JPH07263B2 - Thunder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a sander suitable for use in grinding work such as woodworking products such as furniture, metal products, stone products and the like.

[Conventional technology]

As a sander of this type, for example, as disclosed in Japanese Utility Model Laid-Open No. 2-39862, a substantially elliptical plane motion is made from a rotary drive means to a pad to which grinding paper is attached via a motion conversion mechanism. It is known that the member to be ground is ground by performing the grinding.

[Problems to be Solved by the Invention]

However, in the above-described conventional general sander, the motion trajectory of the grinding paper is fixed in an almost elliptical shape, and other motion trajectories such as reciprocating linear motion or various motions such as rocking motion are ground. It was impossible to give to paper.

Therefore, the part that can be ground by this sander is naturally limited.For example, when grinding the bottom surface of a narrow groove, the grinding paper part intermittently collides with the side wall and the vibration is transmitted to the operator. The efficiency was reduced and the finish was not good.

Further, for example, when the member to be ground is a piece of wood or the like, it is not possible to grind only along the wood grain, and in this case as well, the finished condition is not good.

An object of the present invention is to provide a sander capable of performing a grinding operation on a wider range of ground parts by providing a structure that allows various movements of the grinding paper.

[Means for Solving the Problems]

For this reason, the present invention provides an eccentric shaft mounted at the tip of a rotary shaft rotated by a rotation drive means, a pad guide arranged to face the eccentric shaft, the pad guide slidably and detachably supported, The pad guide is swingably supported on a plane orthogonal to the axis of the eccentric shaft, and the eccentric shaft can be engaged with and disengaged from the engaging portion of the pad by moving toward or away from the eccentric shaft. Equipped with displacement allowance means
Various types of pads are prepared for the engaging portion, the pad guide can be selected and mounted in a state where the pad guide is separated from the eccentric shaft, and the pad guide can be brought close to the eccentric shaft. By engaging the eccentric shaft with the engagement portion, various movements according to the aspect of the engagement portion can be given to the pad.

[Action]

According to the above configuration, by bringing the pad guide close to the eccentric shaft, the eccentric shaft is engaged with the engaging portion of the pad. Movement is imparted and grinding can take place.

On the other hand, when the pad guide is moved in the direction away from the eccentric shaft, the engagement between the engaging portion of the pad and the eccentric shaft is released, whereby the pad can be removed from the pad guide, and therefore the pad can be replaced. After mounting another pad on the pad guide, the pad guide is brought close to the eccentric shaft to engage the eccentric shaft with the engaging portion of the pad, whereby the replacement of the pad is completed. In this way, the pad can be replaced with one touch without using a special tool. When the rotary shaft is rotated by the rotary drive means, the eccentric shaft moves on the circumference centered on the shaft center of the rotary shaft, and the pad has various modes with respect to its engaging portion. Therefore, by appropriately selecting the mode of the engaging portion and mounting the pad, various movements according to the mode of the engaging portion are given to the pad.

For example, if the engaging portion is a long slot long in the direction orthogonal to the sliding direction of the pad, the movement of the eccentric shaft in the direction orthogonal to the sliding direction is absorbed by the long slot and does not act on the pad. Therefore, the pad makes a linear reciprocating motion along the sliding direction (see FIG. 4 (a)).

If the engaging portion is a long slot long in the sliding direction of the pad, the movement of the eccentric shaft in the same direction is absorbed and does not act on the pad. Movement is added. (See Figure 4 (b)).

Further, if the engaging portion is a circular hole having a predetermined diameter, the movement of the eccentric shaft acts on the entire circumference thereof, so that the pad has an elliptical movement in which the movement in the sliding direction and the movement in the direction orthogonal thereto are combined. Exercise (see Figure 4 (c)).

In this way, the pad guide is swingably supported, and the pad is slidably supported by the pad guide, so that the swing motion of the pad guide and the sliding motion of the pad are combined, or By setting the mode of the engaging portion so that only the parts are taken out, various modes of movement are imparted to the pad. Further, since the pads that move differently can be appropriately selected and can be replaced with one touch, various sanding operations can be performed with one sander at the construction site, and thus the work efficiency is improved.

〔Example〕

Next, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 and 2 show the entire sander S of this example.

In the figure, reference numeral 1 denotes a first case having a substantially cylindrical shape.
The case 1 is internally provided with a rotation driving means (illustrated by the air motor M in this example). This air motor M is
The first case 1 is configured to be rotatable and output by compressed air supplied by an air hose 3 connected to a right end surface of the first case 1 via a joint 3a. This rotation output can be turned on / off by operating a knob 4a of the opening / closing valve 4 provided so as to project on the circumferential side surface of the first case 1. Further, a bevel gear 6 is attached to the tip of the output shaft Ma of the air motor M.

