JP6772121B2 - Manufacturing method of grinding equipment and metal parts - Google Patents

Description

The present invention relates to a grinding device for accommodating a work group in a plurality of work accommodating holes of a rotary table and passing it between a pair of rotary grindstones for grinding, and a method for manufacturing a metal part using the grinding device.

Conventionally, as a grinding device of this type, there is known a device that inspects the length of a work group while grinding it and finishes grinding when it reaches a preset reference length (see, for example, Patent Document 1). Further, as this type of grinding device, the first and second rotary tables are supported by a movable table, and after grinding the first work group of the first rotary table to the reference length, the movable table is operated to perform the first. A method has also been developed in which the positions of the rotary table and the second rotary table are exchanged to grind the second work group of the second rotary table until the reference length is reached.

Japanese Unexamined Patent Publication No. 2012-035355 (see paragraph [0045])

However, in the grinding apparatus provided with the first and second rotary tables as described above, there is a problem that the variation in the work length becomes large.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a grinding device capable of suppressing variation in work length and improving quality, and a method for manufacturing a metal part using the grinding device.

In order to solve the above problem, the inventor of the present application examined the work length of the work group ground by the grinding apparatus having the first and second rotary tables, and found that the work length was between the first work group and the second work group. Therefore, we obtained the inspection result that there was no big difference in the variation of the work length, and the average of the work length was uniformly deviated. Since the length of the work group was measured based on the position of the upper surface of the work group, the above-mentioned average deviation of the work length is "the first of the movable tables that support the first work group from below at the time of length measurement. It was found that this was caused by the "height difference between the 1 work support part and the 2nd work support part of the movable table that supports the 2nd work group from below at the time of length inspection". In view of this, the inventor of the present application has completed the inventions of claims 1 to 4 below.

That is, in the invention of claim 1 made in order to achieve the above object, a plurality of rotary tables provided with a plurality of work accommodating holes penetrating vertically are rotatably supported by the movable table, and the first rotary table However, a part of the work is rotationally driven while being arranged between the pair of rotary grindstones, and the first work group in the plurality of work accommodating holes of the first rotary table is rotated by the pair. When the work length of the first work group, which is passed between the grindstones and is inspected by the detector based on the upper surface position of the first work group, is ground to a predetermined reference length, the movable table Is activated and a part of the second rotary table is arranged between the pair of rotary grindstones, and the second work group in the plurality of work accommodating holes of the second rotary table is the reference. In a grinding machine that grinds to a long length, the first work support portion of the movable table that supports the first work group from below at the time of length inspection and the first work support portion of the movable table that supports the second work group from below at the time of length inspection. One of the first work group and the second work group is inspected so that the correction value storage unit that stores the height difference between the two work support parts as a correction value and the length measurement error due to the height difference can be suppressed. The grindstone device includes a correction calculation unit that adds or subtracts the correction value to the long result or the reference length.

According to the second aspect of the present invention, a plurality of rotary tables provided with a plurality of work accommodating holes penetrating vertically are rotatably supported by a movable table, and the first rotary table partially forms a pair of rotary grindstones. The first work group in the plurality of work accommodating holes of the first rotary table is passed between the pair of rotary grindstones and is driven to rotate in a state of being arranged between the two. When the work length of the first work group, which is inspected by the detector based on the upper surface position of the one work group, is ground to a predetermined reference length, the movable table is activated to operate the second rotary table. A grinding device is used in which a part is arranged between the pair of rotary grindstones and the second work group in the plurality of work accommodating holes of the second rotary table is ground to the reference length. In a method for manufacturing a metal part by grinding a work to manufacture a metal part, the first work support portion of the movable table that supports the first work group from below at the time of length inspection and the second work group are downward at the time of length inspection. The height difference between the movable table and the second work support portion of the movable table supported from the above is measured in advance, and the first work group or the second work group is supported so that the length measurement error due to the height difference can be suppressed. The height difference is corrected by adding or subtracting the height difference to one of the length inspection results or the reference length, or the height difference between the reference length for the first work group and the reference length for the second work group. This is a method for manufacturing a metal part, in which the deviated value is set separately to manufacture the metal part.

According to the third aspect of the present invention, the master work which is accommodated in a part of the work accommodating holes of the first rotary table and whose first length detection result is obtained by the detector is stopped. housed in a portion of the workpiece housing hole of the rotary table to obtain a second Kencho result by said detector, to claim 2 from which the first and the second Kencho results difference obtaining the height difference The method for manufacturing a metal part according to the description.

