JP2000254852A - Clamping device for sander - Google Patents

Abstract

PROBLEM TO BE SOLVED: To firmly fix a polishing sheet. SOLUTION: This device is provided with an oscillation plate 7 on the under surface of which a polishing sheet is applied and on the upper surface of which the folded-back two ends of the polishing sheet are applied. A holder 8 to press the folded-back two ends of the polishing sheet against the upper surface of the oscillating plate 7 is mounted on the oscillating plate 7. The press part 8a of a holder 8 is brought into surface contact with the polishing sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for clamping a polishing sheet in a sander.

[0002]

2. Description of the Related Art In an orbital sander, a polishing sheet such as sandpaper is attached to a swinging plate that swings back and forth and left and right in a plane, and a work is polished with the polishing sheet while swinging the swinging plate. I have. The polishing sheet is detachable from the swing plate by a clamp device arranged on the swing plate. To attach the polishing sheet to the rocking plate, place the center of the polishing sheet on the lower surface of the rocking plate, fold both ends to the upper surface of the rocking plate, and clamp the folded ends on the rocking plate. Clamp with device.

[0003] An example of a conventional clamping device will be described in more detail with reference to Figs. 10 and 11. In this clamping device, a polishing sheet 1 such as sandpaper is applied to a lower surface and the polishing sheet 1 is folded. And a pair of holders 3 mounted on the oscillating plate 2 for pressing the folded both ends 1a of the polishing sheet 1 against the upper surface of the oscillating plate 2. .

Each holder 3 is formed by bending a wire made of a spring material.
Bracket 4 arranged along the edge corresponding to both ends 1a of the
a, 4a and between the brackets 4b, 4b so as to be rotatable, and a pressing portion 3 for pressing the polishing sheet 1
a is provided between the brackets 4a, 4a and between the brackets 4b, 4b, respectively, and the operation lever 3b is provided outside the brackets 4a, 4b. The pressing portion 3a is formed by bending the wire between the brackets 4a, 4a and between the brackets 4b, 4b so as to project in a convex manner toward the edge of the swing plate 2. Operation lever 3
b is formed so as to extend along another edge crossing the edge of the swinging plate 2 where the pressing portion 3a faces, and is bent outward from the edge when no external force is applied, and the upper surface of the swinging plate 2 It is going down. On the other hand, a locking portion 5 for locking the elastically deformed operation lever portion 2b when the operation lever portion 2b is elastically deformed to the upper surface of the rocking plate 2 is provided on the upper surface of the rocking plate 2. ing.

Although not shown, the pressing portion 3a of the holder 3 is inclined so that a gap is formed between the swing plate 2 and the operation lever 3b when the holder 3 is released. Since the pressing portion 3a generates a larger pressing force on the operation lever portion side than on the opposite operation lever portion side, by providing such an inclination, the pressing force on the polishing sheet 1 is uniformly distributed over the entire length of the pressing portion 3a. I am trying to do.

In order to mount the polishing sheet 1 on the swinging plate 2 by this clamping device, both operation levers 3
b is released from the locking portion 5 to be released, and one end 1 a of the polishing sheet 1 folded on the swinging plate 2 is inserted under the pressing portion 3 a of one holder 3. Therefore, when the operating lever 3b is pushed upward above the swing plate 2, the pressing portion 3a rotates downward with the bracket 4 as a fulcrum, and pushes one end 1a of the polishing sheet 1 onto the swing plate 2. When the operating lever portion 3b is elastically deformed as it is on the swing plate 2 in the horizontal direction and is locked on the locking portion 5, the pressing portion 3a presses one end 1a of the polishing sheet 1 onto the swing plate 2. Maintain state. By operating the other holder 3 in the same manner as described above, the other end 1a of the polishing sheet 1 is fixed on the swing plate 2. Thus, the attachment of the polishing sheet 1 to the swing plate 2 is completed.

[0007]

The above-mentioned conventional clamping device has the following problems. Since it is difficult to adjust the inclination of the pressing portion 3a of the holder 3 and the load distribution becomes uneven, the polishing sheet 1 tends to shift during the polishing operation, and the polishing operation must be frequently interrupted. As shown in FIG. 11, since the pressing portion 3a is in line contact with the polishing sheet 1, the frictional force generated between the pressing portion 3a and the pressing portion 3a is small. In the above case, it is conceivable to increase the holding force by increasing the strength of the holder 3, but in this case, there is a problem that the swinging plate 2 bends and the polishing becomes uneven.

