JP2865558B2 - Molded product sorting method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates is open-type after the injection molding, to a method Ru sorting the product and sprue runner of interest from the molded article to be taken out is removed from the mold.

[0002]

2. Description of the Related Art In injection molding, sprue and runners, which are unnecessary, are formed at the same time as an intended injection-molded product. Therefore, it is necessary to sort the molded product taken out of the mold into a product and a sprue / runner or, when a plurality of products are molded at the same time, the products themselves. Although this sorting operation can be performed manually, there are problems in productivity and cost. It is conceivable to save labor by using a robot.However, the robot itself is expensive, it requires sorting and removal time by the robot, the molding cycle becomes longer, and the robot must be adjusted according to the type of molded product. It does not necessarily contribute to the improvement of productivity, for example, when it becomes necessary.

[0003] Therefore, the sorting by performing multiple changing the mold opening-out position of the mold, i.e. to demolding one of the molded article in the middle position of the mold opening, the other in another intermediate position or mold opening completion position It has also been proposed to remove the molded product from the mold and sort the product (Japanese Patent Laid-Open No. 5-177677). In addition, as a method of sorting by changing the position to be removed, a three-plate mold having an intermediate plate is used. A product is inserted between the movable die and the intermediate plate, and a sprue and a die are inserted between the fixed die and the intermediate plate.
It has been proposed to sort runners by dropping them (Japanese Utility Model No. 4-20591).

[0004]

However, these methods of sorting after changing the position where the mold is released after opening the mold need to secure a sufficient mold opening distance to ensure the sorting of the molded products. Therefore, the size of the injection molding machine is increased, and an extra space is required. In addition, these require a special mold and a special mold control device. The present invention aims to provide a practical molded article <br/> sorting only method by simple means under these circumstances.

[0005]

Means for Solving the Problems As a result of intensive studies, the present inventor has found that by providing a time lag in the demolding of a molded product after opening the mold, the molded product can be reliably manufactured without a special mold or special mold control. The present inventors have found that they can be classified as follows, leading to the present invention. That is, according to the present invention, after the injection molding, the mold is opened, the first molded article is released from the mold and guided to a chute disposed immediately below the mold, and a swinging sorting provided in the chute is performed. After passing through a first discharge path formed by the plate, a predetermined time difference is provided and the sorting plate is rocked so as to form a second discharge path, and the second molded product is removed from the second mold by dropping. discharge path is passed through a further having a first and / or spiral fins disposed in the second discharging channel outlet
Two rotating pipes are arranged in parallel, and
It is a gist of the present invention to provide a method for sorting molded articles by a molded article separating apparatus for separating molded articles according to intervals .

[0006] The injection molding machine used in the present invention is not particularly limited, and the same applies to a mold comprising a fixed mold and a movable mold, and a mold clamping device therefor. Means for removing a molded article from a cavity after opening the mold. The device itself uses a known ejector pin. What is important in the present invention is to provide a time difference between the ejection of the molded product by the ejector pins after the mold is opened and the release of the molded product, and accordingly, the sorting plate in the shooter for receiving the molded product disposed immediately below the mold is shaken. To form two discharge paths alternatively, thereby separating the molded articles. By using the molded product sorting apparatus of the present invention, products and sprue / runner can be easily and reliably sorted. If there are a plurality of products, that is, if the target molded product is
In the case of the three types of products and sprue / runners, each molded product can be sorted by further arranging a suitable separating device at the outlet of the discharge path.

[0007]

According to the present invention, after the mold is opened, the first molded product which is released from the mold by the operation of the first ejector pin is guided to the shooter immediately below the mold and passes through the first discharge path formed by the sorting plate. Let it. The molding is performed by guiding the second molded product that is released from the mold by the operation of the second ejector pin provided with a predetermined time difference to the second discharge path formed by swinging the sorting plate so as to interlock with the operation. Products can be sorted.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. Reference Example 1 FIG. 1 is a sectional explanatory view of a horizontal injection molding machine. In FIG.
Reference numeral 1 denotes a gantry on which an injection device 2, a mold device 3, and a mold clamping device 4 are placed. The injection device 2 includes a hopper 5 for storing a molding resin, a nozzle 11 for injecting the molding resin into a mold, and a heating cylinder 6 for melting the resin. Mold device 3
Is composed of a fixed platen 7 and a movable platen 8. The fixed die 9 and the movable die 10 of the molds are respectively mounted, and the movable platen 8 is moved with respect to the fixed platen 7 by the direct pressure type cylinder of the mold clamping device 4 to perform mold clamping and Open the mold. Further, it also has a function of operating an ejector rod 12, which will be described later, not shown in FIG. 1 by hydraulic pressure.

