JP2000229325A - In-mold detachable stamping apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform stable stop of turning of a screw, operability of an index and accurate and easy positioning by disposing a base end of an index threaded part above an upper end of an engaging groove in the state that upper surfaces of an index and a display outer shell are disposed in plane. SOLUTION: A base end 42a of a threaded part 42 of an index 4 is disposed above an upper end 34a of an engaging groove 34 in the state that an upper surface of the index 41 and an upper surface of a display outer shell 3 are disposed in plane. A nut 6 cannot move upward above the upper end 34a of the groove 34 so as not to arrive at the end 42a of the part 42, and hence an intrusion of the nut 6 into the base end 42a can be prevented. A plurality of engaging grooves 31a to be partly engaged with a sphere of a positioning member of an index base 41b are circumferentially continuously formed at an equal interval on an upper step 31 of the shell 3. When a spring is compressed as the index 4 is rotated, a sphere is intruded into the adjacent groove 31a. Thus, the index 4 can be accurately, easily positioned in response to a display position of the shell 3, thereby providing excellent attaching and detaching operability of the index 4 and stabilizing stopping of turning of a screw.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engraving device for imprinting a mark on the surface of a molded product during molding of a mold, and more particularly, to easily perform the work of exchanging the imprint without causing irregularities on the surface of the molded product. The present invention relates to an in-mold detachable engraving device which has good operability of attaching and detaching operation of an index body, and can accurately and easily position the index body in accordance with a mark position of an outer shell.

[0002]

2. Description of the Related Art A molded product usually has a manufacturing date, a lot number, a product number, etc. displayed on a surface thereof, and these displays are used for investigating a cause of a defective product and managing inventory. Is going. These indications are obtained by inserting a display body provided with a stamped display part on the inner surface side of a molding die in a detachable manner and performing molding with the inserted state, so that the engraved content of the display body remains on the surface of the molded product as it is. It is designed to be stamped.

As a conventional marking device of this type, there is, for example, a marking device as shown in FIG. The marking device (A) shown in FIG. 4 is a display outer shell (B) fitted into a mold.
An index body (C) having a large-diameter portion (c1) and a small-diameter portion (c2) and fitted into the display shell (B), and an O-ring (D) attached to the index body (C). A display portion made of numerals or the like is formed on a surface of the display outer shell (B) and the indicator (C) facing the inside of the mold. The marking device (A) is used by being inserted into a mold so that the display portions of the display outer shell (B) and the indicator (C) face the inner surface of the mold. Displayed outer shell (B)
Is configured to display "month" and "year" with the index body (C), and it is sufficient to replace only the index body (C) when the year changes, but the marking device ( A) The index body (C) cannot be removed unless the entire body is removed from the mold, which is very troublesome and causes a reduction in work efficiency.

In view of such a drawback, there is a stamping device as shown in FIG. 5, which can replace only the indicator without removing the entire stamping device from the mold. FIG.
The engraving device (A) shown has an outer shell (E) fitted into the mold, an index portion (f1) facing the inner surface of the mold, and a screw portion (f).
2) The indicator body (F) which consists of the outer shell body (E)
It is composed of The outer shell (E) has an inner diameter of two steps, and a screw groove is threaded in the lower step (e1), and the screw part (f2) of the indicator (F) is screwed into this screw groove. Have been. Then, the lower surface of the index portion (f1) and the outer shell (E)
A spring (G) is interposed between the upper steps (e2) of the
By rotating the indicator (F) with a screwdriver or the like to remove the screw from the outer shell (E), only the indicator (F) can be removed from the mold. However, in the marking device shown in FIG. 5, the indicator (F)
Is always urged toward the inside of the mold by the spring (H), so that the indicator (F) tends to protrude from the outer shell (E) on the inner surface of the mold. There is a problem that the outer shell (E) cannot be kept at the same level, and irregularities occur on the surface of the molded product, so that a uniform molded surface cannot be obtained.

[0005]

In view of the above situation, the present inventor disclosed in Japanese Patent Application Laid-Open No. Hei 10-34671 that a spring force is applied to an indicator body in a direction such that its surface does not protrude from the outer shell body surface. An energized in-mold detachable engraving device is proposed. Since this marking device can keep the indicator body and the outer shell flush, there was no unevenness on the surface of the molded product, but the following problems existed. . That is, in this engraving device, in order to prevent the nut screwed into the screw portion of the indicator body from rising with the clockwise rotation of the indicator body during use,
Since the threaded portion and the nut of the indicator were formed in a reverse screw (left-handed thread), the operability of attaching and detaching the indicator was poor. Further, in the configuration in which a detent projection is provided on the outer peripheral surface of the screw and the projection is engaged with the engagement recess formed on the inner surface of the outer shell, only one projection is provided. Sometimes stopped functioning stably. In addition, since the lid attached to the lowermost surface of the outer shell had a disk shape without holes, it was difficult to perform the attaching / detaching operation of the lid. Further, it has been difficult to accurately and easily position the indicator according to the display position of the outer shell. The present inventors have conducted intensive research to solve the above problems,
The present invention has been completed.