In the invention of claim 4 , the first work group and the second work group are ground without the correction until the same reference length is obtained, and the length is measured with the same length detector. The method for manufacturing a metal part according to claim 2 , wherein the height difference is obtained from the difference.

In the grinding apparatus according to claim 1, the first work support portion of the movable table that supports the first work group from below at the time of length inspection and the second work support portion of the movable table that supports the second work group from below at the time of length inspection. The correction value is added to the length measurement result or reference length of either the first work group or the second work group so that the height difference of is stored as a correction value and the length measurement error due to the height difference is suppressed. Since the correction for subtraction is performed, it is possible to suppress the deviation of the average value of the work lengths between the first work group and the second work group. Thereby, the variation in the work length of all the work groups including the first work group and the second work group can be suppressed, and the quality can be improved.

In the method for manufacturing a metal part according to claim 2 , when the work is ground by a grinding device, the first work support portion of a movable table that supports the first work group from below at the time of length inspection and the second work group are length-checked. One of the first work group and the second work group so that the height difference between the movable table supported from below and the second work support portion is measured in advance and the length measurement error due to the height difference can be suppressed. The height difference is added or subtracted from the length inspection result or the reference length, or the reference length for the first work group and the reference length for the second work group are set separately to the values deviated by the height difference. Therefore, the deviation of the average value of the work lengths between the first work group and the second work group can be suppressed. As a result, the variation in the work length of all the work groups including the first work group and the second work group can be suppressed. That is, according to the present invention, it is possible to manufacture high-quality metal parts in which variation in length is suppressed.

The above-mentioned height difference is a part of the second rotary table in the stopped state of the master work which is accommodated in a part of the work accommodating holes of the first rotary table and the first length detection result is obtained by the detector. The second work may be obtained from the difference between the first and second length inspection results by accommodating the work in the work accommodating hole and the detector (invention of claim 3 ), or the first work. The group and the second work group may be ground without correction until they have the same reference length, length-checked with the same length detector, and obtained from the difference between them (invention of claim 4 ). ).

Side view of the grinding apparatus according to the first embodiment of the present invention Cross-sectional view of the grinding device on the BB cut surface of FIG. A cross-sectional view of the subframe and its interior in the AA cut plane of FIG. Partially enlarged side sectional view of the rotary grindstone and rotary table Side sectional view of rotary table and movable table when the workpiece is inspected by the length detector Block diagram of grinding equipment Flow chart of grinding process Flowchart of correction value setting process Flow chart of continuous grinding process Block diagram of grinding equipment Flow chart of continuous grinding process executed by the grinding apparatus according to the second embodiment Flow chart of continuous grinding process executed by the grinding apparatus according to the third embodiment Cross-sectional view of the grinding apparatus according to another embodiment

[First Embodiment]
Hereinafter, an embodiment according to the present invention will be described with reference to FIGS. 1 to 10. As shown in FIG. 1, the grinding device 10 of the present embodiment includes a pair of rotary grindstones 13 and 14 arranged vertically facing each other in a main frame 12 having a vertically long housing structure. Both rotary grindstones 13 and 14 are rotationally driven in the same direction at the same rotational speed, and can be moved to arbitrary positions in the vertical direction, respectively. Further, a front opening 15 is formed in a central portion in the vertical direction on the front surface of the main frame 12.

A subframe 21 is attached to a portion of the front surface of the main frame 12 below the front opening 15 and is supported in a state of floating from the floor surface. Further, a flat plate-shaped fixed support table 25 is stacked and fixed on the upper surface of the subframe 21, and the upper surface of the fixed support table 25 and the upper surface of the lower rotary grindstone 14 are arranged substantially flush with each other. (See FIG. 4).

Further, as shown in FIG. 2, the fixed support table 25 has, for example, an octagonal outer shape in a planar shape, and an arc-shaped notch 25B is formed on one side thereof. A part of the fixed support table 25 is received in the main frame 12, and the inner surface of the notch 25B is arranged so as to face the outer peripheral surface of the lower rotary grindstone 14 with a slight gap. ..

A circular opening 25A is formed in the center of the fixed support table 25, and the circular table body 26H of the movable table 26 is loosely fitted with a slight gap. Further, as shown in FIG. 3, the movable table 26 includes a rotating bar 27 extending in the radial direction of the table body 26H fixed to the lower surface of the table body 26H, and a support table shaft arranged coaxially with the table body 26H. 29 hangs from the rotating bar 27. The support table shaft 29 is rotatably supported by the support beam 22 provided on the subframe 21, and the upper surface of the table body 26H is held so as to be flush with the upper surface of the fixed support table 25. Further, the output shaft 50J of the movable table drive source 50, which is a servomotor attached to the lower surface side of the support beam 22, is connected to the support table shaft 29, and the movable table 26 is positioned and controlled at an arbitrary rotation position. Note that FIG. 3 is a cross-sectional view of the AA cut surface (see FIG. 1) when the movable table 26 is rotated 90 degrees from the state shown in FIG.

