JP2736140B2 - Frameless casting line - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a frameless casting line, and more particularly, to a frameless casting line capable of taking out a good casting.

[Prior Art] In a conventional frameless casting line, a sand molding machine, a pouring machine, a casting removal device, a sand recovery machine, and the like are arranged along a conveyor device for sand mold conveyance operated at intervals. The working environment is not good from the viewpoint of thermal and dust, and therefore, in recent years, automation of the work is expected.

2. Description of the Related Art Various types of casting removal devices for removing a casting from a sand mold are conventionally known.

Currently used casting unloaders have a drum cooler located at the end of the conveyor device. When a sand mold is put into this rotating drum cooler, the sand mold is separated into casting and sand. In addition, a casting remover which separates a casting from sand by dropping a sand mold on a vibrating sieve provided at the end of the conveyor device is also in practical use.

Further, the apparatus disclosed in Japanese Utility Model Laid-Open Publication No. 63-6146, 163260, 170066, 252666 has a casting take-out device arranged facing the end of the conveyor device, and the casting take-out device is a sand mold portion below the casting. And a pressing arm pierced into a sand mold portion above the casting. At the time of casting removal, after piercing each arm into the sand, both arms are relatively moved in a direction approaching each other to grip the casting vertically, and then both arms are turned or linearly moved in a horizontal plane. To remove the casting.

[Problems to be Solved by the Invention] However, in a casting removal device using a drum cooler or a vibrating sieve, the posture and position of the casting to be removed become insufficient, and the next handling of the casting (for example, placing on a casting conveyor) Operation) could not be automated and had to be performed manually. As a result, the operator has been burdened with a great amount of labor in a poor environment.

The casting removal device disclosed in each of the above-mentioned publications,
It is intended to eliminate the drawbacks of the casting removal device and remove the casting in a fixed posture, but has the following problems.

The first problem is that the sand mold stationary position varies with the interval operation of the conveyor device. That is, the individual sand molds constituting the frameless sand mold row are compressed in the conveyance direction by the impact force at the time of starting and stopping during conveyance. Also, the single travel distance of the conveyor device is not strictly constant, and as a result, the stationary position of the sand mold that has reached below the casting removal device varies. If the rest position of each sand mold under the casting removal device fluctuates, even if the extraction arm is always pierced by a certain depth into the sand mold, the relative position in the transport direction between the extraction arm and the casting will be undefined, and the subsequent handling will be difficult. Disturbance occurs. For example, when placing the extracted casting on a casting conveyor, it is difficult to place the casting without always holding the casting at a fixed position (generally, the tip) of the extraction arm. Further, the casting may be hooked incompletely on the extraction arm in the sand mold, and in this case, the extraction of the casting also fails.

The second problem is that, at the boundary between the individual sand molds constituting the frameless sand mold row, an opening, a shift, a collapse, etc. may occur as shown in FIG. And the extraction arm may fail or the extraction arm may damage the casting.

A third problem is that the casting removal device is configured to grip the casting (particularly its product part) with a large gripping force in the vertical direction and to remove the casting from the sand mold, and the removal arm may damage the casting. That is. If the casting surface to be gripped is not flat in the horizontal direction, or if the area of the casting surface to be gripped is insufficient, the probability increases. Furthermore, when manufacturing various types of castings with different sand molds on the same frameless casting line, it is not easy to grip each casting having a different shape.

If the position of the casting extraction portion (casting extraction position) can be determined well, the casting extraction device can be guided to the casting extraction position, so that the above problem can be solved. However, as described above, the casting removal position greatly fluctuates in the transport direction, so that the determination is not easy.

Therefore, the present inventor has noticed that since the casting extraction part is formed integrally with the gate, the casting extraction position can be accurately estimated by determining the position of the gate exposed in the sand mold in the transport direction.

Accordingly, the present invention has been made in view of such a problem, and it is an object of the present invention to provide a frameless casting line capable of accurately detecting a position at which a casting is extracted and enabling good and good casting to be extracted. Should be an issue to be addressed.

