JP2023182220A - production system - Google Patents

Abstract

To provide a production system which can reduce a processing cost regardless of variation of workpieces.SOLUTION: A data processing apparatus 7 constituting a production system 1 determines start positions X2 and X12 of an idle running operation S3a on the basis of shape information of a workpiece W measured by a shape measuring device 3 so as to equalize travel distances L2 and L12 of the idle running operation S3a and outputs the determined start positions X2 and X12 of the idle running operation S3a to a downstream processing facility 4 as command information. In machining processing for the workpiece W being an object, the downstream processing facility 4 changes the start positions X2 and X12 of the idle running operation S3a on the basis of the command information acquired from the data processing apparatus 7.SELECTED DRAWING: Figure 5

Description

The present invention relates to a production system.

Patent Document 1 describes a cyber-physical production system. This production system generates a virtual production state in a virtual world, autonomously modifies production command values to meet the production conditions of the production line based on the virtual production state, and produces production based on the modified production command values. Operate the line. Production conditions include tool cost, power consumption, downtime, and quality.

JP2020-177580A

Among the processing equipment that makes up a production line that performs multiple processes on a workpiece, in the processing equipment that performs machining processing using tools, the workpiece and tool gradually move from a distant position until they come into contact. The workpiece and tool are brought close to each other, and actual machining is performed after contact. In particular, in processing equipment that performs grinding and finishing cutting, the relative movement speed between the workpiece and tool during grinding and finishing cutting is extremely slow compared to other processing equipment.

In grinding or finishing cutting, the workpiece and tool are brought into contact while moving at a processing speed (for example, rough grinding speed). Therefore, the machining speed is changed before the workpiece and tool come into contact.

Furthermore, there are variations in the shape of the workpiece to be subjected to grinding or finishing cutting. Therefore, in the case of a workpiece having a large diameter, there is a risk that the workpiece and the tool will come into contact with each other because they are brought too close together during high-speed movement (for example, during air-grinding movement). In order to avoid this situation, a sufficient free running distance is ensured from the start position of movement at the machining speed to the position where the workpiece and tool come into contact. Generally, the idle running distance is set to a distance that matches the maximum shape of the variations in the workpiece, taking into account variations in the shape of the material of the workpiece. The relative movement speed between the workpiece and the tool during the free running distance is the machining speed, and is therefore the speed at which, for example, grinding or finishing cutting is performed. Therefore, in the case of a workpiece whose material shape is small in diameter, the idle running distance becomes long and the wasted time during which no machining is performed becomes long. As a result, the processing cost in consideration of time becomes high.

The present invention has been made in view of this problem, and aims to provide a production system that can reduce processing costs even when there are variations in workpieces.

One aspect of the present invention includes upstream processing equipment that performs processing on a workpiece to change the shape of the workpiece;
a shape measuring device that measures the shape of the workpiece after being processed by the upstream processing equipment;
downstream processing equipment that performs machining processing using a tool on the workpiece processed by the upstream processing equipment;
The shape information of the workpiece measured by the shape measuring device is acquired, and before the downstream processing equipment performs the machining process on the workpiece to be measured, based on the shape information of the workpiece. a data processing device that outputs the obtained command information to the downstream processing equipment;
Equipped with
The machining process by the downstream processing equipment includes:
A free running operation of bringing the tool into contact with the workpiece by moving the tool relatively closer to the workpiece from a starting position where the workpiece and the tool are separated from each other at a predetermined speed;
After the idle running operation, the tool is moved relative to the workpiece at the same speed as the predetermined speed in the idle running operation, and the workpiece is actually machined by the tool. The actual machining operation to be performed,
including;
The data processing device determines the start position of the free running motion based on the shape information of the workpiece so that the moving distance of the free running motion is constant, and Outputting the start position of as the command information to the downstream processing equipment,
In the production system, the downstream processing equipment changes the start position of the idle operation based on the command information acquired from the data processing device in the machining process for the target workpiece.

The above production system includes upstream processing equipment and downstream processing equipment. In the downstream machining equipment, when performing machining processing using a tool on a workpiece machined by the upstream machining equipment, an actual machining operation is performed after performing a free running operation. Here, the upstream processing equipment performs processing that changes the shape of the workpiece. Therefore, the actual machining operation in the downstream processing equipment is an operation according to the shape of the workpiece machined by the upstream processing equipment.

Here, the production system includes a shape measuring device and a data processing device. The shape measuring device measures the shape of the workpiece after being processed by the upstream processing equipment. The data processing device acquires shape information of the workpiece measured by the shape measuring device, and obtains information based on the shape information of the workpiece before the downstream processing equipment performs machining processing on the workpiece to be measured. The received command information is output to downstream processing equipment.

Then, the data processing device determines the starting position of the free running motion based on the shape information of the workpiece so that the moving distance of the free running motion is constant, and uses the determined starting position of the free running motion as command information. Output to downstream processing equipment. The downstream machining equipment changes the start position of the idle motion with respect to the target workpiece by acquiring command information from the data processing device. In other words, even if there are variations in the shape of the workpiece after machining by the upstream machining equipment, the moving distance of the idle running operation in the downstream machining equipment is always constant. Therefore, it is possible to suppress an increase in machining cost due to a longer idle running operation.

As described above, according to the above aspect, it is possible to provide a production system that can reduce processing costs even when there are variations in workpieces.

FIG. 1 is a diagram showing the configuration of a production system. It is a diagram showing a grinder as an example of downstream processing equipment that constitutes the production system. It is a flowchart which shows the machining process (grinding process) in a grinder. It is a figure which shows the change of the X-axis position of a grinding wheel in the machining process (grinding process) in a grinding machine. It is a figure which shows the change of the X-axis position of a grinding wheel in the machining process (grinding process) in a grinding machine. 3 is a flowchart showing processing of the data processing device. FIG. 7 is a diagram illustrating the processing of the downstream processing equipment according to the dimensions measured by the shape measuring device, regarding the processing of S13 in FIG. 6 . It is a figure for explaining the interval of tool modification of a grinder. It is a flow chart showing processing of downstream processing equipment. It is a diagram showing the configuration of a modified production system.

