Patent Application
20220011206
This application is based on Japanese Patent Application No. 2020-118431 filed with Japan Patent Office on Jul. 9, 2020, the entire contents of which are hereby incorporated by reference.
The present disclosure relates to a strength measuring apparatus and a strength measuring method.
Japanese Unexamined Patent Publication No. H7-232235 discloses an apparatus which measures the strength of molds continuously conveyed. The apparatus includes a force sensor which measures the strength of molds and moving means which moves the force sensor. When a mold is carried into the apparatus, the force sensor is moved by the moving means to a position above a position where the strength of the mold should be measured and then lowered to a predetermined height. The force sensor comes into contact with the surface of the mold and measures the strength of the surface of the mold.
The size of the mold may be changed according to a product to be manufactured. Typically, the position where the strength of the mold should be measured is set in a part close to the outer edge of the mold so as not to affect the quality of the product. Thus, it is necessary to change the position where the strength of the mold should be measured according to the size of the mold. The present disclosure provides a technique capable of measuring the strength of a mold at an appropriate position regardless of the size of the mold.
A strength measuring apparatus according to one aspect of the present disclosure is provided on a conveyance line conveying a mold and measures a strength of the mold on the conveyance line. The apparatus includes: a strength measuring instrument measuring the strength of the mold on the basis of a reaction force received from the mold; a moving unit moving the strength measuring instrument; a distance sensor measuring a distance to an object on the conveyance line; and a control unit controlling the moving unit. The control unit determines a measurement position of the strength measuring instrument in a horizontal direction perpendicular to a conveyance direction of the conveyance line on the basis of the distance detected by the distance sensor and controls the moving unit to move the strength measuring instrument to a position above the measurement position.
In the strength measuring apparatus, the distance to the object on the conveyance line is measured by the distance sensor, and the measurement position of the strength measuring instrument in the horizontal direction perpendicular to the conveyance direction of the conveyance line is determined by the control unit on the basis of the measured distance. The strength measuring instrument is moved by the moving unit to the position above the measurement position. Since the measurement position is determined taking into consideration the distance to the object on the conveyance line in this manner, the strength measuring apparatus can measure the strength of the mold at an appropriate position regardless of the size of the mold.
In one embodiment, the distance sensor may be disposed so as to measure a distance in a height direction. The strength measuring apparatus may further include a sensor moving unit moving the distance sensor in the horizontal direction perpendicular to the conveyance line. The control unit may recognize an outer edge position of the object on the conveyance line on the basis of a change in the distance detected by the distance sensor and determine the measurement position on the basis of the outer edge position. In this case, the distance sensor measures the distance in the height direction while moving in the horizontal direction perpendicular to the conveyance line. Thus, the distance in the height direction can be obtained at each position in the direction perpendicular to the conveyance line. For example, a position where the distance along the height direction largely changes is regarded as the outer edge position of the object on the conveyance line, and the measurement position is determined on the basis of the outer edge position. In this manner, the strength measuring apparatus can measure the strength of the mold at an appropriate position on the basis of the change in the distance in the height direction.
In one embodiment, the distance sensor may be disposed so as to measure a distance in a height direction. The moving unit may move the distance sensor together with the strength measuring instrument in the horizontal direction perpendicular to the conveyance line. The control unit may recognize an outer edge position of the object on the conveyance line on the basis of a change in the distance detected by the distance sensor and determine the measurement position on the basis of the outer edge position. In this case, the strength measuring apparatus can measure the strength of the mold at an appropriate position on the basis of the change in the distance in the height direction without a sensor moving unit which moves the sensor alone.
In one embodiment, the distance sensor may be disposed so as to measure a distance in the horizontal direction perpendicular to the conveyance direction of the conveyance line. In this case, the control unit can recognize the outer edge position of the object on the conveyance line on the basis of the distance detected by the distance sensor and determine the measurement position on the basis of the outer edge position.
In one embodiment, the strength measuring apparatus may further include a positioning unit bringing the mold on the conveyance line to a standstill at a predetermined operation position. In this case, the strength measuring apparatus can measure the strength of the mold after the positioning unit brings the mold to a standstill at the predetermined operation position. Thus, the strength measuring apparatus can reduce a measurement error caused by misalignment of the mold.
