JPH04126201A - Automatic feed-speed changing apparatus for lip saw - Google Patents

Abstract

PURPOSE:To enable the feed-speed of a work material to be adjusted properly in accordance with the thickness of the work material by providing material forwarding motor control means equipped with a computing unit by which a value obtained by multiplying the speed reduction coefficient selected on the basis of the height information of a tread pressure frame transmitted from position detecting means and standard command voltage together is allowed to be command voltage to a non-stage transmission. CONSTITUTION:Each position detecting at eight places is made possible by detecting switches S1-S2 and, by the ON-position of the detecting switch S, the height of a tread pressure frame 18 is detected. The ON-operational output from position detecting means is sent to a selecting circuit 33 and the output of the selecting circuit 33 is sent to the coefficient designating part 35 of a material forwarding motor control means C. Onto the coefficient designating part 35, the speed reduction coefficient f1 is set in corresponding to the height of each detecting switch S1-S8 and, in a computing unit 36, the speed reduction coefficient f1 and the standard command voltage V0 inputted from a voltage generating device 37 are multiplied together, so that command voltage (=V0Xf1) is outputted therefrom. The command voltage V is inputted into a non-stage transmission 12 and the frequency proportioned to the voltage V is selected, and a material feeding motor M1 is driven in accordance with the frequency.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rip saw for cutting workpieces fed by feeder caterpillars with a circular saw, and to an automatic feed speed converter therefor.

[Prior Art] A material feeding caterpillar that travels on the upper surface of a material feeding frame, a circular saw that is supported by an upper frame on the material feeding frame and rotates on the material feeding caterpillar, and a material feeding material before and after the circular saw. Various types of rip saws have been proposed that include a tread frame that supports a corresponding tread roller on caterpillars and is movable up and down, and a material feeding motor that drives the material feeding caterpillar. However, as the thickness of the workpiece sent to the rip saw increases, the load placed on the circular saw increases.

For this reason, if the workpiece is fed at a constant speed regardless of its thickness, if the workpiece is thick, excessive load will cause
It is not possible to obtain a good cut surface, leading to metal fatigue of the circular saw and causing the blade to chip.

Therefore, as disclosed in Japanese Utility Model Publication No. 57-26727, a rack is attached to the treading frame, and a pinion that rotates as the rack moves up and down is attached to the fixed member on the upper frame or the material feeding frame. A configuration has been proposed in which the amount of rotation is transmitted to a gear shift adjustment shaft of a transmission via an endless chain or the like. This attempts to control the feed rate in inverse proportion to the thickness of the workpiece.

[Problems to be Solved by the Invention] In this configuration, the continuously variable transmission is controlled by rotating the speed adjustment shaft by running the endless chain as the pedal frame moves, and the structure is This method uses mechanical means, which has the disadvantage that the overall structure becomes complicated and the device becomes large-scale. Further, the adjustment rate is determined by the transmission gear ratio, and such gear replacement is not normally performed, so that it is not possible to arbitrarily adjust the amount of deceleration of the workpiece corresponding to the position of the tread pressure frame. Furthermore, the relationship between the pedal pressure frame and the amount of deceleration can only be roughly determined. For this reason, the method was not necessarily optimal for the material of the workpiece.

An object of the present invention is to provide an automatic feed rate converter that can appropriately adjust the feed rate of a workpiece in accordance with the thickness of the workpiece without causing such problems.

[Means for Solving the Problems] The present invention provides a material feeding caterpillar that runs on the upper surface of a material feeding frame, a circular saw that is supported by an upper frame on the material feeding frame and rotates on the material feeding caterpillar, In the rip saw, which is equipped with a tread pressure frame that supports a tread pressure roller corresponding to the feeding material caterpillar at the front and rear of the circular saw and can be raised and lowered, a continuously variable transmission is provided which generates a rotation speed proportional to the voltage by inputting a command voltage. a material feeding motor that drives the material feeding caterpillar, a position detection means that detects the height of the treading frame, and a deceleration coefficient that corresponds to the height of the treadling frame and is approximately inversely proportional to the height. a calculation unit that selects a deceleration coefficient based on preset height information of the pedal pressure frame from the position detection means, and sets a value obtained by multiplying the selected deceleration coefficient and a reference command voltage as a command voltage to the continuously variable transmission; The present invention is characterized by comprising a material feeding motor control means.

