JPH0985422A - Device for correcting shape of cast product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the producing cost of a cast product by simplifying the following treatment after casting the cast product. SOLUTION: In a metallic mold for trimming TM, a shape correcting device K applying the shape correction to a case member 3 is attached. Then, whether the shape error in the case member 3 exists or not, is automatically detected with a strain detecting mechanism 13 in a trimming process, and if the shape error exists, a strain correcting bar 16 is lowered with a hydraulic cylinder 15 just after trimming to press the case member 3 by this bar, and this shape error is corrected. Thus, the following treatment process of the case member 3 is simplified and the producing cost of the case member 3 is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shape correcting device for a cast product, which is attached to a die for trimming a cast product and corrects the shape error in the trimming process when the cast product is accompanied by a shape error. It is about.

[0002]

2. Description of the Related Art Generally, a cast product is obtained by injecting a molten metal (molten metal) into a cavity of a predetermined shape formed inside a mold, cooling and solidifying the molten metal in the cavity, and then removing the mold. It is manufactured by the procedure of taking out a casting. However, the cast product thus taken out is accompanied by unnecessary deposits such as a sprue and a burr (casting). Therefore, for such cast products,
Usually, after casting, first use a trimming mold etc.,
Trimming (such as a chipping process or a cutting process) of adhering matters such as a sprue and a burr (for example, JP-A-4-1873).
64, JP-A-4-1629771, etc.).

By the way, in principle, such a cast product should be formed in a shape corresponding to the cavity (inverted shape), that is, a predetermined shape engraved in advance, but in reality, a shape error may occur. Many. That is, when the molten metal in the cavity is cooled and solidified, it slightly contracts (for example, about 6/1000 in an aluminum alloy), which may cause distortion (or deformation) in the cast product. Further, the cast product may be distorted due to variations in the release agent applied to the mold. In addition, local forces exerted on the casting when removing the casting from the mold can cause distortion.

Such a shape error (distortion or deformation) is likely to occur in a case-shaped cast product having a locally different wall thickness, such as an automobile transmission case or differential case (for example, at a rate of about 1/10). Shape error occurs). Therefore, in general, for cast products, especially for case-shaped cast products, the shape correction processing is performed on the cast products with shape error after inspecting the presence or absence of the shape error by hand. .

[0005]

As described above, in the production of cast products, particularly case-shaped cast products, after casting, trimming of deposits such as sprues and burrs, shape error inspection of cast products, Since various post-treatments such as a shape correction process for a certain cast product must be performed, there is a problem in that the productivity thereof becomes low and the production cost of the cast product becomes high.

The present invention has been made in order to solve the above-mentioned conventional problems, and it is possible to simplify the post-treatment of a cast product after casting, thereby reducing the manufacturing cost of the cast product. The problem to be solved is to obtain the means to do so.

[0007]

A first aspect of the present invention, which has been made to solve the above-mentioned problems, is a shape correcting device for a cast product, which comprises a fixed die for holding the cast product and the cast product. A movable die for trimming is provided and is attached to the movable die, and a shape correction member is provided to correct the shape of the cast product in a trimming step if the cast product has a shape error. It is characterized by being present.

In the shape correction device for a cast product according to the first aspect, the shape correction member attached to the movable mold is used for the cast product in the trimming step, that is, at the same time as or immediately after the trimming operation of the movable mold. Since the shape correction is performed by using the shape correction process, it is not necessary to separately provide a shape correction process for the cast product. For this reason, the post-treatment of the cast product is simplified, which in turn reduces the manufacturing cost of the cast product. If the cast product is not accompanied by a shape error, it goes without saying that the shape is not corrected.

According to a second aspect of the present invention, in the shape correcting device for a cast product according to the first aspect of the present invention, the shape correcting member is a rod-shaped member fixed to the movable die,
At the same time as the movable type trimming operation, the cast product is pressed to correct the shape.

In the cast product shape correcting apparatus according to the second aspect, basically, the same operation and effect as in the cast product shape correcting apparatus according to the first aspect of the present invention can be obtained. . Further, at the same time when the movable die performs the trimming operation, the rod-shaped member presses the cast product to correct its shape. According to this structure, since the rod-shaped member has a very simple structure, the manufacturing cost of the shape correction device is reduced, and the manufacturing cost of the cast product is further reduced.

According to a third aspect of the present invention, in the shape correcting device for a cast product according to the first aspect of the present invention, the shape correcting member is a rod-like member capable of advancing and retreating with respect to the cast product. After the trimming operation of the movable die, the shape of the cast product is corrected by advancing toward the cast product to press the cast product.

