JP5597984B2 - Casting equipment that casts inner diameter forming parts with high accuracy - Google Patents

Description

The present invention relates to a casting apparatus that casts an inner diameter forming portion and the like with high accuracy.

When casting a cylindrical inner peripheral surface using a die device such as aluminum die casting, a mold with a cavity inside is combined with a telescopic mold that forms the inner peripheral surface, and the mold is inserted. The molten metal is poured into the cavities between the child molds and cast. In such a case, it is necessary to provide a draft angle in order to separate the insert mold from the cast product during casting.
If casting is performed without a draft and the cast product is forcibly separated from the mold, a defect called “galling” occurs in which a part of the inner peripheral surface of the cast product is missing. Further, if casting is performed without a draft, the required force for separation, which is a force required for separation, becomes large, which causes an increase in the size and durability of the entire mold apparatus.
Usually, since the inner peripheral surface is often a cylindrical surface having a constant diameter, a cast product with a draft is cast, and the inner peripheral surface has to be cut by a machine tool later. . For this reason, the cost increase by secondary processing was forced, and the problem that the machining allowance became large due to the existence of the draft occurred.

  In order to cope with such a problem, a technique of forming a cast hole using a cast pin that does not require a draft, as shown in Patent Document 1, is known. This is because a cylindrical core pin is arranged in the space of the product shape part to be a cast product in the mold, and the core pin is continuously rotated around its axis or continuously in the axial direction. In the state of reciprocal movement, the molten metal is filled, waits for solidification, and if the core pin 6 is extracted after solidification, a circular core hole is formed in that portion.

In Patent Document 2, a molten metal is poured into a cavity, and after the molten metal is solidified and a cast product is formed, the slide core is rotated away from the cast product (using a cam groove), A straight inner peripheral surface is formed.
In these technologies, the solidification shrinkage of the aluminum itself does not change even if the core pin or slide core rotates continuously, and the inner diameter of the aluminum becomes smaller than the diameter of the core pin. A defect called “Hug” occurs on the pin. As a result, galling occurs in the cast pin when the draft angle is 0 °.

In addition, a technique of pulling out a slide pin as shown in Patent Document 3 is also known, but there is a limitation on the mold material because the mold material must be deformed. In addition, this prior art has a problem that due to the installation position of the spring, the radial mold cannot be deformed and the inner diameter shape cannot be formed over the entire circumference. It was.
The technique for detecting the solidification temperature of the molten metal is known from Patent Document 4, but it has only detected the optimum temperature for mold opening.

JP 2004-268077 A JP 2002-307156 A JP-A-8-108246 JP 2001-259819 A

This invention provides the casting apparatus which casts an internal diameter and an external shape formation part with high precision in view of the said problem.

In order to solve the above-mentioned problems, the invention of claim 1 is a casting apparatus for casting a cast product having an inner peripheral surface or an outer peripheral surface having a circular cross-sectional shape, and the casting apparatus includes a cavity ( 10), a nested mold (9) that is combined with the main mold (17) to form the inner peripheral surface or the outer peripheral surface, and during the solidification of the molten metal, Kinyuko mold (9) is rotated eccentrically, and provided with an eccentric mechanism which forms a clearance between the solidified while some molten metal and before Kinyuko mold (9), the eccentric mechanism section, before The reciprocating die (9) is configured to revolve and rotate, and the eccentric mechanism is rotatably supported by the revolving rotating body folder (3) and rotated by the rotation driving unit (1). The revolving rotating body (5) to be driven and the revolving rotating body (5) are incorporated so as to slide linearly. An eccentric amount positioning piece (4), and a telescoping shaft (7) provided on the eccentric amount positioning piece (4) and having an axis parallel to the rotation axis of the rotation drive unit (1), And a telescoping shaft (7) rotationally coupled to the telescoping mold (9), and the eccentric amount positioning piece (4) slides linearly within the revolving rotating body (5) by fluid pressure. The casting apparatus is configured as described above .
The invention according to claim 2 is a casting apparatus for casting a cast product having an inner peripheral surface or an outer peripheral surface having a circular cross-sectional shape, and the casting apparatus includes a main mold having a cavity (10) therein. (17), an insert mold (9) which is combined with the main mold (17) to form the inner or outer peripheral surface, and the insert mold (9) during solidification of the molten metal. It comprises an eccentric mechanism part that is eccentrically rotated to form a clearance between the solidified molten metal and the insert mold (9), and the eccentric mechanism part is a rotary shaft of the rotary drive part (1). An angular cam shaft (33) spline-coupled to (1 ′), the angular cam shaft (33) being disposed at the end opposite to the rotary shaft (1 ′). ) And the angular cam shaft (33). An angular cam shaft folder (34) that freely supports, and an eccentric amount adjustment mechanism (30) that moves the angular cam shaft folder (34) up and down along the axis of the rotary shaft (1 ′). The casting apparatus is characterized in that the eccentric cam (33 ′ ″) moves up and down to adjust the amount of eccentricity of the telescopic mold (9).

