JPH0512082B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field> The present invention is a swing-type cutting method in which a loop-shaped band saw blade, which is wound around a pair of left and right saw wheels, swings in a cutting plane to make a cut. Regarding band saw machines.

<Conventional technology> Generally, in a band saw machine using an oscillating cutting method, the cutting length is short because the band saw blade partially contacts the cutting line of the workpiece, and the saw blade tends to slip upward against the workpiece. This has the advantage of shortening cutting time.
Since it is particularly effective for difficult-to-cut materials, several devices have been proposed, but none have yet been found to be fully satisfactory.

In other words, conventional systems that obtain rocking motion using two crank mechanisms installed on the left and right sides of the saw frame, however, when a basic and simple crank mechanism is used, the cutting trajectory is limited due to mechanical constraints. As shown in Figure 5, the shape of the saw blade is not a proper arc, but both the left and right inclined parts are almost straight lines, and only the central part is an arc, and the contact (cutting length) of the saw blade with the workpiece is continuous. There was an imperfection in that the same length was not ensured. In order to eliminate this imperfection and keep the cutting length the same, a complicated crank mechanism or a separate combination of other mechanisms is required, which makes the structure extremely complicated and expensive. There was a problem that I couldn't get it.

In addition, in the conventional method of obtaining an oscillation curve using curved guide grooves provided on the left and right sides of the upper part of the saw frame, there is a considerable distance between the guide groove and the cutting action part of the saw blade, so the main component of cutting force is (Component force in the direction of the cutting action line)
A huge moment of force acts on the guide groove, causing a twisting effect, and the saw frame cannot be sufficiently restrained from moving from side to side, resulting in chattering of the saw frame and other problems that prevent smooth oscillating cutting. I had a flaw that was difficult for me to understand. The causes of the above-mentioned twisting action and chatter phenomenon are unavoidable due to the structure of the above-mentioned crank mechanism system.

Furthermore, the conventional saw frame has a horizontal guide groove on the extension of the cutting line of action of the saw blade and servo cylinders are arranged on the left and right sides of the saw frame, but the structure is complicated and expensive. There was a problem.

<Purpose of the Invention> The present invention has been made to solve the above problems, and uses a simple mechanism to easily perform swing cutting with a correct arcuate cutting trajectory without twisting or chatter. The purpose is to provide a band saw machine that can perform

<Structure of the Invention> The present invention is characterized by either an elevating frame that moves up and down relative to a vise that fixes a workpiece, and a saw frame that is equipped with a pair of left and right saw wheels for running a band saw blade. On the one hand, there is a vertical guide groove that extends in a direction substantially perpendicular to the line of cutting action of the band saw blade, and a horizontal guide groove that causes the band saw blade to have a medium-high curved cutting locus above the vertical guide groove. In addition to providing direction guidance, on the other hand,
A pin that is slidably inserted into the two guide grooves is installed, and an active expansion/contraction means for connecting the saw frame and the lifting frame is provided in a substantially tangential direction of the lateral guide groove, and the active expansion/contraction means is installed. The saw frame is configured to perform a swinging motion with respect to the elevating frame by driving the means, which is regulated by the longitudinal guide groove and the lateral guide groove.

<Function> Most of the main cutting force is absorbed by the vertical guide groove that extends in a direction perpendicular to the line of cutting action of the bandsaw blade and the pin that is inserted into the guide groove. As a result of controlling the horizontal displacement of the saw frame, no vibration occurs during cutting, and at the same time, the moment due to the main cutting force does not act on the lateral guide groove or the pin inserted therein, and no twisting occurs.

In addition, since the locus of this swinging motion is determined by the shape of the lateral guide groove, by appropriately determining the shape through drawing or calculation, a correct arc-shaped locus of motion can be easily obtained. A correct arc-shaped motion trajectory can be obtained more easily than when using a crank mechanism.

<Example> Examples of the present invention will be described below based on the drawings.

