JPH0857712A - Saw - Google Patents

Abstract

PURPOSE: To provide a circular sawing machine changeable between a chop sawing mode and a bench sawing mode, wherein favorable means is provided for controlling the cutting depth of a circular sawing blade in the bench sawing mode. CONSTITUTION: A saw assembly is placed above a table 12 at a first position on the table 12 so that a saw 10 serves as a chop saw for applying plunge cut to a workpiece supported on the first side face of the table 12. The saw assembly is placed under the table 12 at a second position on the table 12 so that the saw 10 serves as a bench saw for applying cutting to the workpiece through which a blade 26 is passed on the second opposite side face of the table 12. A parallelogram lever 34 has a pivotal member 14 and a connection capable of turning around an upper guard 32. The extension 118 of the lever 34 is provided with a rack 150 which is engaged with a worm gear 152 capable of rotating with a knob 156 in a bench sawing mode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a table, a pivot member on the table, and a saw assembly that is swiveled with respect to the pivot member about a pivot axis. It concerns a circular saw of the type in which the carrying saw assembly described above can be plunged into a workpiece supported on a table.

[0002]

2. Description of the Prior Art Saws of this kind are known and are known from European patent EP 013366.
6 and EP 0450400. These saws are useful, and these saws, not to mention the cleanliness and safety of equipment placement,
There are many possibilities to improve capacity, capacity and efficiency. On the other hand, all of these features add complexity and cost and can be inconvenient for the saw user.

The invention is in particular a saw of the type described above, yet it further allows the table to be inverted so that the saw assembly lies below the table, for example by pivoting about an axis. To a saw having a table mounted in a frame. The table is further provided with a slit so that the blade can project through this slit to make the saw look like a bench or table saw. Such saws are known from West German patent DE 16 28 992 and European patent EP 050235.
No. 0.

Both the aforementioned European patents EP0133666 and EP0450400 describe a saw in which the saw assembly comprises an upper guard and a lower guard for the blade. The upper guard is formed from the saw assembly housing, which permanently covers the top portion of the blade. The bottom part of the blade is covered by the lower guard. However, this lower guard must be retracted in use so that the blade is exposed when needed to perform the cutting operation.

A handle is located on the upper guard which allows the user to pivot the saw assembly up and down to perform a cutting operation on a work piece supported on a table. The lower guard can be opened completely by means of an actuating lever arranged on the handle mentioned above. Alternatively, the lower guard can be opened automatically by pivoting the saw assembly, in which case a connection is provided between the lower guard and the pivot member for this purpose. As a further alternative, the lower guard can be partially opened by any of the arrangements described above and only further opened by direct contact with the workpiece.

Although not explicitly mentioned in European patent EP 0450400, the saw to which this European patent specification relates uses a parallelogram lever arrangement. The upper guard is pivoted with respect to the saw assembly. A parallelogram lever extends between the upper guard and the pivot member, and the parallelogram lever comprises a pivot axis of the upper guard relative to the saw assembly,
It is parallel to the line connecting the pivot member with the pivot axis of the saw assembly. This arrangement helps maintain the orientation of the upper guard with respect to the pivot member, and thus the orientation of the upper guard with respect to the table. In addition to the small benefit when the saw is in chop saw mode, a major benefit is given when the saw is in bench saw mode. This is a ripping knife (rivi when the saw is in bench saw mode.
ng knife) is attached to the upper guard,
It is important that the tip of the split knife is approximately level with the top of the saw blade. It is necessary that the tear knife be located above the blade if the workpieces to be cut should be completely separated. In this case, when a so-called pocket cut is made, i.e. when the groove is cut into the workpiece, the guard is usually placed above the blade height position or just below the blade height position on the knife. It is attached. In any case, the orientation of the knife with respect to the blade should be kept constant for all positions of the blade, which is why parallelogram arrangements are often used.