In one embodiment, the control unit may determine whether a predetermined step relating to the mold is performable on the basis of the strength of the mold measured by the strength measuring instrument. In this case, for example, the strength measuring apparatus can avoid a case where the predetermined step is performed on the mold whose strength is not sufficient and a case where a waiting time for hardening is set for the mold whose strength is already sufficient.
In one embodiment, the predetermined step may be a pattern removing step. The control unit may output a pattern removal enabling signal when it is determined that the pattern removing step relating to the mold is performable. The strength measuring instrument may remeasure the strength of the mold after an elapse of a predetermined time when it is determined that the pattern removing step relating to the mold is not performable. In this case, the strength measuring apparatus can determine whether the pattern removing step is performable on the basis of the strength of the mold and remeasure the strength of the mold on which the pattern removing step is not performable after the waiting time for hardening.
In one embodiment, the strength measuring apparatus may include a storage unit associating the strength of the mold measured by the strength measuring instrument with the mold.
A strength measuring method according to another aspect of the present disclosure is a method for measuring a strength of a mold on a conveyance line using a strength measuring instrument, the method including: a step of measuring, using a distance sensor, a distance to an object on the conveyance line; a step of determining a measurement position of the strength measuring instrument in a horizontal direction perpendicular to a conveyance direction of the conveyance line on the basis of the distance detected by the distance sensor and moving the strength measuring instrument to a position above the measurement position; and a step of measuring, using the strength measuring instrument, the strength of the mold at the measurement position.
In the strength measuring method, the distance to the object on the conveyance line is measured by the distance sensor. The measurement position of the strength measuring instrument in the horizontal direction perpendicular to the conveyance direction of the conveyance line is determined on the basis of the distance detected by the distance sensor. The strength measuring instrument is moved to the position above the measurement position. The strength of the mold at the measurement position is measured by the strength measuring instrument. Since the measurement position is determined taking into consideration the distance to the object on the conveyance line in this manner, the strength measuring method can measure the strength of the mold at an appropriate position regardless of the size of the mold.
According to the technique of the present disclosure, it is possible to measure the strength of a mold at an appropriate position regardless of the size of the mold.
Hereinbelow, an embodiment of the present disclosure will be described with reference to the drawings. Note that, in the following description, identical reference signs designate identical or corresponding elements to omit redundant description. The dimensional ratio in the drawings does not necessarily coincide with an actual ratio. The “up”, “down”, “left” and “right” are based on an illustrated state and used for convenience sake.
Example of Casting System
In the molding place 2, mixed sand is charged into a molding flask F placed on a molding board B to manufacture the mold M. The mold M is, for example, a cope or a drag. The mixed sand contains a chemical solution (resin, a hardening agent) and casting sand, and is hardened with time. The mold M manufactured in the molding place 2 is fed to the conveyance line 3.
The conveyance line 3 is a facility which conveys the mold M from upstream to downstream. The conveyance line 3 receives the mold M from the molding place 2 and conveys the mold M placed on the molding board B to the pouring machine 5 located on the downstream side. The conveyance line 3 may include, for example, a driving roller, a roller conveyor, a rail, a carriage which travels on the rail, a pusher device which is disposed at the molding place 2 side, and a cushion device which is disposed at the pouring machine 5 side. In a case where the conveyance line 3 includes a driving roller, the molding board B is provided with a roller traveling surface. The conveyance line 3 linearly extends from the molding place 2 to the pouring machine 5. The conveyance line 3 may extend not linearly, but, for example, in a step-like manner. The conveyance line 3 may extend in a single stroke manner between the molding place 2 and the pouring machine 5. The conveyance line 3 sequentially conveys the molds M placed on a plurality of molding boards B, which are arranged at regular intervals on the driving roller, from the molding place 2 to the pouring machine 5. The conveyance line 3 is intermittently driven and conveys the molds M by a predetermined number of flasks at each drive. The predetermined number of flasks may be one flask or may be a plurality of flasks. The conveyance line 3 is communicably connected to the line controller 6. When receiving a flask feeding signal from the line controller 6, the conveyance line 3 conveys the plurality of molds M by the predetermined number of flasks. Upon completion of the conveyance of the predetermined number of flasks, the conveyance line 3 transmits a flask feeding completion signal to the line controller 6. The conveyance line 3 may transmit the flask feeding completion signal to the line controller 6 when positioning of the conveyed molds M is completed.