In the cast product shape correcting apparatus according to the third aspect, basically, the same operation and effect as in the cast product shape correcting apparatus according to the first aspect of the present invention can be obtained. . Furthermore, since the shape is corrected by pressing the cast member by advancing the rod-shaped member after trimming, the operation of the rod-shaped member can be made to have a desired pressing characteristic. Therefore, the shape correction accuracy of the cast product is improved,
As a result, the quality of the cast product is improved.

A fourth aspect of the present invention is a shape correction device for a cast product according to the third aspect of the present invention, which is attached to the fixed mold and detects a shape error for detecting the presence or absence of a shape error of the cast product. Means and shape correction member control means for correcting the shape error of the cast product when the shape error detection device detects that the cast product has a shape error. It is characterized by.

In the cast product shape correcting apparatus according to the fourth aspect, basically, the same action and effect as in the cast product shape correcting apparatus according to the third aspect of the present invention can be obtained. . Furthermore, the presence or absence of shape error in the cast product is automatically detected, and the shape correction is automatically applied to the cast product with the form error, which further simplifies the post-processing of the cast product. It Therefore, the manufacturing cost of the cast product is further reduced.

A fifth aspect of the present invention is the shape correcting device for a cast product according to any one of the second to fourth aspects of the present invention, wherein the cast product is fixed to the movable die during trimming. A pressing member for pressing and fixing to the mold is provided, and the shape correcting member is arranged so as to penetrate the pressing member.

In the shape correcting device for a cast product according to the fifth aspect, basically, the shape correcting device for a cast product according to any one of the second to fourth aspects of the present invention is used. Similar actions and effects can be obtained. Further, since the bar-shaped member is arranged so as to penetrate the pressing member, the bar-shaped member can be easily arranged or laid out. Therefore, the manufacturing cost of the shape correction device is reduced, and the manufacturing cost of the cast product is further reduced.

According to a sixth aspect of the present invention, in the shape correction device for a cast product according to any one of the second to fifth aspects of the present invention, the movable die is arranged on the upper side, and the fixed die is It is arranged on the lower side, and is characterized in that a concave portion of a predetermined depth is provided at the upper end of the fixed mold below the shape correction member.

In the shape correcting device for a cast product according to the sixth aspect, basically, the shape correcting device for a cast product according to any one of the second to fifth aspects of the present invention is used. Similar actions and effects can be obtained. Further, in this shape correction device, the shape is corrected by moving the rod-shaped member downward to press the cast product downward. And
Since the recess is provided in the upper end of the fixed mold below the shape correction member, the cast product can be sufficiently deformed downward beyond the upper end surface of the fixed mold (to the inside of the recess), so that the shape correction accuracy can be improved. Is further enhanced, and the quality of cast products is further enhanced.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be specifically described below. As shown in FIG. 1, a trimming die TM for trimming a sprue, burr, etc. of a cast product,
A fixed mold F arranged on the lower side and a movable mold M arranged on the upper side are provided. Here, the fixed die F is fixed on a fixed portion such as a floor (not shown), while the movable die M can move in the vertical direction.

The fixed mold F is provided with a fixed side mounting plate 1 and a base portion 2 fixed to the upper end of the fixed side mounting plate 1.
A case member 3 which is a cast product is formed on the upper end surface 2b of the base portion 2.
(Eg, transmission case). The case member 3 is positioned by a product setting guide 4 attached to the upper end surface 2b of the base 2. Here, the case member 3 is manufactured by casting, but since the thickness is locally different, a shape error is relatively likely to occur during casting or removal. Most of the shape errors occurring in the case member 3 are outward (or upward in the arrangement state in FIG. 1) distortion or deformation in the curved surface portion 3a having a relatively thin wall thickness. Therefore, when the case member 3 is accompanied by a shape error, the tip portion 3b of the case member 3 is in a state of floating above the upper end surface 2b of the base portion 2 (FIG. 2).
reference).

In the movable mold M, a movable side mounting plate 5 which is vertically moved by an elevating mechanism (not shown), and a cutting blade 7 fixed to the lower end portion of the movable side mounting plate 5 and at the tip (lower end) thereof. And a cushion plate 8 (pressing member) for pressing and fixing the case member 3 at the time of trimming. Further, between the cushion plate 8 and the trimming member 6, a spring 9 having a relatively strong biasing force (for example, 50 kgf) that biases the cushion plate 8 downward during trimming is provided.