[0008]

In order to solve the above-mentioned problems, the invention according to claim 1 is directed to a polishing sheet (6) applied to a lower surface of the polishing sheet (6) with both ends (6) folded back.
a) the swinging plate (7) having the upper surface applied to the upper surface, and the swinging plate (7) pressing the folded both ends (6a) of the polishing sheet (6) against the upper surface of the swinging plate (7). And a holder (8) mounted on the sander, the pressing portion (8a) of the holder (8) pressing the polishing sheet (6) comes into surface contact with the polishing sheet (6). Adopt sander clamping device.

According to a second aspect of the present invention, there is provided an oscillating plate (7) in which the polishing sheet (6) is applied to the lower surface and the folded both ends (6a) of the polishing sheet (6) are applied to the upper surface. And a holder (8) mounted on the rocking plate (7) for pressing the folded both ends (6a) of the polishing sheet (6) against the upper surface of the rocking plate (7). In the apparatus, a pressing portion (8) for pressing the polishing sheet (6) of the holder (8).
a) adopts a sander clamping device whose surface has irregularities (13).

The invention according to claim 3 is a swing plate (7) in which the polishing sheet (6) is applied to the lower surface, and the folded both ends (6a) of the polishing sheet (6) are applied to the upper surface. And a holder (8) mounted on the rocking plate (7) for pressing the folded both ends (6a) of the polishing sheet (6) against the upper surface of the rocking plate (7). In the apparatus, a pressing portion (8) for pressing the polishing sheet (6) of the holder (8).
An upright wall (14) is provided on the oscillating plate (7) so as to be adjacent to (a), and the polishing sheet (6) is erected on the oscillating plate (7) by the pressing portion (8a). A sander clamping device pressed against both the wall (14) is employed.

[0011]

Next, embodiments of the present invention will be described with reference to the drawings.

<First Embodiment> A sander is provided with a clamp device as shown in FIGS. 1 to 3 for holding an abrasive sheet such as sandpaper below a housing (not shown).

As shown in FIGS. 1 to 3, the clamping device comprises a swinging plate 7, which has a polishing sheet 6 applied to the lower surface thereof and folded ends 6 a of the polishing sheet 6 applied to the upper surface, And a holder 8 attached to the swing plate 7 for pressing the folded both ends 6a against the upper surface of the swing plate 7.

The swing plate 7 has a base plate 7a connected to an output shaft of an electric motor (not shown) housed in the housing (not shown), and a pad plate 7b fixed with an adhesive or the like below the base plate 7a. An eccentric shaft is attached to the output shaft of the electric motor (not shown), and the eccentric shaft is fitted into the boss 9 on the base plate 7a via a bearing. The four corners of the swing plate 7 are connected to the above-mentioned housing (not shown) by column-like flexible members (not shown) made of rubber or the like. This allows
When the electric motor is driven, the oscillating plate 7 makes an oscillating motion that draws a circle on its plane.

The polishing sheet 6 is applied to the swinging plate 7 such that the central portion thereof is applied to the lower surface of the pad plate 7b, and both ends 6a thereof are folded back to the upper surface of the base plate 7a. The folded back ends 6 a of the polishing sheet 6 are detachably held on the swinging plate 7.

A pair of holders 8 are provided on a base plate 7a so as to correspond to the folded both ends 6a of the polishing sheet 6, respectively. Each holder 8 is formed by bending a wire made of a spring material, and includes a pressing portion 8a for pressing the polishing sheet 6 and an operation lever portion 8b for opening and closing the pressing portion 8a. On the other hand, on the upper surface of the swinging plate 7, both ends 6 a of the polishing sheet 6 which are folded back
Along the edges corresponding to the brackets 10a, 10a, 1
0b, 10b, and a pair of brackets 10a, 1
The pressing portion 8a of the holder 8 is stretched between the pair of brackets 10a and the other pair of brackets 10b.

The pressing portion 8a includes a pair of brackets 10a,
The wire is formed by bending the wire between the pair 10a and the other pair of brackets 10b, 10b so as to protrude toward the edge of the swing plate 7 in a convex manner. As shown in FIG. 4, the pressing portion 8a is brought into surface contact with the polishing sheet 6 by a width A, particularly at both ends. That is, the pressing portion 8a is covered with the elastic member 11 by covering a cylindrical body made of an elastic material such as rubber or wrapping a sheet made of the elastic material around the bent portions at both ends thereof. As shown in FIG. 3, the operating lever 8b is pushed up and the polishing sheet 6 is pushed by the pressing portion 8a.
Is clamped on the upper surface of the oscillating plate 7, the elastic member 1
1 is elastically deformed and comes into surface contact with both ends 6 a of the polishing sheet 6. Thus, the polishing sheet 6 is pressed onto the swing plate 7 by a uniform and large pressing load.