[Means for Solving the Problems] A frameless casting line according to a first configuration of the present invention intermittently conveys a frameless sand mold row composed of a plurality of sand molds connected in a row in a traveling direction and each having a gate. A casting extraction device having a withdrawal arm for extracting a casting from the sand mold and disposed above the end of the conveyor device; anda state of the upper surface of the sand mold disposed above the end of the conveyor device. A sand mold upper surface sensor to be detected, a sprue position judging means for processing an output signal of the sand mold upper surface sensor to judge the position of the sprue in the conveying direction, and extracting the casting extracting device based on the discriminated position of the sprue. A casting withdrawing position determining means for determining a position, wherein the casting withdrawing device is configured to connect the extracting arm with the gate and a casting (product part) based on the withdrawing position. Is characterized in that the casting is engaged with the runner section is intended to withdraw upwardly swingable state connecting. For example,
The frameless casting line of the present invention has an extraction part position determining means for determining a position of an extraction part of a casting formed integrally with the gate based on the determined gate position.

For example, the sand-type upper surface sensor can be of a type that magnetically detects the gate using a ferromagnetic material such as cast iron or molten steel. As the sand mold upper surface sensor, an optical sensor or a color sensor that detects light and darkness or color at one point of the sand mold upper surface, a radiation thermometer or an infrared sensor that detects the temperature of one point of the sand mold upper surface in a non-contact manner can be used.

In addition, a contact sensor that detects a gate by contacting the upper surface of the sand mold, or a line image sensor that captures an image of the upper surface of the sand mold in the transport direction can also be employed.

A frameless casting line according to the second configuration of the present invention is a conveyor device that intermittently conveys a frameless sand mold row composed of a plurality of sand molds connected in a line in the traveling direction and each having a sprue, and withdrawing a casting from the sand mold. A casting extraction device having an arm and disposed above a distal end of the conveyor device; a sand die upper surface sensor disposed above the distal end of the conveyor device and detecting a state of the upper surface of the sand die; Gate position determination means for processing the output signal of the upper surface sensor to determine the position of the gate in the transport direction, and casting removal position determination means for determining the removal position of the casting removal device based on the determined position of the gate. Wherein the sand mold upper surface sensor magnetically detects the gate.

Here, the term “magnetically detected” includes, for example, a case in which a cast iron product is detected magnetostatically, and a case in which, for example, an aluminum product is detected by an eddy current change.

[Operation] In the frameless casting line of the present invention, the conveyor device intermittently conveys the frameless sand mold row. The top of the sand mold of a frameless sand mold row consisting of a plurality of sand molds connected in a line in the traveling direction is provided with a gate regularly (generally at regular intervals), and the sand top sensor is the state of the top of the sand mold including the gate Is detected in the transport direction.

The gate position determination means processes the measured sand mold upper surface data to determine the position of the gate in the transport direction.

The casting removal position determining means specifies a removal position of the casting removal device based on the determined gate position.

Example (Example 1) Hereinafter, an example of the present invention will be described with reference to the drawings.

The frameless casting line includes a conveyor device 1, a conveyor moving distance detecting means 8, a low-pass filter 6, an A / D
It comprises a converter 7, a casting removal device 2, a sand mold upper surface temperature measurement device 3, and a microcomputer device 4 which also serves as a gate position discriminating means and a drawing arm driving means (see FIG. 1).

The conveyor device 1 is composed of a normal belt conveyor,
1, 7, and 8 illustrate the distal end.
The conveyor apparatus 1 is operated in the interval operation, the operation time is set to 2.2 seconds, the operation suspension period is set to 8.8 seconds, and during this operation suspension period, the casting is extracted and the gate center position is detected. Then, the conveyor device 1 advances the frameless sand mold row 5 by a distance equal to the normal transport direction dimension Lo of one sand mold 51 during one operation time. On the upstream side of the conveyor device 1, a frameless sand molding machine and a pouring machine (not shown)
At the end of the conveyor device 1, a casting extracting device 2 and a sand mold upper surface temperature measuring device 3 are disposed at a distance of about 50 m from the pouring machine for pouring and cooling.
Is provided with a sand collecting device 8 having a built-in sand collecting conveyor. On the conveyor device 1, a frameless sand mold row 5 formed by connecting about 200 sand molds 51 in a row is placed, and a boundary 52 between two adjacent sand molds 51 is used for casting products. The cavity 53 is formed, and a substantially rectangular gate 54 communicating with the cavity 53 is provided on the upper surface of the boundary portion 52 (see FIG. 1). Further, in the middle of a runner 55 from the sprue 54 to the cavity 53, a plan part 56 extending in the horizontal direction perpendicular to the conveying direction is formed, and the molten metal poured from the spout 54 is cooled and solidified to form a total of four parts. A casting (product part) A made of cast iron is cast, and a casting is also formed on the gate 54, the runner 55, and the plan portion 56. The runner 55 and the planner 56 constitute a runner in the present invention. Therefore, in the following description, the gate 54,
The runner 55 and the planner 56 mean a casting therein. Each sand mold
51 is about 28 cm in the normal transport direction, and one side of the gate 54 is about
Initially formed at 8 cm, and the scheme 56 constitutes the withdrawal of the casting.

