JPH077059Y2 - Jig for circular saw grinding - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a jig for circular saw grinding.

[Conventional technology]

When the cutting edge of a circular saw used for wood processing or mowing is worn, the blade is reground by a grinder. In this case, conventionally, an operator manually holds the surface of the circular saw at a certain angle with respect to the horizontal plane and holds it by one blade to bring it into contact with the grinding wheel of the grinder for grinding.

[Problems to be solved by the device]

However, in the above-mentioned method, since the position and angle of the blade with respect to the grinding wheel are difficult to determine, there are variations in grinding angle and depth, and there is a problem that uniform grinding is difficult to perform.

Then, this invention aims at providing the jig attached to the base of a grinder and holding the attitude | position of a circular saw constant.

[Means for Solving the Problems]

In order to achieve the above object, the present invention provides a mounting base 3 for fixing the grinder in the vicinity of the grinding wheel 2, and a bearing piece 4 on the mounting base 3 for mounting the grinding wheel 2 on the bearing piece 4. A support shaft 6 protruding parallel to the shaft 5 is fixed, and a base portion 8 of a circular saw pedestal 7 is rotatably inserted into a fixed end of the support shaft 6 so that a predetermined reference angle and a quasi-reference angle can be taken. The base 8 is pressed against either one of the bearing piece 4 and a part of the support shaft 6 by a spring 9, and a stopper is provided in the middle of the support shaft 6.
11 is slidably and rotatably inserted, the circular saw holder 12 is slidably and rotatably inserted outside the stopper 11, and the positioning member 13 is provided on the inner surface of the circular saw holder 12 so as to project. A positioning recess 14 into which the positioning member 13 fits when the saw holder 12 takes a quasi-standard angle is formed on the outer end surface of the stopper 11.

In addition, the circular saw cradle 7 inserted into the fixed end side of the support shaft 6 described above.
Instead of pressing the base 8 of the circular saw holder 4 against one of the bearing piece 4 and a part of the support shaft 6, the base 8 of the circular saw pedestal 7 is alternatively set at a reference angle and a quasi-reference angle. It is also possible to provide the bearing piece 4 with a positioning device 15 for engaging the position.

[Action]

On the base 1 of the grinder, the mounting base 3 is fixed at a position where the front edge of the circular saw receiving base 7 is close to the grinding wheel 2. The circular saw 20 to be ground is mounted on the circular saw holder 12. Circular saw cradle 7
By appropriately setting the angle of and the position of the stopper 11, the circular saw 20 is held at a predetermined reference angle, and the grinding surface of the blade 21 is held.
Grinding is performed by applying 22 to the grinding wheel 2.

In the case where the grinding surfaces 23, 24 of the blade 21 of the circular saw 20 appear alternately, when grinding the grinding surface 24 on the back surface side, the angle of the circular saw support 7 and the stopper 11 and the circular saw holding base 12 The circular saw 20 is ground at a predetermined quasi-reference angle by changing the relative distance.

In any of the above cases, the circular saw pedestal 7 holds the base portion 8 at the reference angle and the quasi-reference angle by the frictional force due to the pressing force of the spring 9.

On the other hand, the circular saw cradle 7 inserted into the fixed end side of the support shaft 6 described above.
The base 8 of the circular saw pedestal 7 is pressed against one of the bearing piece 4 and a part of the support shaft 6 and the angle of the circular saw pedestal 7 is held by frictional force. When the positioning device 15 that engages with the predetermined position of the bearing piece 4 as an alternative to the quasi-reference angle is provided, the angle of the circular saw pedestal 7 is alternatively set to one of the angles.

〔Example〕

As shown in FIG. 1, the jig for circular saw grinding of the present invention is used by being attached in front of a grinding wheel 2 on the upper surface of a base 1 of a grinder.

This jig has a mounting base 3. The mounting base 3 is fixed to the front of the grinding wheel 2 by bolts 30, and the fixing position can be adjusted appropriately in the direction perpendicular to the shaft 5 by the long hole 25 (FIG. 2) provided in the base 1. I have to.

A bearing piece 4 is erected on the mounting base 3, and a support shaft 6 parallel to the shaft 5 of the grinding wheel 2 is fixed to the outer surface of the bearing piece 4. As shown in FIG. 2, the support shaft 6 has a step portion 26 at the shaft end, and a small-diameter shaft portion 27 at the tip is inserted from the step portion 26 through the base portion 8 of the circular saw pedestal 7 and the bearing piece 4 It is fixed with a screw 28.