(Embodiment)
1. Configuration of Production System 1 The configuration of the production system 1 will be described with reference to FIG. 1. The production system 1 includes a plurality of production facilities 2 to 5, a management device 6, and a data processing device 7. The plurality of production facilities 2 to 5 are, for example, production facilities for producing workpieces W, and sequentially perform processing on the workpieces W.

The production facilities 2 to 5 are, for example, an upstream processing facility 2, a shape measuring device 3, a downstream processing facility 4, and an inspection device 5. However, the production system 1 only needs to include at least an upstream processing facility 2, a shape measuring device 3, and a downstream processing facility 4, and may optionally include other production facilities.

The upstream processing equipment 2 performs processing on the workpiece W to change the shape of the workpiece W. The upstream processing equipment 2 includes, for example, processing equipment that performs removal processing (cutting, grinding, etc.) such as a lathe, machining center, gear cutting device, and grinder, processing equipment that performs forging or casting, and heat treatment equipment that performs heat treatment. These include equipment that performs surface treatment, laser processing equipment, etc.

The shape measuring device 3 measures the shape of the workpiece W after processing by the upstream processing equipment 2. For example, when the workpiece W has an outer peripheral surface or an inner peripheral surface with a circular cross-sectional shape, the shape measuring device 3 determines the diameter dimension of the outer peripheral surface or the inner peripheral surface of the workpiece W as the shape of the workpiece W. Measure. The shape measuring device 3 may be either a contact type or a non-contact type. The shape of the workpiece W is not limited to the above case but can be any shape, and the shape measuring device 3 measures dimensions etc. according to the shape of the workpiece W.

The downstream machining equipment 4 performs machining processing using the tool T on the workpiece W machined by the upstream machining equipment 2 . In particular, the downstream processing equipment 4 performs machining processing on the workpiece W, taking into account the shape information of the workpiece W measured by the shape measuring device 3 and the like. The downstream processing equipment 4 is, for example, processing equipment (machine tool) that performs removal processing (cutting processing, grinding processing) or polishing processing, such as a lathe, machining center, gear cutting device, grinder (used to include polishing machine), etc. be.

The inspection device 5 inspects the shape of the workpiece W after processing by the downstream processing equipment 4. The inspection device 5 can, for example, measure the dimensions of the workpiece W in the same way as the shape measurement device 3, measure the surface properties (surface roughness, roundness, cylindricity, etc.) of the workpiece W, and The presence or absence of a process-affected layer in W is inspected. The inspection items of the inspection device 5 can be set arbitrarily.

The management device 6 stores, for example, a production plan. The management device 6 may have a function of generating a production plan. The production plan includes management data such as, for example, a production date (delivery date) for each workpiece W, process information for the workpiece W, and an execution schedule for each process. Management data is input into the management device 6 by an administrator.

The data processing device 7 determines command information for each of the production facilities 2 to 5 regarding the operation of each of the production facilities 2 to 5 based on the production plan in the management device 6, and Output command information. Furthermore, the data processing device 7 can also determine command information for each of the other production facilities 2 to 5 based on the information acquired from each of the production facilities 2 to 5. For example, the data processing device 7 can determine command information for the production facilities 2 to 5 on the downstream side using information on the production facilities 2 to 5 on the upstream side. In other words, the data processing device 7 can control each of the production facilities 2 to 5 to operate in cooperation with respect to matters that are related to each other.

For example, the data processing device 7 acquires the production plan from the management device 6, acquires the operating status information of the upstream processing equipment 2, and instructs the shape measuring device 3 regarding the measurement type, measurement start timing, etc. can do.

Further, the data processing device 7 acquires shape information of the workpiece W measured by the shape measuring device 3, determines command information such as processing conditions for the downstream processing equipment 4, and transmits the command information to the downstream processing equipment 4. can be output. For example, the data processing device 7 uses the shape information of the workpiece W based on the acquired shape information of the workpiece W before the downstream processing equipment 4 performs machining processing on the workpiece W to be measured. The command information obtained based on the command information is outputted to the downstream processing equipment 4, and the downstream processing equipment 4 is caused to perform an operation according to the command information.

Further, the data processing device 7 can also function as a device for realizing processing of virtual space in a cyber-physical production system (CPPS). In this case, the data processing device 7 executes the operations of the production facilities 2 to 5 in the real world in the virtual space in real time, and uses the processing results to control the operations of the production facilities 2 to 5 in the real world in real time. Can be done. For example, the data processing device 7 optimizes the processing conditions of the downstream processing equipment 4 based on the results obtained from the upstream processing equipment 2 and the shape measuring device 3, the processing conditions of the downstream processing equipment 4, etc. Processing conditions optimized for the processing equipment 4 can be output.

The data processing device 7 also acquires the production plan from the management device 6 and the operating status information of the downstream processing equipment 4, and provides command information such as the type of inspection and the start timing of the inspection to the inspection device 5. The determined command information can be output to the inspection device 5.

Furthermore, the data processing device 7 may be configured separately from the device bodies of the production facilities 2 to 5, such as a server or a cloud computer. In addition, some functions of the data processing device 7 can be configured as a server, a cloud computer, etc., and other functions can be configured as an embedded system in the production equipment 2 to 5. Further, the data processing device 7 may not be configured independently from the production facilities 2 to 5, but may be configured as an embedded system in each of the production facilities 2 to 5.

2. Configuration of Downstream Processing Equipment 4 An example of the configuration of the downstream processing equipment 4 will be described with reference to FIG. 2. In this embodiment, the downstream processing equipment 4 is exemplified by a cylindrical grinder. In FIG. 2, a grindstone traverse type cylindrical grinder is taken as an example of the downstream processing equipment 4, but a table traverse type cylindrical grinder or a grinder having another configuration may also be applied.