Of course, in the bench saw mode of the saw,
It is necessary to provide different positions of the blade with respect to the table, i.e. different amounts of protrusion of the blade through the slits in the table and hence different cutting depths of the blade. The blade should protrude through the slit only enough to leave a small portion of the blade above the workpiece (assuming complete separation of the workpiece is required), so that the blade is always It is well known that the uppermost number of teeth should be in contact with the workpiece. For pocket cutting, more precise adjustment of the cutting depth is required.

It is an object of the present invention to provide a convenient means of adjusting the cutting depth of a saw of the type described above.

[0009]

According to the present invention, a saw is a frame, a table mounted in the frame and adapted to assume two positions, and on a first side of the table. The pivot member includes a pivot member, a saw assembly that is swiveled with respect to the pivot member, a blade supported in the saw assembly, a motor that drives the blade, and an upper guard that covers an upper portion of the blade. It is pivotally mounted to the saw assembly and further comprises a slit in the table such that the blade projects through this slit, and in the first of the above two positions of the table, A saw assembly is located above the table so that the saw forms a chop saw for making a plunge cut on a work piece supported on the first side of the table, among the two above-mentioned positions of the table. Saw in the second position of The body is located below the table, so that the saw forms a bench saw for making a cut on the workpiece through which the blade is passed on the second opposite side of the table, and also the parallelogram lever. The parallelogram lever has a pivotable connection to the pivot member and the upper guard, thereby maintaining the orientation of the upper guard with respect to the pivot member, and further comprising an extension of the parallelogram lever. The extension cooperates with the pivot member via the adjusting means when the saw assembly is in its second position so that the position of the saw assembly relative to the pivot member is controlled by the adjusting means. Saw has been provided.

Thus, here the parallelogram lever maintains the orientation of the upper guard with respect to the pivot member, and thus the orientation of the upper guard with respect to the table, and the depth of cut of the blade when in bench saw mode. It has two functions, the function of controlling the height. The latter function is achieved by the movement of the parallelogram lever itself being controlled by the adjusting means.

Preferably, the adjusting means comprises a worm gear rotatably mounted in the carrier member, the carrier member being adjustably connected to the pivot member, preferably pivotably mounted, and said extension being a worm gear. The rotation of the worm gear when engaged with the rack is such that the protrusion of the blade through the slit is caused by pivoting the parallelogram lever around the pivot of the parallelogram lever with respect to the pivot member. Help to change.

Means must be provided under all reasonable circumstances to bias the saw assembly toward a raised and upright position when the saw assembly is at rest in chop saw mode, As a result, the user must not be required to lift the insignificant weight of the saw assembly after completing the plunge cut. Such means typically take the form of strong springs.

However, a problem occurs when the table is turned over to convert the saw into a bench saw. The weight of the saw assembly now acts in the opposite direction to the table, while the spring or other biasing means usually acts in the same direction. Further, in bench saw mode, the saw assembly is plunged into the table (before the table is turned over) so that the blades project all the way through the slits. This helps to further tension the spring and exacerbates the problem of adjusting the depth of cut. That is, not only must the adjusting means be able to withstand the weight of the saw assembly, but the adjusting means now copes with the extra force exerted by the spring means acting in the same direction as the weight of the saw assembly. Must.

The adjustment device provided by the present invention is adapted to be conveniently operated by a user. In chop saw mode, the pivot member is typically located behind the saw, leaving the saw's "mouth" (ie, the gap between the saw assembly and the table) facing forward. However, if the saw is turned back into bench saw mode, the pivot member is now located below the table and in front of the saw. The adjusting means can thus be easily accessed by the user in front of the saw. However, in addition to access, it is desirable to have a knob or handle that achieves adjustment between minimum and maximum depth of cut in just a few turns.

However, if the weight of the saw and the action of the spring biasing means (acting in its most tensioned position) have to be accommodated, this is usually a fine form of adjustment, ie much It means that a gear-decelerated type of adjustment must be used. Because the saw assembly has to be lifted against the weight of the saw assembly itself and the spring bias pressure, the coarse form is difficult to operate (in one direction) and the coarse form is This is because it may be steep in the other direction.