  Thereby, the product can be easily detached from the insert mold by the clearance between the insert mold and the cast-out part.

A third aspect of the invention is characterized in that, in the first or second aspect of the invention, a draft of the inner peripheral surface or the outer peripheral surface is 0 °.
As a result, the product can be easily removed from the insert mold by the clearance between the insert mold and the cast-out part, and as a result, a draft gradient of 0 ° can be realized.

The invention according to claim 1 is characterized in that the eccentric mechanism portion is configured to revolve and rotate the telescopic mold (9).
This allows the product to be easily removed from the insert mold due to the clearance between the insert mold and the cast-out part, and the inner and outer peripheral surfaces are work-hardened, the inner peripheral surface, The strength of the outer peripheral surface can be improved.

The invention according to claim 1 is characterized in that the eccentric mechanism part is rotatably supported by the revolution rotator folder (3) and is rotated by the rotation drive part (1). An eccentric amount positioning piece (4) built so as to slide linearly in the revolution rotating body (5), and provided on the eccentric amount positioning piece (4), are arranged on the rotating shaft of the rotation drive unit (1). A telescoping shaft (7) having a parallel axis, and a telescoping shaft (7) rotationally coupled to the telescoping mold (9), the eccentric amount positioning piece (4) Further, the present invention is characterized in that it is configured to slide linearly within the revolution rotator (5) by fluid pressure. Thereby, the product can be easily detached from the insert mold by the clearance between the insert mold and the cast-out part.

The invention according to claim 2 is characterized in that the eccentric mechanism portion is an angular cam shaft (33) spline-coupled to the rotation shaft (1 ′) of the rotation drive portion (1), and the angular cam shaft (33) is An angular cam shaft (33) having an angular cam (33 ''') at the end opposite to the rotary shaft (1'), and an angular cam shaft (33) for rotatably supporting the angular cam shaft (33). A regular cam shaft folder (34) and an eccentric amount adjusting mechanism (30) for moving the angular cam shaft folder (34) up and down along the axis of the rotary shaft (1 '). It is characterized in that the eccentric amount of the telescopic mold (9) is adjusted by the vertical cam (33 ′ ″) moving up and down.

  Thereby, the control of the eccentric amount is easy and can be accurately controlled. The inner peripheral surface and the outer peripheral surface can be processed with a constant pressure, and can be processed with an appropriate force required for deformation. Further, the eccentricity adjusting mechanism (30) makes it easy to determine the maximum eccentricity by a predetermined dimension, so that the inner diameter and the outer diameter can be set to predetermined dimensions.

The invention of claim 4 is characterized in that, in the invention of any one of claims 1 to 3 , the eccentric mechanism is controlled so that the amount of eccentricity increases as the solidification progresses.
Thereby, the amount of eccentricity can be accurately controlled, and the inner peripheral surface and the outer peripheral surface can be processed with a constant pressure.

According to a fifth aspect of the present invention, in the fourth aspect of the invention, a temperature sensor is disposed in the vicinity of the cavity, the solidification state of the molten metal is determined from the temperature of the temperature sensor, and the amount of eccentricity is determined based on the solidified state of the molten metal. It is characterized by an increase. Thereby, it can control accurately so that the amount of eccentricity may increase with progress of coagulation.