Both ends of the rotating bar 27 are provided with a pair of first support holes 30A and 30A that vertically penetrate the rotating bar 27 and the table body 26H together. Further, the rotary table shafts 31 and 32 are rotatably supported in the first support holes 30A and 30A, and project to the upper side and the lower side of the movable table 26. Then, the first rotary table 41A according to the present invention is fixed to the upper part of one rotary table shaft 31, while the second rotary table 41B according to the present invention is fixed to the upper part of the other rotary table shaft 32. There is. Specifically, the first and second rotary tables 41A and 41B have a plurality of work accommodating holes 45 (see FIG. 2) penetrating through the outer edge portion of the disk and having a fitting hole in the central portion. It has a structure. Then, the first and second rotary tables 41A and 41B are fitted and fixed by fitting and fixing the fitting holes at the center to the upper protruding portions of the rotary table shafts 31 and 32, from the upper surfaces of the fixed support table 25 and the movable table 26. It is held in a slightly floating state. In the following description, when the first and second rotary tables 41A and 41B are not distinguished, they are simply referred to as "rotary table 41".

The first and second rotary tables 41A and 41B have the same outer diameter, and the first and second rotary tables 41A and 41B are located at the two positions farthest from each other, except for the portion where the notch 25B is formed. It is sized to fit inside the fixed support table 25. Then, by rotating the movable table 26, a part of any one rotary table 41 can be arranged between the pair of rotary grindstones 13 and 14. Specifically, one of the rotary tables 41 is located on the rotary grindstones 13 and 14 side, and the straight line connecting the rotary center of the rotary table 41 and the rotary grindstones 13 and 14 is arranged at the shortest position. (The position of the rotary table 41 at this time is referred to as a "grinding position"), and a part of the plurality of work accommodating holes 45 of the rotary table 41 can be arranged in the grinding space between the rotary grindstones 13 and 14. Then, the upper surface and the lower surface of the work accommodated in the plurality of work accommodating holes 45 and protruding vertically from the rotary table 41 are ground by the rotary grindstones 13 and 14. Further, in the grinding device 10 of the present embodiment, as shown in FIG. 4, for example, a compression coil spring is housed in the work accommodating hole 45 as the work W, and a pair of rotary grindstones 13 and 14 have a predetermined work length (that is, that is). It is ground to (spring length). The metal work W such as the compression coil spring ground in this way corresponds to the "metal part" of the present invention.

The first and second rotary tables 41A and 41B are rotationally driven by the first and second rotary table drive sources 51 and 52, which are servomotors. Specifically, the first and second rotary table drive sources 51 and 52 are arranged on both sides of the movable table drive source 50 on the lower surface of the support beam 22. Further, the input gear 55 that rotates integrally with the output shaft 51J of the drive source 51 for the first turntable is arranged above the support beam 22, and rotates integrally with the output shaft 52J of the drive source 52 for the second turntable. The input gear 55 is also arranged above the support beam 22. The input gear 55 of the drive source 51 for the first rotary table and the output gear 62 fixed to the lower end of one rotary table shaft 31 include relay gears 57G1 and 57G2 that rotate around the support table shaft 29. The input gear 55 of the drive source 52 for the second rotary table and the output gear 62 fixed to the lower end of the other rotary table shaft 32 are connected via a plurality of relay gears around the support table shaft 29. It is connected via a plurality of relay gears including the rotating relay gears 58G1 and 58G2. As a result, the first rotary table 41A is arbitrarily rotationally driven by the first rotary table drive source 51, and the second rotary table 41B is arbitrarily rotationally driven by the second rotary table drive source 52.

As shown in FIG. 2, the fixed support table 25 is provided with a work discharge port 70 for discharging the work group of the rotary table 41 at a position opposite to the grinding position (hereinafter, referred to as “grinding facing position”). ing. The work discharge port 70 is formed by cutting a part of the fixed support table 25 into a substantially rectangular shape, and is normally closed by a lid body 68 hinged to the opening edge thereof. Further, the upper surface of the lid body 68 and the upper surface of the fixed support table 25 are flush with each other. Then, the lid 68 is opened downward by the air cylinder 69, the work group of the rotary table 41 at the grinding facing position is discharged to the work discharge port 70, and is guided to the work discharge duct 71 provided below the work group. Is housed in the work storage box 72.