Thus, according to the invention, the saw has spring means between the pivot member and the saw assembly for biasing the saw assembly away from the table, the spring means comprising the pivot member and the saw member. Acting on an intermediate element arranged between the assemblies, the intermediate element has two positions, in a first of these two positions the spring means are sawed when the table is in the first position of the table. Supports the weight of the assembly and is the second of the above two positions
A further improvement is provided in that the position is substantially eliminated from the biasing force described above.

Thus, the use of the saw according to the invention in bench saw mode eliminates the additional effect of the spring means on the depth of cut adjustment, so that it would be possible otherwise. A coarser form of adjustment can be used. The above-mentioned intermediate element may comprise a toggle lever pivotally mounted on the pivot member, which toggle lever tensions the spring means in the above-mentioned first position of the intermediate element and the toggle lever comprises the intermediate lever. The second of the element
Releasing said tension when pivoting to a position and pivoting said carrier to engage said extension.

The carrier and the toggle lever described above can be swiveled around the same axis in the pivot member. The spring means may include a torsion spring about the pivot axis of the saw assembly in the pivot member, one end of the torsion spring pressing the saw assembly and the other end of the torsion spring serving as a toggle lever. Engage. An intermediate lever can be arranged between the other end of the torsion spring and the toggle lever.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. Referring first to FIG. 1, a saw 10 according to the present invention comprises a table 12 having a pivot member 14 on which a saw assembly 16 is pivotally mounted about an axis 18.

The saw assembly 16 comprises a housing 20 in which a motor 22 having an axis of rotation 24 is mounted. The motor 22 has a circular saw blade 26 mounted in the housing 20.
Are driven around the axis 28 via a drive connection by a belt 30. An upper guard 32 is mounted within housing 20 pivotably about axis 28. The upper guard 32 is connected to the pivot member 14 by a parallelogram lever 34, which is pivoted at both ends about axes 36, 38. The line connecting the axes 36 and 38 is parallel to the line connecting the axes 18 and 28.

Similarly, a lower guard 40 is pivotally mounted within housing 20 about axis 28. The lower guard 40 is opened by an actuator lever (not shown) to expose the blade 26. Thus, when the lower guard 40 is opened and the blade 26 is exposed,
The saw assembly 16 can swivel downward about the axis 18 and thus hit the table 42 while hitting the fence 42.
The blade 26 may be adapted to plunge into a work piece (not shown) supported on 2. The table 12 has a slit (not shown) through which the blade 26 passes as the saw assembly 16 pivots downward to the position shown in FIG.

The parallelogram lever 34 has a pivot member 1
4, maintaining the orientation of the upper guard 32 with respect to 4, and thus the orientation of the upper guard 32 with respect to the table 12. 1 to 4 the saw 10 is shown in four positions, in which the lower guard 4 is shown.
0 is located in four different positions.

The parallelogram lever 34 has a lower guard 40.
Has an extension portion 35 that abuts the top surface 101 of the flange 100. According to the geometrical analysis of this arrangement, the extension 35
The saw assembly 16 is shown in FIG.
It can be seen that it is not possible to turn downward about the axis 18 from the position shown in FIG. This forms a lock which is released by opening the lower guard 40 to the position shown in Figure 2 by the actuator lever described above. In the position shown in FIG. 2, the flange 100 has moved out of the bottom of the extension 35, so that the saw assembly 16 is now allowed to pivot about the axis 18.

In FIG. 3, the saw assembly 16 is a fence 42.
It is swung downward about the axis 18 so as to cut the workpiece placed on the table 12 while hitting. Figure 2
The extension 3 between the position shown in FIG. 3 and the position shown in FIG.
5 engages the cam surface 103 of the flange 100 so that downward movement of the saw assembly 16 causes the lower guard 40 to open further. In FIG. 4, the lower guard 40 is completely retracted inside the upper guard 32.

