Casting device and casting method

Abstract

To suppress an increase in a deformation amount of a die-cast product at the time of continuously casting the die-cast products.SOLUTION: A casting device 100 includes: a metal mold 10 composed of a movable die 30 and a stationary die 20 and provided with a cooling water flow path 32 therein; a mold tightening device 40; a cooling water pump 36; laser scanners 71, 72 for detecting an outer shape of a die-cast product 90; and a control part 80. After casting, when the metal mold 10 is separated, a CPU 81 of the control part 80 acquires the outer shape of the die-cast product from the laser scanners 71, 72, calculates a deformation amount for a design shape of the die-cast product on the basis of the acquired outer shape, and adjusts a mold tightening holding time or a cooling water flow amount on the basis of the calculated deformation amount.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a casting apparatus structure and a casting method using the casting apparatus. [Background technology]

[0002] Patent Document 1 discloses a casting device in which the dedicated part can be efficiently replaced by pulling out the dedicated part from the general-purpose part and attaching a new dedicated part. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-191065 Summary of the Invention [Problem to be solved by the invention]

[0004] However, when die-cast products are continuously cast using a casting apparatus such as that described in Patent Document 1, the die-cast products may become significantly deformed. However, the casting apparatus of the prior art does not detect the amount of deformation relative to the design shape of the die-cast product, and therefore it is not possible to feed back the amount of deformation to the casting conditions. For this reason, it is difficult to suppress the increase in deformation when continuously casting using the casting apparatus of the prior art.

[0005] Therefore, an object of the present disclosure is to suppress an increase in the amount of deformation of die-cast products when die-cast products are continuously cast. [Means for solving the problem]

[0006] The casting apparatus of the present disclosure is a casting apparatus for casting die-cast products, and includes: a mold composed of a movable mold and a fixed mold, the mold having a cooling water flow path provided therein; a mold clamping device for clamping and separating the mold; a cooling water pump for circulating cooling water through the cooling water flow path of the mold; a shape detector for detecting the outer shape of the die-cast product; and a control unit for adjusting the mold clamping hold time of the mold clamping device or the cooling water flow rate of the cooling water pump, wherein the control unit includes a processor for performing information processing, and when the mold is separated after casting, the processor acquires the outer shape of the die-cast product from the shape detector, calculates the amount of deformation of the die-cast product with respect to the design shape based on the acquired outer shape of the die-cast product, and adjusts the mold clamping hold time or the cooling water flow rate based on the calculated amount of deformation.

[0007] In this way, the mold clamping holding time or the cooling water flow rate is adjusted according to the amount of deformation of the die-cast product relative to the design shape after casting, thereby suppressing an increase in the amount of deformation of the die-cast product when casting continuously.

[0008] In the casting apparatus of the present disclosure, the processor may increase the cooling water flow rate when the calculated deformation amount exceeds a predetermined threshold.

[0009] This makes it possible to suppress the temperature rise of the die-cast product when continuous casting is performed, and to suppress an increase in the amount of deformation of the die-cast product.

[0010] In the casting apparatus of the present disclosure, the processor may increase the mold clamping hold time when the calculated deformation amount exceeds another predetermined threshold value.

[0011] Since cooling water is circulated through the mold during the mold clamping holding time, extending the mold clamping holding time can suppress the temperature rise of the die-cast product when continuous casting is performed, and can suppress an increase in the amount of deformation of the die-cast product.

[0012] In the casting apparatus of the present disclosure, the shape detector may be a laser scanner or an ultrasonic shape detector.

[0013] This allows the amount of deformation of the die-cast product to be detected without contact.

[0014] The casting method for a die-cast product of the present disclosure includes the steps of: preparing a casting apparatus including a mold composed of a movable mold and a fixed mold, the mold having a cooling water flow path therein; a mold clamping device that clamps and separates the mold; a cooling water pump that circulates cooling water through the cooling water flow path of the mold; and a shape detector that detects the outer shape of the die-cast product; detecting the outer shape of the die-cast product using the shape detector when the mold is separated after casting; calculating the amount of deformation with respect to the design shape of the die-cast product based on the detected outer shape of the die-cast product; and increasing the cooling water flow rate of the cooling water pump when the calculated amount of deformation exceeds a predetermined threshold, or lengthening the mold clamping holding time when the calculated amount of deformation exceeds another predetermined threshold.

