JPH02299766A - Instrument for inspecting deformation of sand mold - Google Patents

Abstract

PURPOSE:To accurately and quickly discriminate deformation of cavity by calculating deforming quantity of the cavity from inner wall face distance measured with a first distance sensor and the reference wall face distance measured with a second distance sensor. CONSTITUTION:The inner wall face distance (d1) and the reference wall face distance (d2) are detected with distance sensors 6a, 6b, respectively. The inner wall face distance (d1) denotes the distance between the inner wall face 4a at front part of a sand mold 8 and the first distance sensor 6a, and the reference wall face distance (d2) denotes the distance between the reference wall face 74 of a mold 7 and the second distance sensor 6b. Distance Dx of the wall face between the inner wall face 4a and the reference wall face 74 is calculated from the wall face distances (d1), (d2), and difference DELTAx between the prestored distance Dxo of the reference wall face and the distance Dx is obtd. The distance Dxo of the reference wall face corresponds to the distance Dx of the wall face when the deformation of the cavity 80 is not generated and is the fixed value. Successively, degree of the absolute value in the difference DELTAx = Dx - Dxo is checked, and when this is large, sand mold fail signal is outputted and when not, a lifting member 3 is ascended by the fixed distance.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a sand mold deformation inspection device for inspecting deformation of a sand mold due to transportation or the like.

[Prior art] In an example of a conventional mold making line, a pair of L side and lower sand molds formed by a sand mold making machine are conveyed by a conveyor, and before a pouring machine, they are overlapped and sealed inside. A mold with a hollow cavity is formed, and then the metal is poured into the mold.

In this conventional mold making line, large and heavy casting boxes are transported by a series of intermittent operations of the conveyor, so the mechanical VfI' when the conveyor starts and stops! f!
There was a problem in that the shape of the sand mold cavity was deformed before pouring due to force.

Conventionally, to inspect this cavity deformation, the mold making line was temporarily stopped and the cavity shape was manually measured using a specially made gauge to avoid destroying it.

[Problem to be solved by the invention] However, in the conventional inspection method described above, it is necessary to stop the VI molding line for a long time to inspect each part of the cavity, and a large labor burden is incurred when conducting a sampling inspection. Ta. Furthermore, since the sand mold to be measured is brittle, new defective products may be produced.

It has been a long-held dream of our industry to automatically inspect sand molds for chipping and biting deformation, but it is not possible to measure cavity dimensions from a sand mold while it is being moved on a conveyor in a mold making line. It was also difficult to accurately hold the sand mold at a predetermined position relative to the inspection device.

The present invention has been made in view of these problems, and provides a sand mold deformation inspection device that can perform inspection efficiently in a short time even if there is some relative positional variation with respect to the inspection device, and does not deform the cavity. This is an issue that needs to be solved.

[Means for Solving the Problems] The sand mold deformation inspection device of the present invention includes a base portion disposed along a V1 manufacturing line for conveying a casting box in which a sand mold is molded, and a sand mold deformation inspection device that is movably held in the base portion. The distal end is fixed to the sand mold's key (p biddy) and the sear member, and the inner wall surface distance t1 is measured to the inner wall surface of the sand mold that partitions the cavity. a non-contact first distance sensor; a second distance sensor that is fixed to the lifting member and measures a wall distance to a reference wall provided in the casting box; The sand mold deformation determining means is provided, which calculates the amount of deformation from the reference wall surface distance, and determines the success or failure of the sand mold based on the magnitude of the calculated amount of deformation. It is characterized by

As the non-contact first distance sensor, an optical sensor, an ultrasonic sensor, or the like can be used.

[Operation] The elevating member descends and inserts the first distance sensor into the cavity of the sand mold, causing the first distance sensor to face the inner wall surface to be measured and the second distance sensor to face the reference wall surface. First,
The second distance sensor detects the inner wall surface distance and the reference wall surface distance to the inner wall surface and the reference wall surface, respectively, and the cavity deformation calculation means calculates the amount of cavity deformation from these distances. For example, since the inter-sensor distance between the first and second distance sensors is known, if the inner wall surface distance and the reference wall surface distance are subtracted from this inter-sensor distance, the distance between the inner wall surface and the semi-wall surface that partitions the cavity can be reduced. The distance between surfaces can be calculated.

If there is no cavity deformation, this distance between surfaces matches the distance between surfaces of the known target (11), so the amount of cavity deformation can be determined from the difference between the calculated distance between surfaces and the distance between surfaces of the target.Sand mold deformation determination means Based on the magnitude of the calculated cavity deformation m, it is determined that the sand mold is defective if the difference is large, and that the sand mold is good if the difference is small.