Reference numeral 1e is an exhaust hole for returning the compressed air supplied to the air motor M to the atmosphere.

A rubber grip 7 is provided on the outer peripheral surface of the first case 1.
Is attached over almost the entire surface, and the first case 1 is formed as a grip portion of the sander S so that an operator can easily hold it.

The first case 1 in which the air motor M is installed as described above is joined to the second case 2 on the left end side in the drawing.

The second case 2 has a substantially L-shaped appearance, and the first case 1 is joined to the upper end side of the second case 2 via annular locking members 8 and 9 having a brim edge. This second case 2
The output shaft of the air motor M is provided in the recess 2b formed in
A rotating shaft 10 that is orthogonal to Ma in the axial direction is rotatably installed vertically via bearings 11 and 12.

A bevel gear 14 that meshes with the bevel gear 6 is attached to substantially the center of the rotary shaft 10. This bevel gear 14 has a pin 14a.
Is mounted immovably around the axis of rotation 10 via. The rotational output of the air motor M can be transmitted to the rotary shaft 10 via the bevel gears 6 and 14.

The bearing 11 is fitted on the upper edge of the second case 2, and the bearing 12
Is fitted to the inner peripheral side of an annular lid member 13 having a thread groove formed on the outer circumference, and the lid member 13 is screwed to approximately the center of the recess 2b to support the rotary shaft 10. There is.

An eccentric wheel 16 formed in a substantially cylindrical shape is integrally fastened to the lower end side of the rotary shaft 10 formed as described above in the figure by a screw 10a. The eccentric wheel 16 has a mounting hole 16a into which the lower end of the rotary shaft 10 can be inserted, and the inner circumference 16b is formed eccentric by an eccentric amount e with respect to the mounting hole 16a.

At the center of the inner circumference 16b of the eccentric wheel 16, the bearing 1
An eccentric shaft 18 is rotatably supported via 7. That is, the rotary shaft 10 has a structure in which the eccentric shaft 18 having the eccentric amount e is provided at the tip thereof.

Next, below the second case 2 (below the lid member 13), a recess 15 is formed extending further to the right (first case side) than the recess 2b of the case 2.

At the edge of the recess 15 on the first case 1 side, the rotary shaft 10 is provided.
A support member 19 is provided in parallel with. The support member 19 is formed of an elastic member such as urethane rubber in a columnar shape or a prismatic shape, and the upper edge 15a of the recess 15 is formed.
It is attached so as to be rotatable about its axis.

The pad guide 20 is attached to the lower end of the support member 19 thus formed.

In this pad guide 20, for example, a strip steel plate is bent,
A sliding recess 20a having a substantially C-shaped cross section is formed, and a bottom edge of the sliding recess 20a extends rightward in the drawing to form a support edge 20b. The support edge 20b is screwed to the lower end surface of the support member 19, so that the pad guide 20
Are attached to the support member 19.

The pad guide 20 attached to the support member 19 in this manner extends so as to cross the lower side of the rotary shaft 10 and is in a posture orthogonal to the axis of the rotary shaft 10. It is possible to swing around the axis. The sliding recess 20a of the pad guide 20 has the eccentric shaft 1
8 tips are inserted.

Here, since the support member 19 has elasticity, the tip end side of the pad guide 20 is pushed down in the figure to lower the eccentric shaft 18.
Allowed to pull away from. That is, the support member 19 constitutes a displacement permitting means for the pad guide 20. .

The sliding recess 20a of the pad guide 20 formed as described above
A strip-shaped pad 22 is slidably mounted on the.

The pad 22 is made of a slippery material such as cloth baking material, and a mounting plate 23 to which a grinding paper 24 is mounted is attached to the tip end side (the left end side in the drawing) of the pad 22. The mounting plate 23 is made of, for example, a strip-shaped spring steel plate, and has a cushion pad 25 and a surface fastener on its lower surface as shown in the drawing.
26 are attached in layers, and the grinding paper 24 is removable from the mounting plate 23.

Further, an engaging hole 27 as an engaging portion with which the eccentric shaft 18 is engaged is formed at substantially the center of the pad 22. As shown in FIG. 3, the engagement holes 27 are prepared in various shapes in advance.

In FIG. 3, (a) shows a pad 22a having a long slot 27a formed long in a direction orthogonal to the sliding direction of the pad.
(B) shows a pad 22b in which a long slot 27b elongated in the sliding direction is formed, and (c) shows a pad in which a circular hole 27c having a diameter slightly larger than the tip of the eccentric shaft 18 is formed. 22c
Are shown respectively.