When trimming the case member 3, the case member 3 is placed at a predetermined position on the upper end surface 2b of the base 2 of the fixed mold F, and then the movable mold M is lowered. At this time, first, the cushion plate 8 contacts the upper end of the case member 3. When the movable die M further descends, the cushion plate 8 does not descend even though the trimming member 6 descends.
Is compressed, and the cushion plate 8 is pressed downward by the relatively strong biasing force of the spring 9 that is generated. Thus, the case member 3 is pressed and fixed to the upper surface of the base 2 by the cushion plate 8. Further, when the movable die M descends, the cutting edge 7 of the trimming member 6 causes the gate 10 attached to the case member 3 and the vacuum passage mark 11,
Deposits such as burrs (illustrated) are trimmed (cut off). Here, the vacuum passage mark 11 is a solidification of the molten metal that has flowed into the vacuum passage for evacuating the inside of the cavity during casting. Thus, the deposits on the case member 3, which is a cast product, are trimmed (removed).

By the way, the trimming die TM is provided with a shape correcting device K for correcting a shape error (distortion or deformation) generated in the case member 3 during casting. K will be described.
The shape correction device K is attached to each fixed mold F,
A strain detecting mechanism 13 (shape error detecting means) for detecting whether or not the case member 3 is accompanied by a shape error, and whether or not the case member 3 is arranged at the correct position on the upper end surface 2b of the base portion 2. Case member position detection mechanism 14 for detecting whether
Are provided.

Further, the shape correction device K has a hydraulic cylinder 15 fixed to the movable die M, and a distortion correction rod 16 vertically moved (advanced and retracted) by the hydraulic cylinder 15.
(Shape correcting member or rod-shaped member). The distortion correction rod 16 is arranged so as to penetrate the cushion plate 8, and thereby the shape correction device K
Is being made compact. Here, when the hydraulic pressure is supplied from the hydraulic mechanism 18 to the first oil chamber (not shown) in the hydraulic cylinder 15 through the hydraulic pipe 17, the distortion correcting rod 16 is pushed downward by the hydraulic pressure (advance), On the other hand, when the hydraulic pressure is supplied from the hydraulic mechanism 18 to the second hydraulic pressure (not shown) in the hydraulic cylinder 15 through the hydraulic pipe 17, the strain correction rod 16 is pulled back upward by the hydraulic pressure ( Move out). The distortion correction rod 1
The 6 may be pulled back by the return spring instead of the hydraulic pressure. Further, the trimming die TM is provided with a controller 19 (including shape correction member control means),
The controller 19 switches the hydraulic pressure supply / discharge path of the hydraulic mechanism 18, and the hydraulic cylinder 15 and thus the strain correction rod 1 is changed.
6 is controlled. In addition, below the distortion correction rod 16, at the upper end of the base portion 2 of the fixed mold F,
A recess 12 having a predetermined depth is provided.

As shown in FIG. 2, the strain detecting mechanism 13 has a strain detecting rod 22 fitted in a vertical hole 21 formed in the base 2, and the strain detecting rod 22 is relatively weak. There is provided a biasing spring 23 that constantly biases upward with a biasing force (at least a biasing force weaker than the spring 9). A cushion bolt 24 is provided to stabilize the posture of the biasing spring 23.
An arm 25 protruding laterally is provided on the side portion of the strain detection rod 22. Here, since the strain detecting rod 22 is constantly biased upward by the biasing spring 23, if no external force is applied to the strain sensing rod 22, the position where the strain sensing rod 22 is moved upward to the maximum, that is, the arm 25. Is held at a position where its upper end surface abuts the wall surface 2a of the base 2. However, when a downward force stronger than the urging force of the urging spring 23 acts on the strain detection rod 22, the strain detection rod 22 is pushed down according to the magnitude of this force.

A limit switch 28 having a spherical contact portion 26 and a rod 27 supporting the contact portion 26 is disposed below the arm 25. When a downward force acts on the contact portion 26, the limit switch 28 pushes down the rod 27 by this force to close an internal contact (not shown), and outputs an ON signal to the controller 19. . When no downward force is applied to the contact portion 26, the rod 27 is pushed back by the return spring (not shown) to open the internal contact, and the limit switch 28 outputs an off signal to the controller 19. It is supposed to be done. Specifically, an OFF signal is output when the center of the contact portion 26 is above the P ₂ position (for example, the P ₁ position), and an ON signal is output when the center of the contact portion 26 is below the P ₂ position. Is output.