[Example] (Example 1) Fig. 1 is a partial cross-sectional schematic side view of an embodiment of the sand deformation inspection device of the present invention, and Fig. 2 is a schematic cross-sectional plan view taken along the line 8-1'. As shown in the figure.

This sand mold deformation testing device consists of a base 1 having a hydraulic cylinder 2;
, a gastric descent member 3 fixed to the piston rod 21 of the hydraulic cylinder 2, and a non-contact type first member fixed to the elevating member 3.
It consists of a distance sensor 6a, a second distance sensor 6b, a third distance sensor 6C, and a signal processing device 4 that constitutes a gap dimension cylinder means and a sand mold deformation determining means in the present invention.

The base 1 is installed between a sand mold forming machine (not shown) and a pouring machine (not shown) that constitute a casting line, and is erected on the side of a roller conveyor 5 for conveyance. A head 11 of the base 1 extends above the roller conveyor 5, and a hydraulic cylinder 2 is fixed to the head 11. The piston rod 21 of the hydraulic cylinder 2 extends vertically, and the tip of the piston rod 21 is connected to the roller conveyor 5.
is facing.

The elevating member 3 has a shape consisting of a main part 31 and a pair of protrusions 32 and 33, and the main part 31 is fixed to the tip of the piston rod 21 and extends in the horizontal direction. Projection 32.33
extend downward from both ends of the main portion 31, and the protrusions 32.3
First and second distance sensors 6a and 6b are fixed to the tip of the sensor 3 to measure horizontal distance. First and second distance sensors 5a.

6b are arranged so as to face each other. Further, the third distance sensor 6C is fixed to the lower surface of the main portion 31 to measure the vertical distance. Each of the distance sensors 6a to 6C is an optical distance sensor. Each distance sensor 6a
6C is a distance sensor that has a light emitting diode (not shown) and a PSD (not shown) and measures the distance bait 1 to the measurement target by triangulation method, but detailed explanation will be omitted.

The signal processing device 4 is composed of a microcomputer, and is programmed to operate the hydraulic cylinder 2 in synchronization with the roller conveyor 5, and to process the signals from the respective distance sensors 6a to 6C to determine the quality of the sand mold. has been done.

On the schematically illustrated roller conveyor 5, a square box-shaped casting box 7 made of steel plate is placed between the upper ends.
The sand in the casting box 7 is filled with L8. The long side of the casting box 7 is about 1 m, the short side is about 0.5 m, and the height is about 3 Qcm. The small assembly weighs approximately 170 kg, and several dozen casting boxes 7 are mounted on an interval-operated roller conveyor 5.The mating surface 81 of the sand mold 8 is
It is molded on the same straight line as the front end upper surface 71 and rear end upper surface 72 of Jffi7, and extends in the horizontal direction in an ideal state without deviation. Further, the front end surface 73 of the casting box 7 is
A front end surface 73 extending in a direction perpendicular to the front end upper surface 71 and rear end upper surface 72 and in a direction perpendicular to the conveyance direction.
A vertical groove-shaped recessed surface 74 is recessed in the center of the front end surface 73 in parallel with the front end surface 73.

The sand mold 8 has one rectangular parallelepiped-shaped cavity 80 with an open top end.
The inner wall surfaces 4a to 4d of the sand mold 8 define the side surfaces of the cavity 80 (see FIG. 2). sand mold 4
The front inner wall surface 4a is formed parallel to the reference wall surface 74 of the casting box 7.

In FIG. 1, the piston rod 21 is extended and the first distance sensor 6a is inserted into the cavity 80.
The second distance sensor 6b faces the reference wall surface 74, and the third distance sensor 6C4 faces the front end upper surface 71 of the casting box 7.

Next, the measurement operation of this sand mold deformation head will be explained with reference to the flowcharts of FIGS. 3 and 4.

First, after initializing the microcomputer 4, a detection device (not shown) such as a limit switch detects whether or not the casting box 7 has stopped at a predetermined position directly below the lifting member 3 (31
00). The roller conveyor 5 is operated at intervals, and the operation of the roller conveyor 5 is controlled so that the casting boxes 7 are sequentially stopped at a predetermined position immediately below the elevating member 3.

When it is detected that the casting box 7 has stopped at a predetermined position directly below the elevating member 3, the hydraulic cylinder 2 is activated to lower the elevating member 3 (3102>, and it is determined whether the elevating member 3 has descended to a predetermined position. (3104).This determination is based on the front end upper surface 71 of the casting box 7 measured by the third distance sensor 6C.
vertical distance dh is preset vertical pressure 1iSll
It is executed after determining whether it is less than or equal to the value.