The saw 10 described thus far is a chop saw. However, the table 12 is preferably mounted within the frame to allow the table 12 to be inverted. A suitable mechanism for this arrangement is described in British Patent Application No. 9218363. The arrangement shown in EP 0 502 350 or the arrangement shown in West German patent DE 1628992 is also sufficient.

In FIGS. 5 and 6, saw 10 is shown in an inverted state for use as a bench saw.
In this bench saw condition, the blade 26 projects through a slit (not shown) in the table 12. Two distinctive actions are taken before the table 12 is turned over.
In the position shown in FIG. 1, a riving knife
fe) 110 is rotated about axis 112 by 180 °. This causes the split knife 110 to rip-sa in the bench saw mode shown in FIGS. 5 and 6.
Brought to a valid position for wing). Obviously the knife 110 cannot be rotated about the axis 112 when in this position. Second, when in the position shown in FIG. 1, the spring release toggle lever 114 is actuated as described below, resulting in a spring pressure that biases the saw assembly 16 toward the saw rest position shown in FIG. To release
At the same time, the worm gear carrier 116, which will be described later, is engaged with another extension 118 of the parallelogram lever 34. This means that the saw assembly 16 is shown in FIGS.
Serves to lock in the position shown in FIG. 1 and thus the saw assembly 16 can be turned over in this direction.

Referring now to FIGS. 7-9, the saw assembly 1
The housing 6 of 6 has a sleeve 120 rotatably mounted on an axis 122 of the pivot member 14 so as to form a pivot axis 18. A torsion spring 124 is wrapped around the sleeve 120,
One end 126 abuts the housing of the motor 22 which is connected to the housing 20 of the saw assembly 16. The other end 128 of the torsion spring 124 is pivotally attached to the intermediate lever 132 about an axis 130. The other end of the intermediate lever 132 is attached to the toggle lever 114 so as to be rotatable about the axis line 134. Toggle lever 1
14 is attached to the pivot member 14 so as to be rotatable about an axis 136. In FIG. 7, toggle lever 114 is shown in its first position. The toggle lever 114 is located in this first position when the saw 10 is used as a chop saw as shown in FIGS. Here, the toggle lever 114 is rotated clockwise to its maximum range, at which time the heel portion 140 of the toggle lever 114 contacts the motor housing 22. In this position, the torsion spring 124 is fully tensioned so that the end 126 of the torsion spring 124 is at the saw assembly 16.
Can support the weight of.

When the knob 142 (see FIG. 9) is pushed as will be described later, the toggle lever 114 can be rotated in the counterclockwise direction, and the tension of the torsion spring 124 is gradually released. During this operation, it is preferred that the user slowly lower the saw assembly 16 into the table 12 while supporting the weight of the saw assembly 16. Toggle lever 1 shown in FIG.
In the second position of 14, the legs 14 of the toggle lever 114 are
4 contacts the heel portion 146 of the worm gear carrier 116 and engages the worm gear carrier 116 with the rack 150 formed on the end of the extension 118 of the parallelogram lever 34. The rack 150 engages the worm gear carrier 116 when the saw assembly 16 is lowered near the table 12 and just before the blade 26 enters the slit in the table 12.

Next, referring to FIGS. 10 (a) and 10 (b), the worm gear carrier 116 is the worm gear 1
The worm gear 152 is carried by the knob 156 formed on one end of the worm gear 152 and is rotatable about the longitudinal axis 154 in the worm gear carrier 116. Rack 15 as shown in FIG.
When engaged with 0, rotation of knob 156 causes worm gear 152 to rotate and rack 150 to move about axis 154.
Direction and pivot the parallelogram lever 34 about its axis 38 with respect to the pivot member 14, thus raising and lowering the saw assembly 16 relative to the table 12. Since the tension of the torsion spring 124 has already been released, the weight of the saw assembly 16 is the only weight of the worm gear 1.
Needed to be supported by 52. This worm gear 152 can therefore have a relatively coarse thread, so that the cutting depth of the blade 26 protruding through the table 12 between the position shown in FIG. 5 and the position shown in FIG. 6 is adjusted. Only a few turns of knob 156 are required to do. However, if the torsion springs 124 were still fully tensioned, the load on the worm gear 152 and the levers 34, 1
The load on 18 more than doubles and such a rough thread would not be practical.