[0006]

The present invention employs the following means in order to solve the above-mentioned problems of the prior art. Claim 1
According to the described invention, a substantially cylindrical display shell fitted into a molding die, and an index body fitted into the display shell and capable of angular displacement about an axis are engraved on both surfaces. A marking device in which a portion is formed, wherein the indicator body includes an indicator portion facing the inner surface of the mold and a screw portion extending from the indicator portion, and the inner diameter of the display outer shell is the indicator body. A small-diameter upper portion where the index portion is located when inserted,
A large-diameter lower part in which the screw part is located, a lid is screwed to the lowermost part of the lower part, and a nut is screwed to the screw part of the indicator, A spring is interposed between the display shell and the upper surface of the lower portion of the display shell, and a downward force is applied to the indicator by the spring. A plurality of protrusions are provided on the outer periphery of the nut. At the same time, an engagement groove engageable with the projection is formed in the lower portion of the display outer shell in the axial direction, and in a state where the upper surface of the indicator portion and the upper surface of the display outer shell are flush with each other, The in-mold detachable marking device is characterized in that a base end of a threaded portion of the indicator is located above an upper end of the engagement groove.

According to a second aspect of the present invention, there is provided the in-mold removable marking device according to the first aspect, wherein a square hole is provided in the center of the lid. In the invention according to the third aspect, a positioning member including an elastic body extending radially outward and a sphere attached to a tip end of the elastic body is provided at the index portion of the index body, and the indicator is provided. 3. A plurality of insertion grooves into which a part of a sphere of a positioning member is inserted into an upper portion of the outer shell are formed continuously and at equal intervals along a circumferential direction. In-mold removable marking device.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an in-mold detachable marking device according to the present invention will be described below with reference to the drawings. FIG. 1 is a sectional view of an in-mold detachable engraving device (1) according to the present invention, and FIG. 2 is a partially cutaway exploded perspective view thereof.
An in-mold detachable engraving device (1) according to the present invention comprises a substantially cylindrical display outer shell (3) fitted into a molding die, and a corner around the axis in the display outer shell (3). And an indicator (4) that is displaceably fitted.

FIG. 3 is a sectional view showing an example in which the in-mold detachable marking device (1) is attached to a mold. The molding die (2) shown in FIG. 3 includes a fixed die (21) having an injection port (23),
The movable mold (22) comes into contact with and separates from the fixed mold (21), and a cavity (24) is formed between the fixed mold (21) and the movable mold (22). The removable marking device (1) is provided with a cavity (2) in a movable mold (22).
Installed facing 4).

[0010] On the surface of the display outer shell (3) (the surface facing the inner surface of the mold), a numeral "1" representing the month at equal intervals in the circumferential direction,
An engraved display portion consisting of “2”, “3”,..., “12” is formed, and a numeral representing the year (“99” in the illustrated example) and a display shell are provided on the surface of the indicator (4). Arrow-shaped index (43) indicating the month display provided on the surface of the body (3)
Is formed, and the year and month can be simultaneously displayed by the year display displayed on the index body (4) and the month display pointed by the index (43). The index (43) is a groove that can be rotated by a driver.

The indicator (4) comprises an indicator (41) and a screw (42) extending from the indicator (41), and the surface of the indicator (41) is a mold (2). A disc-shaped index surface portion (41a) facing the inner surface and this index surface portion (41a)
The index base portion (41b) having a smaller diameter than the index surface portion formed at the lower part of (a)). The index base (41b) is provided with a positioning member (9) including a spring (91) extending radially outward and a sphere (92) attached to the tip of the spring (91). ing. The direction of the arrow of the index (43) matches the direction in which the positioning member (9) extends. The screw portion (42) is a forward thread (right-hand thread).