The grinding machine serving as the downstream processing equipment 4 includes a bed 21 , a workpiece support 22 , a traverse base 23 , and a grindstone head 24 . The workpiece support stand 22 is provided on the upper surface of the bed 21, and includes, for example, a headstock that supports one end of the shaft-shaped workpiece W, and a tailstock that supports the other end. Further, the headstock and tailstock that constitute the workpiece support stand 22 allow the workpiece W to rotate around the Cw axis.

The traverse base 23 is configured to be movable on the upper surface of the bed 21 in a direction parallel to the axial direction of the workpiece W (Z-axis direction). The grindstone head 24 is configured to be movable on the upper surface of the traverse base 23 in a direction toward and away from the workpiece W (X-axis direction). Further, the grindstone head 24 rotates a grindstone serving as the tool T around the Ct axis. A grinding machine serving as the production equipment 2 grinds the workpiece W by relatively moving the workpiece W and a grinding wheel serving as the tool T. In this embodiment, the workpiece W has a cylindrical outer peripheral surface, and a grinding machine serving as the downstream processing equipment 4 grinds the outer peripheral surface of the workpiece W using a grinding wheel serving as the tool T.

3. Machining Processing by Downstream Processing Equipment 4 The machining process by the grinding machine that is the downstream processing equipment 4 shown in FIG. 2, that is, the grinding process will be described with reference to FIGS. 3 to 5. In this embodiment, the grinder executes multiple types of grinding processes (air grinding process, rough grinding process, fine grinding process, fine grinding process, spark-out process, etc.). However, the downstream processing equipment 4 may be configured to perform one type of machining process.

4(a) corresponds to FIG. 5(a), and FIG. 4(b) corresponds to FIG. 5(b). 4(a) and 5(a) show the case where the outer diameter of the workpiece W after processing by the upstream processing equipment 2 is a small value Da, and FIG. 4(b) and FIG. This is a case where the outer diameter of the workpiece W is a large value Db.

As shown in FIG. 3, in the machining process (grinding process), a fast forward forward step S1 is performed to bring the grinding wheel, which is the tool T, closer to the workpiece W (t0→t1, t10→t11 in FIG. 4). . As shown in FIGS. 4(a) and 4(b), in the fast forward forward step S1, the X-axis position of the center Ct of the grinding wheel moves from X0 to X1 in rapid forward movement. In the fast forward forward step S1, when the X-axis position of the center Ct of the grinding wheel reaches X1, the air grinding step S2 is started (t1→t2, t11→t12 in FIG. 4).

In the air grinding step S2, the moving speed of the grinding wheel is made slower than in the fast forward forward step S1. As shown in FIGS. 4(a) and 5(a), in the case of the outer diameter Da of the workpiece W, in the air grinding process S2, the X-axis position of the center Ct of the grinding wheel changes from X1 to X2. Moves at grinding speed. In the air grinding step S2, when the X-axis position of the center Ct of the grinding wheel reaches X2, the rough grinding step S3 is started (t2→t4 in FIG. 4).

As shown in FIG. 5(a), when the X-axis position of the center Ct of the grinding wheel is located at X1, the grinding wheel is located at a position indicated by T(t1). When the X-axis position of the center Ct of the grinding wheel is located at X2, the grinding wheel is located at a position indicated by T(t2). In the case of the outer diameter Da of the workpiece W, in the air grinding process S2, the point P of the grinding wheel closest to the workpiece W moves from the point P(t1) to the point P(t2) in the X-axis direction. moves by a distance L0. Point P(t1) is located at a position separated from workpiece W by L1 in the X-axis direction. Point P(t2) is located at a position separated from workpiece W by L2 in the X-axis direction.

As shown in FIG. 4(b) and FIG. 5(b), in the case of the outer diameter Db of the workpiece W, in the air grinding process S2, the X-axis position of the center Ct of the grinding wheel changes from X1 to X12. Moves at grinding speed. In the air grinding step S2, when the X-axis position of the center Ct of the grinding wheel reaches X12, the rough grinding step S3 is started (t12→t14 in FIG. 4).

As shown in FIG. 5(b), when the X-axis position of the center Ct of the grinding wheel is located at X1, the grinding wheel is located at a position indicated by T(t11). When the X-axis position of the center Ct of the grinding wheel is located at X12, the grinding wheel is located at a position indicated by T (t12). In the case of the outer diameter Db of the workpiece W, in the air grinding step S2, the point P of the grinding wheel closest to the workpiece W moves from the point P (t11) to the point P (t12) in the X-axis direction. It moves by a distance L10. Point P (t11) is located at a position separated from workpiece W by L11 in the X-axis direction. Point P (t12) is located at a position separated from workpiece W by L12 in the X-axis direction.

The center point X12 shown in FIG. 5(b) is located closer to the center Cw of the workpiece W than the center point X2 shown in FIG. 5(a). The relationship between point P (t12) and point P (t2) is also similar. In detail, the separation distance L2 between the point P (t2) in FIG. 5(a) and the workpiece W having the outer diameter Da, and the separation distance L2 between the point P(t12) and the workpiece W having the outer diameter Db in FIG. 5(b), The separation distance L12 is the same.

That is, the starting positions X2 and X12 of the rough polishing process S3 are set at positions corresponding to the outer diameters Da and Db of the workpiece W so that the distance L2 and the distance L12 are the same. The distance L10 shown in FIGS. 4(b) and 5(b) is shorter than the distance L0 shown in FIGS. 4(a) and 5(a).

In the rough grinding step S3 performed following the air grinding step S2, the moving speed of the grinding wheel is made slower than in the air grinding step S2. However, in this embodiment, when the outer diameter Da of the workpiece W is small as shown in FIG. 4(a), compared to the case where the outer diameter Db of the workpiece W is large as shown in FIG. 4(b). This increases the moving speed of the grinding wheel. In other words, the larger the outer diameter of the workpiece W, the lower the machining efficiency in the rough grinding step S3.