Cross-sectional shape is a casting method for casting a casting having an inner peripheral surface or outer peripheral surface is circular, the main mold (17), insert mold forming the inner peripheral surface or outer peripheral surface ( 9), injecting the molten metal into the cavity (10) formed between the main mold (17) and the nested mold (9), and during the solidification of the molten metal The casting method may include a step of eccentrically rotating the insert mold (9) to form a clearance between the molten metal being solidified and the insert mold (9) . In this case, the product can be easily detached from the insert mold by the clearance between the insert mold and the cast-out part.

  In addition, the code | symbol attached | subjected above is an example which shows a corresponding relationship with the specific embodiment as described in embodiment mentioned later.

It is sectional drawing which shows one Embodiment of this invention. It is the schematic which shows the principal part of a nested mold. BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing explaining the action | operation of the eccentric mechanism part of one Embodiment of this invention, (a) is explanatory drawing explaining the action | operation of the eccentric mechanism part in the case of rotating an insert metal mold | die with 0 eccentricity. (B) is an explanatory view for explaining the operation of the eccentric mechanism when the telescopic mold is rotated with the maximum eccentricity. It is sectional drawing regarding line AA of FIG. 3A explaining the action | operation of the eccentric mechanism part of one Embodiment of this invention. (A) is explanatory drawing of the eccentric mechanism part in case of eccentric amount 0, (b) is explanatory drawing of the eccentric mechanism part in case of eccentric amount is the maximum. (A) is the schematic which shows the principal part of another one Embodiment of this invention. FIG. 6B is a cross-sectional view taken along line BB of the eccentricity adjusting mechanism 30. (A) is the schematic which shows the principal part of another one Embodiment of this invention. FIG. 6B is a cross-sectional view taken along line BB of the eccentricity adjusting mechanism 30. It is sectional drawing of the eccentricity adjustment mechanism 30 in line CC of FIG. It is explanatory drawing which shows another one embodiment of the control method of the eccentric mechanism part of this invention.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. About each embodiment, the same code | symbol is attached | subjected to the part of the same structure, and the description is abbreviate | omitted.
FIG. 1 is a cross-sectional view showing an embodiment of the present invention. FIG. 2 is a schematic view showing a main part of the telescopic mold.

One embodiment of the present invention is a casting apparatus for casting a cast product having an inner peripheral surface having a circular cross-sectional shape. The insert mold 9 is combined with the main mold 17 having the cavity 10 therein to cast a cast product having an inner peripheral surface having a circular cross-sectional shape. An example of the casting method includes aluminum die casting, but is not limited thereto.
With reference to FIG. 1, the structure of the eccentric mechanism part of one Embodiment of this invention is demonstrated. The eccentric mechanism part eccentrically rotates the insert mold during the solidification of the molten metal to form a clearance between the molten metal being solidified and the insert mold.

A rotating shaft 1 ′ of the hydraulic motor 1 (corresponding to the rotation driving unit) is coupled to the revolution rotator 5 in a keyway, and when the hydraulic motor 1 is driven, the revolution rotator 5 rotates. Yes. The revolution rotator 5 is supported by the bearing 11 on the revolution rotator folder 3 fixed to the mounting plate 2. Reference numeral 15 denotes a revolving bearing stop. The hydraulic motor 1 constitutes a rotation drive unit, and the rotation drive unit may be an electric motor or the like. The revolution rotator 5 rotates around the rotation axis of the hydraulic motor 1 (rotation drive unit).
An eccentric amount positioning piece 4 is built in the cylinder chamber 20 (rectangular space) inside the revolution rotating body 5 so as to slide linearly.

FIG. 3 is an explanatory view for explaining the operation of the eccentric mechanism part according to the embodiment of the present invention. FIG. 3 (a) shows the operation of the eccentric mechanism part when the eccentric mold is rotated with zero eccentricity. It is explanatory drawing to explain, (b) is explanatory drawing explaining the action | operation of the eccentric mechanism part in the case of rotating an insert metal mold | die with the maximum amount of eccentricity. FIG. 4 is a cross-sectional view taken along line AA in FIG. 3A for explaining the operation of the eccentric mechanism of the embodiment of the present invention. (A) is explanatory drawing of the eccentric mechanism part in case of eccentric amount 0, (b) is explanatory drawing of the eccentric mechanism part in case of eccentric amount is the maximum.
As shown in FIG. 1, the eccentric amount positioning piece 4 has a center position working chamber 21 (see FIG. 3A) on the right side when it is moved to the left side (hereinafter referred to as “center position”). . On the other hand, when the eccentric amount positioning piece 4 is moved to the right side in FIG. 1 (hereinafter referred to as “eccentric position”), the eccentric position working chamber 22 (see FIG. 3B) exists on the left side.