In the pad 22 formed as described above, the eccentric shaft 18 is disengaged from the engagement hole 27 of the pad 22 when the pad guide 20 is pushed down as shown in the figure (shown by a chain line in FIG. 1). It is replaceable in this state, and in this state, the pad 22 is inserted into the sliding recess 20a and returned to the position shown by the solid line in the figure, and is attached by inserting the eccentric shaft 18 into the engagement hole 27. It is something.

Reference numeral 32 is a water supply hose connected to the rear end surface of the first case 1 via a joint 31, and the water supplied from the water supply hose 32 flows into a water supply passage 33 formed in the first case 1. The hose 34 through the open / close valve 30 to the pad guide 20.
Is ejected toward. The water ejected in this way is grinding powder (stone powder), for example, when grinding stone products.
The sander S of the present embodiment is configured to be suitably used for grinding stone materials such as tombstones.

Furthermore, as shown in FIG. 2, the sander S of this embodiment is equipped with an air nozzle 35 capable of blowing compressed air to the ground portion. The air nozzle 35 is connected to a branch pipe 36 via an opening / closing cock 37, and the branch pipe 36 is attached to a position where the compressed air is branched between the opening / closing valve 4 and the joint 3a. With this configuration, the air nozzle 35
The compressed air supplied by the air hose 3 can be blown out independently of the operation of the open / close valve 4, and the grinding powder or water can be blown off to easily confirm the finished surface. Here, in order to further enhance the convenience of the air nozzle 35, the opening / closing cock 37 may be an opening / closing cock having a spring-biased lever, which is often seen in so-called air guns.

The present example is configured as described above, and the function and effect described below are achieved by this configuration.

The output shaft Ma of the motor M is rotated by the compressed air supplied from the air hose 3, and this rotation is transmitted to the rotating shaft 10 via the bevel gears 6 and 14. Due to the rotation of the rotary shaft 10, the eccentric shaft 18 moves (circularly moves) through the eccentric wheel 16 on a circle having a constant radius centered on the shaft center of the rotary shaft 10, and therefore the pad 22 As a result, the grinding paper 24 makes various motions (three types are illustrated in this example) in correspondence with the engagement holes 27a, 27b, 27c of various forms as described below.

The movement of the pads 22 to 22 corresponding to the engagement holes 27a, 27b and 27c will be described below with reference to FIG.

In the figure, O ₁ indicates the center of rotation of the rotary shaft 10, and O ₂ indicates the center of swing of the pad guide 20. Further, e indicates the amount of eccentricity of the eccentric shaft 18 with respect to O ₁ , and P indicates one point of the grinding paper 24 (shown as one point on the tip side).

First, the pad 2 provided with the slot 27a shown in FIG.
If 2a is installed (see Fig. 4 (a)), eccentric shaft
Of the circular motion (radius e) of 18, the movement in the direction of rocking the pad 22a is absorbed by the slot 27a, so the pad guide 20 and thus the pad 22a do not rock, and only the pad 22a has an eccentric amount e. The stroke is 2e, which is twice as long as the above. Therefore, the grinding paper 24 makes a linear reciprocating motion, and its stroke is 2e. (The locus of point P is 2e long
Straight line).

In this case, it is preferably used, for example, when grinding the bottom surface of a narrow groove, or when it is desired to grind only along the grain of a wood product.

Further, the pad 2 provided with the slot 27b shown in FIG.
When 2b is installed (see Fig. 4 (b)), eccentric shaft
Since the movement of 18 in the direction of sliding the pad 22b is absorbed by the long groove hole 27b, the pad 22b does not make a sliding movement but makes only a swinging movement about the point O ₂ . Therefore, the grinding paper 24 makes an oscillating motion, and the locus of the point P becomes an arc shape with the radius between the two points P and O ₂ .

If this pad 22b is attached, for example, it is possible to grind the abutting corner portion.

Further, the pad 22c having the circular hole 27c shown in FIG.
When it is attached (see Fig. 4 (c)), the circular hole 27
Since c always follows the movement of the eccentric shaft 18,
The pad guide 20 makes an oscillating motion about the point O ₂ , and the pad 22c makes a sliding motion (stroke 2e) in the pad guide 20. Therefore, the grinding paper 24 combines the oscillating motion and the sliding motion. This will result in an elliptical movement. (The locus of the point P is an ellipse).

In this case, it is suitable for a wide range of grinding work as in the conventional case.