In the rough polishing step S3, as shown in FIG. 3, first, a free running operation S3a is performed (t2→t3, t12→t13). In the idle running operation S3a, the X-axis position of the center Ct of the grinding wheel is moved from the starting positions X2 and X12 where the workpiece W and the grinding wheel are separated from each other, to the workpiece W, and the grinding wheel is moved relatively close to the workpiece W. This is an operation of bringing the object W into contact with the grinding wheel.

In FIGS. 4A and 5A, the idle running operation S3a is an operation in which the X-axis position of the center Ct of the grinding wheel moves from X2 to X3 by a distance L2. When the X-axis position of the center Ct of the grinding wheel is located at X3, the grinding wheel is located at a position indicated by T(t3). At this time, a point P (t3) of the grinding wheel closest to the workpiece W is in contact with the workpiece W. In the case of the outer diameter Da of the workpiece W, in the idle running operation S3a, the X-axis position of the center Ct of the grinding wheel moves from X2 to X3 at a predetermined rough grinding speed.

On the other hand, in FIGS. 4(b) and 5(b), the idle running operation S3a is an operation in which the X-axis position of the center Ct of the grinding wheel moves from X12 to X13 by a distance L12. When the X-axis position of the center Ct of the grinding wheel is located at X13, the grinding wheel is located at a position indicated by T (t13). At this time, a point P (t13) of the grinding wheel closest to the workpiece W is in contact with the workpiece W. Further, the distance L2 and the distance L12 are the same. In the case of the outer diameter Db of the workpiece W, in the idle running operation S3a, the X-axis position of the center Ct of the grinding wheel moves from X12 to X13 at a predetermined rough grinding speed.

In this embodiment, the larger the outer diameter of the workpiece W, the slower the relative movement speed of the grinding wheel in the idle running operation S3a. In other words, the predetermined rough polishing speed for the outer diameter Db of the workpiece W is slower than the predetermined coarse grinding speed for the outer diameter Da of the workpiece W. Since the distance L2 and the distance L12 are the same, the time required for the free running operation S3a is longer for the outer diameter Db of the workpiece W than for the outer diameter Da of the workpiece W. However, the relative moving speed of the grinding wheel in the idle running operation S3a may be the same.

Next, as a rough polishing step S3, a rough polishing operation S3b as one of the actual machining operations is performed following the idle running operation S3a (t3→t4, t13→t14). The rough grinding operation S3b is an operation in which the grinding wheel is moved relative to the workpiece W after the free running operation S3a, and actual machining (actual grinding) is performed on the workpiece W using the grinding wheel. be.

As shown in FIGS. 4(a) and 4(b), in the rough grinding operation S3b, the X-axis position of the center Ct of the grinding wheel moves from X3 to X4 or from X13 to X4 at a predetermined rough grinding speed. . That is, the predetermined rough grinding speed in the rough grinding operation S3b when the outer diameter of the workpiece W is Da is the same speed as the predetermined rough grinding speed in the idle running operation S3a when the outer diameter is Da. Further, the predetermined rough polishing speed in the rough polishing operation S3b when the outer diameter of the workpiece W is Db is the same speed as the predetermined rough polishing speed in the free running operation S3a when the outer diameter is Db. In other words, the relative moving speed between the grinding wheel and the workpiece W is constant from the free running operation S3a to the rough grinding operation S3b.

Here, the start time t12 of the idle running operation S3a and the start time t13 of the rough grinding operation S3b when the outer diameter of the workpiece W is a large value Db are different from the start time t12 of the free running operation S3a when the outer diameter of the workpiece W is a large value Da. The timing is earlier than the start times t2 and t3 in the above case. When the outer diameter of the workpiece W is Db, which is a large value, the relative movement distance of the grinding wheel in the rough grinding operation S3b (X13 →X4) becomes longer.

In this embodiment, the larger the outer diameter of the workpiece W, the slower the relative movement speed of the grinding wheel, that is, the lower the machining efficiency. Therefore, the end time t14 of the rough grinding operation S3b when the outer diameter of the workpiece W is a large value Db is later than the end time t4 when the outer diameter of the workpiece W is a small value Da. It has become. However, the end time of the rough grinding operation S3b changes depending on the relative moving distance of the grinding wheel and the relative moving speed of the grinding wheel in the rough grinding operation S3b.

Next, in the rough grinding operation S3b, when the workpiece W reaches the predetermined rough grinding dimension (when the X-axis position of the grinding wheel reaches X4), as one of the actual machining operations, compared to the rough grinding step S3, Then, a fine polishing step S4 is performed in which the moving speed of the grinding wheel is slowed down (t4→t5, t14→t15). In the fine polishing process S4, the X-axis position of the center Ct of the grinding wheel moves from X4 to X5.

Subsequently, in the fine polishing process S4, when the workpiece W reaches the predetermined fine polishing dimension (when the X-axis position of the grinding wheel reaches X5), the moving speed of the grinding wheel is changed as one of the actual machining operations. A fine polishing step S5 is performed to further slow down the grinding process (t5→t6, t15→t16). In the fine polishing step S5, the X-axis position of the center Ct of the grinding wheel moves from X5 to X6.

Subsequently, in the fine grinding process S5, when the workpiece W reaches a predetermined fine grinding dimension (when the X-axis position of the grinding wheel reaches X6), the movement of the grinding wheel is stopped as one of the actual machining operations. In this state, the spark-out step S6 is performed (t6→t7, t16→t17). In the spark-out step S6, since the grinding wheel is not moved in the X-axis direction, the start position X5 and end position X6 of the X-axis position of the center Ct of the grinding wheel coincide. After completing the spark-out process S6, a fast forward/reverse process S7 is performed (t7→t8, t17→t18).

4. Processing of data processing device 7 Processing of data processing device 7 will be explained with reference to FIGS. 6 to 8. Here, among the processes of the data processing device 7, the processes related to the downstream processing equipment 4 will be explained.