A spring 9 is interposed between the base portion 8 of the circular saw pedestal 7 and the bearing piece 4 to press the base portion 8 against the stepped portion 26 and generate a large frictional force with respect to the rotation of the base portion 8. The circular saw pedestal 7 has a recess 29 on the side facing the wheel 2 and the peripheral edge of the wheel 2 faces the recess 29.

A sleeve-shaped stopper 11 is slidably inserted in the middle of the support shaft 6. The stopper 11 is provided with a fixing screw 31 so that the stopper 11 can be fixed to the support shaft 6 at a predetermined position in the axial direction and a predetermined angle in the rotation direction. A positioning recess 14 is provided on the outer end surface of the stopper 11.

Further, the circular saw holding table 12 is slidably inserted into the outer side of the stopper 11 of the support shaft 6 by a guide pipe 32 inserted therethrough. The circular saw holder 12 has a plurality of screw holes 33 on the upper surface and one tightening member 34 facing the screw holes 33. On the lower surface of the tightening member 34, a small protrusion 36 that fits into the center hole 35 of the circular saw 20 is formed (Fig. 10). Further, a positioning member 13 formed of a screw rod is screwed into the circular saw holding table 12 in parallel with the support shaft 6 from the outer surface thereof and penetrates to the inner surface. The tip of the positioning member 13 has the stopper 11 described above.
Abutting on the outer end face of the, or inserted into a recess 14 in that end face as described below.

On the other hand, the circular saw 20 is, as shown in FIG. 3, a ground surface of each blade 21.
22 (From the viewpoint of the cutting action of a circular saw, this surface is a rake surface with a predetermined rake angle, but since this surface will be re-ground due to wear, it is called a ground surface here) Which are all on the same surface side (hereinafter referred to as the single-sided type) and those in which the grinding surfaces 23 and 24 are alternately present on the front and back sides of each blade as shown in FIG. 4 (hereinafter referred to as the double-sided type). ) There is.

When grinding the single-sided circular saw 20, there is no particular problem because the positional relationship between each grinding surface 22 and the grinding wheel 2 is uniquely determined according to the standard of the circular saw 20. That is, the grinding wheel 2 may be contacted along the rake angle of the grinding surface 22.

However, in the case of the double-sided type, the attitude of the circular saw 20 with respect to the grinding wheel 2 is different between when grinding the grinding surface 23 on the front surface side and when grinding the grinding surface 24 on the back surface side. That is, as shown in FIGS. 5 to 8, when the front side grinding surface 23 is ground (this is the same as the case of the single sided type), the attitude of the circular saw 20 with respect to the wheel 2 is as follows. In plan view (FIG. 5), the center line a of the grinding wheel 2 parallel to the surface of the grinding wheel 2 and the grinding surface
It is defined by the intersection angle α ₁ with the tangent line b at the tip of 23. This angle α ₁ is obtained by an operator standing in the direction of the grinding wheel 2 holding the circular saw 20 and moving the circular saw 20 left and right around the contact point with the grinding wheel 2. It can be changed appropriately.

Further, in a side view (FIG. 6), it is defined by an angle β ₁ formed by the surface of the circular saw 20 with respect to the vertical line c. This angle β ₁
Can be changed as appropriate by moving the circular saw 20 up and down around the contact point with the grinding wheel 2.

The above-mentioned angles α ₁ and β ₁ of the circular saw 20 are the posture of the circular saw 20 when it is in a posture that exactly matches the rake angle of the grinding surface 24, that is, the posture when grinding the grinding surface 23 on the front side. In the device, it is called "reference angle". In this case, α ₁ and β ₁ can be known by previously applying the grinding surface 24 of the circular saw 20 to the peripheral edge of the wheel wheel 2 so as to match the rake angle before grinding.

The "reference angle" is the same in the grinding conditions when the grinding surface 22 of the single-sided circular saw 20 is ground, and thus the definition can be used in that case as well.