The revolution rotating body folder 3 is provided with a first hydraulic pressure inlet / outlet 6. Even when the revolution rotator 5 is rotating, the hydraulic pressure introduced from the first hydraulic pressure inlet / outlet 6 passes through the first communication groove 14 provided over the entire outer peripheral surface of the revolution rotator 5 to the first through hole. The center position working chamber 21 can be reached through 6 '. Similarly, the revolution rotating body folder 3 is provided with a second hydraulic inlet / outlet 12. Even when the revolution rotator 5 is rotating, the hydraulic pressure introduced from the second hydraulic pressure inlet / outlet 12 passes through the second communication groove 18 provided over the entire outer peripheral surface of the revolution rotator 5 to the second through hole. 12 'can be passed to the eccentric position working chamber 22.
Reference numeral 13 denotes an O-ring, which is installed at three locations on the outer peripheral surface of the revolution rotating body 5 and separates the hydraulic system introduced from the first hydraulic inlet / outlet 6 and the hydraulic system introduced from the second hydraulic inlet / outlet 12. This prevents oil leakage. Reference numeral 16 denotes an eccentric amount positioning piece stopper, which prevents hydraulic pressure leakage by an O-ring.

  Here, even if the revolution rotator 5 rotates, the point that the oil can be supplied by the oil groove is simply supplemented. The revolution rotator folder 3 is fixed to the mounting plate 2, and the hydraulic pressure introduced from the first hydraulic inlet / outlet 6 provided in the revolution rotator folder 3 is the first communication groove even if the revolution rotator rotates. Since 14 is provided over the entire outer peripheral surface of the revolution rotator 5, it always communicates with the first through-hole 6 ′. Similarly, the second hydraulic inlet / outlet 12 is always in communication with the second through-hole 12 '.

The eccentric amount positioning piece 4 is provided with a nested rotation shaft 7 coupled with a keyway. At the center position, the rotary shaft 1 ′ and the nested rotation shaft 7 are coaxial (the amount of eccentricity = 0). At the eccentric position, the rotary shaft 1 ′ and the telescopic rotation shaft 7 are eccentrically rotated by the maximum eccentric amount e.
As shown in FIG. 2, the rotating rotation of the telescopic mold 9 is performed by attaching a bearing 8 between the telescopic rotating shaft 7 and the telescopic mold 9, and the telescopic mold 9 is free by the bearing 8. It can be rotated (referred to as rotational coupling). The insert mold 9 is composed of a insert 9 ′ and a mold cover 9 ″ of the main mold 17.
If the eccentric positioning pieces 4 are prepared by a plurality of different numbers of the following distances L, the maximum amount of eccentricity can be controlled by changing the shape of the eccentric positioning pieces 4. In FIG. 3A, the maximum amount of eccentricity e can be controlled by changing the distance L between the axis of the nested rotation shaft 7 and the right side surface of the eccentric amount positioning piece 4 at the center position. When L is reduced, the amount of eccentricity is greatly displaced.

With reference to FIGS. 3 and 4, the operation state of the center position in (a) and the eccentric position in (b) will be described.
(1) When the hydraulic motor is driven to rotate, the revolution rotator rotates.
(2) Oil flows from the second hydraulic pressure inlet / outlet 12.
(3) The eccentricity positioning piece 4 is moved by the inflow of oil.
(4) As shown in FIGS. 3B and 4B, the amount of eccentricity increases due to the movement of the eccentric amount positioning piece 4. FIG.