The operating lever portion 8b extends from one end of the pressing portion 8a along another edge of the swinging plate 7 perpendicular to the edge of the rocking plate 7 facing the pressing portion 8a, as shown in FIGS. As shown in the figure, when no external force is applied, the projection protrudes outward from the edge and inclines below the swing plate 7. On the other hand, on the upper surface of the swinging plate 7, an operation lever 8b is provided.
Locking portion 1 for locking the elastically deformed operation lever portion 8b when is elastically deformed to the upper surface of the swinging plate 7.
2 are provided.

Next, the operation of the sander clamping device will be described.

In order to mount the polishing sheet 6 on the swinging plate 7 by this clamp device, both the operating levers 8b are detached from the locking portions 12 to be released as shown in FIGS. First, one end 6a of the polishing sheet 6 folded on the swing plate 7 is pressed into the pressing portion 8 of the one holder 8.
a and the upper surface of the swing plate 7.

When the operation lever 8b is elastically deformed so as to push up to a position above the swing plate 7 with the operation lever 8b, the pressing portion 8a pivots downward with the bracket 10 as a fulcrum. One end 6a of the polishing sheet 6
Is pressed on the swinging plate 7. Further, when the operation lever portion 8b is elastically deformed in the horizontal direction onto the swing plate 7 and is locked to the locking portion 12, the pressing portion 8a presses the one end 6a of the polishing sheet 6 onto the swing plate 7. Maintain state.

An elastic member 11 is attached to the pressing portion 8a. As shown in FIG. 4, the elastic member 11 is elastically deformed and comes into surface contact with the polishing sheet 6, so that the polishing sheet 6
Is firmly pressed onto the swinging plate 7 with a uniform pressing force over the entire width thereof.

By operating the other holder 8 in the same manner as described above, the other end 6a of the polishing sheet 6 can be fixed on the swing plate 7 by the pressing portion 8a. Thus, both ends 6a of the polishing sheet 6 are fixed to the swing plate 7, and the central portion of the polishing sheet 6 contacts the pad plate 7b of the swing plate 7.

Thereafter, the oscillating plate 7 performs an oscillating motion to draw a circle on its plane by the activation of the electric motor.
The work is polished by the polishing sheet 6 below the swing plate 7.

<Embodiment 2> As shown in FIG. 5, a large number of fine irregularities 13 are formed on the surface of the pressing portion 8a of the holder 8 in the clamping device with respect to the polishing sheet 6 (see FIGS. 3 and 4). Have been.

The irregularities 13 are formed by forming minute projections on the surface of the wire itself of the pressing portion 8a by pressing or the like, or by pressing the pressing portion 8a.
It is formed by attaching metal powder, abrasive grains, and the like to the surface of the substrate.

The pressing portion 8 a having the unevenness 13 has a good bite with the polishing sheet 6, and holds the polishing sheet 6 more securely on the swinging plate 7.

<Embodiment 3> As shown in FIGS. 6 to 8, a swing plate 7 in this clamp device is
An upright wall 14 is provided adjacent to the pressing section 8a of the holder 8, and the pressing section 8a presses the polishing sheet 6 against the swing plate 7 and the upright wall 14.

The pressing portion 8a may be formed of only a wire, or may be covered with the elastic member 11 as in the first embodiment.

As shown in FIG. 8, the upper end of the upright wall 14
It may be a curved surface or a square surface.

As a result, the polishing sheet 6 is clamped at two places between the holder 8 and the swinging plate 7 and between the holder 8 and the upright wall 14, so that the abrasive sheet 6 is placed on the swinging plate 7 with a larger frictional force. Is held.

<Embodiment 4> As shown in FIG. 9, a holder 8 on the upper surface of a swing plate 7 in this clamp device is used.
A depression 15 corresponding to the shape of the pressing portion 8a, that is, a groove-shaped depression is formed along the longitudinal direction of the pressing portion 8a at a position where the pressing portion 8a contacts.