On the other hand, when grinding the back side grinding surface 24, the intersection angle α ₁ in plan view is changed to α ₂ (FIG. 7), and the angle β ₁ in side view is changed to β ₂ (FIG. 8). . Α ₂ and β _{2 in} this case
Circular saw 20 to match the rake angle of the back side grinding surface 24 beforehand
This can be known by hitting the edge of the grinding wheel 2. When the circular saw 20 is in such a posture that the angles α ₂ and β ₂ are taken, that is, the posture when the back side grinding surface 24 is ground,
In this invention, it is called "preparation sub-angle".

To mount the circular saw 20 on the jig described above, as shown in FIGS. 9 and 10, the circular saw 20 is placed on the circular saw holder 12 and the small projection 36 of the tightening member 34 is placed in the center hole 35 of the circular saw 20. Together with
The circular saw 20 is fixed by tightening screws in appropriate screw holes 33.
In this state, the circular saw 20 can rotate around the small protrusion 36. Further, the circular saw holder 12 can be rotated around the support shaft 6.

After fixing the circular saw 20 on the circular saw holding table 12 as described above, the holding table 12 is moved in the axial direction, and the grinding surface of the circular saw 20 is fixed.
The 22, 23 and 24 are opposed to the peripheral edge of the wheel & pinion 2.

Now, assuming that the grinding surface 22 of the single-sided circular saw is to be ground,
The grinding surface 22 is once applied to the peripheral edge of the grinding wheel 2 to set the reference angle. After that, the stopper 11 is moved so that the outer end surface thereof is brought into contact with the tip end surface of the positioning member 13 protruding from the inner end surface of the circular saw holder 12, and the fixing screw 31 is tightened at that position to fix the stopper 11.

In this case, the angle of the stopper 11 is determined so that the tip of the positioning member 13 does not fit into the recess 14 formed on the outer end surface of the stopper 11. Next, the pedestal 7 is rotated so that the upper surface of the circular saw pedestal 7 is aligned with the lower surface of the circular saw 20 at the reference angle. The pedestal 7 is held at the set angle by a large frictional force due to the pressing of the spring 9.

When set as described above, the reference angle of the circular saw 20 is stored by the fixed position of the stopper 11 and the inclination angle of the pedestal 7, so that the operator holds the circular saw 20 by hand and supports it together with the holding table 12. Even if it is moved in the axial direction of the shaft 6 or rotated around the support shaft 6, the holding table 12 integral with the circular saw 20 is again applied to the stopper 11, and the surface of the circular saw 20 is set on the receiving table 7. Once placed, it can be returned to its original set position again.

When performing re-grinding, the operator grasps the circular saw 20 so as to be in the above-mentioned set state, sets its posture, and tries to re-grind by appropriately rotating the circular saw 20 around the small protrusion 36. Touch the grinding surface 22 of the blade 21 to the grinding wheel 2 and leave the circular saw 20
Grind while firmly gripping.

In this way, when the re-grinding of one grinding surface 22 is completed, the circular saw 20 is lifted from the receiving table 7, and the supporting table 6 is slightly moved together with the holding table 12 to grind the ground surface 22 that has been ground. Separated from the wheel 2, the circular saw 20 is manually rotated to the next grinding surface 22 and again positioned and ground as described above.

Next, the regrinding of the grinding surfaces 23, 24 of the double-sided circular saw is performed as follows.

First, as a preparatory work, the back grinding surface 24 is applied to the grinding wheel 2 and the circular saw 20 is held at a quasi-reference angle, and the stopper 11
Is moved so that the tip of the positioning member 13 penetrates into the recess 14 and the outer end surface of the stopper 11 is brought into contact with the inner end surface of the holding table 12 (see FIG. 11). In this state, the fixing screw 31 of the stopper 11 is tightened to fix the stopper 11. Next, while the surface grinding surface 23 is applied to the grinding wheel 2 and the circular saw 20 is held at the reference angle, the tip of the positioning member 13 of the holding table 12 is brought into contact with the outer end surface of the stopper 11 and, if necessary, the positioning member. Adjust the protrusion amount of 13. In addition, as in the case described above, the pedestal 7 is rotated and applied to the lower surface of the circular saw 20.

After that, the ground surface 23 is reground.

Next, when regrinding the back surface grinding surface 24, the holding table 12 is rotated to fit the tip of the positioning member 13 into the recess 14. While being held in this state, the pedestal 7 is rotated along the lower surface of the circular saw 20 and fixed in that position by the frictional force of the spring 9. As a result, the quasi-reference angle of the circular saw 20 is stored. Therefore, even if the circular saw 20 is appropriately moved after regrinding one back grinding surface 24, when the next grinding surface 24 is reground, the previously set quasi-reference angle is set again.

