JP2002192420A - Band sawing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To move saw guides to a proper position between a cut starting position to a cut finishing position to minimize an unused part of a band saw corresponding to a work cutting length of the band saw. SOLUTION: A pair of saw guides 30, 31 are slidably supported on a saw frame 6 through a linear rail 26. The saw guides 30, 31 can be close to or separated from one another by a feed screw 27 which is a left and right inverse screw of equal pitches. Jaws 23a, 23b on a base 2 can be closed to or separated from one another by a feed screw 35 which is a left and right inverse screw of equal pitches. A work W is clamped by the pair of jaws 23a, 23b, an up-and- down cylinder 22 is driven to lower the saw frame 6, and the work W is cut. Opposite faces of the saw guides 30, 31 are recessed faces 24, and the saw guides 30, 31 are closest to one another during the whole cutting stroke from the cut starting position to the cut finishing position. The work W is stored between the recessed faces 24 of the saw guides 30, 31 when the cutting is finished.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention suppresses bending by automatically enlarging or reducing the interval between a pair of saw guides for holding a band saw so as to be able to travel freely in accordance with the cutting length of a work such as a round bar. The present invention relates to a band sawing machine.

[0002]

2. Description of the Related Art A band saw machine as shown in FIGS. 5 and 6 is conventionally known as a machine tool for cutting a work such as a large diameter round steel. This band sawing machine 1 is called a horizontal band sawing machine, and has a substantially rectangular base 2 which is long in the left-right direction.
A vice 3 composed of a fixed jaw 3a and a moving jaw 3b for fixing the work W thereon, and a lifting / lowering cylinder guided by a main column 4 and a sub-column 5 vertically erected vertically on the upper surface of the base 2. 13, a saw frame 6 which can be raised and lowered in a horizontal state, and a drive side saw wheel 7 and a driven side saw wheel 8 which are rotatably arranged on both left and right sides of the saw frame 6.
And a saw frame 6 between the saw wheels 7, 8
The fixed side saw guide 10 is fixed to the saw guide rail 9 at the right side in the figure, and the saw wheel 7, 8 is located between the saw wheels 7 and 8 and the saw guide rail 9 of the saw frame 6 is at the left side in the figure (FIG. And a movable side saw guide 11 slidably engaged and supported as shown in FIG.

The cutting of the work W by the band saw machine 1 is performed by rotating the driving side saw wheel 7 by a drive motor (not shown) and lowering the saw frame 6 while rotating the band saw 12.
At this time, the position of the moving-side saw guide 11 is adjusted in order to increase the distance between the saw guides 10, 11 to the diameter (maximum width) of the work W or more so that the saw guides 10, 11 do not interfere with the work W. And fix it.

[0004]

As described above, in the conventional band saw machine 1, the interval between the saw guides 10 and 11 is increased to be larger than the diameter (maximum width) of the work W, and the work W is cut in this state. Therefore, as shown in FIGS. 7 and 8, the play portion 12a of the band saw 12 is shortest at the intermediate cutting portion of the work W, but other portions, particularly the cutting start portion 15 (work W
In the vicinity of the upper end of the workpiece W and the cutting end portion 16 (near the lower end of the work W), the saw guides 10 and 11 hold the band saw 12 at a position far away from the cutting portion of the work W. For this reason, the play portion 12a of the band saw 12 between the saw guides 10, 11 and the work W becomes longer at the cutting start portion 15 and the cutting end portion 16 of the work W, and the band saw 12 is formed by the long play portion 12a. 9 (D), the cutting surface bends in the front-rear direction (left-right direction in FIG. 9) of the band saw machine 1 as shown in FIG.
Tends to occur.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to move a saw guide to an appropriate position so that a play portion of a band saw is minimized in accordance with a cutting length of the band saw. To make it happen.

[0006]

According to a first aspect of the present invention, there is provided a band sawing machine having a pair of left and right saw wheels on which an endless band saw is wound. A saw frame that is supported by the means so as to be able to move up and down, and a band saw that cuts a work W that is supported by the saw frame between the saw wheels and is fixed on a base by a vice that can be opened and closed. A pair of left and right saw guides, which are vertically twisted with respect to each other and held so as to be able to run freely, the pair of saw guides being slidably supported by the saw frame, and mutually facing surfaces of the saw guides. Is formed in a concave surface, and the work W can be accommodated between the concave surfaces of the saw guide in a state where the saw guides are brought closest to each other.