Here, "Habo inversely proportional" means a relationship in which the deceleration coefficient decreases in response to the height of the pedal pressure frame, and it means that it includes not only a linear function-like inverse proportionality but also a complex function-like inverse proportional tendency. It is.

With this configuration, the load value applied to the circular saw is detected, and if the load value is larger than a predetermined load threshold, a subtraction coefficient that is inversely proportional to the load value is set to a predetermined fixed reference voltage. The value obtained by multiplying is the reference command voltage,
A reference command voltage generator may be further provided that outputs a fixed reference voltage as the reference command voltage to the material feeding motor control means when the load value applied to the circular saw is less than or equal to the load threshold value.

[Operation] The tread frame is lowered and moved to a position where the tread roller presses the workpiece with an appropriate pressure. The height of the tread pressure frame at this time is read by the position detection means.

Then, the material feeding motor control means selects a deceleration coefficient corresponding to this height information, multiplies the deceleration coefficient with the reference command voltage, and determines the command voltage to the continuously variable transmission.

Then, the material feeding motor rotates at a rotational speed lower than the maximum rotational speed determined by the command voltage.

Since the above-mentioned deceleration coefficient is set in substantially inverse proportion to the height of the tread pressure frame, the thicker the workpiece, the smaller the coefficient becomes, and the command voltage to the material feed motor becomes smaller. Therefore, as the thickness of the workpiece increases, the rotational speed of the material feed motor decreases, and the speed at which the workpiece is fed by the material feed caterpillar decreases, so that the circular saw is not subjected to excessive load. will be cut off.

On the other hand, although the deceleration coefficient is experimentally set to the best value in advance depending on the thickness of the workpiece, in reality it may not be the best value due to changes in the material of the workpiece. ,
Overload may be applied due to knots, etc. Therefore, this problem is solved by providing a reference command voltage generator as described above.

In other words, the load on the circular saw is detected as, for example, a current value, and this load value is set to a predetermined load threshold (
If it is larger than this value, a subtraction coefficient that is inversely proportional to the load value is calculated, and the subtraction coefficient is multiplied by the fixed reference voltage that determines the maximum rotational speed of the material feeding motor. This is set as a reference command voltage, and the reference command voltage is used as the material feeding motor control means. Then, as described above, this material feeding motor control means multiplies the standard command voltage with a deceleration coefficient that is inversely proportional to the height of the tread pressure frame, determines the speed of the material feeding motor, and causes the workpiece to travel at that speed. . Since this speed has been reduced in response to the above-mentioned overload, the load value on the circular saw is accordingly reduced, and if this is still greater than the load threshold, it is further reduced by the steps described above. and becomes below the load threshold value (current value). As a result, the subtraction coefficient becomes 1, and the fixed reference voltage and the reference command voltage become equal, and the material feeding speed is adjusted by the material feeding motor control means only by the deceleration coefficient corresponding to the thickness of the material to be processed. becomes.

With this configuration, the position of the tread pressure frame is detected by the position detection means, and the speed of the workpiece is adjusted using a deceleration coefficient or a subtraction coefficient. It can be the traveling speed.

[Example] An embodiment of the invention will be described with reference to FIG. 1.2.

In the figure, reference numeral 1 denotes a material feeding frame, on which a material feeding table 2 is provided, and idling wheels 4 and drive wheels 5, which are pivotally supported on the front and rear sides of the material feeding frame 1, are mounted front and rear in the center. A material feeding caterpillar 6 consisting of a chain of guide plates 7 connected by a chain shaft on the back side is hung, and the upper running part of the material feeding caterpillar 6 is made to slightly protrude above the material feeding table 2. There is. The lower surface of the upper running part is supported by a support plate 9 with a concave cross section, and the idle wheels 4 and drive wheels 5, which have shafts 10 supported on the material feeding frame 1 side, pass through the support plate 9 to feed the material. It engages with Caterpillar 6.