The strength measuring apparatus 4 is provided on the conveyance line 3 and performs measurement of the strength on the mold M on the conveyance line 3. The strength measuring apparatus 4 can be communicably connected to the line controller 6. The strength measuring apparatus 4, the conveyance line 3, and the line controller 6 may operate in cooperation with each other. Details of the strength measuring apparatus 4 will be described later.
A pattern removing machine W is an apparatus which removes a pattern P (refer to
The mold assembly apparatus 7 is an apparatus which mold-assembles a cope and a drag which are paired. The mold assembly apparatus 7 is provided between the pattern removing machine W and the pouring machine 5. The mold assembly apparatus 7 may set a core between the cope and the drag. The mold assembly apparatus 7 may be operated by an operator.
The pouring machine 5 is an apparatus which pours molten metal into the mold M. The pouring machine 5 is communicably connected to the line controller 6. When receiving the flask feeding completion signal from the line controller 6, the pouring machine 5 pours molten metal into the mold M located in a pouring area as a pouring target. The pouring machine 5 receives mold information from the line controller 6 and pours molten metal under a condition based on the mold information. The pouring machine 5 may perform the pouring in accordance with an operation of an operator who stays therein. The mold M with molten metal is conveyed to an area where a downstream process is performed through the conveyance line 3.
The line controller 6 is a controller which performs centralized control of the casting system 1. The line controller 6 is configured as, for example, a programmable logic controller (PLC). The line controller 6 may be configured as a computer system including a processor, such as a central processing unit (CPU), a memory, such as a random access memory (RAM) and a read only memory (ROM), an input/output device, such as a touch panel, a mouse, a keyboard, or a display, and a communication device, such as a network card. The line controller 6 implements the function of the line controller 6 by operating each hardware under control of the processor based on a computer program stored in the memory.
The line controller 6 controls the conveyance line 3 to intermittently convey the molds M with a predetermined standstill time. The standstill time is a time during which the molds M are at a standstill on the conveyance line 3 and previously determined in such a manner that the standstill time and a time during which the molds M move become alternate. For example, the conveyance line 3 conveys the molds M on the driving roller downstream by one flask and brings the molds M to a standstill. After the elapse of the predetermined standstill time, the conveyance line 3 conveys the molds M on the driving roller downstream by one flask and brings the molds M to a standstill. The conveyance line 3 repeatedly performs the conveyance and stopping of the molds M on the basis of the predetermined standstill time.
Details of Strength Measuring Apparatus
The strength measuring apparatus 4 may include a positioning unit 41. The positioning unit 41 brings the mold M on the conveyance line 3 to a standstill at a predetermined operation position. The operation position is a position where the strength measuring apparatus 4 measures the strength of the mold M and previously set on the conveyance line corresponding to the disposed position of the strength measuring apparatus 4. The positioning unit 41 is communicably connected to the line controller 6. The line controller 6 brings the conveyance line 3 to a standstill on the basis of the positioning unit 41. For example, the positioning unit 41 includes two proximity switches. The two proximity switches are disposed along the conveyance direction of the conveyance line 3 (X direction). The positioning unit 41 includes, for example, a first proximity switch which is disposed on the upstream side and a second proximity switch which is disposed on the downstream side.
The first proximity switch detects the molding board B, which is conveyed on the conveyance line 3, approaching the first proximity switch. The line controller 6 changes a conveyance speed of the conveyance line 3 to a low speed in response to the first proximity switch detecting the molding board B. The second proximity switch detects the molding board B, which is conveyed on the conveyance line 3, approaching the second proximity switch. The line controller 6 brings the conveyance line 3 to a standstill in response to the second proximity switch detecting the molding board B while the first proximity switch is detecting the molding board B. The positioning unit 41 including the two proximity switches can accurately bring the mold M to a standstill at the operation position by changing the conveyance speed at which the conveyance line 3 conveys the mold M to a low speed and then bringing the conveyance line 3 to a standstill.