[0015] This makes it possible to suppress an increase in the amount of deformation of die-cast products when continuous casting is performed. [Effects of the Invention]

[0016] The present disclosure can suppress an increase in the amount of deformation of die-cast products when die-cast products are continuously cast. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a system diagram showing a configuration of a casting device according to an embodiment. [Figure 2] 4 is a flowchart showing the operation of the casting device shown in FIG. 1 when casting a die-cast product. [Figure 3] FIG. 10 is an explanatory diagram showing the casting apparatus with the mold separated after casting. [Figure 4]FIG. 10 is a graph showing the change in deformation of a die-cast product and the change in cooling water flow rate with respect to the number of continuous castings. [Figure 5] 10 is a flowchart showing another operation of the casting device shown in FIG. 1 when casting a die-cast product. [Figure 6] FIG. 1 is a graph showing the change in deformation of a die-cast product and the change in mold clamping holding time with respect to the number of continuous castings. DETAILED DESCRIPTION OF THE INVENTION

[0018] A casting apparatus 100 according to an embodiment will now be described with reference to the drawings. As shown in Fig. 1, the casting apparatus 100 includes a mold 10, a mold clamping device 40, an extrusion device 50, an injection device 61, an exhaust pipe 62, a cooling water pump 36, laser scanners 71 and 72, and a control unit 80. In each drawing, the symbols FR, LH, and UP indicate the front, left, and top of the casting apparatus 100, respectively. The opposite directions of FR, LH, and UP are the rear, right, and bottom, respectively.

[0019] The mold clamping device 40 includes a fixed platen 41, a movable platen 42, tie bars 43, and a drive unit 45. The fixed platen 41 is fixed to the tip of the tie bar 43, which is a rod member. The movable platen 42 is disposed to face the fixed platen 41, and is moved forward along the tie bar 43 by the drive unit 45.

[0020] A mold 10 is attached to the mold clamping device 40. The mold 10 includes a fixed mold 20 and a movable mold 30. The fixed mold 20 is attached to the fixed platen 41, and the movable mold 30 is attached to the movable platen 42. The mold clamping device 40 opens and closes the mold 10 by moving the movable mold 30 in the forward and backward directions together with the movable platen 42. The movable mold 30 is then moved forward and pressed against the fixed mold 20, thereby clamping the mold 10. FIG. 1 shows the mold 10 in a clamped state by the mold clamping device 40. When the mold 10 is clamped, a cavity 12 is formed between the fixed mold 20 and the movable mold 30. The cavity 12 is a portion of the internal space of the mold 10 that has a shape corresponding to the shape of a die-cast product 90 (see FIG. 3). Here, the die-cast product 90 may be, for example, a vehicle body structural member.

[0021] As shown by the hollow arrow in Figure 1, the injection device 61 pressure-feeds molten metal, which is the material for the die-cast product 90, into the cavity 12 of the mold 10. Air in the cavity 12 is exhausted from an exhaust pipe 62 by a vacuum device (not shown) (see the arrow in Figure 1). The push-out device 50 includes an ejector pin 51, an ejector plate 52, and an ejector drive unit 55. When the mold 10 is separated, the push-out device 50 ejects the ejector pin 51, thereby releasing the die-cast product 90 from the movable mold 30.

[0022] The fixed mold 20 is composed of a main mold 21 and a nesting piece 25. The movable mold 30 is composed of a main mold 31 and a nesting piece 35. Here, the nesting pieces 25, 35 are parts of the fixed mold 20 and the movable mold 30 that are replaced depending on the die-cast product 90 to be molded. The main molds 21, 31 are parts that are fixed to the fixed platen 41 and the movable platen 42 of the mold clamping device 40, and are parts that are used in common for the die-cast product 90 to be molded.

[0023] A cooling water flow path 32 is provided inside the insert 35 of the movable mold 30. A cooling water pump 36 and a cooling water cooler 37 are connected to the cooling water flow path 32 by a cooling water pipe 38. Cooling water pressurized by the cooling water pump 36 flows into the cooling water flow path 32 of the insert 35. The cooling water whose temperature has increased in the cooling water flow path 32 is cooled by the cooling water cooler 37 and circulated to the cooling water pump 36. In this way, the cooling water pump 36 causes the cooling water to flow through the cooling water flow path 32 of the insert 35.

