JP7817975B2 - Jig for precision wood processing - Google Patents

Description

The present invention relates to a jig for precision wood processing that can accurately cut wood at a set angle using a saw.

Automated equipment that precisely processes wood according to design drawings is widely used. However, large-scale, expensive automated equipment is not suitable for processing handmade furniture and decorative items. For example, to cut wood perpendicular to its surface, a screen-shaped jig such as that described in Patent Document 1 is used. In addition, Patent Document 2 introduces a saw-tooth cutting jig that holds a saw by clamping it between slits.

JP 2015-176098 A Utility Model Registration No. 3222994

For example, a craft project may involve assembling blocks several centimeters thick, as shown in Figure 8. Unless each block is cut with high precision to maintain flatness and parallelism on its cut surface, the joints between the blocks will not adhere tightly. For example, even a gap of 0.1 millimeters prevents the blocks from being assembled into the desired shape. This flatness (degree of inclination) must be 0.01 mm per centimeter or less. This type of work requires highly skilled, skilled craftsmen. If the cut surface is slightly inclined, the inclination can be corrected by grinding the surface to make it flat, but this process also requires high skill and consumes a significant amount of work time. The present invention addresses these issues and aims to provide a precision wood processing jig that can be used to cut wood at a set angle with high precision without requiring high skill.

The following configurations are each means for solving the above problems.

<Configuration 1>
a base 12 on which the wood 36 to be processed is placed;
Two support columns 14 are erected on the top surface of the base 12;
a reference plate 16 having one surface in close contact with the two support columns 14 and the other surface having a reference surface 17;
a resilient mechanism for resiliently pressing the reference plate 16 against the two support posts 14 to position the reference plate 16;
The reference surface 17 is a surface perpendicular to the top surface of the base 12, and has a magnet embedded therein that attracts the flat side of the saw.
A spacer 26 is further disposed on the reference surface 17 to limit the upward movement of the upper edge of the saw.
The jig for precision wood working is characterized by comprising a back plate which sandwiches a reference surface 17 and a spacer 26 to form a movement space for the saw blade of the saw.

<Configuration 2>
The jig for precision woodworking described in configuration 1 is characterized in that the clamp plate 18 is arranged so as to sandwich the two posts between the reference plate 16 and the clamp plate 18, the tips of two clamp pins 20 that pass through the clamp plate 18 are fixed to the reference plate 16 directly or via a reinforcing plate 48, springs 22 are fitted into the clamp pins 20, and the elastic mechanism of this structure applies elastic force so as to press the reference plate 16 against the posts 14.

With the precision wood processing jig of the present invention, even an unskilled craftsman can maintain the accuracy of the saw's cut surface inclination below the required level from the start to the end of the cut. Furthermore, the saw blade can be kept parallel to the top surface of the wood while cutting, preventing lateral movement of the saw blade and preventing chipping at the corners of the wood. This also simplifies the process of flattening the cut surface after cutting, significantly reducing work time.

1A is a perspective view of the jig for precision woodworking of the present invention, and FIG. 1B is a perspective view showing the relationship between the reference plate 16 and the saw 34. FIG. 1 is an exploded perspective view of a main part of a jig for precision wood processing according to the present invention. 1 is a side view showing a saw 34 cutting a piece of wood 36. FIG. 1 is a top view showing the relationship between the jig for precision wood processing of the present invention and the saw head 40. FIG. 1 is a side view showing the relationship between the jig for precision wood processing of the present invention and the saw head 40. FIG. 10 is an explanatory diagram of highly accurate cutting using a saw 34. FIG. FIG. 10 is a front view showing additional functions of the jig for precision wood processing of the present invention. FIG. 1 is a plan view of a wooden product that requires high-precision machining.

Embodiments of the present invention will be described in detail below, with examples.

The precision wood processing jig shown in Figure 1 includes a base 12 on which the piece of wood 36 to be processed is placed. In order to process the piece of wood 36 with high precision, the top surface of this base 12 is also flattened to the same extent as the surface of the piece of wood 36. In other words, in this example, the top surface of the piece of wood 36 placed on the base 12 is also processed parallel to the top surface of the base 12, and an example will be described in which the piece of wood 36 is precisely cut at a cross section perpendicular to the top surface of the piece of wood 36.

If you want to cut the wood 36 at a 45-degree angle to its top surface, you can place the wood 36 on a 45-degree angled platform (not shown) and secure it to the base 12. In this example, to obtain a cross section that is perpendicular to both the top surface and the side of the wood 36, the side of the wood 36 is pressed against the positioning block 50 during the cutting process. The position and angle of the positioning block 50 are also set for this purpose.