The inner diameter of the display outer shell (3) is determined by the indicator (4).
Is provided with a small-diameter upper portion (31) where the index portion (41) is located when the is inserted, and a large-diameter lower portion (32) where the screw portion (42) is located, and the lower portion (32). A lid (5) is screwed to the lowermost portion. The inner diameter of the lower portion (32) is such that the inner diameter of the female screw portion (33) to which the lid (5) is screwed is formed larger than the inner diameter of the other portion, and the length of the female screw portion is the thickness of the lid. Has been equal to.

A nut (6) is screwed to the lower end of the indicator (4), and the nut (6) has an outer diameter substantially equal to the inner diameter of the lower portion (32). A spring (7) is interposed between the nut (6) and the upper surface of the lower portion (32) of the display shell (3), and the spring (7) faces the indicator (4) downward. , That is, a force acting so that the surface of the indicator (4) does not protrude from the surface of the display shell (3). Therefore, the surfaces of the display outer shell (3) and the indicator (4) are completely flush with each other, and a uniform molded surface can be obtained without unevenness on the surface of the molded product. In addition, when the year changes, the indicator (4) is rotated with a screwdriver and unscrewed from the nut (6), so that only the indicator (4) is removed and replaced without disassembling the mold. The replacement work is easy and the work efficiency is excellent.

A plurality (three in the illustrated example) of semicircular projections (61) are provided on the outer periphery of the nut (6), and a lower portion (32) of the display shell (3) is provided on the lower portion (32). These projections (6
An engagement groove (34) having a semicircular cross section in which 1) can be engaged is formed in the axial direction. In the present invention, the projection (61)
Is not particularly limited as long as it is plural, and may be two, four, or five or more. Further, the number of the engagement grooves (34) is provided as the number of the protrusions (61). As described above, by using a plurality of protrusions (61), the function of preventing the rotation of the nut (6) can be stably exhibited.

In the in-mold detachable marking device (1) according to the present invention, as shown in FIG. 1, when the upper surface of the index portion (41) and the upper surface of the display shell (3) are flush with each other, The proximal end (42a) of the screw portion (42) of the indicator (4) is configured to be located higher than the upper end (34a) of the engagement groove (34). As a result, the nut (6) cannot move above the upper end portion (34a) of the engagement groove (34), and the nut (6) cannot move to the proximal end portion (4) of the screw portion (42).
2a), it is possible to prevent the nut (6) from digging into the base end (42a). This eliminates the necessity of forming the screw portion and the nut of the indicator body into a reverse screw (left-handed screw) as in the related art.
The operability of the attaching and detaching operation of the indicator is excellent.

A square hole (51) is provided at the center of the lid (5). By inserting a wrench or the like into the square hole (51), the lid (5) can be easily rotated and tightened. It is possible. In the illustrated example, a square hole (51)
Is a square, but may be a hexagon or the like. Further, a hole that does not reach the bottom surface of the lid (5) may be used instead of the through hole. It is preferable that the inner diameter of the square hole (51) is formed larger than the outer diameter of the screw portion (42) of the indicator (4). The reason is that the inner diameter of the square hole (51) is formed to be larger than the outer diameter of the screw portion (42) of the indicator (4), as shown in FIG. ) Can be inserted into the square hole (51), and the length of the screw portion (42) can be increased. Thus, when the indicator (4) is rotated during use, the number of rotations until the nut (6) and the screw (42) are disengaged increases, and the screw and the nut of the indicator are removed. Even in the case of forming a forward thread (right-hand thread), the nut (6) and the threaded portion (42) do not come off from each other during use.

In the upper part (31) of the display shell (3),
A plurality of fitting grooves (31a) into which a part of the sphere (92) of the positioning member (9) provided on the index base (41b) is fitted.
Are formed continuously and at equal intervals along the circumferential direction. The number of the fitting grooves (31a) may be appropriately set depending on how many times the index body (4) is to be rotated. For example, as shown in the illustrated example, the index body (4) is rotated every month. In the case of a configuration, the number may be 12. Sphere (92)
Is always urged radially outward by a spring (91), and in a normal state, the sphere (92) has one fitting groove (3).
1a), but when the indicator (4) is rotated, the spring (91) shrinks, causing the sphere (9) to shrink.
2) comes into the adjacent fitting groove (31a).
Thus, the indicator (4) can be accurately and easily positioned according to the display position of the display outer shell (3).

In the in-mold detachable marking device (1) according to the present invention, the display outer shell (3) and the indicator (4).
Is not limited to the illustrated example. For example, the indicator (4) is configured to display the month and the display shell (3) is configured to display the day, or the lot number or the product number is displayed as a whole. Any configuration may be used as long as the display can be used for a long time by replacing only the indicator (4).

