JP2018061989A - Core gripping method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a core gripping method capable of accurately gripping a core.SOLUTION: A core gripping method according to the present invention is a core gripping method to grip a core 20 by inserting expandable and contractible grip portions 14_1 to 14_4 that a plurality of pickers 12_1 to 12_4 comprise respectively into a plurality of holes 25, 26, 27_1 and 27_2 formed in the core 20 and expanding the grip portions 14_1 to 14_4. The core comprises, as a plurality of holes, positioning holes for determining the position of the core in an xy plane and grip holes for gripping the core. The positioning hole has a circular or nearly square sectional shape in the xy plane. When gripping the core, the grip portions of the positioning pickers inserted in the positioning holes are expanded to determine a position of the core in the xy plane and, after determining the position of the core in the xy plane, grip portions of the gripping pickers are expanded to grip the core.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a core gripping method.

  The casting core is a mold used to form a hollow portion in a casting to be produced. Traditionally, the core was manually placed in the mold. However, in recent years, it has become important to arrange the core with high precision in the mold as the casting becomes highly accurate. For this reason, a technique for arranging the core with high precision in the mold has become important.

  Patent Document 1 discloses a technique related to a transport device for transporting a casting core.

Japanese Translation of National Publication No. 05-509071

  As one of the methods for gripping the core, there is a method for gripping the core by using a plurality of pickers each having a grip portion that can expand and contract at the tip portion. In this method, gripping portions of the picker are inserted into a plurality of holes formed in the core, the gripping portions are expanded, and the picker is fixed to the core holes to grip the core.

  However, since a tolerance occurs in each hole formed in the core, a tolerance also occurs in the relative position of each hole. When the gripping portion is inflated in such a state where the tolerance is generated, the position of the core is shifted due to the relative positional relationship between the core hole and the picker gripping portion, and the position accuracy of the core is deteriorated. There is a problem.

  In view of the above problems, an object of the present invention is to provide a core gripping method capable of gripping a core with high accuracy.

  In the core gripping method according to the present invention, the expandable and contractible gripping portions provided in each of the plurality of pickers are respectively inserted into a plurality of holes formed in the core, and the gripping portions are expanded to expand the core. This is a core gripping method for gripping the core. The core includes, as the plurality of holes, a positioning hole for determining the position of the core on a reference plane perpendicular to the picking-up / lowering direction of the picker, and a gripping hole for gripping the core. The cross-sectional shape of the positioning hole at the reference surface is a circle or a substantially square. Then, when gripping the core, the gripping portion of the positioning picker inserted in the positioning hole is expanded to determine the position of the core on the reference plane, and the position of the core on the reference plane Then, the gripping part of the gripping picker inserted in the gripping hole for gripping the core is expanded to grip the core.

  In the core gripping method according to the present invention, when the core is gripped, after the gripping portion inserted in the positioning hole for determining the position of the core is expanded to determine the position of the core, The core is gripped by inflating the gripping part inserted in the gripping hole for gripping the core. Therefore, since the core is fixed by positioning the core first, the gripping portion of the gripping picker is then expanded to prevent the core from being displaced when the core is gripped. Can do.

  According to the present invention, it is possible to provide a core gripping method capable of gripping a core with high accuracy.

It is a front view which shows the core holding | gripping apparatus concerning embodiment. It is a top view which shows the core holding | gripping apparatus concerning embodiment. It is a perspective view which shows an example of a core. It is a side view which shows the state which has hold | gripped the core using the core holding | grip apparatus. It is a flowchart for demonstrating the core holding | grip method concerning embodiment. It is a top view for demonstrating an example of the core holding | grip method concerning embodiment. It is a top view for demonstrating the other example of the core holding | grip method concerning embodiment.

Embodiments of the present invention will be described below with reference to the drawings.
1 and 2 are a front view and a top view, respectively, showing the core gripping device according to the present embodiment. As shown in FIG. 1, the core gripping device 1 includes a support portion 10 and a plurality of pickers 12_1 to 12_4. The plurality of pickers 12 </ b> _ <b> 1 to 12 </ b> _ <b> 4 are arranged to extend downward from the lower surface of the support portion 10 (z-axis minus direction) and are fixed to the support portion 10. Since the support part 10 and the pickers 12_1 to 12_4 need to grip and support the core, a certain degree of strength is required. For example, the support part 10 and the pickers 12_1 to 12_4 can be configured using a metal material.