This makes it possible to bring the saw guide closest between the cutting start portion and the cutting end portion of the work W, and to shorten the play portion of the band saw in these portions where cutting and bending are particularly problematic to reduce cutting and bending. It can be suppressed as much as possible.

According to a second aspect of the present invention, in the band sawing machine, the distance between the saw clamping portions at the tips of the saw guides in a state where the saw guides are closest to each other is set to be equal to each other. It is characterized in that it corresponds to the cutting length of the work W between the cutting start part and the cutting end part of W.

Thus, the play portion of the band saw between the cutting start portion and the cutting end portion of the work W can be minimized, and the bending can be suppressed to a minimum.

According to a third aspect of the present invention, in the band sawing machine, the up-and-down driving means of the saw frame is provided with an encoder capable of detecting the up-and-down position of the saw frame.
The left and right moving means of the saw guide that slides along the saw frame is provided with an encoder capable of detecting the left and right position, and the saw holding portion of the saw guide is formed based on a signal from an encoder of the lifting drive means. The saw guide is controlled so as to follow the surface of the work W.

The elevation drive means with an encoder is particularly effective when the workpiece W has a regular cross-sectional shape, such as a round bar, and requires no special sensor for detecting the cutting length of the workpiece W. The cutting length of the work W can be calculated from the elevating position (cutting position), and based on the calculation result, the saw guide can be slidably controlled so that the saw holding portion follows the surface of the work W. In addition, it goes without saying that a sensor for detecting the elevation position of the saw frame may be separately provided instead of the encoder of the elevation drive means.

According to a fourth aspect of the present invention, in the band sawing machine, the pair of saw guides and / or the pair of jaws forming the vice are provided with a pair of jaw moving mechanisms. It is characterized in that a centering mechanism is provided in which the center positions between the jaws are constant.

As a centering mechanism, there is generally known a feed screw composed of right and left reverse screws with a center portion as a boundary, and the jaws of a saw guide and a vice are fixed at the mutual center position by such a feed screw. By approaching and separating from the workpiece W, the position adjustment of the saw guide and the jaw with respect to the work W can be made unnecessary or simplified.

Further, in the band sawing machine according to the present invention, as set forth in claim 5, the moving mechanism for the pair of jaws is provided with a centering mechanism for keeping the center position between the pair of jaws constant, and the jaw is provided. An encoder capable of detecting the mutual distance between the workpiece W is provided, and a cutting length at a cutting height position of the workpiece W is calculated based on signals from the jaw moving mechanism and an encoder of the lifting drive means. The distance between the guides is controlled so that the saw clamping portion follows the outer shape of the work W when the saw frame is moved up and down.

As described above, by providing an encoder capable of detecting the distance between the jaws, the width or outer diameter of the work W can be immediately determined only by clamping the work W, and this data is transmitted to the controller of the band sawing machine. By automatically taking in the work, the work of inputting the width or the outer diameter of the work W by the operator can be omitted, and even if the work W has a randomly different width or outer diameter, a quick cutting work can be performed. .

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. 1 and 2 show a band saw 21 according to the present invention, in which 2 is a base,
4 is a main column, 5 is a sub column, 6 is a saw frame, 7 is a driving side saw wheel, 8 is a driven side saw wheel, and 12 is an endless band saw. These are the same as the conventional band saw machine 1 of FIGS. The features of the band saw machine according to the present invention are that the opposing surfaces of the pair of saw guides 30 and 31 are concave surfaces 24, and the saw frame 6 is moved up and down by the elevating cylinder 22 with an encoder capable of detecting the elevating position. That is, the pair of saw guides 30 and 31 have an approaching / separating function and have an encoder capable of detecting the mutual distance, and an encoder capable of detecting the mutual distance of the pair of jaws 23a and 23b of the vise 23 is provided. When cutting a known work W having a regular cross section such as a round bar, the work W is clamped by the vise 23 and the outer diameter of the work W is detected based on a signal from the encoder. .