Next, another embodiment of the present invention that is different from the above-described embodiment regarding the eccentric mechanism will be described.
FIG. 5 (a) is a schematic view showing the main part of another embodiment of the present invention. FIG. 6B is a cross-sectional view taken along line BB of the eccentricity adjusting mechanism 30. FIG. 6 (a) is a schematic view showing the main part of another embodiment of the present invention. FIG. 6B is a cross-sectional view taken along line BB of the eccentricity adjusting mechanism 30. FIG. 7 is a cross-sectional view of the eccentricity adjustment mechanism 30 taken along line CC in FIG.

  As shown in FIG. 5, the angular cam shaft 33 includes an upper shaft 33 ′ and a lower shaft 33 ″ (both shafts are fixedly coupled by a flange or the like), and the upper shaft 33 ′ is the hydraulic motor 1. It is spline-coupled to the rotary shaft 1 ′ (corresponding to the rotary drive unit). An angular cam 33 ″ ″ is provided at the lower end of the lower shaft 33 ″ (the end opposite to the rotating shaft 1 ′).

  The angular cam has a rectangular cross-section and is bent in a dogleg shape in the axial direction as indicated by 33 ″ ″ in FIG. The angular cam 33 '' 'is inserted into the angular cam groove. As shown in FIG. 5, the angular cam groove is a slightly larger hole than the angular cam, the hole cross section is rectangular, and is bent in a dogleg shape in the axial direction. The upper portion of the lower shaft 33 ″ is a shaft portion having a circular cross section, and the lower portion of the lower shaft 33 ″ is an angular cam 33 ″ ″ having a rectangular cross section.

  The angular cam shaft 33 is supported by an angular cam shaft folder 34. In the angular cam shaft folder 34, as shown in FIG. 5, the upper shaft 33 'and the lower shaft 33 "are supported by a thrust bearing and a radial bearing. The angular camshaft folder 34 is divided in half by an upper folder 34 ′ and a lower folder 34 ″, and the upper folder 34 ′ and the lower folder 34 ″ are combined with a bolt. This is to insert and assemble the upper shaft 33 ′ and the lower shaft 33 ″ into the angular cam shaft folder 34.

The angular camshaft folder 34 is provided with protrusions 31, 31 on the left and right in FIG. 5 and is engaged with the cam groove 32 of the eccentricity adjustment mechanism 30. As shown in FIG. 7, the eccentricity adjusting mechanism 30 has a U-shaped cross section (line C = C in FIG. 5), and moves in a direction perpendicular to the axis of the rotary shaft 1 ′. Due to the horizontal movement of the eccentricity adjusting mechanism 30, the angular cam 33 ′ ″ having a rectangular cross section moves up and down while rotating with respect to the axis of the rotating shaft 1 ′. The eccentricity adjustment mechanism 30 does not move up and down, but reciprocates only in the F direction.
FIG. 6 shows a state where the eccentricity adjusting mechanism 30 has moved in a direction F perpendicular to the axis of the rotary shaft 1 ′. The protrusions 31, 31 have moved upward by D from the state of FIG.

When the angular cam 33 ′ ″ moves upward, the stepped portion is formed in a U shape in FIGS. 5 and 6, so that the eccentric amount of the insert 9 ′ is changed (see E in FIG. 6). . The angular cam 33 ′ ″ rotates the same as the rotating shaft 1 ′. An angular cam follower 38 is provided in the insert 9 '. The insert 9 'can rotate and rotate. The insert 9 'is rotatably mounted with respect to the angular cam follower 38 so that the insert 9' can freely rotate.
When the angular cam 33 ′ ″ having a rectangular cross section rotates, the angular cam follower 38 also rotates. When the angular cam 33 ′ ″ is at the lowermost position, the eccentricity is zero. When the angular cam 33 ′ ″ moves upward (the mold cover 9 ″, the angular cam follower 38 is regulated so as not to move upward), the angular cam follower 38 is eccentric, The regular cam follower 38 revolves. As a result, the same operation as in the above-described embodiment can be realized. In this case, the amount of eccentricity can realize a linear relationship with the amount of linear movement of the eccentricity adjusting mechanism 30.
A rod member having a stop portion 39 is provided at the tip of the angular cam 33 ′ ″. The stop part 39 is used when taking out the nest.