  Grip portions 14_1 to 14_4 are provided at the tips of the plurality of pickers 12_1 to 12_4. The gripping portions 14_1 to 14_4 are configured to be able to expand and contract using a fluid such as a gas or a liquid (which will be described below using a gas as an example), and are configured using an elastic member such as rubber, for example. can do. For example, the gripping portions 14_1 to 14_4 can be configured using rubber balloons. Gas (compressed air) is supplied to each holding | gripping part 14_1-14_4 via piping (not shown).

  Specifically, the grip portion 14_1 can be expanded by supplying compressed air having a predetermined pressure to the grip portion 14_1. The compressed air is supplied from a compressor or the like (not shown) to the gripping part 14_1 via a pipe. Further, when the gripping part 14_1 is in an expanded state, the pressure in the gripping part 14_1 can be reduced by opening an exhaust valve (not shown) of the pipe connected to the gripping part 14_1. 14_1 can be contracted. The same applies to the other gripping portions 14_2 to 14_4.

  In the present embodiment, the pickers 12_1 and 12_2 are positioning pickers, and the pickers 12_3 and 12_4 are gripping pickers. Hereinafter, the pickers 12_1 and 12_2 may be referred to as positioning pickers 12_1 and 12_2, and the pickers 12_3 and 12_4 may be referred to as gripping pickers 12_3 and 12_4.

  As shown in FIG. 2, the positioning pickers 12_1 and 12_2 are arranged so as to be aligned with each other in the x-axis direction. Further, the gripping pickers 12_3 and 12_4 are arranged so as to be aligned with each other in the x-axis direction. Further, on the lower surface of the support portion 10, the positioning pickers 12_1 and 12_2 are arranged on the y-axis direction plus side, and the gripping pickers 12_3 and 12_4 are arranged on the y-axis direction minus side, respectively.

  Further, the positioning picker 12_1 and the positioning picker 12_2 are configured to expand and contract at independent timings. The gripping picker 12_3 and the gripping picker 12_4 may be configured to expand and contract at the same timing, or may be configured to expand and contract at independent timings.

  FIG. 3 is a perspective view showing an example of the core. As shown in FIG. 3, the core 20 has a core main body 21 and a baseboard 22. The core main body 21 is formed with cores 24_1 to 24_4 for forming hollow portions in the casting. Each of the cores 24_1 to 24_4 has the same shape, and the cores 24_1 to 24_4 are placed in the molds of the respective castings for casting, thereby corresponding to the cores 24_1 to 24_4 of the casting. A hollow part can be formed.

  The baseboard portion 22 is a portion provided so that the core 20 is stabilized when the core 20 is placed in a mold, and is formed by extending an end portion of the core body portion 21. For example, when the core 20 is placed in a mold, the baseboard 22 is supported by the mold. In addition, a plurality of holes 25, 26, 27 </ b> _ <b> 1, 27 </ b> _ <b> 2 for gripping the core 20 are formed in the baseboard portion 22. For example, the core 20 is formed using sand. For this reason, the core 20 is fragile, and sandfall or chipping occurs when it comes into contact with a mold or another core. For this reason, it is necessary to improve the accuracy at the time of gripping the core 20 and prevent it from coming into contact with a mold or another core.

  In the core 20 shown in FIG. 3, holes 25 and 26 are positioning holes for determining the position of the core in the xy plane. Here, in other words, the xy plane is a reference plane perpendicular to the ascending / descending direction (z-axis direction) of the pickers 12_1 to 12_4. In the core 20, holes 27_1 and 27_2 are gripping holes for gripping the core. Hereinafter, the holes 25 and 26 may be referred to as positioning holes 25 and 26, and the holes 27_1 and 27_2 may be referred to as gripping holes 27_1 and 27_2.

  The positioning picker 12_1 shown in FIGS. 1 and 2 is inserted into the positioning hole 25 shown in FIG. 3, and the positioning picker 12_2 shown in FIGS. 1 and 2 is inserted into the positioning hole 26 shown in FIG. . Further, the gripping pickers 12_3 and 12_4 shown in FIGS. 1 and 2 are inserted into the gripping holes 27_1 and 27_2 shown in FIG. 3, respectively.

  FIG. 4 is a side view showing a state where the core 20 is gripped using the core gripping device 1, and is a side view seen from the x-axis plus side. In the present embodiment, a plurality of pickers 12_1 to 12_4 are inserted into a plurality of holes 25, 26, 27_1, 27_2 formed in the core 20, and gripping portions 14_1 to 14 provided at the tips of the plurality of pickers 12_1 to 12_4 are provided. 14_4 is inflated to hold the core 20. That is, the pickers 12_1 to 12_4 and the baseboard portion 22 of the core 20 are fixed by expanding the gripping portions 14_1 to 14_4 inside the holes 25, 26, 27_1, and 27_2. In this state, the core 20 can be moved by moving the support portion 10 of the core gripping device 1 using a moving means (not shown).