The following is a more detailed description including the above-mentioned features. The opposing surfaces of the pair of saw guides 30 and 31 are concave surfaces 24 as shown in FIG. This concave surface 24
More specifically, it is desirable that the concave surface 24 corresponds to the outer shape of the work W to be cut as shown in FIG. 4, but since the cross-sectional shape and dimensions of the work W are undefined, the band saw 12 Reaching the cutting end portion 16, the saw guide 30,
Of course, as long as the work W can be accommodated between the concave surfaces 24 when the 31 is brought closest, it is of course possible to appropriately change an arc-shaped concave surface or an L-shaped concave surface.

At the lower ends of the saw guides 30 and 31, FIG.
A groove 25 is formed as shown in FIG. 2A, and the trunk of the band saw 12 is inserted into the groove 25 so as to be able to run. The upper ends of the saw guides 30 and 31 are slidably engaged with two upper and lower horizontal linear rails 26 fixed to the front surface of the saw frame 6. On the other hand, a feed screw 27 is disposed on the upper surface of the saw frame 6 in parallel with the horizontal linear rail 26. One end of the feed screw 27 is connected and supported by a saw guide drive motor 28, and the other end is supported by a bearing 29. ing. Feed screw 27
Is a forward / reverse screw having the same pitch at the center of the feed screw. The uppermost ends of the saw guides 30 and 31 are screwed to the left and right sides of the feed screw 27, respectively.

The lifting cylinder 2 for raising and lowering the saw frame 6
Numeral 2 is disposed vertically inside the main column 4 as shown in FIG. The upper end of the rod 22a of the lifting cylinder 22 is connected to the saw frame 6, and the expansion and contraction of the lifting cylinder 22 causes the saw frame 6 to move up and down in a horizontal state while being guided by the main column 4 and the sub column 5. An encoder is attached to the elevating cylinder 22, and the encoder generates a pulse corresponding to the amount of expansion and contraction of the rod 22a. The number of pulses is counted by a first pulse counter built in a controller (not shown) of the band sawing machine 21, and based on the count value, the saw guide drive motor 28 is driven to rotate forward or reverse so as to move to a predetermined position. It has become. More specifically, when the work W is made of round steel, when the lifting cylinder 22 extends to the maximum and the saw frame 6 reaches the highest position, the first pulse counter is reset, and the saw guides 30 and 31 come closest to each other. The saw guide drive motor 28 is driven so that the band saw 12 starts to rotate, and the lifting / lowering cylinder 22 is shortened to start cutting the work W, and the saw frame 6 is lowered to the intermediate height position of the work W and the band saw is moved. Until the time when 12 cuts the diameter portion of the work W, the saw guide drive motor 28 is driven forward so as to maximize the interval between the saw guides 30 and 31 to the minimum necessary so as not to interfere with the work W. The saw guide drive motor 28 is operated so as to make the interval between the saw guides 30 and 31 as close as possible until the elevating cylinder 22 is further shortened and the saw frame 6 is lowered and the band saw 12 cuts the vicinity of the lower end of the work W. It is driven in reverse. As described above, the driving of the saw guide driving motor 28 is performed in conjunction with the expansion and contraction of the elevating cylinder 22, and the saw holding portion 32 continuously follows the outer shape of the work W with a slight gap.

The vise 23 comprises a pair of right and left jaws 23a and 23b slidably disposed on the upper surface of the base 2. The lower ends of these jaws 23a and 23b are
It is inserted into a slit (not shown) formed on the upper surface in the left-right direction. A jaw drive motor 34 is disposed on one side of the base 2 with its axis horizontal. One end of a feed screw 35 disposed horizontally below the slit of the base 2 is connected to the jaw drive motor 34. I have. The feed screw 35 is a forward / reverse screw having an equal pitch bordering on a central portion thereof.
The jaws 23a and 2a are provided on the left and right sides of the feed screw 35, respectively.
The lower end of 3b is screwed. Jaw drive motor 34
An encoder (not shown) is attached to the sensor so that the distance between the jaws 23a and 23b can be detected by the encoder.

The driving side saw wheel 7 of the band sawing machine 21 described above,
The lifting cylinder 22, the saw guide drive motor 28, and the jaw drive motor 34 are centrally controlled by the controller of the band saw machine 21. This controller has a built-in second counter for counting the pulses generated by the encoder of the jaw drive motor 34 in addition to the first counter for counting the pulses generated by the encoder of the lifting cylinder 22 described above. . And
The work W is clamped by the vise 23 and
When the cutting start switch is turned on, the lifting cylinder is shortened based on the detected value, and the saw guide drive motor 28 is driven by the saw guide drive motor 28 based on signals from the first and second counters. Each of the saw holding portions 32 of 30 and 31 is driven to rotate forward or reverse so as to follow the outer shape of the work W.