As shown in FIG. 6, the data processing device 7 acquires shape information of the workpiece W from the shape measuring device 3 (S11). Subsequently, the data processing device 7 determines the machining allowance ΔG based on the acquired shape information of the workpiece W (S12). The machining allowance ΔG is obtained from the shape information of the workpiece W and the target shape of the workpiece W.

Subsequently, the data processing device 7 determines machining efficiency based on the shape information of the workpiece W (S13). The data processing device 7 may determine the machining efficiency based on the machining allowance ΔG instead of the shape information of the workpiece W, or may determine the machining efficiency based on the shape information and the machining allowance ΔG. Further, the data processing device 7 may determine whether or not the product is an NG product at the same time as determining the machining efficiency (S13).

The processing in step S13 is classified as shown in FIG. The data processing device 7 stores, for example, a minimum value D1, an intermediate value D2, and a maximum value D3 as predetermined dimensions of the workpiece W in descending order. Further, the data processing device 7 stores, as predetermined values of the machining allowance ΔG of the workpiece W, a minimum value ΔG1, an intermediate value ΔG2, and a maximum value ΔG3 in descending order. However, the number of classifications may be decreased or increased.

If the measured dimension D of the workpiece W is smaller than the minimum value D1, that is, if the machining allowance ΔG is smaller than the minimum value ΔG1, the workpiece W cannot be made to the desired accuracy when machining is performed. There is a possibility that it cannot be done. Therefore, in this case, the target workpiece W is determined as an NG product, especially as a product to be discarded. In this case, the downstream processing equipment 4 does not perform machining on the target workpiece W, but discharges the target workpiece W as an NG product, particularly as a product to be discarded, before machining.

When the measured dimension D of the workpiece W is the same as the minimum value D1 or larger than the minimum value D1, that is, when the machining allowance ΔG is the same as the minimum value ΔG1 or larger than the minimum value ΔG1, the measured dimension D or the machining allowance ΔG The corresponding machining efficiency is determined. The larger the measured dimension D, that is, the larger the machining allowance ΔG, the lower the machining efficiency, and the smaller the measured dimension D, that is, the smaller the machining allowance ΔG, the higher the machining efficiency. The downstream machining equipment 4 will perform machining processing on the target workpiece W at the determined machining efficiency.

Specifically, when the measured dimension D of the workpiece W is the same as the minimum value D1 or larger than the minimum value D1 and smaller than the intermediate value D2, in other words, the machining allowance ΔG is the same as the minimum value ΔG1 or smaller than the minimum value ΔG1. If it is large and smaller than the intermediate value ΔG2, the machining efficiency is determined to be "high". In this case, the downstream machining equipment 4 performs machining processing on the target workpiece W by setting the machining efficiency of the rough grinding operation S3b (shown in FIG. 3) to "high".

When the measured dimension D of the workpiece W is the same as or larger than the intermediate value D2, and smaller than the maximum value D3, that is, when the machining allowance ΔG is the same as or larger than the intermediate value ΔG2, and the maximum If it is smaller than the value ΔG3, the machining efficiency is determined to be “low”. In this case, the downstream machining equipment 4 performs machining processing on the target workpiece W by setting the machining efficiency of the rough grinding operation S3b (shown in FIG. 3) to "low".

When machining allowance ΔG is large (more than intermediate value ΔG2), machining efficiency is lowered than when machining allowance ΔG is small (less than intermediate value ΔG2). The reason for this is that although it is unavoidable that the tool cost increases as the machining allowance ΔG increases, by reducing the tool cost associated with tool modification or tool replacement per unit machining allowance, the overall tool cost can be reduced. This is to suppress the soaring price of If the purpose is to suppress the prolongation of machining time, it is necessary to increase the machining efficiency as the machining allowance ΔG increases. However, in this embodiment, even if the machining time becomes long, the machining efficiency is lowered in order to suppress a rise in the overall tool cost.

When the measured dimension D of the workpiece W is the same as the maximum value D3 or larger than the maximum value D3, that is, when the machining allowance ΔG is the same as or larger than the maximum value ΔG3, the target workpiece W is rejected as an NG product. Or, the machining efficiency is set to "low". If it is determined as an NG product, the downstream processing equipment 4 does not perform machining on the target workpiece W and discharges the target workpiece W as an NG product before machining. The NG product here may be a product to be discarded or a product to be reprocessed by the upstream processing equipment 2. When the machining efficiency is determined to be "low", the downstream machining equipment 4 performs machining processing on the target workpiece W with the machining efficiency of rough grinding operation S3b (shown in FIG. 3) being "low". I will do it.

As shown in FIG. 6, following the determination of machining efficiency or NG products (S13), the start positions X2 and X12 of the idle running operation S3a are determined (S14). The starting positions X2 and X12 of the idle running operation S3a are determined according to the measured dimension D as shape information of the workpiece W, as shown in FIGS. 4 and 5. In other words, the start positions X2 and X12 of the free running motion S3a are determined such that the moving distances L2 and L12 of the free running motion S3a are constant regardless of variations in the measured dimension D of the workpiece W. In the machining process for the target workpiece W, the downstream machining equipment 4 changes to the determined start position X2, X12 of the idle running operation S3a.

Subsequently, the data processing device 7 estimates the machining result of the workpiece W when machining processing is performed in the virtual space based on the shape information of the workpiece W and the determined machining efficiency (S15). At this time, the data processing device 7 can also estimate the machining result of the workpiece W by further using the machine information of the downstream machining equipment 4 and various conditions of machining processing. The estimated machining result includes, for example, the machining accuracy of the workpiece W. Further, the estimated machining result may include the state of the grinding wheel that is the tool T.

Subsequently, the data processing device 7 optimizes the processing conditions in the downstream processing equipment 4 based on the determined processing efficiency and estimated processing results (S16). The data processing device 7 can also optimize processing conditions using a production plan. The optimized processing conditions include processing efficiency, etc.

Subsequently, the data processing device 7 optimizes the timing of tool correction or tool exchange based on the determined machining efficiency and machining allowance ΔG (S17). The data processing device 7 optimizes the timing in consideration of past results of machining processing.