The strength measuring instrument 10 includes a measuring unit 11 which comes into contact with the mold M. The strength measuring instrument 10 measures the strength of the mold M on the basis of a reaction force received by the measuring unit 11 from the mold M. The measuring unit 11 is, for example, a needle member. The strength measuring instrument 10 inserts the measuring unit 11 into the mold M to a predetermined depth and measures the reaction force received by the measuring unit 11. The measured reaction force serves as information indicating the strength of the mold M. For example, a reaction force received by the measuring unit 11 from the mold M which has been sufficiently hardened is larger than a reaction force received by the measuring unit 11 from the mold M which has not been sufficiently hardened. The reaction force received from the mold M may be converted into the compressive strength or the mold strength of the mold M.
The distance sensor 20 measures the distance to an object on the conveyance line 3. The distance sensor 20 is a sensor which measures the distance to an object present in a measurement direction. For example, the distance sensor 20 is a laser sensor, an ultrasonic sensor, or a contact sensor. The distance sensor 20 is disposed so as to measure the distance in the height direction (Z direction). That is, the distance sensor 20 is disposed facing the conveyance line 3 above the conveyance line 3. Accordingly, when an object is present under the distance sensor 20, the distance sensor 20 measures the distance to the object in the height direction. When an object is not present under the distance sensor 20, the distance sensor 20 measures the distance to the conveyance line 3 in the height direction.
The robot 30 moves the strength measuring instrument 10 and the distance sensor 20. The robot 30 supports the strength measuring instrument 10 and the distance sensor 20, and moves the strength measuring instrument 10 and the distance sensor 20 along the conveyance direction of the conveyance line 3 (X direction), a horizontal direction perpendicular to the conveyance direction of the conveyance line 3 (Y direction), and the height direction (Z direction). The robot 30 is a three-axis orthogonal robot which integrally moves the strength measuring instrument 10 and the distance sensor 20 in the X direction, the Y direction, and the Z direction. The robot 30 is, for example, supported on a frame 31 and disposed above the conveyance line 3 and the mold M.
The control device 40 is a controller which performs centralized control of the strength measuring apparatus 4. The control device 40 is configured as, for example, a PLC. The control device 40 may be configured as a computer system including a processor, such as a CPU, a memory, such as a RAM and a ROM, an input/output device, such as a touch panel, a mouse, a keyboard, or a display, and a communication device, such as a network card. The control device 40 implements the function of the control device 40 by operating each hardware under control of the processor based on a computer program stored in the memory. The control device 40 may be disposed outside the frame 31 or may be disposed inside the frame 31. The control device 40 is communicably connected to the strength measuring instrument 10, the distance sensor 20, and the robot 30. The control device 40 may be communicably connected to the line controller 6.
The control device 40 includes a control unit 50 and a storage unit 60. The control unit 50 controls the robot 30 to move the strength measuring instrument 10 and the distance sensor 20 in the horizontal direction perpendicular to the conveyance direction of the conveyance line 3 (Y direction). The control unit 50, for example, moves the strength measuring instrument 10 and the distance sensor 20 across the conveyance line 3 from an original position near one of two lateral ends, in the Y direction, of the conveyance line 3 toward the other lateral end. The distance sensor 20 moving in the Y direction continuously measures the distance in the height direction while moving. Consequently, the distance in the height direction can be obtained along the Y direction. The measured distance in the height direction is output from the distance sensor 20 to the control unit 50.
The control unit 50 determines a measurement position C1 of the strength measuring instrument 10 in the Y direction on the basis of the distance detected by the distance sensor 20. The measurement position C1 is a position on the upper face of the mold M where the strength is measured. For example, the control unit 50 recognizes an outer edge position of the object on the conveyance line 3 on the basis of a change in the distance detected by the distance sensor 20. For example, the control unit 50 recognizes, as the outer edge position of the object on the conveyance line 3, a position where the change in the distance in the height direction continuously measured along the Y direction becomes a threshold or more. Alternatively, the control unit 50 may recognize, as the outer edge position of the object, a position in the Y direction where the distance in the height direction becomes a threshold or less. In the example in the drawing, an outer edge position of the molding flask F is recognized as the outer edge position of the object. When the outer edge position of the molding flask F is recognized, the measurement position C1 of the mold M can be appropriately determined. For example, the measurement position C1 can be a position shifted by a predetermined distance from the outer edge position of the molding flask F toward the center of the mold M in the Y direction. The predetermined distance is set to be larger than the known thickness of the molding flask F. The measurement position C1 may be shifted in the X direction when the measurement position C1 interferes with the sprue or the product part of the mold M.