[0024] Laser scanners 71 and 72 are disposed slightly behind the fixed platen 41. The laser scanners 71 and 72 are shape detectors that irradiate a die-cast product 90 (see FIG. 3) with laser light and detect the outer shape of the die-cast product 90 by the reflected wave. The laser scanner 71 detects the outer shape of the upper part of the die-cast product 90, and the laser scanner 72 detects the outer shape of the lower part of the die-cast product 90.

[0025] The control unit 80 is a computer equipped with a CPU 81, which is an internal processor for information processing, and a memory 82 that stores control programs and control data. The drive unit 45 of the mold clamping device 40, the extrusion drive unit 55 of the extrusion device 50, the injection device 61, and the cooling water pump 36 are connected to the control unit 80 and operate according to commands from the control unit 80. The laser scanners 71 and 72 are also connected to the control unit 80, and detected external shape data of the die-cast product 90 is input to the control unit 80. The control unit 80 adjusts the mold clamping hold time T by the mold clamping device 40 or the cooling water flow rate Q of the cooling water pump 36, as will be described with reference to Figures 2 to 6.

[0026] 2 to 4, the operation of the casting device 100 when casting the die-cast product 90 will be described. A mold 10 is set in the casting device 100 as shown in FIG.

[0027] As shown in step 101 of FIG. 2, the CPU 81 of the control unit 80 operates the drive unit 45 of the mold clamping device 40 to move the movable platen 42 and the movable mold 30 forward, pressing them against the fixed mold 20 to clamp the mold 10. Then, in step 102 of FIG. 2, the CPU 81 of the control unit 80 operates the injection device 61 to inject molten metal into the cavity 12 of the mold 10. Then, in step 103 of FIG. 2, the CPU 81 operates the cooling water pump 36 to flow cooling water through the cooling water flow path 32. Then, the CPU 81 maintains the duty of the cooling water pump 36 at a predetermined value to maintain the cooling water flow rate Q at a predetermined flow rate, thereby maintaining the mold clamped state. As shown in step 104 of FIG. 2, the CPU 81 waits until a predetermined mold clamping hold time T has elapsed. Then, after the predetermined mold clamping hold time T has elapsed, the CPU 81 determines YES in step 104 of FIG. 2 and proceeds to step 105 of FIG. 2.

[0028] 2, the CPU 81 operates the drive unit 45 of the mold clamping device 40 to move the movable mold 30 backward together with the movable platen 42, as shown in FIG. 3, and separates the mold 10 into the fixed mold 20 and the movable mold 30. When the mold 10 is separated after casting, a die-cast product 90 is formed in the region of the cavity 12 shown in FIG. 1 (see FIG. 3). Furthermore, when the mold 10 is separated into the fixed mold 20 and the movable mold 30, the laser light from the laser scanners 71, 72 can reach the surface of the die-cast product 90. In step 105 of FIG. 2, the CPU 81 operates the ejection drive unit 55 of the ejection device 50 to move the ejection pin 51 forward, and releases the die-cast product 90 from the movable mold 30.

[0029] 2, the CPU 81 detects the outer shape of the die-cast product 90 using the laser scanners 71 and 72, and acquires data of the detected outer shape from the laser scanners 71 and 72. At this time, the CPU 81 acquires the outer shapes of the outer peripheries 91 and 92 of the die-cast product 90 where the amount of deformation Δ from the design shape is large. Then, in step 107 of FIG. 2, the CPU 81 compares the outer shape of the die-cast product 90 acquired from the laser scanners 71 and 72 with the design shape, and calculates the amount of deformation Δ from the design shape as the difference.

[0030] In step 108 of Fig. 2, the CPU 81 determines whether the deformation amount Δ exceeds a first threshold value Δs1. If the determination in step 108 of Fig. 2 is YES, the CPU 81 proceeds to step 109 of Fig. 2, where it increases the cooling water flow rate Q for the next casting to Q2, which is larger than the initial setting Q1. On the other hand, if the determination in step 108 of Fig. 2 is NO, the CPU 81 skips step 109 of Fig. 2 and proceeds to step 110 of Fig. 2. In step 110 of Fig. 2, the CPU 81 operates a robot (not shown) to remove the die-cast product 90 from the movable mold 30.

[0031] The CPU 81 determines whether casting has been performed a predetermined number of times in succession in step 111 of Fig. 2. If the determination in step 111 of Fig. 2 is YES, the CPU 81 stops continuous casting. On the other hand, if the determination in step 111 of Fig. 2 is NO, the CPU 81 returns to step 101 of Fig. 2 and starts the next casting.