Moving the toggle lever 114 between its two positions requires the release of the lock. If no lock was provided, inadvertent release of toggle lever 114 from the position of toggle lever 114 shown in FIG. 7 could have dire consequences. Any type of lock can be used, but FIGS.
1 shows one suitable embodiment.

Axis 136 is formed by shaft 158 attached to pivot member 14 by screws 160. Worm gear carrier 116 is free to pivot on shaft 158. The shoulder 164 of the shaft 158 holds the collar 166 of the toggle lever 114 on the shaft 158. Toggle lever 1
Fourteen holes 168 receive the knob 142 described above. Knob 1
42 has four splines 170 which engage corresponding slits in holes 168,
As a result, the knob 142 moves around the shaft 158 and the toggle lever 11 moves.
4 is constrained to rotate with. However, the shaft 158 itself is provided with a short splined portion 162, and the hole 172 of the knob 142 is similarly provided with a corresponding splined portion 174.

Knob 142 is provided with a spring 176 so that the knob 142 shown in FIG.
It is biased toward the position shown in (a). Figure 10
At the position shown in (a), the splined portion 162 of the shaft 158 and the splined portion 174 of the knob 142 are aligned (see FIG. 11 (a)). Thus, the toggle lever 114 is rotationally locked on the shaft 158. However, when the knob 142 is pushed down while compressing the spring 176, the splines 162 and 174 are disengaged and the toggle lever 114 can be rotated (see FIGS. 10 (b) and 11 (b)). .

Finally, referring again to FIGS. 7 and 8,
In the raised rest position, the ends of the torsion spring 124 form an angle of about 90 ° with each other.
Are twisted and arranged. An additional 45 ° or more can be added during pivoting to the position shown in FIG. It can be seen that the spring force acts between axis 130 and axis 134, which tends to rotate toggle lever 114 clockwise. In this position, the heel 140 abuts the motor 22, and in any case the line connecting the axis 130 and the axis 134 is very close to the axis 136, so even at the maximum spring compression the toggle lever 1
The torque on 14 is extremely small.

On the other hand, in the position shown in FIG. 8, the torsion spring 124 is arranged so that it is completely free, so that there is no residual torque on the toggle lever 114. Further, when the toggle lever 114 is actuated again to tension the torsion spring 124 from the position shown in FIG. 8, the line connecting the axes 134 and 130 again causes the torsion spring end 128 to rotate clockwise about the axis 18. Helps to rotate around. Initially only a small torque can be applied (because this line is close to the axis 18), but the torsion spring 124 is free and exhibits little resistance.

[Brief description of drawings]

FIG. 1 is a side view showing a first position of a saw according to the present invention in a chop saw mode.

FIG. 2 is a side view showing a second position of the saw according to the present invention in a chop saw mode.

FIG. 3 is a side view showing a third position of the saw according to the present invention in a chop saw mode.

FIG. 4 is a side view showing a fourth position of the saw according to the present invention in the chop saw mode.

FIG. 5 is a side view of the saw shown in FIGS. 1 to 4 in a first position in bench saw mode.

FIG. 6 is a side view showing a second position of the saw shown in FIGS. 1 to 4 in a bench saw mode.

FIG. 7 is a side view showing a first position of the spring releasing device according to the present invention.

FIG. 8 is a side view showing a second position of the spring releasing device according to the present invention.

9 is a view taken along the arrow IX in FIG.

10 is a view taken along arrow X in FIG.
(A) is a state where the knob is pushed up by a spring,
Each of (b) represents a state in which the knob is pushed down.

11A is a sectional view taken along line AA of FIG. 10A, and FIG. 11B is a sectional view taken along line BB of FIG. 10B.