Ml is a material feeding motor equipped with a continuously variable transmission 12, and an endless chain 14 is stretched between its variable speed output shaft 13 and a silver ring 11 fixed to the shaft 10 of the driving wheel 5.

An upper frame 3 is supported on the side of the material feeding frame 1,
Inside the upper frame 3, a shaft 16 with a circle #A15 whose lower top edge rotates within the range of the material feeding caterpillar 6, and a drive motor M2 for driving the shaft 16 are installed, and the drive motor M2.
The shaft 16 and the like can be adjusted up and down by rotating the handle shaft 17.

A tread pressure frame 19 is disposed on the side surface of the upper frame 3 via a vertical sliding guide 18 provided on the side surface, and the vertical position of the tread pressure frame 19 can be adjusted by a control shaft 22 rotated by a handle 21. It is said that This position adjustment can also be performed by motor drive. On the tread frame 19, tread pressure rollers 23, 24, and 25, which project slightly downward from the frame, are supported by cushion springs 26 at the front, rear, and both sides of the circular saw 15. Treading frame 1
9 also includes a reverse running prevention claw 27 and a rebound prevention device 28.
, a chip discharge port 29, etc. are provided.

A rip saw having such a configuration is well known, and an embodiment in which the present invention is applied thereto will be described in detail.

In FIGS. 2 and 3, non-contact detection switches 5 (81 to S8) are arranged in rows on the left and right sides of the upper frame 3 in the vertical direction. Detected ends 31.31 made of horizontal plates are projected to both sides of the bracket 32 supported by the tread pressure frame 19, and both ends thereof cover the detection portion of the detection switch S as it moves up and down, and the detection switch S constitutes a position detecting means 30 that detects the height of the tread pressure frame 19 by detecting the tip of the detected end 31.31.

As the detection switch S, a contact type limit switch or the like may be used, as well as a magnetic field type proximity switch that detects an object by disturbance of a magnetic field, a photoelectric type switch, or the like. The respective detection switches S are shifted in position in the vertical direction, and the left and right detection switches S are positioned midway between the left and right. That is, in the figure, eight positions can be detected by the detection switches 81 to S8. Since the detected end 31.31 indicates the height of the pedal frame 19, the height of the pedal frame 19 is detected by the ON position of the detection switch S.

In this configuration, one of the detection switches S is always turned on by the detected ends 31 and 31. If the detection target 31.31 is located between adjacent detection switches S, any detection switch S
This is because if there is an off state, the deceleration coefficient f1, which will be described later, will not be set, resulting in excessive speed.

In order to ensure that one of the detection switches S always detects the short end to be tested 31.31, it is necessary to turn on the two detection switches S at the same time in the intermediate position. . If two detection switches S are turned on at the same time, it is necessary to process information by always validating only the detection switch S in the upper position.

Therefore, the ON operation output from the position detection means 30 is sent to the -H1 selection circuit 33. This selection circuit 33 is connected to each of the detection switches S, ~S, and processes the signal when the detection switch S is turned on, and when a single detection switch S is turned on, its signal output is divided into two or When more detection switches S are turned on, an output is given to give priority to the higher order detection switch S. For example, the detection switch Sl+
82 are on, the upper detection switch S2 is enabled.

The output from this sorting circuit 33 is sent to a coefficient specifying section 35 of the material feeding motor control means C, as shown in FIG. The coefficient specifying section 35 is provided with each detection switch S, -
A deceleration coefficient f is set corresponding to the height of S.

This deceleration coefficient f is, for example, 0.9 for the detection switch S1.
, detection switch S2 is 0.8, detection switch Sj is 0,
7...The detection switch S is set to become smaller as it goes higher, such as 0 and 2. Then, the calculation section 36
This selected deceleration coefficient f.

and the reference command voltage ■ inputted from the voltage generator 37. are multiplied, and a command voltage V ("va For example, when the reference command voltage V0 is 10 volts DC, when the detection switch S2 is turned on, the continuously variable transmission 12 receives 8 volts (=10X0. 8) is applied.In this continuously variable transmission 12, for example, if a frequency of 60 Hz is selected for a command voltage of 10 volts, a frequency of 48 Hz (60 x 8 / 10) is applied. The variable speed output shaft 13 of the material feeding motor M1 rotates at a speed corresponding to the following.