The control unit 50 controls the robot 30 to move the strength measuring instrument 10 and the distance sensor 20 to a position above the measurement position C1. When the control unit 50 detects the above-mentioned outer edge position of the object, the control unit 50 controls the robot 30 to temporarily stop the strength measuring instrument 10 and the distance sensor 20 and then move the strength measuring instrument 10 and the distance sensor 20 to the position above the measurement position C1. When the control unit 50 detects the above-mentioned outer edge position of the object, the control unit 50 may move the strength measuring instrument 10 and the distance sensor 20 to the position above the measurement position C1 without stopping the strength measuring instrument 10 and the distance sensor 20.
The control unit 50 acquires the distance in the height direction detected by the distance sensor 20 above the measurement position C1. Accordingly, the control unit 50 recognizes the distance to the vicinity of the surface of the mold M. The control unit 50 controls the robot 30 to lower the strength measuring instrument 10. The robot 30 inserts the measuring unit 11 provided on the lower part of the strength measuring instrument 10 into the mold M from the surface of the mold M. The strength measuring instrument 10 measures a reaction force received by the measuring unit 11. This enables the strength measuring instrument 10 to measure the strength of the mold M at the measurement position C1. Upon completion of the measurement of the strength measuring instrument 10, the control unit 50 controls the robot 30 to move the strength measuring instrument 10 and the distance sensor 20 to the original position.
In this manner, the control unit 50 not only determines the measurement position C in the Y direction on the basis of the detection result of the distance sensor 20, but also controls the position of the strength measuring instrument 10 in the Z direction on the basis of the detection result of the distance sensor 20. Thus, the control unit 50 can adjust the position of the strength measuring instrument 10 in the Y and Z directions on the basis of the detection result of the single distance sensor.
Moreover, the control unit 50 may determine whether a predetermined step relating to the mold M is performable on the basis of the strength of the mold M measured by the strength measuring instrument 10. The predetermined step is a step performed downstream of the strength measuring apparatus 4 on the conveyance line 3. For example, the control unit 50 compares the strength of the mold M measured by the strength measuring instrument 10 with a threshold to determine whether the predetermined step is performable on the mold M. The threshold is previously set on the basis of the strength of a mold on which the predetermined step has been normally performed. The predetermined step is, for example, a pattern removing step. The pattern removing step is an operation of removing the pattern P from the mold M, the operation being performed by the pattern removing machine W which is provided downstream of the strength measuring apparatus 4 on the conveyance line 3. The mold M having an insufficient strength may be broken by the pattern removing step. When the strength of the mold M is equal to or lower than the threshold, the control unit 50 determines that the pattern removing step is not performable due to the insufficient strength of the mold M.
When it is determined that the pattern removing step relating to the mold M is not performable, the control unit 50 may cause the strength measuring instrument 10 to remeasure the strength of the mold M after the elapse of a predetermined time. Since the self-hardening mold M is hardened with time, a waiting time for hardening is set for the mold M on which the pattern removing step is not performable. The control unit 50 outputs a signal to the line controller 6 to stop the conveyance line 3 until the remeasurement ends. Alternatively, the control unit 50 may output a signal to the line controller 6 to put the mold M on which it is determined that the pattern removing step is not performable standby at a standby place outside the conveyance line 3 and convey the mold M again after the elapse of a predetermined time.
When the remeasurement is performed, the control unit 50 may set the measurement position at a position different from the measurement position C1. This is because, if the strength is remeasured at the measurement position C1 in which the measuring unit 11 has been inserted, the strength measuring instrument 10 may not be able to accurately measure the strength of the mold M. The control unit 50 may set, as a new measurement position, a measurement position C2 symmetric to the measurement position C1 with respect to the center of the mold M. Alternatively, the control unit 50 may set, as a new measurement position, a measurement position shifted in the X direction from the measurement position C1.
The control unit 50 may repeat the setting of the waiting time and the remeasurement a predetermined number of times by controlling the strength measuring instrument 10 until it is determined that the pattern removing step is performable on the mold M. When it is determined that the pattern removing step is performable on the mold M, the control unit 50 outputs a pattern removal enabling signal to the line controller 6. The pattern removal enabling signal is a signal indicating that the pattern removing step is executable. When receiving the pattern removal enabling signal, the line controller 6 conveys the mold M to the pattern removing machine W located on the downstream side. When it is determined after the remeasurement that the pattern removing step is not performable, the control unit 50 may register the mold M as a defective mold.