The conveyor moving distance detecting means 8 is connected to a rotating shaft of a roller (not shown) of the conveyor device 1 immediately below the sand mold upper surface temperature measuring device 3 and outputs the rotation angle to the microcomputer device 4 as an angle signal Vz. Consists of a rotary encoder. Due to the weight of the frameless sand mold row 5, slippage between the roller and the belt (not shown) of the conveyor device 1 can be almost ignored, and if the rotation angle of the roller is detected, the conveyor device 1 You can see the moving distance of

The casting removal device 2 is movably supported by a rail 20 disposed above the end of the conveyor device 1 and has a structure of self-running on the rail 20 (see FIGS. 7 and 8). . The rail 20 has a leading end extending above a central portion in the left-right direction of the conveyor device 1, a central portion of the rail 20 curves upward in the horizontal plane in the drawing, and a terminal end of the rail 20 is substantially perpendicular to the transport direction. And it is close to a hanger conveyor (not shown). A pair of extraction arms 22 and 23 project downward from the lower surface of the casting extraction device 2.
Reference numeral 23 faces the extending direction of the rail 20, and the relative distance is variable by a hydraulic cylinder (not shown) built in the casting extracting device 2. The arms 22 and 23 are alternately arranged two by two, and a protrusion for swingably mounting the plan portion 56 is formed at a tip end thereof. The current position of the casting removal device 2 is constantly detected using an encoder (not shown) and is input to the microcomputer device 3. The casting extracted by the casting extracting device 2 swings by its own weight with the arms 22 and 23 as fulcrums and assumes a constant posture. After that, the casting extracting device 2 passes the extracted casting to a robot (not shown), and the robot receives the casting. The casting is hung on a hanger conveyor (not shown). Then, the casting removal device 2 that transfers the casting to the robot
Automatically returns to its reference position x2, and thereafter, is guided to the optimum withdrawal position by the microcomputer device 4.

The sand mold upper surface temperature measuring device (sand mold upper surface sensor in the present invention) 3 has a built-in radiation thermometer fixed above the end of the conveyor device 1. The radiation thermometer section is disposed downward above the central portion in the left-right direction of the conveyor device 1 and detects infrared rays emitted from a point immediately below the upper surface of the sand mold of the frameless sand mold row 51. Therefore, along with the movement of the conveyor device 1, the sand mold upper surface temperature measuring device 3 linearly measures the sand mold upper surface in the transport direction and outputs it to the microcomputer device 4. The sand mold upper surface temperature measuring device 3 is the reference position of the casting extracting device 2.
It is arranged at a sensor reference position x1 upstream of x2 and separated by a distance equal to the dimension (2Lo) in the transport direction of the two sand molds. Then, during one measurement (one operation period of the conveyor device 1), the sensor measures the conveyor transport distance Lo in the upstream direction from the sensor reference position x1.

Therefore, assuming that the distance from the sensor reference position x1 to the center position of the gate is Δx, it is sufficient to move the casting extracting device 2 in the transport direction by Δx in the next next casting extraction. In this case, the displacement of the sand mold 51 while the sand mold 51 moves from under the sand mold upper surface temperature measuring device 3 to below the casting pulling device 2 is ignored.

The temperature of the upper surface of the sand mold 51 is 200 ° C. or less according to the actual measurement, and the temperature of the gate 54 is about 500 ° C. Therefore, the sensitive wavelength band of this radiation thermometer using an infrared filter is 3 ° C.
It is set to about μm to 0.8 μm, and further to about 2 μm to 1 μm. In such a wavelength band, the energy of infrared rays generated from sand is insignificant, which is advantageous for separating sand from the gate.