[0032] Next, the change in the deformation amount Δ of the die-cast product 90 and the cooling water flow rate Q with respect to the number of continuous castings will be described with reference to Fig. 4. In Fig. 4, the solid line A shows the change in the deformation amount Δ, and the dashed line B shows the change in the cooling water flow rate Q.

[0033] As shown in Figure 4, when the first casting is performed, the cooling water flow rate Q is set to the initial setting of Q1. When the first casting is completed, the temperature of the die-cast product 90 at the end of casting is not very high, and the deformation amount Δ is also small.

[0034] As the number of continuous castings increases, the temperature of the die-cast product 90 at the end of casting gradually rises, and the deformation amount Δ gradually increases, as shown by the solid line A in Figure 4. Then, at the Nth casting, the deformation amount Δ exceeds the first threshold value Δs1. At this time, the outer peripheral portions 91, 92 of the die-cast product 90 are deformed, as shown by the dashed line in Figure 3. Then, the CPU 81 determines YES in step 108 of Figure 2 and increases the cooling water flow rate Q to Q2, which is larger than the initial setting Q1, in step 109 of Figure 2.

[0035] During the (N+1)th casting, the CPU 81 increases the duty of the cooling water pump 36 from the initial setting in step 103 of Fig. 2, and sets the cooling water flow rate Q of the cooling water passage 32 to Q2 (see dashed line B in Fig. 4). As a result, during the (N+1)th casting, the temperature of the die-cast product 90 during mold clamping and holding in step 104 of Fig. 2 becomes lower than during the Nth casting. Therefore, as shown by solid line A in Fig. 4, during the (N+1)th casting, the deformation amount Δ becomes smaller than the first threshold value Δs1.

[0036] After this, as the number of continuous casting operations increases, the deformation amount Δ again increases. When the deformation amount Δ again exceeds the first threshold value Δs1, the CPU 81 increases the cooling water flow rate Q again.

[0037] As described above, in the casting device 100, when the deformation amount Δ exceeds a predetermined threshold, the CPU 81 increases the cooling water flow rate Q, thereby suppressing the temperature rise of the die-cast product 90 when continuous casting is performed and suppressing the increase in the deformation amount Δ of the die-cast product 90.

[0038] Next, with reference to Figures 5 and 6, another operation of the casting apparatus 100 when casting the die-cast product 90 will be described. This other operation is an operation in which, when the deformation amount Δ exceeds a second threshold value Δs2, instead of increasing the cooling water flow rate Q, the mold clamping holding time T is lengthened. Operations that are the same as those previously described with reference to Figure 2 are assigned the same reference numerals, and their description will be omitted. Note that the second threshold value Δs2 is a threshold value different from the first threshold value Δs1.

[0039] As shown in FIG. 5, in another operation, the CPU 81 determines in step 201 of FIG. 5 whether the deformation amount Δ exceeds the second threshold value Δs2, and if the determination in step 201 of FIG. 5 is YES, the CPU 81 proceeds to step 202 of FIG. 5 and sets the mold clamping holding time T for the next casting to T2, which is longer than the initial setting T1.

[0040] Changes in the deformation amount Δ and mold clamping holding time T of the die-cast product 90 with respect to the number of continuous castings in other operations will be described with reference to Fig. 6. In Fig. 6, a solid line C indicates the change in the deformation amount Δ, and a dashed line D indicates the change in the mold clamping holding time T.

[0041] As shown in Fig. 6, when the deformation amount Δ exceeds the second threshold value Δs2 during the Mth casting, the CPU 81 sets the mold clamping hold time T to T2, which is longer than the initial setting T1, in step 202 of Fig. 5 (see dashed line D in Fig. 6). As a result, during the (M+1)th casting, the CPU 81 clamps and holds the mold using the mold clamping device 40 for T2, which is longer than the initial setting T1, so that the temperature of the die-cast product 90 is lower than during the Mth casting. Therefore, as shown by the solid line C in Fig. 6, during the (M+1)th casting, the deformation amount Δ is smaller than the second threshold value Δs2. This makes it possible to suppress an increase in the deformation amount Δ of the die-cast product 90 during successive castings.