The storage unit 60 associates the strength measured by the strength measuring instrument 10 with the mold M. The storage unit 60, for example, physically imparts information of the strength measured by the strength measuring instrument 10 to the mold M. The storage unit 60 may impart a radio frequency identifier (RFID) including the information of the strength measured by the strength measuring instrument 10 to the mold M. Alternatively, the storage unit 60 may impart or mark a bar code, a two-dimensional bar code, a number, a character string, or a symbol including the information to or on the mold M. A location to be imparted with the information is not limited to the mold M and may be the pattern P, the molding board B, or the molding flask F. Another piece of information may be associated with the mold M. Examples of the other piece of information include defective information, a serial number of the mold M, a molding time of day, and a molding condition. Examples of the molding condition include the amount of the chemical solution added in the mixing, the kind of the chemical solution, a sand-metal ratio, temperature, humidity, the temperature of sand before mixed, and a molding time.
Operation of Strength Measuring Apparatus
Next, as a moving step (step S20), the control unit 50 first determines the measurement position C1 of the strength measuring instrument 10 in the Y direction on the basis of the distance detected by the distance sensor 20. For example, the control unit 50 recognizes, as the outer edge position of an object on the conveyance line 3, for example, the position where the change in the distance in the height direction continuously measured along the Y direction becomes the threshold or more. Then, the control unit 50 sets the measurement position C1 at the position shifted by the predetermined distance from the outer edge position toward the center of the mold M in the Y direction. Then, the control unit 50 controls the robot 30 to move the strength measuring instrument 10 and the distance sensor 20 to the position above the measurement position C1.
At last, as a measuring step (step S30), the control unit 50 controls the robot 30 to lower the strength measuring instrument 10. The robot 30 inserts the measuring unit 11 provided on the lower part of the strength measuring instrument 10 into the mold M from the surface of the mold M. The strength measuring instrument 10 measures the reaction force received by the measuring unit 11 as the strength of the mold M. Upon completion of the measurement of the strength measuring instrument 10, the control unit 50 controls the robot 30 to move the strength measuring instrument 10 and the distance sensor 20 to the original position. In this manner, the flowchart illustrated in
According to the strength measuring apparatus 4 and the strength measuring method, the distance to the molding flask F on the conveyance line 3 is measured by the distance sensor 20, and the measurement position C1 of the strength measuring instrument 10 in the Y direction is determined by the control unit 50 on the basis of the measured distance. The strength measuring instrument 10 is moved by the robot 30 to the position above the measurement position C1. Since the measurement position C1 is determined taking into consideration the distance to the molding flask F on the conveyance line 3 in this manner, the strength measuring apparatus 4 and the strength measuring method can measure the strength of the mold M at an appropriate position regardless of the size of the mold M.
According to the strength measuring apparatus 4 and the strength measuring method, since the robot 30 integrally moves the strength measuring instrument 10 and the distance sensor 20, it is not necessary to include a plurality of moving units moving the strength measuring instrument 10 and the distance sensor 20. Moreover, the strength measuring apparatus 4 and the strength measuring method can not only determine the measurement position C1 in the Y direction on the basis of the detection result of the distance sensor 20, but also control the position of the strength measuring instrument 10 in the Z direction on the basis of the detection result of the distance sensor 20. Thus, according to the strength measuring apparatus 4 and the strength measuring method, it is possible to adjust the position of the strength measuring instrument 10 in the Y and Z directions on the basis of the detection result of the single distance sensor.
The strength measuring apparatus 4 and the strength measuring method can measure the strength of the mold M after the positioning unit 41 brings the mold M to a standstill at the predetermined operation position. Thus, the strength measuring apparatus 4 and the strength measuring method can prevent the measuring unit 11 from being mistakenly inserted into the product part or a casting plan part such as the sprue. The strength measuring apparatus 4 and the strength measuring method can determine whether the pattern removing step is performable on the basis of the strength of the mold M and also remeasure the strength of the mold M on which the pattern removing step is not performable after the elapse of the waiting time for hardening. The strength measuring apparatus 4 and the strength measuring method can avoid a case where the mold removing step is performed on the mold M whose strength is not sufficient and a case where the waiting time for hardening is set for the mold M whose strength is already sufficient. That is, it is possible to prevent a pattern removing failure caused by insufficient hardness of the mold M and prevent reduction in production efficiency. The strength measuring apparatus 4 and the strength measuring method can associate a mold M with the strength of the mold M.