As shown in FIG. 1, the grinding device 10 is provided with a detector 65 for measuring the length of the work group of the rotary table 41 at the grinding position. In order to support the detector 65, a first arm 81 extends horizontally forward on one side surface of the main frame 12, and a rotating shaft 83 hangs down from the tip of the first arm 81. A second arm 82 extends horizontally from the lower end of the rotating shaft 83, and a detector 65 is attached to the tip of the second arm 82. Further, the second arm 82 is rotationally driven in a predetermined movable range together with the rotating shaft 83 by an air actuator 85 attached to the upper surface of the first arm 81. Then, when the detector 65 is arranged at the "measurement position" at one end of the movable range, the detector 65 is located above the movable table 26. At the measurement position, the outer edge of the rotary table 41 arranged at the grinding position is located between the detector 65 and the movable table 26, and as shown in FIG. 2, the contact disk 67 described below of the detector 65 Covers a plurality of work accommodating holes 45 (for example, 2 to 3) of the rotary table 41 at the grinding position.

When the movable table 26 rotates, the detector 65 at the measurement position interferes with the upper protruding portions of the rotary table shafts 31 and 32. Therefore, when the movable table 26 rotates, the detector 65 is at the other end of the movable range. It moves to the "interference avoidance position" (not shown) and stands by outside the moving area of the rotary table shafts 31 and 32.

The detector 65 has a rod 66 that can move up and down, and a contact disk 67 is provided at the lower end of the rod 66. As shown in FIG. 5, the outer edge portion of the lower surface of the contact disk 67 is tapered, and the entire lower surface excluding the outer edge portion is a flat surface. Further, the detector 65 is provided with an elevating device (not shown) for moving the contact disk 67 to an arbitrary height. The elevating device restricts the contact disk 67 from moving downward from an arbitrary height position, and allows the contact disk 67 to move upward. Then, the rotary table 41 rotates while the contact disk 67 of the detector 65 arranged at the measurement position covers the plurality of work accommodating holes 45 of the rotary table 41 at the grinding position, so that a pair is formed. The work group that has passed between the rotary grindstones 13 and 14 is sequentially submerged below the contact disk 67, and the axial length of the work group is measured by the amount by which the contact disk 67 is pushed up at that time.

Specifically, as shown in FIGS. 2 and 5, when the first rotary table 41A is located at the grinding position, the contact disk 67 of the detector 65 at the measurement position supports the first work on the upper surface of the movable table 26. The position of the upper surface of the work group located above the portion 26X and whose lower surface is supported by the first work support portion 26X is detected by the detector 65 as a substitute value for the work length. Further, when the second rotary table 41B is located at the grinding position, the contact disk 67 of the detector 65 at the measurement position is the second upper surface of the movable table 26, which is 180 degrees away from the above-mentioned first work support portion 26X. The position of the upper surface of the work group located above the work support portion 26Y (see FIG. 2) and whose lower surface is supported by the second work support portion 26Y is detected by the detector 65 as a substitute value for the work length.

In this way, with respect to the work group of the first turntable 41A (which is simply referred to as the "first work group"), the upper surface position of the first work group with respect to the first work support portion 26X is determined by the detector 65. With respect to the work group of the second turntable 41B (which is simply referred to as "second work group"), the upper surface position of the second work group with reference to the second work support portion 26Y is detected by the detector 65. Therefore, if there is a height difference between the first work support portion 26X and the second work support portion 26Y, the detection result of the detector 65 for the first work group and the detection result of the detector 65 for the second work group There is an error between. In order to correct the error, the grinding device 10 of the present embodiment is provided with a correction calculation unit 73, which will be described in detail later.

As the above-mentioned lifting device of the detector 65, for example, a rod 66 lifted by a balancer is urged downward by an air cylinder or the like to urge the contact disk 67 to the lower end of the vertical movement range. Configuration is mentioned. In such a configuration, the pressing force of the contact disk 67 against the work group can be adjusted by adjusting the urging force of each of the balancer and the air cylinder described above.