When the elevating member 3 has descended to the predetermined position, the lowering of the elevating member 3 is stopped (3106), and a test number flag T indicating the number of tests is set to T+1.

However, the flag T is initially set to O immediately after the start, and is set to 1 here. (S108).

Next, the inner wall surface distance d1 and the reference wall surface distance d2 are detected by each distance sensor 6a, 6b (3110). however,
The inner wall surface distance d1 means the distance between the inner wall surface 4a of the front part of the sand mold 8 and the first distance sensor 6a, and the reference wall surface distance d2 means the distance between the reference wall surface 74 of the casting box 7 and the second distance sensor 6b. means the distance.

Next, from these wall distances di and d2, the wall distance Dx between the inner wall surface 4a and the reference wall surface 74 is calculated, and the calculated wall distance [)X and the pre-stored standard wall distance DXO are calculated.
The difference ΔX is calculated (S112). Here, the standard wall-to-wall distance DXO means the wall-to-wall distance DX when the cavity 80 is not deformed, and is a constant value. That is, since the wall thickness of the casting box 7 remains unchanged, a change in the wall distance DX is equal to a change in the wall thickness of the sand mold 8.

Next, check the magnitude of the absolute value of the difference Δx = Dx - DXO (S
114), if it is large, output a sand mold failure signal 8116
), otherwise the elevating member 3 is raised by a certain distance (811B). Note that when a sand mold defect signal is output, a signal to stop pouring into the sand mold 8 is output to a pouring machine (not shown), and pouring into the defective sand mold 8 is stopped.

Next, the process advances to 5120 where the number of inspection flag T is set to the set value n(
Here, determine whether it is less than or equal to 5), and if it is less than or equal to 81
Return to step 08 and check the quality of the sand mold 8 again, and if the number of inspections exceeds the set value n, output a sand mold good signal.512
2>, raise the elevating member 3 to the initial position and move the conveyor 5
(3124>. In this embodiment, the lifting and inspection of the lifting member 3 were performed alternately, but the inspection was performed at fixed time intervals while vertically moving the lifting member 3 at a constant speed. The test may be carried out only once, or the test may be carried out only once.
In this embodiment, the inner wall surface 4a is formed of a plane extending vertically and perpendicular to the conveying direction, but may have other surface shapes. For example, you can memorize the changes in the standard wall distance DxO in the vertical direction, and move the mark at the same vertical position as the calculated wall distance Dx to [Wall distance DXO].
All you have to do is read out the .

Note that when the attitude of the sand mold 8 changes, the wall-to-wall distance DX may change, but in order to prevent this, for example, as shown in FIG. In addition, a guide roller 9 may be provided at right angles to the roller conveyor 5. If you do this, the large 1f
The fl casting box 7 is attached to the guide roller 9 with its own ff1ffi.
The posture of the sand mold 8 is precisely defined, excluding variations in the resting position in the conveyance direction.

The sand mold inspection apparatus of this embodiment described above has the following advantages.

(1) The stopping position of the casting box 7 inevitably varies in the conveying direction depending on the startup/stop status of the conveyor. Despite the existence of this variation, the amount of cavity deformation can be accurately measured.

(2) A signal to stop pouring into the sand mold 8 determined to be defective is output to the pouring machine (not shown), which reduces waste of molten metal and eliminates the trouble of sorting and processing defective products. can.

In addition, as a modification of this embodiment, the inner wall surface 4 to be inspected
When a is parallel to the reference wall surface 74, the quality of the sand mold 8 can be determined based on the magnitude of variation in the measured inner wall surface distance and the total distance of the base 71 (wall surface distance).

FIG. 6 shows the deformed form. A sand mold 8a having two cavities 81 and 82 is formed in the casting box 7a. The elevating member 3 has three protrusions 34, 35, and 36.
A first distance sensor 6a is located at the tip of the protrusion 35, and a second distance sensor 6a is located at the tip of the protrusion 35.
The distance sensor 6b is connected to the fourth distance sensor 6 at the tip of the protrusion 36.
d is fixed. The first distance sensor 6a measures the inner wall surface 4f of the cavity 81, and the fourth distance sensor 6d measures the inner wall surface 4g of the cavity 82.

(Example 2) FIG. 7 is a partial cross-sectional schematic side view of the sand mold deformation testing device of this example, and FIG. 8 is a schematic cross-sectional plan view taken along the line A-A.
As shown in the figure. However, elements having functions common to those of the first embodiment are given the same reference numerals.