Next, the point that the eccentric mechanism unit is controlled so that the amount of eccentricity increases as the solidification progresses will be described.
Basically, the amount of solidification shrinkage is calculated from the temperature of the molten metal (aluminum, etc.), and the amount of increase in the eccentricity of the nest is controlled in conjunction with the amount of solidification shrinkage.
As an example, the calculation of the target value in the control of the eccentricity may be performed as follows.
A product part solidification shrinkage amount is calculated from the temperature of the product part, and a necessary amount of eccentric movement is calculated based on this. Next, if the flow control valve opening / closing amount of the eccentric control hydraulic valve and the total amount of hot water flowing through the eccentric control hydraulic cylinder are calculated, the eccentric movement amount (target eccentric amount) of the insert 9 'can be calculated. Thereby, the relationship between the flow control valve opening / closing amount of the eccentricity control hydraulic valve and the eccentric movement amount (target eccentricity amount) of the insert 9 ′ can be calculated.

In the measurement of the molten metal temperature and product part temperature, a temperature sensor is arranged in the vicinity of the cavity.
For example, the measurement positions of the mold temperature and the product temperature are measured at four points (two-point mold temperature, gate temperature, cavity temperature on the opposite side of the gate, etc.). The mold temperature may be measured using a sheathed thermocouple and a glass-coated thermocouple wire as a data logger.
In this way, the solidification state of the molten metal temperature and product part temperature is determined from the temperature of the temperature sensor, and control is performed to increase the amount of eccentricity based on the solidification state.

The actual amount of eccentricity is measured using a laser displacement meter or the like. In another embodiment of FIGS. 5 and 6, measurement may be performed by the amount of horizontal movement of the eccentricity adjustment mechanism 30. In one embodiment of FIG. 1, the mold cover 9 ″ may be guided by an Oldham coupling so as not to rotate, and the amount of eccentricity may be measured using a laser displacement meter or the like.
The eccentric control of one embodiment of the present invention and another embodiment can be performed by feedback control and feedforward control. First, the mold temperature and product temperature are measured, the target eccentricity is calculated, and the flow control valve opening of the eccentricity control hydraulic valve is adjusted. A known feedback control can be applied so that the deviation between the target eccentricity and the measured eccentricity is calculated and the deviation becomes zero. In the embodiment of FIG. 1, when the eccentricity measurement is not performed, the feedforward control can be performed. In the feedback and feedforward control, when the set maximum amount of eccentricity is reached, the increase in the amount of eccentricity ends.

  According to the present invention, there is an advantage that friction does not occur between the mold and the product at the time of mold release, even when the draft is not 0 °. In addition, shapes that can not be processed by die casting such as undercut shapes (such as reverse taper) can also be processed. For example, the present invention can also be applied to processing of female screw holes that cannot be processed by casting due to undercut. Furthermore, since processing is applied from the inside of the inner diameter surface, the inner surface of the aluminum is work-hardened and the strength of the inner surface can be improved. As an example of an application example of the present invention, a bearing mounting portion that requires high-precision dimensions and a site where components are engaged with each other can be considered as an example, but the present invention is not limited thereto.

Cross-sectional shape is a casting method for casting a casting having an inner peripheral surface or outer peripheral surface is circular, the main mold 17, and insert die 9 forming the inner peripheral surface or the outer peripheral surface A step of combining, a step of injecting a molten metal into a cavity 10 formed between the main mold 17 and the nested mold 9, and an eccentricity of the nested mold 9 during solidification of the molten metal A casting method comprising a step of rotating and forming a clearance between the molten metal being solidified and the insert mold 9 is also possible.

Also in this casting method, the amount of eccentricity is controlled so as to increase as the solidification progresses, or a temperature sensor is disposed in the vicinity of the cavity, and the solidification state of the molten metal is determined from the temperature of the temperature sensor. The amount of eccentricity may be increased based on the solidified state.
After combining the main mold 17 and the insert mold 9 that forms the inner peripheral surface or the outer peripheral surface, in the case of aluminum die casting, mold clamping is performed, but the torque of the rotary drive unit is set to a high torque. The telescopic mold 9 can slide with respect to the main mold 17.