  Next, the core holding method according to the present embodiment will be described in detail. FIG. 5 is a flowchart for explaining the core holding method according to the present embodiment. FIG. 6 is a top view for explaining an example of the core gripping method according to the present embodiment. In FIG. 6, the vicinity of the positioning holes 25 and 26 of the core 20 is shown in an enlarged manner in order to explain the positioning operation of the core 20 in detail. Below, operation | movement until it arrange | positions to the metal mold | die (not shown) the core 20 currently set | placed on the core mounting stand (not shown) using the core holding | grip apparatus 1 is demonstrated.

  First, the core gripping device 1 is moved to the place where the core 20 is placed (step S1). Specifically, the support unit 10 of the core gripping device 1 is moved using a moving means (not shown), and the coordinates on the xy plane of the core gripping device 1 are matched, and the core is placed on the core 20. The gripping device 1 is arranged. At this time, the pickers 12_1 to 12_4 (see FIG. 2) are arranged on the holes 25, 26, 27_1, 27_2 (see FIG. 3).

  Next, the support portion 10 of the core gripping device 1 is moved downward (z-axis minus direction) using a moving means (not shown). Accordingly, the pickers 12_1 to 12_4 are lowered, and the gripping portions 14_1 to 14_4 of the pickers 12_1 to 12_4 are inserted into the holes 25, 26, 27_1, and 27_2 (Step S2).

  As shown in FIG. 6A, the core 20 may be arranged so as to be shifted from a place (indicated by reference numeral 30) where the core is originally arranged. Here, as shown in FIG. 6B, the diameters of the holes 25, 26, 27_1, 27_2 are larger than the diameters of the gripping portions 14_1 to 14_4 (the contracted state) of the pickers 12_1 to 12_4. Is small. For this reason, when the pickers 12_1 to 12_4 are lowered, the gripping portions 14_1 to 14_4 are inserted into the holes 25, 26, 27_1, and 27_2. At this time, since the position of the core 20 is shifted from the original position (indicated by reference numeral 30), the center position 31 of the positioning hole 25 of the core 20 in the xy plane is the center position of the positioning picker 12_1 in the xy plane. Deviation from 33.

  Next, the gripping part 14_1 of the positioning picker 12_1 inserted into the positioning hole 25 is expanded (step S3). Accordingly, as shown in FIG. 6C, the core 20 moves to the reference position on the xy plane, and the position of the positioning hole 25 of the core 20 on the xy plane is determined. That is, the center position 31 in the xy plane of the positioning hole 25 of the core 20 can be matched with the center position 33 in the xy plane of the positioning picker 12_1.

  Next, in a state where the gripping portion 14_1 of the positioning picker 12_1 is inserted into the positioning hole 25 of the core 20 and the gripping portion 14_1 is inflated, the gripping portion 14_2 of the positioning picker 12_2 inserted into the positioning hole 26 Is expanded (step S4). Thereby, as shown in FIG.6 (d), the position of the rotation direction of the core 20 centering on the reference position (center position) 33 in xy plane can be determined. In FIG. 6D, the position of the core 20 in FIG.

  At this time, the pressure of the gripping portion 14_1 of the positioning picker 12_1 is adjusted so that the core 20 is rotatable about the positioning hole 25. (That is, make sure the pressure is not too high).

  Thereafter, the pressures of the gripping portions 14_1 and 14_2 of the positioning pickers 12_1 and 12_2 are increased to a predetermined pressure (step S5). Thereby, the position in the xy plane of the core 20 can be fixed. By such an operation, the core 20 (see FIG. 6A) that has shifted in the xy plane can be arranged and fixed at a position where it should be (see FIG. 6D).

  Here, the positioning hole 25 of the core 20 is a hole used for determining a reference position (x, y coordinates) in the xy plane of the core 20. Further, the positioning hole 26 of the core 20 is a hole used for determining the position of the core 20 in the rotation direction with the center position 33 being the reference position as the central axis.

  In the example shown in FIG. 6, the sectional shape of the positioning hole 25 in the xy plane is a circle. In this way, by making the cross-sectional shape of the positioning hole 25 on the xy plane circular, when the gripping part 14_1 of the positioning picker 12_1 expands, the side surface of the gripping part 14_1 abuts on the inner periphery of the positioning hole 25 The position of the positioning hole 25 in the xy plane can be determined with high accuracy.