FIG. 2 is an explanatory view of the movable mold 10 and the fixed mold 9. As shown in FIG.
3, 14, and 15 are provided. The resin is injected into the mold through the heating cylinder 6 and the nozzle 11 by the injection device 2 to form the products A and A ′ and the sprue runner. The mold is opened after the injection molding, and the ejector rod 12 is actuated in conjunction with the mold opening to push the ejector front plate 17 on which the ejector pins are assembled and the ejector rear plate 16 which is bolted, thereby forming the movable mold 18.
The molded products A, A 'and the sprue runner B are released from the mold (FIG. 3). The products A and A 'fall to the shooter 20 disposed immediately below the mold. As shown in FIG. 4, a sorting plate 21 which swings so as to form two discharge paths and a partition plate 22 which forms one discharge path are provided in the shooter. The swinging of the sorting plate 21 is caused to occur after a preset time elapses in consideration of the drop passage time of the products A and A 'by the operation of the timer after the mold is opened.

More specifically, after the mold is opened, the molded article is released from the mold 18 by the first ejector pins 13 and 15 and the second ejector pin as described above. The products A and A 'protruded by the parts 13 and 15 fall into the shooter 20 as they are, are guided to the first discharge path (FIG. 5A), and are stored in the storage box 24. The sprue runner protruding from the second ejector pin 14 is held at the tip of the ejector pin as shown in FIG. On the other hand, after the mold is opened, the timer is operated, and after a predetermined time, the sorting plate 2 in the shooter 20 is opened.
1 swings by the operation of a rotary actuator (not shown) to form a second discharge path (FIG. 5B). When the ejector rod 12 is retracted, the ejector plate 17 is pushed back by the return spring 19, and the ejector pins 13, 14, 15 are returned to their original positions. The sprue / runner engages with the movable mold 18, detaches from the ejector pin 14 returned by the return spring 19, falls onto the shooter 20, and forms the second discharge formed by the swing of the sorting plate 21. It is stored in the storage box 26 through the path (FIG. 5B). The holding of the molded product by the tip of the ejector pin is possible for the molded product as well as the sprue runner.

REFERENCE EXAMPLE 2 This reference example differs from Reference Example 1 in the order in which the molded articles are discharged. First, the sprue / runner D is discharged first, and then the products C,
This is an example of discharging C '. FIG. 6 is an explanatory view of the movable mold 10 and the fixed mold 9 similar to FIG. The only difference is that the product ejector pins 31 and 33 perform a two-stage projecting operation. That is, FIG. 7 showing details of arrows (2) and (3) in FIG.
(The ejector pin 31 is not shown) will be described.

As in Reference Example 1, a resin is injected into a mold to form molded products C and C ′ and a sprue runner D. After cooling, open the mold. At the end of the mold opening, the ejector rod 12 is operated. Each of the ejector pins 31 and 33 has a support pin 35 for a two-step protrusion operation provided in a support hole 36 for adjusting the amount of step protrusion. The total length of the support pins 35 is equal to the thickness of the ejector rear plate 37, and supports the ejector pins 33 between the movable mounting plate 40 and the ejector pins 33 so that the ejector pins 33 do not return due to the resin pressure during molding. The support hole 36 has a diameter such that the ejector pin 33 and the support pin 35 can slide, and a difference in two-stage protrusion is generated at the depth. Step difference = (support hole)-(support pin neck length)
Is represented by The first ejector pins 34 protrude with the movement of the ejector rear plate 37 by being pushed by the ejector rod 12, and the sprue / runner D is dropped from the movable mother die 38 as a first molded product (FIG. 8).
However, at this time, the second ejector pin 33 has not yet been protruded because the movement amount of the ejector rod 12 is smaller than the step amount. This protrusion amount is set as the first protrusion amount. The first molded product that has been pushed out and dropped passes through one discharge path. When the first ejection is completed and the ejector rod returns to the original position, the timer is operated, and the sorting plate 21 is swung to close the one path and form the other path.