This sand mold deformation testing device consists of a base 1 having a hydraulic cylinder 2;
, an elevating member 3 fixed to the piston rod 21 of the hydraulic cylinder 2, first to third distance sensors 6a to 6C fixed to the elevating member 3, and a signal processing device 4. It has a fifth distance sensor 6e fixed to No. 3.

The elevating member 3 includes a main portion 31 extending in the horizontal direction;
The main part 31 has a protrusion 32 extending downward from the lower surface of the front end thereof, and a protrusion 33 extending downward from the lower surface of the center of the main part 31. It is growing up to.

The fifth distance sensor 6e is an optical distance sensor 1eIII? It is fixed to the lower surface of the rear end of the main part 31 of the elevating member 3 in order to measure the vertical distance downward.

In FIG. 7, the rear end upper surface 72 of the casting box 7 is shown.

The measurement operation of this sand mold deformation testing device will be explained with reference to the flowchart of FIG.

This flowchart is the same as the flowchart of the first embodiment shown in FIG. It has been inserted.

8126 is the vertical distance 1i51Idh to the front end upper surface 71 of the casting box 7 measured by the third distance sensor 6C, and the fifth
This is a step of calculating the inclination rate of the casting box 7 along the transport direction from the vertical distance dh- from the rear end of the casting box 7 to the F surface 72 measured by the distance sensor 6e.

In other words, since the distance between the third and fifth distance sensors 1) 6C and 60 is known and constant, the above slope rate is (dh-dh
”)/L.

5128 is a step of correcting the distance between the wall surfaces MDX=dl, which was excluded in 5110, by the inclination rate of the casting box 7 calculated in 5126. That is, as can be seen from FIG. 10, the true distance between the walls [)X- is as follows: □x-=cosθXDX tanθ=(dh-dt)'')/L.

By doing so, it is possible to correct errors caused by the inclination of the casting box 7 in the transport direction.

[Effects of the Invention] As explained above, the sand mold deformation inspection device of the present invention has a first
, has a second distance center, and calculates the amount of KiA-biti deformation from the inner wall surface distance measured by the first distance sensor and the reference wall surface distance measured by the second distance sensor, so even if the sand mold and each Even if the relative distance to the distance sensor varies, cavity deformation can be determined accurately and quickly, and there is no risk of damaging the cavity due to this inspection.

[Brief explanation of drawings]

FIG. 1 is a partial cross-sectional schematic side view of the sand mold deformation testing device of the present invention; FIG. 2 is a schematic cross-sectional plan view thereof; FIGS. 3 and 4 are flow charts showing the operation of the sand mold testing device; FIG. 5 is a schematic front view showing an example of the method 11 for controlling the posture of the sand mold 8, and FIG. 6 is a partially sectional side view showing a modified form. FIG. 7 is a partial cross-sectional schematic side view of the sand mold deformation testing device of the second embodiment, FIG. 8 is a schematic cross-sectional plan view of the device shown in FIG. 7, and FIG. 9 shows the operation of the sand mold testing device of FIG. 7. The flowchart shown in FIG. 10 is an explanatory diagram showing the relationship between the inclination ratio of the casting box 7 and the wall distance [)X. 1... Base 3... Lifting member 6a... First distance sensor 6b... Second distance sensor 4... Microcomputer (cavity deformation calculating means) (sand mold deformation determining means) Patent applicant Aisin Takaoka Co., Ltd. company agent
Patent Attorney Hiroshi OkawaFigure 2Figure 6Figure 3Figure 4Figure 5Figure 8H-Dx・4

Claims (2)

[Claims] (1) a base disposed along a casting line for conveying a casting box with a sand mold molded therein; and an elevating member that is held movably up and down by the base and whose tip end is inserted into the cavity of the sand mold. a non-contact type first distance sensor that is fixed to the lifting member and measures an inner wall surface distance to an inner wall surface of the sand mold that partitions the cavity; and a first distance sensor that is fixed to the lifting member and measures the inner wall surface distance of the sand mold that defines the cavity; a second distance sensor that measures a reference wall surface distance to a reference wall surface provided in the inner wall surface; a cavity deformation calculation means that calculates a cavity deformation amount from the inner wall surface distance and the reference wall surface distance; A sand mold deformation inspection device characterized by comprising: sand mold deformation determining means for determining whether a sand mold is good or bad based on its size. (2) The sand mold deformation inspection device according to claim 1, wherein the determination is performed a plurality of times as the elevating member is displaced.