[0042] In the above explanation, in other operations, the CPU 81 is described as lengthening the mold clamping holding time T instead of increasing the cooling water flow rate Q, but this is not limited to this, and the increase in the cooling water flow rate Q and the extension of the mold clamping holding time T may be performed in combination.

[0043] In the above description, the outer shape of the die-cast product 90 is detected using the laser scanners 71 and 72, but this is not limiting, and for example, an ultrasonic shape detector that uses ultrasonic waves to detect the outer shape of the die-cast product 90 may be used. This allows the outer shape of the die-cast product 90 to be detected in a non-contact manner.

[0044] In the above description, the cooling water flow path 32 is provided in the insert 35 of the movable mold 30, but this is not limiting. For example, a cooling water flow path may be provided in the insert 25 of the fixed mold 20, and cooling water may be passed through it by a cooling water pump 36. Furthermore, cooling water flow paths may be provided in both the insert 35 of the movable mold 30 and the insert 25 of the fixed mold 20, and cooling water may be passed through them.

[0045] The steps of the casting apparatus 100 described with reference to FIG. 2 also constitute a casting method executed by the casting apparatus 100. In this case, steps 105 and 106 in FIG. 2 are steps of detecting the outer shape of the die-cast product 90 using laser scanners 71 and 72 when the mold 10 is separated after casting. Step 107 in FIG. 2 is a step of calculating the deformation amount Δ of the die-cast product 90 relative to the design shape based on the outer shape of the die-cast product 90. Steps 108 and 109 in FIG. 2 are steps of increasing the cooling water flow rate Q of the cooling water pump 36 when the deformation amount Δ exceeds a predetermined threshold. Steps 201 and 202 in FIG. 5 are steps of lengthening the mold clamping hold time T when the deformation amount Δ exceeds a predetermined threshold. [Explanation of symbols]

[0046] 10 mold, 12 cavity, 20 fixed mold, 21, 31 main mold, 25, 35 insert, 30 movable mold, 32 cooling water flow path, 36 cooling water pump, 37 cooling water cooler, 38 cooling water piping, 40 mold clamping device, 41 fixed platen, 42 movable platen, 43 tie bar, 45 drive unit, 50 ejection device, 51 ejection pin, 52 ejection plate, 55 ejection drive unit, 61 injection device, 62 exhaust pipe, 71, 72 laser scanner, 80 control unit, 81 CPU, 82 memory, 90 die-cast product, 91, 92 outer periphery, 100 casting device.

Claims

1. A casting device for casting die-cast products, a mold including a movable mold and a fixed mold, and having a cooling water flow path provided therein; a mold clamping device that clamps and separates the mold; a cooling water pump that causes cooling water to flow through the cooling water flow path of the mold; a shape detector for detecting the outer shape of the die-cast product; a control unit that adjusts a clamping holding time of the mold by the mold clamping device or a cooling water flow rate of the cooling water pump, the control unit includes a processor that processes information, The processor: After casting, when the mold is separated, the outer shape of the die-cast product is acquired from the shape detector; calculating a deformation amount of the die-cast product relative to a design shape based on the acquired outer shape of the die-cast product; adjusting the mold clamping holding time or the cooling water flow rate based on the calculated deformation amount; A casting device characterized by:

2. The casting apparatus according to claim 1, the processor increases the cooling water flow rate when the calculated deformation amount exceeds a predetermined threshold; A casting device characterized by:

3. The casting apparatus according to claim 2, the processor extends the mold clamping hold time when the calculated deformation amount exceeds another predetermined threshold value; A casting device characterized by:

4. The casting apparatus according to any one of claims 1 to 3, the shape detector is a laser scanner or an ultrasonic shape detector; A casting device characterized by:

5. A method for casting a die-cast product, comprising the steps of: a step of preparing a casting machine including a mold consisting of a movable mold and a fixed mold, the mold having a cooling water flow path therein, a mold clamping device for clamping and separating the mold, a cooling water pump for circulating cooling water through the cooling water flow path of the mold, and a shape detector for detecting the outer shape of the die-cast product; a step of detecting the outer shape of the die-cast product by the shape detector when the mold is separated after casting; calculating a deformation amount of the die-cast product relative to a design shape based on the detected outer shape of the die-cast product; a step of increasing the cooling water flow rate of the cooling water pump when the calculated deformation amount exceeds a predetermined threshold, or a step of lengthening a clamping holding time of the mold when the calculated deformation amount exceeds another predetermined threshold, A casting method characterized by:

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