Processing related to tool correction will be explained with reference to FIG. 8. As the grinding wheel, which is the tool T constituting the grinding machine which is the downstream processing equipment 4, repeatedly grinds the workpiece W, the surface of the grinding wheel becomes worn or rough. Deterioration of the surface condition of the tool T such as a grinding wheel causes deterioration of the machining accuracy of the workpiece W, such as deterioration of the surface quality of the workpiece W and generation of a machining-affected layer on the workpiece W.

Therefore, in order to improve the surface condition of the grinding wheel which is the tool T, truing and dressing are performed as a modification of the tool T. Truing is a reshaping operation in which a grinding wheel is molded into a desired shape when it is worn out by grinding. Dressing is a refinishing (sharpening) work that involves adjusting the protruding amount of abrasive grains and creating a cutting edge of the abrasive grains. Dressing is the process of correcting clogged eyes, clogged eyes, spilled eyes, etc. Note that truing and dressing may be performed without any particular distinction.

FIG. 8 shows changes in the tool correction index value with respect to the total value of the machining allowance ΔG of the workpiece W when the machining efficiency is set to three types: "high", "medium", and "low". The tool correction index value increases as the machining process of the workpiece W is performed, and becomes the minimum value as the tool correction is performed. When the tool modification index value reaches Th, tool modification is performed.

The higher the machining efficiency, the shorter the machining time for the target workpiece W, and the lower the machining efficiency, the longer the machining time for the target workpiece W. Further, the higher the machining efficiency is, the worse the machining accuracy of the workpiece W becomes, whereas the lower the machining efficiency is, the better the machining accuracy of the workpiece W is.

The tool correction index value can be, for example, a value corresponding to the surface roughness of the workpiece W. Generally, in the case of grinding using a grinding wheel using super abrasive grains such as CBN abrasive grains, the surface roughness of the workpiece W increases as the workpiece W is machined. In this case, the tool correction index value can be the surface roughness itself. Further, in the case of grinding using a normal grindstone using alumina-based abrasive grains, the surface roughness of the workpiece W becomes smaller as the workpiece W is machined. In this case, the tool modification index value can be the reciprocal of the surface roughness. As described above, the tool correction index value can be set to any value depending on the type of grinding process. Note that in this embodiment, the tool correction index value changes to become larger as the machining process of the workpiece W is performed, but it changes to become smaller as the machining process of the workpiece W is performed. You can also set it to do so.

As shown in FIG. 8, when the machining efficiency indicated by the broken line is "high", the frequency of tool correction is high relative to the total value of the machining allowance ΔG of the workpiece W. The tool correction interval when the machining efficiency is "high" is ΔInt_hi. When the machining efficiency indicated by the one-dot chain line is "low", the frequency of tool correction is low relative to the total value of the machining allowance ΔG of the workpiece W. The tool correction interval when the machining efficiency is "low" is ΔInt_low. ΔInt_low is a longer time than ΔInt_hi.

When the machining efficiency indicated by the two-dot chain line is "medium", the frequency of tool correction for the total value of machining stock ΔG of the workpiece W is lower than when it is "high", and more than when it is "low". It's getting expensive. The tool correction interval when the machining efficiency is "medium" is ΔInt_mid. ΔInt_mid is a longer time than ΔInt_hi and shorter than ΔInt_low. In this way, the tool correction interval is determined based on the machining efficiency and the machining allowance ΔG.

Further, in the tool T such as a grinding wheel, the number of times the tool can be corrected is set to, for example, a predetermined number of times. The tool T that has been modified a predetermined number of times becomes a target for tool replacement. Therefore, the shorter the tool correction interval, the shorter the tool change interval, and the longer the tool correction interval, the longer the tool change interval. In this way, the tool exchange interval is determined based on the machining efficiency and the machining allowance ΔG. There is a relationship that the higher the machining efficiency, the higher the tool cost associated with tool correction or tool replacement.

Subsequently, the data processing device 7 outputs the obtained various information to the downstream processing equipment 4 as command information for the downstream processing equipment 4 (S18). For example, the command information that the data processing device 7 outputs to the downstream machining equipment 4 includes machining efficiency, start positions X2 and X12 of the free running operation S3a, optimized machining conditions, and optimized tool correction or tool exchange timing. Including. However, the command information may include at least the start positions X2 and X12 of the idle running operation S3a. Further, the command information may not include optimized machining conditions, optimized tool correction, or optimized tool exchange timing.

5. Processing of the downstream processing equipment 4 Next, processing of the downstream processing equipment 4 will be described with reference to FIG. 9. Here, processing is particularly related to command information acquired from the data processing device 7.

The downstream processing equipment 4 acquires command information from the data processing device 7 (S21). Subsequently, the downstream processing equipment 4 determines whether the command information is information that makes the target workpiece W an NG product (S22). If the target workpiece W is an NG product (S22: Yes), the downstream processing equipment 4 performs NG product handling (S23). When the target workpiece W is determined to be an NG product and a product to be discarded, the downstream processing equipment 4 does not perform machining processing on the workpiece W and processes it as a product to be discarded. If the target workpiece W is determined to be an NG product and is to be reprocessed by the upstream processing equipment 2, the downstream processing equipment 4 does not perform machining on the target workpiece W. Treat it as a product subject to reprocessing. After dealing with NG products, the process proceeds to step S28, which will be described later.

On the other hand, if the target workpiece W is not an NG product (S22: No), the downstream processing equipment 4 performs machining processing (grinding processing) on the target workpiece W (S24). At this time, the downstream processing equipment 4 performs machining processing based on the start positions X2 and X12 of the free running operation S3a. That is, the downstream machining equipment 4 performs machining processing under the changed machining conditions at the determined starting positions X2 and X12 of the idle running operation S3a. Therefore, the moving distances L2 and L12 of the idle running operation S3a are constant regardless of the workpiece W.