In this way, the height position of the tread pressure frame 19, that is, the thickness of the workpiece W is detected by turning on any of the detection switches 81 to Ss, and as a result, the larger the thickness, the smaller the deceleration coefficient f1 is selected. , small command voltage■
occurs, and the material feed motor M rotates at a rotation speed that is inversely proportional to the thickness of the workpiece W, and the material feed caterpillar 6 travels via the drive wheel 5 to achieve the optimum running speed for the thickness of the workpiece W. The speed will be applied to the workpiece W.

By the way, the deceleration coefficient f1 is predetermined in accordance with the thickness of the workpiece W, and in actual machining conditions, there are various materials for the workpiece W that can be applied, and even if the same material is used, instantaneous deceleration may occur. A large load may occur. Therefore, a configuration may be adopted in which the reference command voltage generating device F shown in FIG. 5 is provided and the command voltage (2) is successively corrected depending on the load applied to the drive motor M2.

The load value I applied to the drive motor M2 can be detected as a current value to the drive motor M8. This load value I (current value) is converted into a digital signal by an A/D converter and is converted into a digital signal by a comparison section 4 of the reference command voltage generator F.
The load threshold value I0 inputted to 0 and set in advance by a threshold value setting unit 41 such as a switch panel is compared with the load value value, and the comparison result is sent to the calculation unit 42. This calculation section 4
2, a fixed reference voltage from the fixed voltage generator 43;
is input.

And load value engineering≦1. In the case of {circle around (2)}, =Vo is set and the sheet is sent as is to the material feeding motor control means C described above. That is, the maximum rotational speed of the material feeding motor M1 is determined by this fixed reference voltage V8, the material feeding motor M is always rotated by a command voltage 2 below this value, and the upper limit of the speed of the workpiece W is determined thereby. Become. Furthermore, the maximum rotational speed corresponding to the thickness of the workpiece W is determined by the fixed reference voltage V x deceleration coefficient r1. Therefore, in the configuration shown in FIG. 5 which includes the reference command voltage generator F, at the initial stage of material feeding, the maximum speed corresponding to the thickness of the workpiece W is commanded by the material feeding motor control means C. That will happen.

Therefore, this fixed reference voltage v6 is set to the fixed voltage generator 43.
By adjusting with , it is possible to perform processing without difficulty.

On the other hand, if the load value I>1. In the case of 1. /I is the subtraction coefficient f2, and V*xft=V. As, fixed reference voltage ■1
A reference command voltage V0 smaller than the reference command voltage V0 is generated. Therefore, the command voltage ■ generated via the material feeding motor control means C is v*
Xf, Xf, and as the load on the drive motor M2 increases, the rotational speed of the variable speed output shaft 13 of the material feeding motor M1 decreases, the material feeding speed of the workpiece W decreases, and the load on the drive motor M2 increases. is alleviated. Therefore, the material feeding motor M is successively optimally adjusted in accordance with the actual processing conditions.

With each of the above-mentioned configurations, the workpiece W travels at an optimal speed that does not impose an excessive load on the circular saw 15.
Cutting is performed well, the cut surface becomes beautiful, and the tooth loss of the circular saw 15 is reduced.

In the above configuration, instead of the position detection means 30 using the detection switch S, the control shaft 22, etc., the tread pressure frame 1
A slit plate is installed on the axis of the lifting drive system of No. 9 by means such as detecting the passing speed of the slit with an encoder.
The amount of elevation of the tread pressure frame 19 is detected, and thereby its height position can be detected. With the position detection means having such a configuration, the height position of the tread pressure frame 19 can be detected in a stepless manner, so that fine material feeding speed adjustment can be performed.

Further, the material feeding motor control means C and the reference command voltage generation device F can be integrally configured by using a central control device CPU.

Furthermore, the value of the deceleration coefficient f1 can be arbitrarily adjusted, and furthermore, it may be a complex function of the relationship between the height of the pedal pressure frame 19 and the deceleration coefficient f+.

