetermined motion is given by the rotation of the motor and rotatably connected to a lower portion of the main body housing. A sander in which a dust discharge pipe is projectingly provided on the lower housing, wherein one of the connecting portions of the main body housing and the lower housing is provided with an elastic member urged to the other side, and the other is provided with the elastic member. A sander characterized in that a plurality of recesses that can be engaged with the member are formed, and the relative rotation position of the main body housing and the lower housing can be positioned by engaging the elastic member with the recesses.