  Moreover, in the example shown in FIG. 6, the cross-sectional shape in the xy plane of the positioning hole 26 is a long hole shape (ellipse shape). Thus, even if the position between the positioning hole 25 and the positioning hole 26 is shifted, the positional shift is absorbed by making the cross-sectional shape of the positioning hole 26 on the xy plane into a long hole shape. be able to. In other words, the tolerance between the positioning hole 25 and the positioning hole 26 can be absorbed.

  As shown in FIG. 5, after the positioning of the core 20 in the xy plane is completed, the gripping portions 14_3 and 14_4 of the gripping pickers 12_3 and 12_4 inserted into the gripping holes 27_1 and 27_2 (see FIG. 3) are expanded. The core 20 is gripped (step S6). At this time, the pressure of the gripping portions 14_3 and 14_4 is increased to a pressure at which the core 20 is securely gripped. At this time, the pressure of the gripping portions 14_1 and 14_2 of the positioning pickers 12_1 and 12_2 in the expanded state is set to be larger than the pressure of the gripping portions 14_3 and 14_4 of the gripping pickers 12_3 and 12_4 in the expanded state. Also good. By doing so, the core 20 can be firmly fixed using the gripping portions 14_1 and 14_2 of the positioning pickers 12_1 and 12_2, and the gripping portions 14_3 and 14_4 of the gripping pickers 12_3 and 12_4 are expanded. In this case, the position of the core 20 on the xy plane can be prevented from shifting.

  As shown in FIG. 5, after gripping the core 20 using each of the pickers 12_1 to 12_4, the support unit 10 of the core gripping device 1 is moved upward (z-axis plus direction) using a moving means (not shown). ). Thereby, each picker 12_1-12_4 raises and the core 20 is lifted (step S7).

  Thereafter, in a state where the core gripping device 1 is gripping the core 20, the core gripping device 1 is moved to the place where the mold is disposed and the core 20 is conveyed (step S8). And the support part 10 of the core holding | gripping apparatus 1 is moved to a downward direction (z-axis minus direction) using a moving means (not shown). Thereby, the core 20 is arrange | positioned in the predetermined place of a metal mold | die (not shown) (step S9). After the core 20 is arranged in the mold, the gripping portions 14_1 to 14_4 of the pickers 12_1 to 12_4 are contracted to raise the pickers 12_1 to 12_4. Thereby, each picker 12_1 to 12_4 is extracted from each hole 25, 26, 27_1, 27_2.

  As described above, in the core gripping method according to the present embodiment, when gripping the core, the gripping portion inserted in the positioning hole for determining the position of the core is expanded to expand the core. After the position is determined, the gripping part inserted in the gripping hole for gripping the core is expanded to grip the core. Therefore, since the core is fixed by positioning the core first, the gripping portion of the gripping picker is then expanded to prevent the core from being displaced when the core is gripped. Can do.

  In the above description, as shown in FIG. 6, the case where the cross-sectional shape of the positioning hole 25 in the xy plane is circular and the cross-sectional shape of the positioning hole 26 in the xy plane is a long hole shape has been described. However, in the present embodiment, as shown in FIG. 7, the cross-sectional shape of the positioning hole 45 in the xy plane may be substantially square, and the cross-sectional shape of the positioning hole 46 in the xy plane may be substantially rectangular.

  Hereinafter, the operation when the positioning hole 45 and the positioning hole 46 are substantially square and substantially rectangular respectively will be described with reference to FIGS. In the following description, the description overlapping with the operation described in FIGS. 5 and 6 is omitted as appropriate.

  Also in the case shown in FIG. 7, the support portion 10 of the core gripping device 1 is moved downward (z-axis minus direction) using a moving means (not shown). Accordingly, the pickers 12_1 to 12_4 are lowered, and the gripping portions 14_1 to 14_4 of the pickers 12_1 to 12_4 are inserted into the holes 25, 26, 27_1, and 27_2 (Step S2).

  As shown in FIG. 7A, the core 40 may be disposed at a position shifted from the place where the core is originally disposed (indicated by reference numeral 50). Here, as shown in FIG.7 (b), the diameter of each hole 45, 46, 27_1, 27_2 is larger than the diameter of the holding parts 14_1 to 14_4 (the contracted state) of each picker 12_1 to 12_4. small. For this reason, when the pickers 12_1 to 12_4 are lowered, the gripping portions 14_1 to 14_4 are inserted into the holes 45, 46, 27_1, and 27_2. At this time, since the position of the core 40 is shifted from the original position (indicated by reference numeral 50), the center position 41 of the positioning hole 45 of the core 40 in the xy plane is the center position of the positioning picker 12_1 in the xy plane. Deviation from 33.