For the subtraction coefficient f8, not only I o / I,
Various functions can be applied that take smaller values as the negative becomes larger.

[Effects of the Invention] As described above, in the present invention, the thickness of the workpiece W is detected by the position detection means 30, and the material feeding motor control means C uses information from the position detection means 30 and a predetermined deceleration coefficient. f
1, the traveling speed of the workpiece W is specified, so by selecting the deceleration coefficient f, the relationship between the tread pressure frame and the amount of deceleration can be arbitrarily selected, corresponding to the thickness of the workpiece W. The appropriate speed can be easily achieved.

In addition, when the reference command voltage generator F is provided in this configuration, the material feeding speed can be adjusted depending on the load applied to the drive motor M2, and machining that matches the actual machining conditions becomes possible.
Even when a sudden load occurs, the material feeding speed can be adjusted without difficulty, and cutting can be performed safely.

Furthermore, since each component commands the material feeding speed based on electrical signal processing, unlike adjusting the material feeding speed by mechanical means, there is no need to complicate or enlarge the device. It has excellent effects such as

[Brief explanation of the drawing]

The accompanying drawings show an embodiment of the present invention, and FIG. 1 is a side view, FIG. 2 is a partially cutaway rear view, FIG. 3 is an enlarged rear view of the main part showing the position detection means 30, and FIG. 4.5. is a block diagram. 3...Upper frame 5...Drive wheel 6...-Material feed caterpillar 12...Continuously variable transmission 15...Circular saw 19...Tread pressure frame 22...Control shaft 30...Position Detection means 31...Detected end 33...Selection circuit 35...Coefficient designation section 36...Calculation section 42...Calculation section fl...Deceleration coefficient f3...Subtraction coefficient S, S, ~S...Detection switch C...Material feeding motor control means F...Reference command voltage generator Ml...Material feeding motor M3...Drive motor

Claims (1)

[Claims] 1) A material feeding caterpillar that runs on the upper surface of the material feeding frame;
A circular saw is supported by an upper frame on the material feeding frame and rotates on the material feeding caterpillar, and a treading frame that can be raised and lowered supports a corresponding treadling roller on the material feeding caterpillar before and after the circular saw. A rip saw equipped with: a material feed motor that drives the material feed caterpillar and is equipped with a continuously variable transmission that generates a rotation speed proportional to the voltage upon input of a command voltage; and a position that detects the height of the tread pressure frame. A deceleration coefficient that is approximately inversely proportional to the detection means and the height of the tread pressure frame is set in advance, and the deceleration coefficient is selected based on the height information of the tread pressure frame from the position detection means, and the selected deceleration is performed. 1. An automatic feeding speed converter for a rip saw, comprising: a material feed motor control means comprising a calculation unit that sets a value obtained by multiplying a coefficient and a reference command voltage as a command voltage to a continuously variable transmission. 2) A feed caterpillar that runs on the top surface of the feed frame,
A circular saw is supported by an upper frame on the material feeding frame and rotates on the material feeding caterpillar, and a treading frame that can be raised and lowered supports a corresponding treadling roller on the material feeding caterpillar before and after the circular saw. A rip saw equipped with: a material feed motor that drives the material feed caterpillar and is equipped with a continuously variable transmission that generates a rotation speed proportional to the voltage upon input of a command voltage; and a position that detects the height of the tread pressure frame. A deceleration coefficient that is approximately inversely proportional to the detection means and the height of the tread pressure frame is set in advance, and the deceleration coefficient is selected based on the height information of the tread pressure frame from the position detection means, and the selected deceleration is performed. It detects the load value applied to the material feeding motor control means and the circular saw, and includes a calculation unit that sets the value obtained by multiplying the coefficient and the reference command voltage as the command voltage to the continuously variable transmission. , when the load value is large, a value obtained by multiplying a predetermined fixed reference voltage by a subtraction coefficient that is inversely proportional to the load value is set as the reference command voltage, and the load value applied to the circular saw is less than or equal to the load threshold value. 1. An automatic rip saw feed rate automatic converter, comprising a reference command voltage generator for outputting a fixed reference voltage as the reference command voltage to a material feeding motor control means.