Two support posts 14 are erected on the top surface of this base 12, and a reference plate 16 is provided on one side in close contact with them, with the other side having a reference surface 17. The two support posts 14 are provided so that the wood 36 is sandwiched between them, and the saw can be positioned and supported from above with high precision to cut the wood 36.

The reference surface 17 is set and flattened so that it is precisely perpendicular to the top surface of the base 12. The surface where the support 14 and reference plate 16 come into contact is also flattened with high precision, so that no matter which surface of the support 14 the reference plate 16 is in contact with, the reference surface 17 is maintained precisely perpendicular to the top surface of the base 12.

The clamp plate 18 is positioned so that the two support posts are sandwiched between the reference plate 16 and the clamp plate 18. A reinforcing plate 48 is fixed to the surface of the reference plate 16 opposite the reference surface 17. This prevents bending of the reference plate 16 and increases its strength. The reinforcing plate 48 is positioned so that it is sandwiched between the support posts 14. Furthermore, the tips of two clamp pins 20 that penetrate the clamp plate 18 are fixed to the reinforcing plate 48. Springs 22 are fitted into the clamp pins 20, providing elasticity that presses the clamp plate 18 against the support posts 14. This constitutes an elastic mechanism that uses elastic force to press the reference plate 16 against the two support posts 14 to position it. This structure has the advantage that the elasticity can be easily adjusted and that excessive force is not applied when moving the reference plate 16 up and down.

The height of the reference plate 16 must be adjusted according to the shape of the wood 36. Furthermore, if the reference plate 16 is not lowered when the saw 34 is cutting the wood 36, the force with which the reference plate 16 holds the saw 34 vertically by suction will decrease. Even if the reference plate 16 is moved up and down, the reference surface 17 must always remain on the same plane. By providing an elastic mechanism that uses elastic force to press the reference plate 16 against the two supports 14 and move it up and down along the supports 14, the required positional accuracy can always be maintained.

As shown in Figure 1(b), magnets 32 that attract the flat side of the sawtooth 34 are embedded in the reference surface 17 of the reference plate 16. The attractive force of the sawtooth 34 is set to an optimal value depending on the number of magnets 32 and their embedding depth. If the attractive force is too strong, the sawtooth 34 becomes difficult to move, and if the attractive force is too weak, the flat surface of the sawtooth 34 will separate from the reference surface 17 when the sawtooth 34 is moved. It is best to determine the optimal value through experimentation. We also attempted a structure in which the sawtooth 34 is pressed against the reference surface 17 using a spring or the like, but it was difficult to apply an appropriate pressing force evenly across the entire reference surface 17, making this unpractical.

A spacer 26 is also placed on the reference surface 17 to limit the upward movement of the upper edge of the saw blade 34. The saw blade 34 comprises a handle 42 and a saw blade 40. The flat surface on the side of the saw blade 34 refers to the surface excluding the blade length 44 of the saw blade 40. The blade length 44 is thicker and not flat than the other parts of the saw blade 40. If this part were to come into contact with the reference surface 17, a gap would be created between the flat surface on the side of the saw blade 34 and the reference surface 17, causing the saw blade 34 to tilt. Therefore, the spacer 26 serves to prevent the upper edge of the saw blade 34 from moving upward.

As shown in Figure 1(a), if the width S of the reference surface 17 below the spacer 26 is shorter than the width W from the upper edge of the sawtooth 34 to the blade length 44, then the parts of the side of the sawtooth 34 other than the flat surface will not come into contact with the reference surface 17.

Furthermore, a back plate 28 is provided between the reference surface 17 and the spacer 26 to create a movement space for the saw blade of the saw. This is to prevent the flat surface on the side of the saw 34 from separating from the reference surface 17 due to the impact when the upper edge of the saw 34 hits the spacer 26. A more detailed explanation of the effect will be given using Figure 6.

Figure 2 shows an exploded view of the main components of the device of the present invention. Several circular magnets 32 are embedded in the reference plate 16. If the reference plate 16 is made of wood, holes for embedding the magnets 32 can be drilled and the magnets 32 can be secured in place with adhesive or similar. If the reference plate 16 is sufficiently strong, there is no need to use a reinforcing plate 48. In other words, it can be inserted through the clamp plate 18. The tips of the clamp pins 20 can be secured directly to the reference plate 16 with nuts 24 or similar. Various other structures have been tried, but this structure is considered the best design, allowing the reference plate 16 to be freely positioned and moved up and down while maintaining high precision.