In the above description, the circular saw pedestal 7 is held at the reference angle and the quasi-reference angle by the frictional force of the pressing force of the spring 9, but as shown in FIG. 13 and FIG. It may be replaced with the positioning device 15 capable of setting the above angle. This positioning device 15 is provided from the rear surface of the bearing piece 4,
The pin 41 supported by the spring 40 is projected so that the pin 41
Is to be able to go in and out of any one positioning hole 42 formed in the base portion 8 of the circular saw pedestal 7.

An auxiliary base 7'is provided on one side of the circular saw receiving base 7 and a positioning wall 45 is formed on the auxiliary base 7 ', so that the positioning wall 45 is circular as shown by the chain double-dashed line in FIG. The blades of the saw 20 are brought into contact. While the circular saw 20 is positioned by the contact, one edge of the blade is applied to the grinding wheel 2 for grinding.
By sequentially rotating the circular saw 20 one by one, the peak of each blade can be ground.

[Effect of device]

As described above, according to the present invention, when the circular saw is ground, the posture can be positioned so as to maintain the posture of the reference angle or the quasi-reference angle, so that the work vehicle is supported so that the position of the circular saw does not shift. Stable and uniform grinding can be performed only by itself.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of an embodiment, FIG. 2 is a partially omitted sectional view of the same as above, and FIG. 3 (a) shows a part of a single-sided circular saw. The plan view shown in the figure, the figure (b) is a sectional view taken along the line AA of the figure (a), the figure (a) of FIG. 4 is a plan view showing a part of the double-sided circular saw, and the figure (b) is the same. FIG. 5A and FIG. 6 are explanatory views of the reference angle, FIG. 7 and FIG. 8 are explanatory views of the quasi-reference angle, and FIG. 9 is the reference angle. Fig. 10 is a plan view of the embodiment in the case of Fig. 10, Fig. 10 is a sectional view showing a part of the case of Fig. 9, and Fig. 11 is a plan view of the embodiment in the case of a quasi-reference angle
FIG. 12 is a side view showing a part of the case of FIG. 11, FIG. 13 is a perspective view showing a part of another embodiment, and FIG. 14 is a sectional view of FIG. 1 ... Base, 2 ... Wheel, 3 ... Mounting base, 4 ... Bearing piece, 5 ... Shaft, 6 ... Support shaft, 7 ... Circular saw cradle, 8 ...
… Base, 9… Spring, 11… Stopper, 12… Circular saw holder, 13… Positioning member, 14… Positioning recess, 15…
… Positioning device.

Claims (2)

[Scope of utility model registration request] 1. A circular saw grinding jig which is mounted on a base 1 of a grinder and is provided with a mounting base 3 which is fixed in the vicinity of a grinding wheel 2 of a grinder, and a bearing piece is mounted on the mounting base 3. 4, a support shaft 6 protruding parallel to the shaft 5 of the grinding wheel 2 is fixed to the bearing piece 4, and the base portion 8 of the circular saw pedestal 7 is fixed to the fixed end of the support shaft 6 at a predetermined reference angle. It is rotatably inserted so as to obtain a reference angle, and the base 8 is pressed against either one of the bearing piece 4 and a part of the support shaft 6 by a spring 9, and a stopper 11 is slid in the middle of the support shaft 6 and It is rotatably inserted, and further, the circular saw holder 12 is slidably and rotatably inserted outside the stopper 11, and a positioning member 13 is provided on the inner surface of the circular saw holder 12 so as to project. The positioning recess 14 into which the positioning member 13 fits when the quasi-reference angle is taken A jig for grinding a circular saw, which is formed on the outer end surface of the stopper 11 of FIG. 2. The circular saw grinding jig according to claim 1, wherein the base portion 8 of the circular saw pedestal 7 inserted into the fixed end side of the support shaft 6 is either the bearing piece 4 or a part of the support shaft 6. In place of the structure in which the bearing piece 4 is pressed against the bearing piece 4, a positioning device 15 for selectively engaging the base portion 8 of the circular saw pedestal 7 with a predetermined position of the bearing piece 4 at the reference angle and the quasi-reference angle is provided on the bearing piece 4. Jig for circular saw grinding.