 The results of the actual measurement of the temperature of the upper surface of the sand mold are shown below.

Center position of the gate: 391 ° C to 567 ° C, average 494 ° C Sand surface near the gate: 78 ° C to 173 ° C, average 130 ° C Sand surface between the gates: 77 ° C to 149 ° C, average 114 ° C Is caused by the time elapsed since the start of the line, fluctuations in temperature, fluctuations in various line speeds, and the like.

The low-pass filter 6 cuts off the high-frequency component of the output signal voltage (sand-type upper surface temperature signal) V from the sand-type upper surface temperature measuring device 3 and sends only the low-frequency component VL to the A / D converter 7. The A / D converter 7 A / D converts the low frequency component VL,
The digital sand mold upper surface temperature signal Vdd is input to the microcomputer device 4.

The microcomputer device 4 calculates the center position m of the gate by calculating the digital sand mold upper surface temperature signal Vdd, obtains the position (drawing position) of the casting part 56 from the obtained center position m of the gate, and sets the casting extracting device 2 It has a function of moving in the transport direction and moving above the pull-out position. Then, the microcomputer device 4 lowers the casting withdrawing device 2 to pierce the pair of extraction arms 22 and 23 on both sides in the transport direction of the plan portion 56 (see FIG. 2), and then bring the extraction arms 22 and 23 close to each other. (See FIG. 3), and the plan part 56 is gripped. Next, after the casting unloading device 2 is pulled up (see FIG. 4), it is moved along the rail 20, and is hooked on a hanger of a hanger conveyor (not shown) by a robot (not shown).

Hereinafter, the detailed operation of the microcomputer device 4 will be described with reference to FIGS.
This will be described with reference to the signal waveform diagram shown in the figure and the flowchart shown in FIG.

First, initialization is performed in S10, and the process waits until the conveyor start signal S1 is input (S12). The conveyor start signal S1 and the conveyor stop signal S2 are input to the microcomputer device 4 from a central control device (not shown) for controlling the conveyor device 1.
When the conveyor start signal S1 is inputted, the digital sand mold upper surface temperature signal Vdd is received from the sand mold upper surface temperature measuring device 3 via the comparator 6 and the A / D converter 7, and at the same time, the conveyor movement distance signal Vz from the conveyor movement detecting means 8. Is received (S14). More specifically, the conveyor moving distance signal Vz outputs a pulse signal each time the conveyor device moves a small fixed distance, and the microcomputer device 4 samples the digital sand mold upper surface temperature signal Vdd every time the pulse signal is input. And sequentially store them in the storage area. Therefore, the digital sand mold upper surface temperature signal Vdd sequentially accumulated in the storage area in one measurement is a row of data measured at regular intervals in the transport direction.

When the conveyor stop signal S2 is input (S16), the flag F indicating whether or not the previously measured data is held in the storage area is checked (S18). The flag F is 0, and the previously measured data is stored in the storage area. If not,
Return to S12. If the previously measured data is held in the storage area, the flag F is set to 1 (S22), and the received digital sand mold upper surface temperature signal Vdd is processed.
, The middle position in the transport direction, that is, the gate center position m,
The transport direction coordinate positions L1 and L2 of the gate position m are obtained (S22). However, the transport direction coordinate positions L1 and L2 indicate the distance from the sensor reference position x1. The gate center position calculation subroutine (S22) is executed as follows. That is, the digital sand mold upper surface temperature signal Vdd (hereinafter, referred to as present data) stored in the current storage area and the digital sand mold upper surface temperature signal Vdd (hereinafter, referred to as previous data) stored in the storage area during the previous conveyor operation period. Digital sand mold top surface temperature signal Vdd for two transport distances (2Lo)
Is binarized by a predetermined threshold voltage Vt to obtain a binarized signal Vd, a midpoint between the rising edge and the falling edge of the high temperature region Sm corresponding to the level 1 region of the binarized signal Vd. Is determined as the gate position m (see FIG. 10). In this embodiment, the threshold voltage Vt is equal to the threshold temperature Tt.
(300 ° C.) (see FIG. 9). In FIG. 1, two gate positions m are detected by one image pickup. However, when the gate position m is located near the sensor reference position x1 (the center of the image pickup area), 1 gate position m is detected. 1 times
The center position m of each gate is detected. However, when two gate positions m are detected by one imaging, the gate position on the downstream side in the transport direction is the gate position m to be detected this time. When one end of the high-temperature region Sm (see FIG. 10) is hung on either end of the imaging region, the center position m of the high-temperature region Sm cannot be accurately detected. The center position m of the high-temperature region (gate region) Sm (on the upstream side in the transport direction) is obtained.