[0019]

As described above, according to the first aspect of the present invention, there is provided a substantially cylindrical display outer shell fitted into a molding die, and an angular displacement about an axis inserted into the display outer shell. A marking device comprising a possible indicator, and a marking display portion formed on both surfaces, wherein the indicator comprises an indicator facing the inner surface of the mold and a screw extending from the indicator. The inner diameter of the display outer shell includes an upper portion of a small diameter where the index portion is located when the indicator is inserted, and a lower portion of a large diameter where the screw portion is located. A lid is screwed to the lowermost part of the portion, and a nut is screwed to the threaded portion of the indicator, and a spring is interposed between the nut and the upper surface of the lower portion of the display shell. A downward force is applied to the indicator by the spring, and a plurality of protrusions are formed on the outer periphery of the nut. An engagement groove engageable with the projection is formed in the lower part of the display outer shell in the axial direction, and the upper surface of the indicator and the upper surface of the display outer shell are flush with each other. In this state, since the proximal end of the threaded portion of the indicator is located above the upper end of the engagement groove, the in-mold removable marking device is characterized in that When rotated, the nut can be prevented from digging into the screw base end of the indicator, and it is not necessary to form the screw and nut of the indicator into a reverse screw. It will be excellent in property. In addition, the nut rotation preventing function is stably exhibited.

According to a second aspect of the present invention, there is provided the in-mold removable marking device according to the first aspect, wherein a square hole is provided at the center of the lid body. By inserting the cover, it is possible to easily rotate and tighten the lid, and by forming the inner diameter of the square hole larger than the outer diameter of the threaded portion of the indicator, the screw and nut of the indicator are forward screwed. Even when formed, the nut and the threaded portion do not come off during use.

According to a third aspect of the present invention, a positioning member comprising an elastic body extending radially outward and a sphere attached to the tip of the elastic body is provided at the index portion of the index body. 2. A plurality of insertion grooves into which a part of a sphere of a positioning member is inserted into an upper step portion of the display outer shell are formed continuously and at equal intervals along a circumferential direction. Alternatively, since the in-mold detachable engraving device according to Item 2, the indicator can be accurately and easily positioned according to the display position of the display outer shell.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a preferred embodiment of an in-mold detachable marking device according to the present invention.

FIG. 2 is a partially cutaway exploded perspective view showing a preferred embodiment of the in-mold removable marking device according to the present invention.

FIG. 3 is a cross-sectional view showing an example in which the in-mold detachable marking device according to the present invention is attached to a mold.

FIG. 4 is an exploded perspective view showing an example of a conventional marking device.

FIG. 5 is a sectional view showing an example of a conventional marking device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 In-mold detachable marking device 2 Die 3 Display outer shell 31 Upper part 32 Lower part 34 Engagement groove 34a Upper end part of engagement groove 4 Indexer 41 Indexer 42 Screw 42a Base end 43 Indicator 5 Lid 5 51 square hole 6 nut 61 protrusion 7 spring 9 positioning member 91 spring 92 sphere

Claims (3)

[Claims] 1. A substantially cylindrical display outer shell fitted into a molding die, and an indicator inserted into the display outer shell and capable of being angularly displaced about an axis, and engraved on both surfaces. A marking device in which a portion is formed, wherein the indicator body includes an indicator portion facing the inner surface of the mold and a screw portion extending from the indicator portion, and the inner diameter of the display outer shell is the indicator body. It has a small-diameter upper part where the index part is located when inserted, and a large-diameter lower part where the screw part is located, and a lid is screwed to the lowermost part of the lower part. At the same time, a nut is screwed into the screw portion of the indicator body, and a spring is interposed between the nut and the upper surface of the lower portion of the display shell, and a downward force is applied to the indicator body by the spring. A plurality of projections are provided on the outer periphery of the nut,
An engagement groove engageable with the projection is formed in a lower portion of the display outer shell in the axial direction, and the index is provided when the upper surface of the indicator is flush with the upper surface of the display outer shell. An in-mold detachable marking device, wherein a base end of a thread portion of a body is located above an upper end of the engagement groove. 2. The in-mold removable marking device according to claim 1, wherein a square hole is provided at the center of the lid. 3. A positioning member comprising an elastic body extending radially outward and a sphere attached to the tip of the elastic body is provided at the indicator portion of the indicator body, and the display shell body is provided. 3. A mold according to claim 1, wherein a plurality of insertion grooves into which a part of the sphere of the positioning member is inserted are formed continuously and at equal intervals along the circumferential direction in the upper step portion. Detachable marking device.