As described above, various pads 22a, 22 having different hole shapes are provided.
By selecting and mounting b and 22c, it becomes possible to give various movements to the grinding paper 24.

From this, it becomes possible to obtain the movement of the grinding paper 24 suitable for various parts or materials of the member to be ground, so that the use range of the sander S (grindable range)
Expands.

When the pad 22 is replaced, the pad guide 20 may be pushed downward in the direction shown in FIG. 1 (the direction away from the eccentric shaft 18) (shown by the alternate long and short dash line in the figure). In this state, the pad 22 is removed from the pad guide 20. Detachable, fit the pad to be used next into the sliding recess 20a of the pad guide 20, and return the pad guide 20 to the solid line position in the figure,
The pad mounting is completed by inserting the tip of the eccentric shaft 18 into the pad engagement hole 27.

In this way, in the sander S of this example, the pad 22 can be easily replaced.

Further, the movement of the grinding paper 24 is such that the movement in the front-back direction (the left-right direction in the drawing) slides within the pad guide 20, and the movement in the swinging direction swings around the support member 19 of the pad guide 20 as a fulcrum. The rotation output of the motor M is efficiently converted into the movement of the grinding paper 24 because the two kinds of movements are given independently of each other or obtained by being combined. The output of the motor M is not consumed for deforming the elastic member that supports the pad. Therefore, there is an effect that the sander S having a larger grinding force can be obtained.

The elastic member (support member 19) as the displacement permitting means of the pad guide 20 is not limited to the illustrated urethane rubber, and may be a coil spring or the like (not shown), and the displacement permitting means is limited to the elastic member. However, the configuration may be as shown in FIG. 5, for example.

That is, a substantially cylindrical support member 40 is rotatably provided with respect to the upper edge 15a of the recess 15 of the second case 2.
A support rod 41 erected on the support edge 20b of the pad base 20 is fitted on the inner periphery of the support base 40, and a position holding means 42 such as a push screw provided at a predetermined position on the circumferential surface of the support member 40 is used. The pad guide 20 may be supported. According to this configuration, the position holding means 42 is released and the pad guide
By moving 20 downward, the engagement between the engagement hole 27 of the pad 22 and the eccentric shaft 18 can be released.

Further, the engagement holes formed in the pad 22 are not limited to the three forms illustrated, but it is possible to cause the grinding paper 24 to move in another mode by reducing the distance in the longitudinal direction of the slotted hole, for example. Further, the engagement hole 27 may be a groove shape that does not penetrate the pad 22, and the point is that the eccentric shaft can be engaged and disengaged and can follow a part or all of the movement (displacement) of the eccentric shaft. Any shape will do.

〔The invention's effect〕

According to the present invention, pads provided with engaging portions of various modes are prepared, and the pads can be appropriately selected and easily attached to the pad guide. Therefore, the pads can be replaced not only by one touch but also by one unit. With the sander main body, various kinds of movements can be given to the pad to rapidly perform various kinds of grinding, and further various kinds of grinding work can be efficiently performed.

[Brief description of drawings]

1 to 3 relate to an embodiment of the present invention,
The figure is a vertical sectional view of the entire sander, and Fig. 2 is a bottom view of the same.
FIG. 3 is an overall perspective view of a pad of various modes, FIG. 4 is an operation explanatory view of the pad, and FIG. 5 is a partial side view showing another embodiment of the displacement permitting means of the pad guide. S ... Thunder M ... Motor, Ma ... Output shaft 1 ... First case, 2 ... Second case 10 ... Rotary shaft, 16 ... Eccentric wheel 18 ... Eccentric shaft, 19 ... Support member 20 ...... Pad guide, 22 ...... Pad 24 ...... Grinding paper 27 (27a, 27b, 27c) …… Engagement hole

Claims (1)

[Claims] 1. An eccentric shaft mounted on the tip of a rotary shaft rotated by a rotary drive means, a pad guide arranged to face the eccentric shaft, the pad guide slidably and detachably supported, and the pad. The guide is swingably supported on a plane orthogonal to the axis of the eccentric shaft, and the eccentric shaft can be engaged with and disengaged from the engaging portion of the pad by moving toward or away from the eccentric shaft. Displacement allowance means is provided, and the pad is provided in various forms with respect to the engaging portion, and the pad guide can be mounted by selecting variously in a state where the pad guide is separated from the eccentric shaft, and the pad guide. By moving the eccentric shaft toward the eccentric shaft and engaging the eccentric shaft with the engaging portion, it is possible to give various movements to the pad according to the mode of the engaging portion. To Nda.