Next, the difference (L2-x1) between the coordinate position L2 in the transport direction and the sensor reference position x1 obtained by the operation of calculating the center position m of the gate before last time.
Only the casting unloading device 2 is moved in the transport direction (S2
Four). This is because the casting extraction device 2 is located two sand molds 51 downstream. Upon arrival at this target position (S26), the above-described casting extraction is performed by the casting extraction device 2 (S28).

As described above, the frameless casting line of this embodiment uses the gate position m as the gate position determining means to determine the center position of the high temperature region Sm exceeding the preset threshold temperature Tt as the gate position m.
Therefore, for example, the gate position determination is easier and more accurate than in the case where the front end or the rear end of the gate 54 is determined and recognized as the gate position.

(Modification) In the above embodiment, one sand mold upper surface temperature measuring device 3 is fixed above the conveyor device 1, but on a line parallel to the conveying direction, it is closer than one conveying distance Lo to 2 A plurality of sand mold upper surface temperature measuring devices 3 may be provided.

For example, when two sand mold upper surface temperature measuring devices 3 are provided at a distance of 0.5 conveyance distance (0.5Lo) from each other, 1.5 sand conveyance is performed during one conveyor operation period by synthesizing both sand mold upper surface temperature signals V. Only the length (1.5 Lo) can be measured, and at least one gate 54 can be completely measured.

Of course, more sand mold upper surface temperature measuring devices 3 can be arranged in parallel in the transport direction.

Embodiment 2 Another embodiment of the present invention will be described with reference to the block diagram of FIG.

This frameless casting line has the same device configuration as the device of the first embodiment except for a sand mold upper surface temperature detecting device (sand mold upper surface sensor) 3.

That is, the sand mold upper surface sensor 30 of this embodiment detects the gate 54 made of cast iron having a high magnetic permeability, and is disposed 10 cm above the sand mold upper surface of the frameless sand mold row 5 upward. The magnetic head 31 oscillates at a frequency of about 100 KHz and the resistance 33
Oscillator for supplying an oscillating voltage to the magnetic head 31 via the
32, tuning amplifier 3 for tuning and amplifying the output voltage of the magnetic head 31
4. A detector 35 for detecting the output voltage of the tuning amplifier 34.

The operation of the sand type upper surface sensor 30 will be described.The magnetic head 31 has a high impedance when the gate 54 is in proximity, and has a low impedance when the gate 54 is separated.As a result, the output voltage Va of the AC oscillator 32 is Magnetic head
31 and the tuning amplifier 34 is moved by the gate 54
The AM modulated signal is tuned and amplified. The detector 35 performs full-wave rectification of the tuned and amplified signal voltage, and outputs a low-pass filter 6.
Extracts the required low-frequency signal component from the signal voltage output from the detector 35 and sends it to the A / D converter 7.

Embodiment 3 Another embodiment of the present invention will be described with reference to the block diagram of FIG.

This frameless casting line has the same device configuration as the device of the first embodiment except for a sand mold upper surface temperature detecting device (sand mold upper surface sensor) 3.

That is, the sand type upper surface sensor 300 of this embodiment detects the gate 54 made of cast iron having a high magnetic permeability,
A magnetic head 301 disposed above the sand mold upper surface of the frameless sand mold row 5 at a distance of 10 cm, a capacitor 302 connected in parallel with the magnetic head 301, an FM modulation oscillator 303 having the magnetic head 301 and the capacitor 302 as load capacitances. , A band filter 304 for extracting a necessary signal frequency band, an amplitude limiter 305 for slicing an amplitude equal to or more than a predetermined value, and an fV converter 306.