Another method for controlling the amount of increase in the eccentricity of the nesting will be described. FIG. 8 is an explanatory diagram of this control method.
In another embodiment of FIG. 8, a timer receives a signal of completion of filling of molten metal (aluminum or the like) of the casting apparatus from the casting control apparatus, and the eccentric start hydraulic valve receives the timer signal after the reception, Start increasing eccentricity of nesting. The eccentric increase speed of the nesting is set in advance with the hydraulic valve for controlling the eccentric increase speed with reference to the evaluation result of the mold in which the thermocouple is arranged. Basically, it is good to calculate the amount of solidification shrinkage from the temperature of the molten metal (aluminum, etc.), and to control the amount of increase in the eccentricity in conjunction with the amount of solidification shrinkage, but by adopting various methods, It is possible to control the amount of eccentricity of the nest without arranging a thermocouple. This control is also applicable to the apparatus of the present invention.

DESCRIPTION OF SYMBOLS 1 Hydraulic motor 2 Mounting plate 3 Revolving rotator folder 4 Eccentricity positioning piece 5 Revolving rotator 6 1st hydraulic inlet / outlet 6 '1st through-hole 7 Nesting rotating shaft 8 Rotating bearing 9 Nesting die 10 Cavity 11 Revolving Bearing 12 Second hydraulic inlet / outlet 12 ′ Second through hole 13 O-ring 14 First communication groove 15 Revolving bearing stopper 16 Eccentricity positioning top stopper 17 Main mold 18 Second communication groove 30 Eccentricity adjustment mechanism 33 Angular cam Axis 33 '''Angular camshaft 34 Angular camshaft folder

Claims (5)

A casting apparatus for casting a cast product having an inner peripheral surface or an outer peripheral surface having a circular cross-sectional shape,
The casting apparatus comprises a main mold (17) having a cavity (10) therein;
Nesting mold (9) combined with the main mold (17) to form the inner peripheral surface or the outer peripheral surface;
An eccentric mechanism that eccentrically rotates the insert mold (9) during solidification of the molten metal to form a clearance between the solidified melt and the insert mold (9) ;
The eccentric mechanism portion is configured to revolve and rotate the telescopic mold (9),
Furthermore, the eccentric mechanism part is
A revolution rotator (5) rotatably supported by the revolution rotator folder (3) and driven to rotate by the rotation drive unit (1);
An eccentricity positioning piece (4) built in the revolving rotating body (5) so as to slide linearly;
An eccentric rotation shaft (7) provided on the eccentric amount positioning piece (4) and having an axis parallel to the rotation axis of the rotation drive unit (1), and is attached to the insertion mold (9) A rotationally coupled nested rotation shaft (7),
The casting apparatus according to claim 1, wherein the eccentric amount positioning piece (4) is configured to slide linearly within the revolution rotator (5) by fluid pressure . A casting apparatus for casting a cast product having an inner peripheral surface or an outer peripheral surface having a circular cross-sectional shape,
The casting apparatus comprises a main mold (17) having a cavity (10) therein;
Nesting mold (9) combined with the main mold (17) to form the inner peripheral surface or the outer peripheral surface;
An eccentric mechanism portion that eccentrically rotates the insert mold (9) during the solidification of the molten metal to form a clearance between the melt being solidified and the insert mold (9);
Comprising
The eccentric mechanism portion is
An angular cam shaft (33) splined to a rotary shaft (1 ') of the rotary drive unit (1), the angular cam shaft (33) being an end portion opposite to the rotary shaft (1') An angular cam shaft (33) having an angular cam (33 ''')
An angular cam shaft folder (34) for rotatably supporting the angular cam shaft (33);
An eccentric amount adjusting mechanism (30) for moving the angular cam shaft folder (34) up and down along the axis of the rotating shaft (1 ′);
The angular cam (33 ''') that moves up and down, casting apparatus eccentricity amount before Kinyuko mold (9) is characterized in that it is configured to be adjusted. Casting apparatus according to claim 1 or 2, characterized in that the draft of the inner or outer peripheral surface is 0 °. The casting apparatus according to any one of claims 1 to 3 , wherein the eccentric mechanism portion is controlled so that the amount of eccentricity increases as the solidification progresses. A temperature sensor disposed near the cavity, wherein the determining the solidified state of the molten metal from the temperature of the temperature sensor, based on the coagulation state of the melt, according to claim 4, characterized in that increased eccentricity Casting equipment.

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