The optimal spacer 26 is selected depending on the thickness of the saw blade 40 of the saw 34. Therefore, it is preferable to make the spacer 26 replaceable, for example by screwing it to the reinforcing plate 48. The back plate 28 is fixed to the reference plate 16 with the spacer 26 sandwiched between them. When cutting wood 36 with the saw 34, the wood 36 often has scribed lines drawn in advance at the areas to be cut. The back plate 28 has viewing grooves 30 in appropriate locations.

The scribed line can be viewed directly through this viewing groove 30, allowing one to confirm whether the blade length 44 of the saw 34 is directly above the line. This viewing groove 30 can also be provided on the reference plate 16 side. Furthermore, since the back plate 28 does not come into direct contact with the saw 34, high processing precision is not required. Therefore, for example, a transparent plastic plate would also do. If it is transparent, it is possible to view the scribed line on the wood 36 directly from the back plate 28 side.

Figure 3 shows the state in which the spacer 26, together with the reference plate 16, is gradually lowered from top to bottom along the support 14 as the saw 34 is cut. In any state, the blade length 44 of the saw 34 does not come into contact with the reference plate 16. The flat side of the saw blade 40 is always moved along the vertical plane set by the reference surface 17 of the reference plate 16. Furthermore, the saw 34 blade length 44 can be kept parallel to the top surface of the wood 36 from start to finish. This allows for cutting operations that are completely free of chipping, which often occurs at the beginning and end of a cut. This is an extremely useful effect when cutting soft woods such as cedar boards.

Figure 4 shows a top view of a saw 34 being used to cut a piece of wood 36. By fixing the piece of wood 36 on the base 12 and aligning it with the positioning block 50, the cutting surface of the piece of wood 36 can be positioned vertically and horizontally. This means that the piece of wood 36 can be cut at a right angle when viewed from above or from the side. Furthermore, if the piece of wood 36 can be placed on the base 12 at a 45-degree angle, for example, a cutting surface at a 45-degree angle can be created. Using various auxiliary stands to support the piece of wood 36 on the base 12 makes it possible to freely and accurately cut the piece of wood 36 at various angles.

The drawing in Figure 5 shows how the saw blade 40 of the saw 34 is positioned in the gap formed between the reference plate 16 and the back plate 28. That is, as shown in the figure, the flat side of the saw blade 40 is in close contact with the reference surface 17 of the reference plate 16, and in this state the wood 36 is cut. At this time, a small gap is created between the saw blade 40 and the back plate 28, which does not interfere with the operation of the saw blade 40. Furthermore, when the saw blade 40 collides with the spacer 26, the back plate 28 prevents it from recoiling and coming off the reference surface 17 of the reference plate 16.

The reason why the device of the present invention can cut wood with extremely high precision will be explained using the diagram in Figure 6. Figure (a) is a side view of the saw 34. As explained above, the saw 34 has a handle 42 and a saw blade 40, with a cutting edge 44 formed at the lower edge of the saw blade 40. Here, we will explain the case where the saw 34 is used to cut wood 36. Figure (b) is a cross-sectional view of the saw blade 40 while cutting wood 36. Generally, the saw blade 40 is thicker at the cutting edge 44. Because the saw 34 has this cross-sectional structure, when cutting wood 36 with the saw 34, the saw blade 40 can be moved without resistance while cutting.

While the gap between the saw head 40 and the wood 36 plays an important role, anyone will experience the cut surface becoming slightly curved as they continue to cut. If, as shown in (c), a vertical partition 52 is placed on top of the wood 36 and the saw head 40 of the saw 34 is supported against the partition as they continue to cut, a more stable cut surface can be obtained. This is a method introduced in Patent Document 1.

However, when the blade length 44 hits the side of the partition 52, the saw head 40 tilts slightly. This tilt is usually completely negligible. However, the precision machining jig of the present invention is used in applications requiring high precision where such tilting is not permitted. Figure (d) shows the saw guide described in Patent Document 2, in which the saw head 40 is sandwiched between two slits. A sufficiently narrow slit increases precision. However, when cutting wood 36, the saw head 40 of the saw 34 is subjected to alternating pulling and pushing forces. Because this causes the saw head 40 to oscillate sideways, unless the slit is sufficiently wide, it is difficult to move and the wood 36 cannot be cut. Ultimately, the saw head 40 tilts within the slit as shown, preventing a vertical cut surface from being obtained with sufficient precision.

(e) shows the operation of the precision machining jig of the present invention, which solves this problem. As shown in the figure, a magnet 32 is embedded in the reference plate 16, and the saw blade 40 of the saw 34 has its flat surface pressed against the reference surface 17 of the reference plate 16. When the saw 34 is moved in this state, the saw blade 40 can only move in a direction parallel to the reference surface 17, remaining in close contact with the reference surface 17. This allows the blade 44 to cut vertically from the start to the end of the cut on the wood 36 placed below. Furthermore, there is no lateral vibration, and the cutting can be performed while the blade 44 of the saw 34 remains parallel to the top surface of the wood 36.