The operation of the sand type upper surface sensor 30 will be described. The magnetic head 31 has a high reactance when the gate 54 is in close proximity,
When the gate 54 moves away, the reactance becomes low, and as a result,
The FM modulation oscillator 303 outputs an FM modulation signal voltage having a high frequency when the gate 54 is far away and a low frequency when the gate 54 is close. From this FM modulation signal voltage, the bandpass filter 304 extracts a signal frequency component near the carrier frequency, the amplitude limiter 305 slices the amplitude above a certain value to reduce noise components, and the fV converter 306 performs FM detection. The DC signal component is sent to the microcomputer device 4 via the low-pass filter 6 and the A / D converter 7 as in the first and second embodiments.

Embodiment 4 Another embodiment of the present invention will be described with reference to the block diagram of FIG.

This frameless casting line has the same device configuration as the device of the first embodiment except for a sand mold upper surface temperature detecting device (sand mold upper surface sensor) 3.

That is, the sand mold upper surface sensor 30 of this embodiment detects the gate 54 made of an aluminum alloy, and the magnetic head 31, which is disposed 10 cm upward from the sand mold upper surface of the frameless sand mold row 5, An AC oscillator 32 that oscillates at a frequency of about 500 KHz and supplies an oscillating voltage to a magnetic head 31 via a resistor 33, a tuning intensifier 34 that tunes and amplifies the output voltage of the magnetic head 31, and detects an output voltage of the tuning intensifier 34 Detector 35 to be used.

To explain the operation of this sand type upper surface sensor 30, about 500 KHz
The magnetic head 31 to which the high-frequency current is applied induces a high-frequency magnetic field near the downward gap, and an eddy current is induced in the aluminum alloy gate 54 by the high-frequency magnetic field. Since a large eddy current has the same meaning as a decrease in the impedance of the magnetic head 31, the input voltage to the tuning amplifier 34 decreases. That is, the input voltage to the tuning amplifier 34 has a low amplitude when the gate 54 is close and a high amplitude when the gate 54 moves away. As a result, the gate 54 can be detected as in the case of the second embodiment. .

If the sand-type upper surface sensors of Embodiments 2, 3, and 4 described above are used, the gate position is magnetically detected.
54 has the advantage that it can be detected without any problem even if it is covered with sand, and also has the advantage that it is more resistant to dust, dust and water vapor than optical detection.

Of course, the sand-type upper surface sensors of the second, third, and fourth embodiments can be applied to the gate 54 of another material.

An ultrasonic sensor, a laser sensor, or the like may be used in addition to the above-described sand type upper surface sensors.

For example, when an ultrasonic oscillator irradiates an ultrasonic wave at a high frequency and focused on one point of the sand mold upper surface to the sand mold upper surface and detects the echo, the scattering of the echo is large because the unevenness is large on the sand surface, and the spout 54 In this case, there are few irregularities and the echo is reflected almost vertically.

In addition, when a laser beam is radiated from the laser to the sand mold upper surface at a point on the sand mold upper surface and the reflected light is detected, since the unevenness is large on the sand surface, the scattering of the reflected light is large, and the spout 54 has little unevenness and the reflected light is almost Reflects vertically.

Therefore, if an ultrasonic sensor or an optical sensor is provided at a position at an angle of about 45 to 80 degrees, preferably 75 degrees with respect to a virtual vertical line penetrating the irradiation point on the vertical upper surface, these ultrasonic sensors Alternatively, the optical sensor outputs a large signal voltage with respect to the reflected signal from the sand surface, and outputs a small signal voltage with respect to the reflected signal from the gate. As a result, if the output signal voltage of these ultrasonic sensors or optical sensors is processed in the above embodiment, the gate position can be determined.

[Effects of the Invention] As described above, according to the frameless casting line of the first aspect of the present invention, the gate and the casting (product part) are located below the gate, based on the position of the gate in the transport direction. Estimate the position in the transport direction of the runner section connecting
Since the extraction arm of the casting extraction device is moved and engaged with the extraction position, the following operation and effect can be achieved.

First, the position of the sprue is detected, and the spout is engaged with the runner at least in the transport direction and is extracted to the position of the sprue.
Even if sand mold deformation such as opening, collapse, shrinkage, etc. occurs, these sand mold deformations do not affect the extraction position determination at all, even if the casting position is slightly inclined due to these sand mold deformations, the detection position is Yes, since there is a runner part where the extraction position is close to the sprue in the transport direction, the inclination reduces the distance that the runner part deviates from the sprue in the transport direction, so it engages with casting parts other than the runner part. As a result, the number of failures in extraction can be reduced as compared with separating the casting from the sand mold.