Further, when the command information includes machining efficiency as shown in FIG. 7, the downstream machining equipment 4 performs machining processing using the machining efficiency included in the command information. Furthermore, when the command information includes optimized machining conditions, the downstream processing equipment 4 performs machining processing using the optimized machining conditions included in the command information.

Subsequently, when the downstream machining equipment 4 finishes machining the target workpiece W (S24), it determines whether tool correction or tool replacement is necessary (S25). Specifically, when the command information from the data processing device 7 includes the optimized tool correction or tool exchange timing, the downstream processing equipment 4 changes the current state to the optimized timing. Determine whether it has been reached. If the command information does not include the optimized tool correction or tool exchange timing, the downstream processing equipment 4 determines whether the current state has reached the preset tool correction or tool exchange timing. Determine whether or not.

Subsequently, if it is determined that tool correction or tool exchange is necessary (S26: Yes), the downstream processing equipment 4 executes tool correction or tool exchange (S27). In other words, tool modification or tool exchange is performed at optimized timing. On the other hand, if it is determined that tool correction or tool exchange is not necessary (S27: No), the process proceeds to the next process (S28) without executing tool correction or tool exchange.

Subsequently, the downstream processing equipment 4 determines whether or not there is a next workpiece W (S28), and if there is a next workpiece W (S28: Yes), the process is repeated from step S21. Therefore, optimal machining processing is performed for each workpiece W. If there is no next workpiece W (S28: No), the process ends.

6. Modification The configuration of a production system 1' as a modification of the production system 1 described above will be described with reference to FIG. 10. In the production system 1', the management device 6' may transmit and receive data between the upstream processing equipment 2, the inspection device 5, and the data processing device 7'. In this case, the data processing device 7' will transmit and receive data between the shape measuring device 3 and the downstream processing equipment 4. The functions between the data processing device 7', the shape measuring device 3, and the downstream processing equipment 4 are similar to those described above.

7. Effects The production system 1, 1' of this embodiment includes an upstream processing facility 2 and a downstream processing facility 4. In the downstream machining equipment 4, when machining the workpiece W machined by the upstream machining equipment 2 using the tool T, the actual machining operation is performed after performing the idle running operation S3a. Here, the upstream processing equipment 2 performs processing to change the shape of the workpiece W. Therefore, the actual machining operation in the downstream processing equipment 4 is an operation according to the shape of the workpiece W machined by the upstream processing equipment 2.

Here, the production system 1, 1' includes a shape measuring device 3 and a data processing device 7, 7'. The shape measuring device 3 measures the shape of the workpiece W after processing by the upstream processing equipment 2. The data processing devices 7, 7' acquire the shape information of the workpiece W measured by the shape measurement device 3, and before the downstream processing equipment 4 performs machining processing on the workpiece W to be measured. Command information obtained based on the shape information of the workpiece W is output to the downstream processing equipment 4.

Then, the data processing devices 7, 7' determine the starting positions X2, X12 of the free running motion S3a based on the shape information of the workpiece W so that the moving distances L2, L12 of the free running motion S3a are constant. , the determined start positions X2 and X12 of the idle running operation S3a are outputted to the downstream processing equipment 4 as command information. The downstream processing equipment 4 changes the start positions X2, X12 of the free running operation S3a for the target workpiece W by acquiring command information from the data processing devices 7, 7'. In other words, even if there are variations in the shape of the workpiece W after processing by the upstream processing equipment 2, the moving distances L2 and L12 of the idle running operation S3a in the downstream processing equipment 4 are always constant. Therefore, it is possible to suppress an increase in processing cost due to an increase in the length of the idle running operation S3a. In this way, even if there are variations in the workpiece W, processing costs can be reduced.

Further, the data processing devices 7 and 7' determine machining efficiency according to the shape information of the workpiece W, and output the determined machining efficiency as command information to the downstream machining equipment 4, and the downstream machining equipment 4 A machining process is performed on the target workpiece W using the machining efficiency obtained from the data processing devices 7 and 7'. Therefore, by adjusting the machining efficiency according to the shape of the workpiece W, increase in machining cost can be suppressed.

Here, the larger the machining allowance ΔG is, the higher the tool cost may become. Therefore, the data processing devices 7, 7' lower the machining efficiency as the machining allowance ΔG of the workpiece obtained from the shape information of the workpiece W and the target shape of the workpiece W increases, and the machining efficiency decreases as the machining allowance ΔG decreases. Increase efficiency. In this way, by creating a relationship between machining allowance ΔG and machining efficiency, it is possible to suppress the increase in the cost of tool scraping. However, the relationship between machining allowance ΔG and machining efficiency is not limited to the above case.

More specifically, the higher the machining efficiency is, the higher the tool cost associated with tool correction or tool replacement becomes. , the larger the machining allowance ΔG, the lower the tool cost per unit machining allowance.

In particular, the tool modification or tool change interval is determined based on machining efficiency and machining allowance. By determining the interval between tool corrections or tool exchanges in this manner, a relationship is established in which the higher the machining efficiency, the higher the tool cost associated with tool corrections or tool exchanges.

As an example of a configuration that has a relationship between machining efficiency and tool cost, the production systems 1 and 1' are configured as follows. That is, the data processing devices 7, 7' determine the machining efficiency and machining allowance ΔG based on the shape information of the workpiece W measured by the shape measuring device 3, and adjust the tool based on the determined machining efficiency and machining allowance ΔG. The timing of correction or tool exchange is optimized, and the optimized timing of tool correction or tool exchange is output to the downstream processing equipment 4 as command information. The downstream processing equipment 4 executes tool correction or tool exchange at optimized timing.

Further, when the machining allowance ΔG is smaller than the predetermined minimum value ΔG1, the data processing devices 7, 7' determine the workpiece W as an NG product and a product to be discarded, and the downstream processing equipment 4 W is treated as a product to be discarded without any mechanical processing. By setting the item to be discarded before processing, unnecessary processing by the downstream processing equipment 4 can be suppressed. As a result, overall processing costs can be reduced.