The band saw 21 is constructed as described above.
The cutting of, for example, a round bar as the work W using the band saw machine 21 is performed as follows. First, the work W is mounted on the base 2
Before placing on the top, turn on the operation switch of the vise 23,
The pair of jaws 23a and 23b are brought close to contact each other. Then, in this state, the second pulse counter for the jaw drive motor 34 is reset to the origin. Next, the work W is placed between the jaws 23a and 23b on the base 2 by separating the pair of jaws 23a and 23b, and the operation switch of the vise 23 is turned on again to operate the jaw drive motor 34. As a result, the feed screw 35 rotates, the pair of jaws 23a and 23b approach each other, and the work W is sandwiched between the jaws 23a and 23b from both sides and clamped at the centering position. The pulses generated by the encoder of the jaw drive motor 34 are counted by the second pulse counter, and the amount of rotation of the jaw drive motor 34 or the feed screw 35 from the origin is detected, and thus the pair of jaws 23a, 23b
Are detected.

Next, the drive side saw wheel 7 and the lift cylinder 2
When each of the operation switches 2 is turned on, the saw frame 6 is slowly lowered from the highest position while the band saw 12 is driven to rotate. At this time, the pair of saw guides 30 and 31 are in the closest approach state in advance. Pulses generated by the encoder of the lifting cylinder 22 as the saw frame 6 descends are counted by the first pulse counter, and the amount of shortening of the rod 22a from the most extended state of the lifting cylinder 22 is detected.
The height of the saw frame 6 from the upper surface or the saw guides 30, 3
The height of one saw holding portion 32 is detected. When the work W is a round steel, the width and the height of the work W are the same, so that the pair of jaws 23a and 23 detected by the second pulse counter are used.
The height from the upper surface of the base 2 to the uppermost end of the work W is determined from the mutual distance b or the width of the work W. Then, it is determined whether or not the band saw 12 has reached the uppermost end of the workpiece W, that is, the cutting start position, based on the detection values from the first and second pulse counters. While the cutting 12 advances from the cutting start position 15 to the intermediate height position (maximum cutting length position) of the workpiece W, the saw guide drive motor 28 operates continuously, and the forward rotation of the feed screw 27 causes the saw guides 30 and 31 to rotate. Move slowly in the direction away from each other. As a result, the saw clamping portions 32 of the saw guides 30 and 31 move so as to follow the upper half of the outer shape of the work W.

Next, after the band saw 12 reaches the intermediate height portion of the work W and continues to cut to the cutting end portion 16 of the work W, the saw guide drive motor 28 is continuously operated, and the reverse of the feed screw 27 is performed. Due to the rotation, the saw guides 30 and 31 move slowly in a direction approaching each other. As a result, the saw clamping portions 32 of the saw guides 30 and 31 move so as to follow the lower half of the outer shape of the work W.

As described above, while the band saw 12 advances from the cutting start portion 15 to the cutting end portion 16 of the work W, the pair of saw holding portions 32 expand and contract with each other corresponding to the cutting length of the band saw 12, and A band saw play portion between the holding portion 32 and the outer shape of the work W is made the shortest length. Thereby, the straightness of the band saw 12 that cuts into the work W is stabilized, and the cutting and bending are suppressed. When the cutting of the work W is completed, the saw frame 6
Is raised, and the saw guides 30 and 31 expand and contract so as to follow the outer shape of the work W by an operation reverse to that at the time of cutting. As described above, one embodiment of the present invention has been described. However, the present invention is not limited to the above embodiment, and various modifications are possible.
Although the centering mechanism is provided for the moving mechanism of a and 23b,
One of the jaws 23a or 23b may be fixed, and the other may be movable. In this case, since the center position of the work W changes depending on the size of the work W, a feed screw and a drive motor are required for each of the saw guides 30 and 31 to cope with the change.

[0026]

As described above, according to the present invention, since the mutually facing surfaces of the saw guide are formed as concave surfaces, the saw guide can be used not only from the cutting start portion to the intermediate portion but also from the intermediate portion to the cutting end portion of the work. The closest approach can be achieved, and the cutting and bending can be suppressed in all the cutting processes from the cutting start portion to the cutting end portion.