As shown in FIG. 6, the controller 89 of the grinding device 10 includes a control unit 94 having a CPU 90, a ROM 91, and a RAM 92 as main parts, a movable table drive source 50, and first and second rotary table drive sources 51. The servo amplifier 96 of 52, the air actuator 85, the valve drive circuit 95 for driving the air cylinder 69, and the like are provided. Then, the CPU 90 executes the grinding process program PG1 (see FIG. 7) stored in the ROM 91, so that the controller 89 functions as a data processing unit 99 including the correction calculation unit 73 (see FIG. 10) described above. , A control signal is output to the servo amplifier 96, the valve drive circuit 95, etc. to control the entire grinding apparatus 10. Further, when the CPU 90 performs each process of the grinding process program PG1, the upper surface position of the work group detected by the detector 65 and the design of the movable table 26 including the first and second work support portions 26X and 26Y Based on the position of the upper surface, the detected value of the detector 65 is converted into the measured length of the work length from the upper surface of the movable table 26 to the lower surface of the contact disk 67 and incorporated into each process. Further, the CPU 90 distinguishes between the first and second rotary tables 41A and 41B, and determines which rotary table 41 is located around the rotary axis of the movable table 26, which is the servomotor described above. Monitoring is performed based on the output of the rotation position sensor of the drive source 50 for the movable table.

Since the upper surface position of the work group detected by the detector 65 is a substitute value for the work length, the detection result of the detector 65 which is not converted into the actual work length can also be detected by the "detector 65" according to the present invention. Corresponds to "long result".

Hereinafter, the grinding process program PG1 will be described. Each time the movable table 26 rotates, the detector 65 moves between the measurement position and the interference avoidance position in order to avoid interference with the rotary table shafts 31 and 32 as described above. In the description, the processing of the rotation operation of the detector 65 is omitted.

As shown in FIG. 7, the grinding process program PG1 is configured so that the input process (S10), the correction value setting process (S11), and the continuous operation process (S12) are executed in order. When the input process (S10) is executed, a message prompting the input for setting the reference length of the work is displayed on the monitor 98 (see FIG. 6) of the controller 89.

On the other hand, when the operator sets and inputs the reference length on the console 97 of the controller 89, the distance between the pair of rotary grindstones 13 and 14 is set to the size corresponding to the reference length, and the pair of rotary grindstones 13 ,. The input process (S10) ends when 14 is rotationally driven to reach a constant rotation speed, and the correction value setting process (S11) is executed.

As shown in FIG. 8, when the correction value setting process (S11) is executed, the first instruction process (S21) is performed. For example, after the work group is accommodated in the rotary table 41 at the grinding facing position, the console 97 A message instructing to turn on the execute button (not shown) is displayed on the monitor 98.

When the operator performs the work and the operation according to this message, the movable table 26 is rotationally driven by 180 degrees, the rotary table 41 accommodating the work group is moved to the grinding position, and grinding is started (S22). .. Then, the length measurement result by the detector 65 of the work group of the rotary table 41 is taken in as the length measurement value, and it is determined whether or not the length measurement value has reached the reference length (NO loop of S23 and S24). ), When the reference length is reached (YES in S24), the movable table 26 is rotated by, for example, 180 degrees, the rotary table 41 that does not contain the work group is moved to the grinding position, and the rotation that contains the ground work group is rotated. The table 41 is moved to the opposite position for grinding (S25).

Then, the second instruction process (S26) is performed, for example, in the rotary table 41 at the grinding position, the rotary table 41 at the grinding facing position is inserted into the three empty work accommodating holes 45 immediately before the detector 65 at the detection position. A message instructing to turn on the execution button after accommodating the ground work group (corresponding to the "master work" of the present invention) as a master piece is displayed on the monitor 98.

When the operator performs the work and the operation according to this message, the rotary table 41 at the grinding position is slightly rotated and then stopped or remains in the rotating state, and the work group as the master piece is inspected by the detector 65. It is lengthened and the length measurement result is taken in as a length measurement value (S27). Then, a value obtained by subtracting the reference length from the measured length value is stored in the RAM 92 as a correction value (S28). Instead of subtracting the reference length, the length measurement value obtained with the master piece housed in the rotary table 41 on which the master piece is created may be subtracted.

Next, a table identification process (S29) is performed, and any of the first and second rotary tables 41A and 41B is used to create the masterpiece, and any rotary table 41 is used to set the correction value. Settings are made to identify whether it has been used. Specifically, a first identifier is attached to the rotary table 41 used for creating the masterpiece, and a second identifier is assigned to the other rotary table 41 used for setting the correction value.