Further, if the machining allowance ΔG is larger than the predetermined maximum value ΔG3, the data processing devices 7, 7' determine the workpiece W as an NG product and a product to be discarded, or decide that the workpiece W is an NG product and The product is determined to be reprocessed by processing equipment 2. In this case, the downstream processing equipment 4 does not perform machining on the target workpiece W, but processes it as an item to be discarded or an item to be reprocessed. By setting the item to be discarded or reprocessed before processing, it is possible to prevent the downstream processing equipment 4 from performing high-load processing. As a result, overall processing costs can be reduced.

Further, the data processing devices 7, 7' determine machining efficiency based on the shape information of the workpiece W measured by the shape measuring device 3, and perform machining processing in the virtual space based on the determined machining efficiency. Estimate the machining result of the workpiece in case, optimize the machining conditions in the downstream machining equipment 4 based on the determined machining efficiency and the estimated machining result, and output the optimized machining conditions to the downstream machining equipment 4 as command information. You can do it like this. In this case, the downstream processing equipment 4 executes the machining process under the optimized processing conditions. In this way, by optimizing the machining conditions in real time, the workpiece W can be machined with higher precision.

Further, the workpiece W has an outer peripheral surface or an inner peripheral surface with a circular cross-sectional shape, and the shape measuring device 3 measures the diameter dimension of the outer peripheral surface or the inner peripheral surface of the workpiece W as the shape of the workpiece W. However, the downstream processing equipment 4 may be a grinder that grinds the outer circumferential surface or inner circumferential surface of the workpiece W using a grinding wheel serving as a tool T. However, the production systems 1, 1' are not limited to this configuration.

1,1' Production system 2 Upstream processing equipment 3 Shape measuring device 4 Downstream processing equipment 7,7' Data processing device W Workpiece T Tool (grinding wheel)
S3a to S6 Machining processing S3a Free running operation S3b to S6 Actual machining operation X2, X12 Starting position of free running operation L2, L12 Travel distance of free running operation

Claims (10)

upstream processing equipment that performs processing on a workpiece to change the shape of the workpiece;
a shape measuring device that measures the shape of the workpiece after being processed by the upstream processing equipment;
downstream processing equipment that performs machining processing using a tool on the workpiece processed by the upstream processing equipment;
The shape information of the workpiece measured by the shape measuring device is acquired, and before the downstream processing equipment performs the machining process on the workpiece to be measured, based on the shape information of the workpiece. a data processing device that outputs the obtained command information to the downstream processing equipment;
Equipped with
The machining process by the downstream processing equipment includes:
A free running operation of bringing the tool into contact with the workpiece by relatively approaching the workpiece from a starting position where the workpiece and the tool are separated from each other at a predetermined speed;
After the idle running operation, the tool is moved relative to the workpiece at the same speed as the predetermined speed in the idle running operation, and actual machining is performed on the workpiece using the tool. Actual machining operation and
including;
The data processing device determines the start position of the free running motion based on the shape information of the workpiece so that the moving distance of the free running motion is constant, and Outputting the start position of as the command information to the downstream processing equipment,
The downstream processing equipment is a production system in which, in the machining process for the target workpiece, the starting position of the idle running operation is changed based on the command information acquired from the data processing device. The data processing device determines machining efficiency according to the shape information of the workpiece, and outputs the determined machining efficiency to the downstream machining equipment as the command information,
The production system according to claim 1, wherein the downstream processing equipment performs the machining process on the target workpiece at the machining efficiency acquired from the data processing device. The data processing device lowers the machining efficiency as the machining allowance of the workpiece obtained from the shape information of the workpiece and the target shape of the workpiece increases, and lowers the machining efficiency as the machining allowance decreases. The production system according to claim 2, wherein the production system is made high. When the machining allowance is smaller than a predetermined minimum value, the data processing device determines the workpiece as an NG product and a product to be discarded,
4. The production system according to claim 3, wherein the downstream processing equipment processes the workpiece as the product to be discarded without performing the machining process on the target workpiece. If the machining allowance is larger than a predetermined maximum value, the data processing device determines the workpiece as an NG item and a product to be discarded, or determines the workpiece as an NG item and reprocesses it by the upstream processing equipment. The product is determined to be subject to
4. The production system according to claim 3, wherein the downstream processing equipment processes the target workpiece as the item to be discarded or the item to be reprocessed without performing the machining process on the target workpiece. The higher the machining efficiency, the higher the tool cost associated with tool correction or tool replacement,
4. The production system according to claim 3, wherein the data processing device lowers the tool cost per unit machining allowance as the machining allowance increases by lowering the machining efficiency as the machining allowance increases. 7. The production system according to claim 6, wherein the tool correction or tool exchange interval is determined based on the machining efficiency and the machining allowance. The data processing device includes:
determining the machining efficiency and the machining allowance based on the shape information of the workpiece measured by the shape measuring device;
optimizing the timing of the tool correction or tool exchange based on the determined machining efficiency and machining allowance;
outputting the optimized timing of the tool correction or the tool exchange to the downstream processing equipment as the command information;
The production system according to claim 7, wherein the downstream processing equipment executes the tool correction or the tool exchange at the optimized timing. The data processing device includes:
determining the machining efficiency based on the shape information of the workpiece measured by the shape measuring device;
Estimating the machining result of the workpiece when the machining process is performed in virtual space based on the determined machining efficiency,
optimizing processing conditions in the downstream processing equipment based on the determined processing efficiency and the estimated processing result;
Outputting the optimized processing conditions as the command information to the downstream processing equipment,
The production system according to claim 2, wherein the downstream processing equipment executes the machining process under the optimized processing conditions. The workpiece has an outer peripheral surface or an inner peripheral surface with a circular cross-sectional shape,
The shape measuring device measures a diameter dimension of the outer peripheral surface or the inner peripheral surface of the workpiece as the shape of the workpiece,
10. The production system according to claim 1, wherein the downstream processing equipment is a grinder that grinds the outer circumferential surface or the inner circumferential surface of the workpiece using a grinding wheel as the tool.

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