In the strain detecting mechanism 13, if no external force is applied to the strain detecting rod 22, the strain detecting rod 22 and thus the arm 25 are arranged at a position where they are moved upward as much as possible. The end surface (inclined surface) does not apply a special downward force to the contact portion 26, and the limit switch 28 outputs an off signal. On the other hand, when a downward force stronger than the urging force of the urging spring 23 acts on the strain detection rod 22 and the strain detection rod 22 is pushed down, the arm 25 applies a downward force to the contact portion 26 accordingly. The limit switch 28 outputs an ON signal when the rod 27 is pushed down until the center of the contact portion 26 is below the P ₂ position. Here, the P ₂ position is set to the center position of the contact portion 26 when the upper end surface of the strain detection rod 22 is exactly at the same position as the upper end surface 2b of the base portion 2. That is, when the upper end surface of the strain detection rod 22 becomes lower than or equal to the upper end surface 2b of the base portion 2, the limit switch 28 outputs an ON signal.

In the trimming die TM, the shape correction device K automatically detects whether or not the case member 3 has a shape error in the trimming process, and the shape error is included. For example, the case member 3 is subjected to shape correction, and a specific procedure of such trimming and shape correction will be described below. First, the controller 19 causes the case member 3 to detect the case member 3 based on the signal output from the case member position detection mechanism 14.
It is determined whether or not it is arranged at the correct position of b. Here, if the case member 3 is not arranged at the correct position, the operation of the trimming die TM or the shape correction device K is temporarily stopped and an alarm is issued.

On the other hand, if the case member 3 is placed at the correct position, the controller 19 determines whether or not the case member 3 is accompanied by a shape error based on the output signal of the strain detection mechanism 13. judge. Specifically, if the ON signal is output from the limit switch 28, it is determined that the shape error is not involved (normal), and if the OFF signal is output, the shape error is involved (abnormal). Judge as something. That is, if the case member 3 is not accompanied by a shape error, the tip 3b 'of the case member 3'is set at the base 2 as shown by the phantom line in FIG.
It is located at the same position as the upper end surface 2b (excluding the recess 12). In this case, the strain detecting rod 22 is pushed downward by the case member 3, and the center of the contact portion 26 is at the P ₂ position.
Therefore, the limit switch 28 outputs an ON signal. Thus, when the ON signal is output from the limit switch 28, it is determined that the case member 3 has no shape error.

On the other hand, if the case member 3 is accompanied by a shape error, the tip 3b of the case member 3 has the base 2 (excluding the recess 12) as shown by the solid line in FIG. Is located above the upper end surface 2b of the. In this case, although the position of the strain detection rod 22 varies depending on the size of the shape error of the case member 3, at least the upper end surface of the strain detection rod 22 does not fall below the upper end surface 2b of the base portion 2. Therefore, in this case, the center of the contact portion 26 is a position above the P _2, for example, the P ₁ position. Therefore, the limit switch 28 outputs an off signal. Thus,
When the limit switch 28 outputs the off signal, it is determined that the case member 3 is accompanied by a shape error.

Next, the movable die M descends to a predetermined position,
Gate 10 and vacuum passage trace 1 attached to the case member 3
1. Burrs and the like are trimmed (cut) by the cutting blade 7 of the trimming member 6. If it is determined in the above-described shape error determination that the case member 3 is not accompanied by the shape error, the movable die M is lifted and the trimming process of the case member 3 this time is completed.

However, if it is determined in the above-mentioned shape error determination that the case member 3 is accompanied by a shape error, the shape error of the case member 3 is corrected by the following procedure. That is, hydraulic pressure is supplied from the hydraulic mechanism 18 to the first oil chamber (not shown) in the hydraulic cylinder 15 via the hydraulic pipe 17, and the distortion correcting rod 16 is pushed downward by the hydraulic pressure. Then, the lower end portion of the strain correction rod 16 comes into contact with the upper surface of the case member 3 in the vicinity of the tip thereof, and a downward pressing force is applied to this portion. Thus, the distortion correction rod 16
The part near the tip of the case member 3 is gradually deformed downward with the descending. Then, when the ON signal is output from the limit switch 28, the hydraulic pressure supply to the first oil chamber of the hydraulic cylinder 15 is stopped. At this time, the upper end surface of the strain detection rod 22, that is, the lower end surface of the case member 3 is at the same position as the upper end surface 2b of the base portion 2. That is, the shape error of the case member 3 is corrected and the case member 3 has a correct shape.