For example, if the thickness of the saw blade 40 of the saw 34 used to cut the wood 36 is 0.5 mm, the thickness of the blade length 44 is approximately 0.7 mm. The width of the saw blade 40 is approximately 5 cm. The width of the groove created when cutting the wood 36 shown in Figure 6(b) is approximately 0.9 mm. If the groove is 3 cm deep, and the saw blade 40 tilts within this groove during cutting, it will tilt by a maximum of 0.45 mm over 3 cm.

Even in the case of (c), there is a tilt of 0.1 mm over 3 cm. The same is true for (d). With the precision machining jig of the present invention, cutting can be performed with a tilt of less than 0.01 mm per cm, and less than 0.03 mm over 3 cm. The piece shown in Figure 8 is 1 cm thick and 8 cm in diameter. If the joining surface is tilted by even 0.1 mm per cm, gaps will appear in various places, resulting in an irregular shape. Using the method described using (e), there is almost no tilt in the cut surface.

Diagram (f) shows a situation in which the saw blade 40 suddenly climbs over the spacer 26 above it while the saw blade 34 is in operation. If the thickness of the saw blade 34 is 0.5 mm, the thickness of the spacer 26 is approximately 1 mm. Therefore, there is a risk that the saw blade 40 will bounce over it during use. To solve this problem, the spacer 26 is sandwiched between the reference plate 16 and the back plate 28. As is clear from this drawing, the back plate 28 does not contact the saw blade 40. Therefore, the saw blade 40 does not come into contact with the back plate 28 through this gap, and there is no resistance when the saw blade 34 is in use.

As already explained, when cutting through the wood 36 with the saw 34, it may be necessary to gradually lower the reference plate 16 from top to bottom. Figure 7 shows an example of a mechanism for vertically moving the reinforcing plate 48 (Figure 1) used to reinforce the reference plate 16. As shown in Figure 7, a top plate 60 is fixed to the top of the support 14. A dial nut 62 is loosely fitted into the center of this top plate 60 so that it can rotate freely. It has a female threaded hole in the center into which a bolt 64 can be screwed. The bolt 64 is fixed to the top of the reinforcing plate 48. By rotating the dial nut 62 in this state, the reinforcing plate 48 can be easily moved vertically up and down.

If the dial nut 62 is loosely fitted into the top plate 60, moving the reinforcing plate 48 up and down will not apply unnecessary force to the reference plate 16 fixed to the reinforcing plate 48. In other words, the reference plate 16 can be moved up and down while always being pressed against the support 14 by the above-mentioned elastic mechanism. Furthermore, if the elasticity of the elastic mechanism is appropriate, it will not move when you operate the saw 34, but it is possible to grasp the reference plate 16 with both hands and move it straight up and down with the force of your hands. The mechanism for moving the reference plate 16 up and down in this embodiment has the advantage that it can be operated with one hand without applying force. With the above configuration, wood 36 can be cut easily and accurately with the saw to the required precision.

12 Base 14 Support 16 Reference plate 17 Reference surface 18 Clamp plate 20 Clamp pin 22 Spring 24 Nut 26 Spacer 28 Back plate 30 Viewing groove 32 Magnet 34 Saw 36 Wood 38 Guide plate 40 Saw body 42 Handle 44 Blade length 48 Reinforcement plate 50 Positioning block 52 Partition 54 Saw guide 60 Top plate 62 Dial nut 64 Bolt

Claims (2)

A base on which the wood to be processed is placed,
Two supports are erected on the top of this base,
a reference plate having one surface that is in close contact with the two support posts and the other surface that has a reference surface;
a resilient mechanism for pressing the reference plate against the two support posts by resilience to position the reference plate;
The reference plane is a plane perpendicular to the top surface of the base, and has a magnet embedded in it that attracts the flat side of the saw.
a spacer is further disposed on the reference surface to limit upward movement of the upper edge of the saw;
This jig for precision woodworking is characterized by having a back plate that sandwiches a reference surface and a spacer to form a movement space for the saw blade of the saw. The jig for precision wood processing described in claim 1, characterized in that the clamp plate is positioned so that two support posts are sandwiched between the reference plate and the clamp plate, the tips of two clamp pins that pass through the clamp plate are fixed to the reference plate directly or via a reinforcing plate of the reference plate, springs are fitted into the clamp pins, and the elastic mechanism of this structure applies elastic force so as to press the one surface of the reference plate against the support posts.