FIG. 1 is a front view of an embodiment of the present invention, and FIG. 2 is a right side view thereof.

An elevating frame 4 is slidably supported by main and sub columns 2 and 3 provided upright on a base 1. This elevating frame 4 is driven up and down by an elevating cylinder 5 disposed behind the main column 2.

The saw frame 6 pivotally supports a drive wheel 7 that is rotatably driven by a motor (not shown) and a rotatable driven wheel 8, and a loop-shaped band saw blade 9 is hung between these wheels 7 and 8. It is rotated and driven to travel.

The saw frame 6 has a cutting action line 9a of the band saw blade 9.
A vertical guide groove 10 extending in a direction perpendicular to the line and a horizontal guide groove 11 are formed above the vertical guide groove 10. As will be described later, a pin 13 installed in the lifting frame 4 is inserted into this lateral guide groove 11 to regulate the direction of displacement of the saw frame 6 so that the cutting trajectory by the band saw blade 9 is in a correct circular arc shape. As shown in FIG. 1, it is a groove that extends in an arc shape approximately centered on the workpiece W, and is lower on the right side and has an upwardly convex curve. The curved shape of this lateral guide groove 11 cannot be uniquely expressed due to the dimensions of each part in the design, such as the positional relationship between the arrangement position of this groove 11 and the cutting action line 9a of the band saw blade 9. In order to ensure that the cutting locus of the bandsaw blade 9 is properly arcuate, it is desirable to obtain this curved shape by drawing or calculation.

Now, the elevating frame 4 has vertical guide grooves 10.
A pin 12 that is slidably inserted into the lateral guide groove 11 and the above-mentioned pin 13 that is also slidably inserted into the lateral guide groove 11 are implanted.

A swing cylinder 14 is disposed substantially tangentially to the lateral guide groove 11 so as to connect the lifting frame 4 and the saw frame 6. The swinging cylinder 14 is a double-acting clevis-mounted hydraulic cylinder, and has a cylinder end cover end attached to the elevating frame 4 and a piston rod end attached to the saw frame 6, and a solenoid valve in a hydraulic circuit (not shown). By switching, the piston is reciprocated in a desired cycle. This reciprocating movement causes the saw frame 6 to move against the pin 12 with respect to the lifting frame 4.
and 13, and a regulated rocking motion is provided by the vertical and horizontal guide grooves 10 and 11. As described above, this swing motion trajectory is mainly determined by the shape of the lateral guide groove 11.
The front view shown in FIG. 1 shows the saw frame 6 at one end of its oscillating movement, and at the other end as shown in FIG.

When the lifting cylinder 5 gradually lowers the lifting frame 4 and gives the saw frame 6 the above-mentioned swinging motion, the cutting action line 9a of the bandsaw blade 9 changes to the fourth line of action.
The cut is made while swinging like a seesaw between 9a() and 9a() shown in the figure, and by setting the shape of the lateral guide groove 11 appropriately by drawing etc. , a correct arc-shaped cutting curve A is formed on the workpiece W clamped by the vise 15 on the base 1.

During such cutting, chatter and twisting phenomena do not occur in the embodiments of the present invention. That is, the main cause of chattering or twisting of the saw frame 6 during cutting is the displacement of the saw frame 6 in the left-right direction due to the main cutting force acting on the band saw blade 9 (component force in the direction of the cutting action line 9a). However, according to the embodiment of the present invention described above, the longitudinal guide groove 10 bored in the saw frame 6 extends on the extension line of the cutting action line 9a of the band saw blade 9 in a direction substantially perpendicular to the line. Therefore, almost all of the main cutting force is applied to this vertical guide groove 10.
Since the saw frame 6 is received by the pin 12 through the saw frame 6, horizontal displacement of the saw frame 6 cannot occur. Therefore, no moment is generated in the lateral guide groove 11 due to the principal cutting force, and smooth rocking motion without chatter or twisting is performed. Note that the cutting back force (component force in the direction perpendicular to the cutting action line 9a)
is received by the pin 13 via the lateral guide groove 11.