By the way, when the case member 3 is pressed by the strain correcting rod 16 in this way, the case member 3 maintains the correct shape, but when the pressing force is removed, the case member 3 is slightly in the original state ( There is a risk of returning to a state with a shape error). Therefore, the case member 3 is excessively pressed downward by the distortion correction rod 16 until the upper end surface of the strain detection rod 22, that is, the lower end surface of the case member 3 is located slightly below the upper end surface 2b of the base 2. You may do it. By doing so, the shape correction accuracy of the case member 3 is improved, and the quality of the case member 3 is improved. As described above, the concave portion 12 having a predetermined depth is provided at the upper end of the base portion 2 of the fixed mold F below the distortion correction rod 16, so that the lower end surface of the case member 3 is the base portion. The case member 3 can be excessively pressed downward until the case member 3 is located below the upper end surface 2b. Here, the depth of the concave portion 12 is preferably set so that such excessive pressing can be performed.

In this way, after the shape correction of the case member 3 is completed, the hydraulic pressure is supplied from the hydraulic mechanism 18 to the second hydraulic pressure (not shown) in the hydraulic cylinder 15 via the hydraulic pipe 17 to correct the distortion. The rod 16 is pulled back upward. After that, the movable mold M is raised, and the trimming or shape correction of this time is completed.

Thus, in the trimming or shape correction according to this embodiment, in the trimming step,
Since the shape correction device K attached to the movable mold M corrects the shape of the case member 3 that is a cast product, it is not necessary to separately provide a shape correction device or a shape correction process. Therefore, the post-treatment of the case member 3 is simplified, and the manufacturing cost of the case member 3 is reduced. Also,
Since it is not necessary to separately provide a shape correction device, it is only necessary to attach the shape correction device K to the existing trimming die.
The post-processing device of the case member 3 is simplified, the manufacturing cost thereof is reduced, and the manufacturing cost of the case member 3 is also reduced in this respect.

The strain detecting mechanism 13 is connected to the case member 3 by
The shape error (distortion or deformation) of the case member 3 can be detected, and according to the shape error of the case member 3 detected by the distortion detecting mechanism 13,
The operation of the distortion correction rod 16 (the amount of downward projection) may be controlled.

[Brief description of drawings]

FIG. 1 is a front cross-sectional explanatory view of a trimming die including a shape correction device according to the present invention.

FIG. 2 is an enlarged view showing the vicinity of a distortion detection mechanism of the trimming die shown in FIG.

[Explanation of symbols]

 TM ... Trimming mold F ... Fixed type M ... Movable type 2 ... Stand part 3 ... Case member 6 ... Trimming member 8 ... Cushion plate 12 ... Recessed portion 13 ... Strain detection mechanism 14 ... Case member position detection mechanism 15 ... Hydraulic cylinder 16 … Distortion correction rod 19… Controller 22… Strain detection rod 28… Limit switch

Claims (6)

[Claims] 1. A fixed die for holding a cast product and a movable die for trimming, which is provided with a movable die for trimming the cast product. A shape correction device for a cast product, comprising a shape correction member for performing a shape correction on the cast product in a trimming step. 2. The shape correction device for a cast product according to claim 1, wherein the shape correction member is a rod-like member fixed to the movable die, and the casting product is trimmed simultaneously with the movable die. A shape correction device for a cast product, characterized in that a shape is corrected by pressing. 3. The shape correction device for a cast product according to claim 1, wherein the shape correction member is a rod-like member that can move back and forth with respect to the cast product, and after the movable trimming operation. The shape correction device for a cast product, wherein the cast product is pressed toward the cast product to correct the shape by advancing toward the cast product. 4. The shape correction apparatus for a cast product according to claim 3, wherein the shape error detection means is attached to the fixed mold and detects presence or absence of a shape error of the cast product, and the shape error detection means. When it is detected that the cast product has a shape error, the shape correction member is provided with a shape correction member control means for correcting the shape error of the cast product. apparatus. 5. The shape correction device for a cast product according to any one of claims 2 to 4, wherein a pressing member for pressing and fixing the cast product to the fixed mold during trimming is provided on the movable mold. A shape correction member for a cast product, wherein the shape correction member is provided so as to penetrate the pressing member. 6. The shape correction device for a cast product according to claim 2, wherein the movable mold is arranged on the upper side, and the fixed mold is arranged on the lower side. A shape correction device for a cast product, characterized in that a recess having a predetermined depth is provided at an upper end of the fixed mold below the shape correction member.