12 is a sectional view taken along line XII-XII in FIG.

[Explanation of symbols]

 10 ... Saw 12 ... Table 14 ... Pivot member 16 ... Saw assembly 20 ... Housing 22 ... Motor 26 ... Blade (circular saw blade) 32 ... Upward guard 34 ... Parallelogram lever 35 ... Extension 40 ... Downward guard 110 ... Tear knife 114 ... Toggle lever 116 ... Worm gear carrier 118 ... Extension 124 ... Torsion spring 132 ... Intermediate lever 142 ... Knob 150 ... Rack 152 ... Worm gear 156 ... Knob

Claims (9)

[Claims] 1. A saw, a frame, a table mounted in the frame and adapted to assume two positions, a pivot member on a first side of the table, and the pivot member on the pivot member. The saw assembly includes a saw assembly pivoted relative to the saw assembly, a blade supported in the saw assembly, a motor for driving the blade, and an upper guard covering an upper portion of the blade, the upper guard including the saw assembly. Pivotably attached to the body and further comprising a slit in the table, the blade projecting through the slit, and in a first of the two positions of the table, The saw assembly is located above the table so that the saw forms a chop saw for making a plunge cut on a work piece supported on the first side of the table, the two positions of the table In the second position inside the saw assembly The body is located below the table, so that the saw forms a bench saw on the second opposite side of the table for making a cut on the workpiece through which the blade is passed, and also the parallelogram. A lever, the parallelogram lever having a pivotable connection to the pivot member and the upper guard, thereby maintaining the orientation of the upper guard with respect to the pivot member, and further comprising the parallelogram A lever extension, wherein the extension cooperates with the pivot member via adjustment means to adjust the position of the saw assembly relative to the pivot member when the saw assembly is in its second position. A saw adapted to be controlled by adjusting means. 2. The adjusting means comprises a worm gear rotatably mounted in a carrying member, the carrying member being adjustably connected to the pivot member, and the extension portion including a rack for engaging the worm gear. The rotation of the worm gear when engaged with the rack causes the parallelogram lever to pivot about the pivot of the parallelogram lever with respect to the pivot member to project the depth of protrusion of the blade through the slit. The saw of claim 1, which helps to change the. 3. Spring means is provided between the pivot member and the saw assembly for biasing the saw assembly away from the table, the spring means being disposed between the pivot member and the saw assembly. Acting on the intermediate element, the intermediate element having two positions, the first of the two positions having the spring means of the saw assembly when the table is in the first position of the table. A saw according to claim 1 or 2, wherein the saw bears weight and the biasing force is substantially eliminated in a second of the two positions. 4. The carrying member is pivotally mounted to the pivot member and the intermediate element comprises a toggle lever pivotally mounted to the pivot member, the toggle lever being in a first position of the intermediate element. Wherein the spring means is tensioned and the toggle lever relieves the tension when pivoting to the second position of the intermediate element and pivots the carrier to engage the extension. The saw according to Item 3. 5. The saw according to claim 4, wherein the carrier and the toggle lever are pivoted about the same axis within the pivot member. 6. The spring means comprises a torsion spring around the pivot axis of the saw assembly in the pivot member, one end of the torsion spring pressing the saw assembly and the other end of the torsion spring being 5. Engage with a toggle lever.
Or the saw according to 5. 7. The saw according to claim 6, wherein an intermediate lever is disposed between the other end of the spring and the toggle lever. 8. The other end of the spring is pivotally attached to the intermediate lever about a first axis, the intermediate lever pivotally attached to the intermediate element about a second axis, An intermediate element is pivotally mounted on the pivot member about a third axis, the axes being parallel to each other and the line connecting the first axis and the second axis being the first position of the spring. The saw according to claim 7, wherein the saw is located on one side of the third axis and on the other side of the third axis in the second position. 9. A saw as claimed in any one of claims 3 to 8, wherein the spring means is neutral in the second position.