Next, the ejector rod 12 is operated again to advance the ejector pin for the second protrusion.
The second protrusion amount is set so as to exceed the step amount as shown in FIG. By doing so, support pin 3
Reference numeral 5 denotes the bottom of the support hole, the second ejector pin 33 is protruded, the product C ′ is released from the movable mother die 38, and the sprue / runner formed by the swing of the sorting plate 21 is discharged. It is led to a different route from the route. The ejector pins 31 (not shown in FIGS. 7 to 9) operate exactly the same as the ejector pins 33, so that the molded product C can be dropped simultaneously with C ′. The two-step projecting operation can be performed only on one of the ejector pins 31 and 33. In this case, the product C or C 'together with the sprue runner will fall onto the shooter 20, and further separation as described later will be required.

Embodiment 1 In Reference Examples 1 and 2, the case where there are two types of molded articles to be sorted has been described. In this example, the case where there are three types of molded articles will be described. In this case, sorting can be performed by providing another molded article separating device at the outlet of the two discharge paths. The separation device is not particularly limited, but preferably has a small size and a simple structure. One example is shown in FIG. FIG. 10 is a perspective view of the separation device 25, and FIG. This separating device is mainly composed of nylon pipes 27 and 28 having spiral fins as shown in FIG. 12, and the distance between 27 and 28 can be adjusted by moving the nylon pipe 28 by a handle 29. (FIGS. 13a and 13b). Nylon pipe 27
Can be sent to the storage box 26 by rotating outwardly with motor rollers stored respectively as right-handed and 28 left-handed. Anything smaller than the gap between the pipes is put into the storage box 30. Therefore, two types of molded products having different sizes can be further sorted by using the separating device.

[0015]

As described above, according to the present invention, molded articles can be efficiently and reliably sorted by a simple means of providing a time difference in demolding of molded articles using a conventional injection molding machine and a mold. be able to.

[Brief description of the drawings]

FIG. 1 is a sectional explanatory view of a horizontal injection molding machine,

FIG. 2 is an explanatory view of a movable mold 10 and a fixed mold 9;

FIG. 3 is an explanatory view of removal of a molded product by an ejector pin;

FIG. 4 is an explanatory view of a molded article sorting apparatus of the present invention,

FIG. 5 is an explanatory view of formation of two molded article discharge paths by swinging of a sorting plate in the present invention;

FIG. 6 is an explanatory view of a movable type and a fixed type different from FIG. 2,

FIG. 7 is an explanatory view of an ejector pin capable of performing a two-stage protrusion operation,

FIG. 8 is an explanatory diagram of an operation of an ejector pin in a first stage of a two-stage protrusion operation,

FIG. 9 is an explanatory view of the operation of the ejector pin in the second stage of the two-stage protrusion operation;

FIG. 10 is an explanatory view of a separation device used as needed in the present invention,

11 is an explanatory side view of the separation device of FIG. 10,

FIG. 12 is an explanatory view of a roller of the separation device;

FIG. 13 is an explanatory view of an interval adjusting device for the roller.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B29C 45 / 40,45 / 17 B07B 1/14-1/15

Claims (1)

(57) [Claims] After the injection molding, the mold is opened, and the first molded product is dropped from the mold and guided to a chute disposed immediately below the mold, and a swinging sorting plate provided in the chute is provided. Then, the sorting plate is swung so as to form a second discharge path with a predetermined time difference provided between the first discharge path and the second molded product, and the second molded product is dropped and removed from the second discharge path. passed through a discharge path, two more rotation with the first and / or spiral fins disposed in the second discharging channel outlet
Pipes are arranged in parallel, and the
A method of sorting molded products using a molded product separation device that separates molded products.