Next, the work collection process (S29) is performed, the work discharge port 70 is opened, the rotary table 41 with the first identifier is rotationally driven, and the work discharge port 70 is closed after the work group is collected. Then, a message instructing to turn on the execution button after accommodating the new work group in the rotary table 41 at the position facing the grinding is displayed on the monitor 98. On the other hand, when the operator performs the work and the operation according to this message, the correction value setting process (S11) is completed, and the continuous operation process (S12) shown in FIG. 9 is executed.

When the continuous operation process (S12) is executed, the movable table 26 is rotationally driven by 180 degrees (S41), grinding of a new work group housed in the rotary table 41 is started, and the length measurement values of those work groups are taken in. (S42). Then, it is determined whether or not the rotary table 41 located at the grinding position is the rotary table 41 with the second identifier, and if it is the rotary table 41 with the second identifier (YES in S43). After the correction of subtracting the correction value from the captured length measurement value is performed (S44), it is determined whether or not the corrected length measurement value has reached the reference length (S45). On the other hand, when the rotary table 41 where the grinding position is located is the rotary table 41 with the first identifier (NO in S43), the captured length measurement value reaches the reference length without performing the correction. It is determined whether or not it has been done (S45). Then, the predetermined steps S42 to S45 described above are repeated until the length inspection value reaches the reference length, and during that time, the workpiece group of the rotary table 41 is ground by the rotary grindstones 13 and 14 (NO loop in S45). ).

In the meantime, the previously ground work group is collected in the work discharge port 70. As a result, the work group as the master piece described above is also collected. Further, while the work group is being ground, a preparation confirmation process (not shown) is executed to accommodate the new work group in the rotary table 41 at the position facing the grinding, and then the execute button is turned on for confirmation. , A message instructing whether to turn on the end button is displayed on the monitor 98. Therefore, if the work and operation corresponding to the operation are performed, the operation is memorized.

When the length measurement value reaches the reference length (YES in S45), the work collection process (S46) is executed, the movable table 26 is rotationally driven by 180 degrees, and the rotary table 41 is replaced. Then, when the execute button is turned on in the preparation confirmation process, the processes of steps S42 to 45 described above are repeated, the ground work group is collected, and the grinding of the work group is newly started. .. On the other hand, when the end button is turned on, only the ground workpiece group is collected, the rotary grindstones 13 and 14 are stopped, and the grinding process program PG1 is terminated (S47).

As described above, in the grinding apparatus 10 of the present embodiment, the first work support portion 26X of the movable table 26 and the second work of the second rotary table 41B that support the first work group of the first rotary table 41A from below at the time of length inspection. The height difference between the movable table 26 and the second work support portion 26Y that supports the group from below at the time of length inspection is stored as a correction value, and the first work group or the first work group or the length difference due to the height difference can be suppressed. Since the correction value is subtracted from the length measurement result of one of the second work groups, it is possible to suppress the deviation of the average value of the work lengths between the first work group and the second work group. Thereby, the variation in the work length of all the work groups including the first work group and the second work group can be suppressed, and the quality can be improved. Further, while grinding the work group of one rotary table 41, the ground work group housed in the other rotary table 41 is collected, or the work group to be ground next is housed in the other rotary table 41. Since it is possible to perform preparations for the above, it is possible to efficiently grind a large number of workpiece groups. Then, by manufacturing a metal part such as a compression coil spring using this grinding device 10, it is possible to manufacture a high-quality metal part in which variation in length is suppressed.

As described above, when the CPU 90 executes the grinding process program PG1, the controller 89 functions as the data processing unit 99 shown in FIG. That is, the data setting unit 74 composed of the CPU 90 when the above steps S10, S27, and S28 are being executed stores the correction value in the correction value storage unit 75 composed of a part of the storage area of the RAM 92. , The reference length is stored in the reference length storage unit 76 composed of the other part of the storage area of the RAM 92. Then, the correction calculation unit 73 configured by executing steps S42 to S44 determines whether or not correction is necessary based on whether or not the rotary table 41 at the grinding position has a second identifier. If necessary, the correction value storage unit 75 is used to correct the length measurement value acquired from the detector 65 and is given to the comparison unit 78. Then, the comparison unit 78 compares the corrected length measurement value acquired by executing steps S45 and S46 with the reference length of the memory stored in the reference length storage unit 76, and the servo amplifier according to the comparison result. 96, a control signal is output to the valve drive circuit 95 and the like (see FIG. 6), the movable table 26 is rotated, and the rotary table 41 at the grinding position is replaced.