Further, by attaching an encoder to the lifting cylinder for raising and lowering the saw frame, the cutting length of the workpiece can be detected based on the cutting advance position of the band saw on the workpiece, and hence the sectional shape of the workpiece. The spacing can be automatically determined to minimize the play of the band saw.

Further, by providing the centering mechanism in the moving mechanism of the pair of jaws forming the pair of saw guides and the vise, the position adjustment of the saw guide and the jaws with respect to the work W can be made unnecessary or simplified.

Further, the outer diameter of the work is detected based on a signal from an encoder capable of detecting the distance between the pair of jaws, and the distance between the saw guides is controlled based on the detection result. The width or outer diameter of the work can be immediately determined just by clamping, and automatically inputting this data into the controller of the band saw machine eliminates the need for the operator to input the work width or outer diameter.

[Brief description of the drawings]

FIG. 1 is a front view of a band saw machine according to the present invention.

FIG. 2 is a plan view of the band saw machine according to the present invention.

FIG. 3 is an enlarged front view showing a state in which the saw guide approaches and separates from each other.

FIG. 4 is an enlarged front view of the saw guide at the end of cutting.

FIG. 5 is a front view of a conventional band saw machine.

FIG. 6 is a plan view of a conventional band saw machine.

FIG. 7 is an enlarged front view showing a state in which a saw guide approaches and separates in a conventional band saw machine.

FIG. 8 is an enlarged front view of a saw guide at the end of cutting of a conventional band saw machine.

9A is a side view of a saw guide of the band saw machine according to the present invention, FIG. 9B is a side view of a cutting portion of a work by the band saw machine,
(C) is a side view of a saw guide of a conventional band saw machine, and (D) is a side view of a cutting portion of a work by the band saw machine.

[Explanation of symbols]

 2 Base 4 Main Column 5 Sub Column 6 Saw Frame 7 Driving Saw Wheel 8 Driven Saw Wheel 12 Band Saw 21 Band Saw Machine 22 Elevating Cylinder 23 Vice 24 Concave Surface 25 Groove 26 Horizontal Linear Rail 27 Feed Screw 28 Saw Guide Drive Motor 29 Bearing 30, 31 Saw guide 32 Saw holding part 34 Jaw drive motor 35 Feed screw W Work

Claims (5)

[Claims] 1. A saw frame having a pair of left and right saw wheels on which an endless band saw is stretched and supported by a lifting drive means so as to be able to move up and down, and supported by the saw frame between the saw wheels. A band saw having a pair of left and right saw guides for vertically twisting and raising a band saw on a side for cutting a work fixed on a table with a vice that can be opened and closed freely, with respect to the work; A guide is slidably supported on the saw frame, and the opposing surfaces of the saw guide are formed as concave surfaces, and the workpiece is placed between the concave surfaces of the saw guide in a state where the saw guides are closest to each other. A band sawing machine characterized in that it can be accommodated. 2. The mutual interval between the saw clamping portions at the tip of the saw guide when the saw guides are brought closest to each other corresponds to the cutting length of the work between the cutting start portion and the cutting end portion of the work. 2. A band saw machine according to claim 1, wherein said band saw machine is operated. 3. The saw frame raising / lowering drive means is provided with an encoder capable of detecting the elevation position of the saw frame, and the saw guide left / right moving means that slides along the saw frame detects the left / right position. And a saw encoder which controls the saw guide based on a signal from the encoder of the elevation drive means so that the saw holding portion of the saw guide follows the surface of the work. Item 1. A band sawing machine according to item 1 or 2. 4. A mechanism for moving the pair of jaws constituting the pair of saw guides and / or the vise, wherein a centering mechanism is provided so that a center position between the pair of saw guides and the pair of jaws is constant. The band saw machine according to any one of claims 1 to 3, characterized in that: 5. A mechanism for moving the pair of jaws, wherein a centering mechanism for keeping a center position between the pair of jaws constant is provided, and an encoder capable of detecting a distance between the pair of jaws is provided. A cutting length at a cutting height position of the workpiece is calculated based on a signal from an encoder of a mechanism and a lifting drive unit, and the distance between the saw guides based on the calculation result is used by the saw holding unit to raise and lower the saw frame. The band sawing machine according to any one of claims 1 to 3, wherein the band saw is controlled so as to follow the outer shape of the work.