In the above embodiment, the vertical and horizontal guide grooves 10 and 11 are provided on the saw frame, and the pins 12 and 13 are provided on the lifting frame 4, but conversely, the lifting frame 4 is provided with guide grooves and the saw frame is provided with guide grooves 10 and 11. A pin may also be provided.

Further, the horizontal guide groove 11 is not limited to the position directly above the vertical guide groove 10 as described in the above embodiment.
It may be provided further to the left, for example near the upper part of the workpiece W.

Furthermore, the elevating frame 4 is connected to the main and sub columns 2 and 3.
Instead of being swingably supported by the base 1, one of the lower ends may be pivotally supported on the base 1 in the form of a hinge so that the base 1 can be raised and lowered.

Furthermore, the swinging cylinder 14 can be replaced with another active expansion/contraction mechanism such as an electric screw.

In addition, in the present invention, "gradually lowering the elevating frame" means giving a descending feed to the extent that cutting can be performed, and the descending feed means:
Feeding means known in cutting, such as constant speed feeding,
This can be carried out by feeding with cutting resistance as a variable, feeding near the completion of one swing process, etc.

<Effects of the Invention> As explained above, according to the present invention, either the saw frame or the lifting frame is provided with a longitudinal direction extending substantially on the extension of the cutting action line of the band saw blade and in a direction substantially perpendicular to the line. A guide groove is provided, and a lateral guide groove is provided above the groove to generate an arc-shaped cutting trajectory of the bandsaw blade, and a pin is provided on the other side to be slidably inserted into the two guide grooves. The main cutting force is transmitted by the vertical guide grooves and the pins. This prevents the saw frame from being displaced in the left-right direction, and does not cause twisting or chatter during cutting.

Also, since the swing locus of the band saw blade is determined based on the shape of the lateral guide groove, the shape of this guide groove should be set appropriately by drawing or calculation based on the dimensions of each part of the band saw machine. As a result, compared to a band saw machine that uses a crank mechanism to perform rocking motion,
It becomes possible to easily provide a correct arcuate trajectory based on a simple mechanism.

[Brief explanation of the drawing]

Fig. 1 is a front view of the embodiment of the present invention, with the saw frame 6 at one swing end, Fig. 2 is a right side view thereof, and Fig. 3 is a view showing the saw frame 6 at the other swing end. FIG. 4 is a front view of the embodiment of the present invention showing a certain state, FIG. 4 is an explanatory diagram of the operation of the embodiment of the present invention, and FIG. 5 is an explanatory diagram of a cutting locus in a conventional oscillating band saw. 1...Base, 2...Main column, 3...Sub-column, 4...Elevating frame, 6...Saw frame,
7, 8... Saw wheel, 9... Band saw blade, 9a...
Line of cutting action, 10... Vertical guide groove, 11... Horizontal guide groove, 12, 13... Pin, 14... Rocking cylinder, W... Work material, A... Cutting curve.

Claims (1)

[Claims] 1 A saw frame equipped with a pair of left and right saw wheels for running a loop-shaped band saw blade is supported on an elevating frame that moves up and down against a vise that fixes a workpiece, and the saw frame is moved relative to the elevating frame. In a band saw machine in which the cutting locus of the band saw blade is a medium-height curve, the cutting path of the band saw blade is approximately on an extension line of the cutting action line of the band saw blade on either one of the lifting frame and the saw frame. A vertical guide groove extending in a substantially perpendicular direction, and a horizontal guide groove above the vertical guide groove that causes the band saw blade to have a cutting locus with a medium-height curve are provided; Pins to be slidably inserted are installed respectively, and an active telescopic means for connecting the saw frame and the elevating frame is disposed in a substantially tangential direction of the lateral guide groove, and the active telescopic means is driven. An oscillating band saw machine characterized in that the saw frame is configured to perform a swinging movement relative to the elevating frame that is regulated by the longitudinal guide groove and the lateral guide groove.