[Second Embodiment]
This embodiment is shown in FIG. 11, and only the configuration of the continuous grinding process (S13) in the first embodiment and the grinding process program PG1 is different. In this continuous grinding process (S13), it is determined whether or not a second identifier is attached to the rotary table 41 at the grinding position during grinding of the work group, and if the second identifier is attached (S50). Yes), the correction is performed by adding the correction value to the reference length (S51), and if the second identifier is not attached (NO in S50), the reference length is not corrected. Then, grinding is performed until the length measurement value reaches the reference value (NO loop in S53), and when the length measurement value reaches the reference value (YES in S53), the work recovery process (S46) is performed as in the first embodiment. And so on. Before the work collection process (S46) is executed, the reference length is returned to the value before correction. The configuration of the present embodiment described above also has the same effect as that of the first embodiment.

[Third Embodiment]
This embodiment is shown in FIG. 12, and only the configuration of the grinding process program PG2 differs from that of the first embodiment. When this grinding process program PG2 is executed, the reference value input process (S60) is executed, and the first reference length for the first rotary table 41A and the second reference length for the second rotary table 41B are set. Input is required separately. On the other hand, for example, the second reference length may be set to a value at which the above-mentioned height difference is offset with respect to the first reference length.

Specifically, as described in the first embodiment, for example, master pieces are prepared in advance on the first rotary table 41A, and the length of the master pieces is measured by the detector 65 in a state of being housed in the first rotary table 41A. At the same time, the same master piece is inspected by the detector 65 even when it is housed in the second turntable 41B. Then, the height difference of the second work support portion 26Y with respect to the first work support portion 26X is obtained from the results of both inspections, and the second work support portion 26Y is higher than the first work support portion 26X by the height difference α. For example, the set value of the second reference length is set to the value obtained by adding the height difference α to the set value of the first reference length, and the height difference α of the second work support portion 26Y with respect to the first work support portion 26X. If it is only low, the set value of the second reference length may be set to the value obtained by subtracting the height difference α from the set value of the first reference length. If the height difference can be regarded as 0, the first reference length and the second reference length may be set to the same value.

When both the first reference length and the second reference length are set and input, the first instruction process (S21) described in the first embodiment is executed, and the work group is accommodated in the rotary table 41 at the grinding facing position. A message instructing to turn on the execute button is displayed on the monitor 98.

When the work and operation are performed in accordance with this, the movable table 26 is rotationally driven by 180 degrees (S62), and grinding of the work group is started. Then, when the length measurement value is taken in (S63) and the rotary table 41 at the grinding position is the first rotary table 41A (YES in S64), the length measurement value and the first reference length are compared (S65). If the length measurement value does not reach the first reference length, the length measurement value is taken in and the same process is repeated (YES in S64, NO loop in S65). On the other hand, when the rotary table 41 at the grinding position is the second rotary table 41B (NO in S64), the length measurement value and the second reference length are compared (S66), and the length measurement value becomes the second reference length. If it does not reach, the length measurement value is taken in and the same process is repeated (NO in S64, NO in S66).

Then, when the length measurement value reaches the first reference value (YES in S65) or the length measurement value reaches the second reference value (YES in S66), the work recovery process (S46) is performed in the same manner as in the first embodiment. And so on. In the present embodiment, the control unit 94 corresponds to the "work length setting unit" of the present invention. According to the configuration of the present embodiment described above, the first reference length for the first work group and the second reference length for the second work group can be set separately, so that the first work group can be set separately. There is a length measurement error due to the height difference between the first work support part 26X of the movable table that supports the second work group from below at the time of length inspection and the second work support part 26Y of the movable table that supports the second work group from below at the time of length measurement. It is suppressed, and the deviation of the average value of the work length between the first work group and the second work group can be suppressed. Thereby, the variation in the work length of all the work groups including the first work group and the second work group can be suppressed, and the quality can be improved.

In addition, in order to manufacture two types of products having different workpiece lengths according to the design specifications by using the grinding apparatus of the present embodiment, the first reference length and the second reference length may be set to different values. .. In this case, for example, depending on whether the rotary table 41 of the first and second rotary tables 41A and 41B is arranged at the grinding position before performing step S62 in the above-mentioned grinding process program PG2. Therefore, a program may be set up in which the intervals between the pair of rotary grindstones 13 and 14 are changed to a size suitable for the first reference length or the second reference length. Further, in this case, it is preferable to provide two work discharge ports 70 for the first turntable 41A and for the second turntable 41B so that they can be collected separately.

[Other Embodiments]
The present invention is not limited to the above-described embodiment, and for example, embodiments as described below are also included in the technical scope of the present invention, and various other than the following, as long as the gist is not deviated. It can be changed and implemented.