In addition, the casting is pulled out upward and the extracted casting is held swingably. Due to this, even if the position of the extracted casting is broken due to the sand mold deformation or the like, the extracted casting swings by its own weight around the runner portion as a swing center, so that the casting has a constant posture, Handling after extraction is facilitated.

Furthermore, since the extraction arm of the casting extraction device engages with the runner portion and extracts it upward, the casting extraction device does not need to descend until it comes into contact with the casting (product), and the extraction will fail. Even if such a case occurs, the casting (product) is not damaged.

Next, according to the frameless casting line of the second aspect of the present invention, since the magnetic sensor for magnetically detecting the gate is employed as the sand mold upper surface sensor, the following operation and effect are achieved as compared with the conventional gate detection sensor. be able to.

First of all, since it is a non-contact type, dirt and sand do not bite in rotating or sliding parts as compared with a contact type, and the gate can be detected reliably even if the sand mold upper surface is tightly tightened, Extremely high reliability.

Next, the position of the gate can be detected more accurately as compared with a sensor that detects the gate automatically or thermally as a non-contact sensor (a sensor that determines the gate by temperature or color).

More specifically, when pouring the molten metal into the sprue, sand pouring or spilling often occurs at the sprue, and as a result, the thermal or optical shape of the sprue surface often becomes irregular, and its exact center position Seeking is not easy.

On the other hand, when the sprue is detected magnetically, even if it is covered with sand, the sprue hidden under it can be detected accurately and in a non-contact manner. Since the magnetic resistance is larger or the eddy current loss is smaller than that of the true gate part, a slight error occurs, but the gate position can be detected much more accurately than in the case of thermal or optical detection.

[Brief description of the drawings]

FIG. 1 to FIG. 4 are block diagrams sequentially showing a casting withdrawing operation in one embodiment of the frameless casting line of the present invention.
The figure is a schematic perspective view showing an example of an abnormal sand mold in a frameless sand mold row, FIG. 6 is a plan view of the casting A in FIG. 1, FIG. 7 is a plan view of an end portion of the conveyor device 1, and FIG. FIG. 9 is a side view of an end portion of the apparatus 1, FIG. 9 is a top view of a sand mold upper surface temperature distribution chart of the frameless sand mold row 5 at the end section of the conveyor apparatus 1, FIG. 10 is a signal waveform diagram showing signal waveforms of each section, and FIG. 6 is a flowchart of the device 4. FIGS. 12, 13, and 14 are block diagrams showing another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Conveyor device 2 ... Cast removal device 3 ... Sand mold upper surface temperature measuring device (Sand mold upper surface sensor) 4 ... Microcomputer device (Sluice position determination means) (Cast removal position determination means)

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 1-215438 (JP, A) JP-A 64-83370 (JP, A) JP-B 64-7013 (JP, B2)

Claims (2)

(57) [Claims] 1. A conveyor device for intermittently conveying a frameless sand mold row composed of a plurality of sand molds connected in a row in a traveling direction and each having a gate, and a conveyor arm having a pull-out arm for extracting a casting from the sand mold. A casting extractor disposed above the distal end, a sand upper surface sensor disposed above the distal end of the conveyor device for detecting the state of the upper surface of the sand mold, and processing an output signal of the sand upper surface sensor. A gate position determining means for determining the position of the gate in the transport direction; and a casting removal position determining means for determining a removal position of the casting removal device based on the determined position of the gate. The casting arm is engaged with a runner section connecting the gate and the casting (product part) based on the extraction position, and the casting is swung upward. Unframed casting lines, characterized in that to extract. 2. A conveyor device for intermittently transporting a frameless sand mold row composed of a plurality of sand molds connected in a row in a traveling direction and each having a sprue, and a conveyor arm having a drawing arm for extracting a casting from the sand mold. A casting extractor disposed above the distal end, a sand upper surface sensor disposed above the distal end of the conveyor device for detecting the state of the upper surface of the sand mold, and processing an output signal of the sand upper surface sensor. A gate position determining means for determining the position of the gate in the transport direction; anda casting removal position determining means for determining a removal position of the casting removal device based on the determined position of the gate, the sand mold upper surface sensor includes: And a frameless casting line for detecting the gate magnetically.