  Next, the gripping part 14_1 of the positioning picker 12_1 inserted into the positioning hole 45 is expanded (step S3). As a result, as shown in FIG. 7C, the core 40 moves to the reference position in the xy plane, and the position of the positioning hole 45 of the core 40 in the xy plane is determined. In the case shown in FIG. 7C, since the cross-sectional shape of the positioning hole 45 is substantially square, the outer periphery of the expanded gripping portion 14_1 (circular in cross section) comes into contact with the four sides of the substantially square positioning hole 45. . Thereby, the position in the xy plane of the positioning hole 45 of the core 40 is determined.

  Next, the gripping portion 14_2 of the positioning picker 12_2 inserted into the positioning hole 46 in a state where the gripping portion 14_1 of the positioning picker 12_1 is inserted into the positioning hole 45 of the core 40 and the gripping portion 14_1 is inflated. Is expanded (step S4). As a result, as shown in FIG. 7D, the position in the rotational direction of the core 40 with the reference position (center position) 33 on the xy plane as the center axis can be determined. In FIG. 7D, the position of the core 20 in FIG. In this case, although the cross-sectional shape of the positioning hole 45 is substantially square, the cross-sectional shape of the expanded gripping portion 14_1 is circular, so that the core 40 can rotate around the positioning hole 45. Further, in this case, since the cross-sectional shape of the positioning hole 46 in the xy plane is substantially rectangular, the gripping portion 14_2 in the expanded state comes into contact with the two long sides of the substantially rectangular, so that the position of the core 40 in the rotational direction Can be determined.

  At this time, the pressure of the gripping portion 14_1 of the positioning picker 12_1 is adjusted so that the core 40 is rotatable about the positioning hole 45. (That is, make sure the pressure is not too high).

  Thereafter, the pressures of the gripping portions 14_1 and 14_2 of the positioning pickers 12_1 and 12_2 are increased to a predetermined pressure (step S5). Thereby, the position in the xy plane of the core 40 can be fixed. By such an operation, the core 40 (see FIG. 7A) that has shifted in the xy plane can be arranged and fixed at a position where it should be (see FIG. 7D).

  Moreover, as shown in FIG. 7, the cross-sectional shape in the xy plane of the positioning hole 46 is a substantially rectangular shape. Thus, even when the position between the positioning hole 45 and the positioning hole 46 is shifted, the positional shift is absorbed by making the cross-sectional shape of the positioning hole 46 on the xy plane substantially rectangular. Can do. In other words, the tolerance between the positioning hole 45 and the positioning hole 46 can be absorbed.

  In the above-described embodiment, the case where the core 20 includes the two positioning holes 25 and 26 has been described. However, in the present embodiment, only one positioning hole 25 may be provided. By providing the positioning hole 25, the core can be positioned in the xy plane in the same manner as described above. In this case, the position in the rotational direction of the core 20 cannot be corrected. However, when the positional displacement in the rotational direction of the core 20 is small, the structure having only the positioning hole 25 is sufficient. Can be corrected.

  Although the present invention has been described with reference to the above embodiment, the present invention is not limited only to the configuration of the above embodiment, and within the scope of the invention of the claims of the present application. It goes without saying that various modifications, corrections, and combinations that can be made by those skilled in the art are included.

DESCRIPTION OF SYMBOLS 1 Core gripping apparatus 10 Support part 12_1, 12_2 Positioning picker 12_3, 12_4 Grasping picker 14_1-14_4 Grasping part 20, 40 Core 21 Core main part 22 Skirting part 24_1-24_4 Cores 25, 26, 45, 46 Positioning hole 27_1, 27_2 Gripping hole

Claims (1)

A core gripping method for gripping the core by inflating and contracting gripping portions provided in each of the plurality of pickers into a plurality of holes formed in the core and expanding the gripping portion. ,
The core includes, as the plurality of holes, a positioning hole for determining a position of the core on a reference plane perpendicular to the lifting direction of the picker, and a gripping hole for gripping the core,
The cross-sectional shape of the positioning hole at the reference surface is a circle or a substantially square,
When gripping the core,
Inflating the gripping part of the positioning picker inserted in the positioning hole to determine the position of the core on the reference plane;
After determining the position of the core on the reference surface, the gripping part of a gripping picker inserted into a gripping hole for gripping the core is expanded to grip the core.
Core gripping method.

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