Although various explanatory embodiments have been described above, the present invention is not limited to the above explanatory embodiments, and various omissions, replacements, and modifications may be made. In the following description, differences from the above embodiment will be mainly described, and redundant description will be omitted.
The mold M is not limited to a self-hardening mold, and may be, for example, a green sand mold, a gas-hardening mold, or a thermosetting mold.
The strength measuring apparatus 4 may not include the storage unit 60. The storage unit 60 may be provided separately from the control unit 50. The control unit 50 may not stop the conveyance of the mold M when it is determined that the pattern removing step is not performable.
The strength measuring instrument 10 may not include the measuring unit 11 which comes into contact with the mold M. The strength measuring instrument 10 may measure the strength of the mold M on the basis of a test piece acquired from the mold M.
The robot 30 which moves the strength measuring instrument 10 may not move the distance sensor 20. For example, the strength measuring apparatus may further include a sensor moving unit which moves a distance senor in the Y direction.
The strength measuring apparatus may further include a sensor moving unit which moves a distance sensor in the Z direction.
The robot may not move the distance sensor. In this case, the strength measuring apparatus includes a plurality of distance sensors.
Although, in the example of
The distance sensor may not measure the height of the mold M. The strength measuring instrument 10 may not bring the measuring unit 11 into contact with the mold M on the basis of the height of the mold M measured by the distance sensor.
The strength measuring apparatus is not limited to the apparatus which determines whether the pattern removing step is performable. For example, the strength measuring apparatus may determine whether a pouring step is performable.
The robot described above is not limited to the orthogonal robot. The robot may be, for example, a robot for movement in the direction of one axis or the directions of two axes, or may be a multi-articulated robot, a parallel-link robot, or a SCARA robot.
The molding place 2, the strength measuring apparatus 4, and the pattern removing machine W are disposed at respective positions corresponding to the molding board B, the pattern P, the molding flask F, and the mold M which are conveyed on the turntable. For example, the molding place 2, the strength measuring apparatus 4, and the pattern removing machine W may be disposed on the periphery of the turntable. In this case, a cylinder (not illustrated) which pushes out the molding board B, the pattern P, the molding flask F, and the mold M to the periphery of the turntable may be provided on the center of the turntable.
In the molding place 2, mixed sand is charged into the molding flask F and the pattern P which are placed on the molding board B to manufacture the mold M. The mold M manufactured in the molding place 2 is fed to the turntable. In the following, description will be made assuming that the position where the molding place 2 for manufacturing the mold M is disposed is the most upstream conveyance position of the turntable.
The strength measuring apparatus 4 is disposed downstream of the molding place 2. The strength measuring apparatus 4 is located in the counterclockwise circumferential direction when viewed from the molding place 2. The strength measuring apparatus 4 includes a horizontal-direction distance sensor 20 (e.g., refer to
The pattern removing machine W is disposed downstream of the strength measuring apparatus 4. The pattern removing machine W removes the pattern P and the molding flask F from the mold M carried thereinto. The mold M separated from the pattern P and the molding flask F is carried out of the turntable. The pattern P and the molding flask F are placed on the molding board B and carried out to the turntable again. The pattern P and the molding flask F carried out of the pattern removing machine W are carried into the molding place 2 again.
As described above, also in the case where the molds M are annularly conveyed as illustrated in
1 . . . casting system, 2 . . . molding place, 3 . . . conveyance line, 4 . . . strength measuring apparatus, 5 . . . pouring machine, 6 . . . line controller, M . . . mold, F . . . molding flask, B . . . molding board, P . . . pattern, 10 . . . strength measuring instrument, 11 . . . measuring unit, 20, 20A, 20B, 20C, 20D, 20E . . . distance sensor, 30, 30A, 30B . . . robot, 40 . . . control device, 41, 41A . . . positioning unit, 50 . . . control unit, 60 . . . storage unit.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2020-118431 | Jul 2020 | JP | national |