Both ends 6a of the polishing sheet 6 are sandwiched between the concave portion 15 and the pressing portion 8a, and the contact area between them is increased, so that the polishing sheet 6 is clamped on the swing plate 7 by a larger frictional force. .

In each of the first to fourth embodiments,
The pressing portion 8a of the holder 8 may be inclined so that a gap is formed between the operating portion 8b and the swing plate 7 when the holder 8 is released. Since the pressing portion 8a tends to generate a larger pressing force on the operation lever portion side than on the opposite operation lever portion side, by providing such an inclination, the pressing force on the polishing sheet 6 is made uniform over the entire length of the pressing portion 8a. And the polishing sheet 6 can be properly held on the swing plate.

In the first, second and fourth embodiments, the upright wall 14 is provided on the swinging plate 7 so as to be adjacent to the pressing portion 8a of the holder 8, and the polishing sheet 6 is rocked by the pressing portion 8a. You may make it press on both the moving plate 7 and the standing wall 14. Thus, the polishing sheet 6 is clamped at two places between the holder 8 and the swinging plate 7 and between the holder 8 and the upright wall 14, and is held on the swinging plate 7 with a larger frictional force.

[0036]

According to the first aspect of the invention, since the pressing portion of the holder against the polishing sheet comes into surface contact with the polishing sheet, the polishing sheet can be held more firmly on the swing plate.

According to the second aspect of the present invention, since the unevenness is formed on the surface of the pressing portion of the holder with respect to the polishing sheet, the gripping of the polishing sheet is good, and the polishing sheet is more securely held on the swinging plate. can do.

According to the third aspect of the present invention, the upright wall is provided on the swing plate so as to be adjacent to the pressing portion of the holder with respect to the polishing sheet, and the pressing portion causes the polishing sheet to move between the swing plate and the upright wall. As a result, the abrasive sheet can be held on the oscillating plate with a larger frictional force by increasing the number of contact portions.

[Brief description of the drawings]

FIG. 1 is a plan view showing a clamp device according to Embodiment 1 of the present invention in an unclamped state.

FIG. 2 is a left side view of the clamp device shown in FIG.

FIG. 3 is a left side view showing the clamp device shown in FIG. 1 in a clamped state.

FIG. 4 is an enlarged view of a main part in FIG.

FIG. 5 is a plan view showing a clamp device according to a second embodiment of the present invention in an unclamped state.

FIG. 6 is a plan view showing a clamp device according to a third embodiment of the present invention in an unclamped state.

FIG. 7 is a left side view showing the clamp device shown in FIG. 6 in a clamped state.

FIG. 8 is an enlarged view of a main part in FIG. 7;

FIG. 9 is an enlarged view showing a main part of a clamp device according to Embodiment 4 of the present invention in a clamped state.

FIG. 10 is a side view showing a conventional clamping device in a clamped state.

11 is a partially enlarged view of the clamp device shown in FIG.

[Explanation of symbols]

 Reference Signs List 6: Polishing sheet 6a: Both ends of the polishing sheet folded back 7: Swing plate 8: Holder 8a: Pressing part 13: Unevenness

Claims (3)

[Claims] 1. An oscillating plate in which a polishing sheet is applied to a lower surface and folded ends of the polishing sheet are applied to an upper surface, and wherein the folded ends of the polishing sheet are pressed against an upper surface of the oscillating plate. A clamping device for a sander including a holder mounted on an oscillating plate,
A sander clamping device, wherein a pressing portion of the holder pressing the polishing sheet comes into surface contact with the polishing sheet. 2. An oscillating plate in which a polishing sheet is applied to a lower surface and folded back ends of the polishing sheet are applied to an upper surface, and wherein the folded both ends of the polishing sheet are pressed against an upper surface of the oscillating plate. A clamping device for a sander including a holder mounted on an oscillating plate,
A pressing device for a sander, wherein a pressing portion of the holder pressing the polishing sheet has irregularities on a surface thereof. 3. An oscillating plate in which a polishing sheet is applied to a lower surface and folded ends of the polishing sheet are applied to an upper surface, and wherein the folded ends of the polishing sheet are pressed against an upper surface of the oscillating plate. A clamping device for a sander including a holder mounted on an oscillating plate,
An upright wall is provided on the oscillating plate so as to be adjacent to a pressing portion of the holder that presses the polishing sheet, and the pressing portion presses the polishing sheet against both the oscillating plate and the upright wall. Sander clamping device characterized by being performed.