(1) In the above embodiment, in obtaining the correction value, the first work group and the second work group are not corrected until they have the same reference length (that is, the upper surface position and the first work group of the first work group). Grind with the grinding device 10 (until the top surface position of the two work groups is the same), collect the first work group and the second work group, and measure the length with the same length detector (for example, caliper, ruler, etc.). By doing so, the difference in length may be obtained as the height difference between the first work support portion 26X and the second work support portion 26Y, and this may be used as the correction value.

(2) In the above embodiment, the detector 65 for detecting the length of the work W is a contact type, but may be a non-contact type, for example, an optical sensor. In this case, for example, a non-contact type detector may detect the upper surface position of the first work support portion 26X and the upper surface position of the second work support portion 26Y, and the difference between them may be used as a correction value.

(3) In the above embodiment, the grinding device 10 is provided with two rotary tables 41, but may be provided with three or more rotary tables 41. In this case, for example, one of the plurality of rotary tables 41 is set as the first rotary table 41A, and each work group of the other rotary table 41 is corrected for the first work group as in the above embodiment. You just have to ask. Then, an identifier is assigned to each of the other rotary tables 41, and in the continuous grinding process, a correction value corresponding to the identifier of the rotary table 41 at the grinding position is added or subtracted from the length measurement value or the reference length. And it is sufficient.

(4) In the above embodiment, the work W is not limited to the compression coil spring, and may be cylindrical or tubular.

(5) In the above embodiment, the rotary table at the grinding position is replaced by rotating the movable table 26, but it may be replaced by rotating the rotary table 26.

[Additional Notes]
In the grinding device 10 described above, the contact disk 67 of the detector 65 is fixedly supported above the work accommodating hole 45 of the rotary table 41 at the grinding position as shown by reference numeral 101 or 102 in FIG. By arranging the work group above the table 25, the work support portion that supports the first work group of the first rotary table 41A from below at the time of length inspection and the first work group of the second rotary table 41B are downward at the time of length measurement. The problem according to the present invention may be solved by configuring the work support portion to be the same as the work support portion supported by the above. For that purpose, it is conceivable that the detector 65 described in the above embodiment is downsized, or a part of the main frame 12 is cut off. Further, with such a configuration, the problem of interference between the detector 65 and the upper protruding portions of the rotary table shafts 31 and 32 is solved, and the configuration in which the detector 65 is rotated by the air actuator 85 is eliminated. Can be done. In addition, this configuration may be applied to the configuration of the third embodiment.

In the third embodiment, when the first reference length and the second reference length are set separately, the setting is caused by the height difference between the first work support portion 26X and the second work support portion 26Y. It does not have to be set to correct so as to suppress the long error. Even in this case, by setting the first reference length and the second reference length, respectively, the productivity is improved as compared with the configuration in which the reference length is reset every time the rotary table 41 at the grinding position is replaced. It becomes possible.

The following configuration 1 is also described in the present disclosure, for example.
<Structure 1>
A plurality of rotary tables having a plurality of work accommodating holes penetrating up and down are rotatably supported by the movable table.
The first rotary table is rotationally driven with a part thereof arranged between a pair of rotary grindstones, and the first work group in the plurality of work accommodating holes of the first rotary table is moved. , The work length of the first work group, which is passed between the pair of rotary grindstones and is inspected by the detector based on the upper surface position of the first work group, is ground to a predetermined reference length. Then, the movable table is activated and a part of the second rotary table is arranged between the pair of rotary grindstones, and the second rotary table is placed in the plurality of work accommodating holes of the second rotary table. In a grinding machine in which a work group is ground to the reference length.
A grinding device provided with a work length setting unit capable of separately setting the reference length for the first work group and the reference length for the second work group.
Since the grinding apparatus of configuration 1 is provided with a work length setting unit capable of separately setting the reference length for the first work group and the reference length for the second work group, the first work group and the second work group are provided. It is possible to improve the quality by suppressing the variation in the work length of all the work groups including the group.

10 Grinding device 13, 14 Rotary grindstone 26 Movable table 26X 1st work support 26Y 2nd work support 41 Rotating table 41A 1st rotary table 41B 2nd rotary table 45 Work accommodating hole 65 Detector 73 Correction calculation unit 75 Correction value Storage unit 76 Reference length storage unit 89 Controller 90 CPU
92 RAM
PG1 Grinding program PG2 Grinding program

Claims (4)

A plurality of rotary tables having a plurality of work accommodating holes penetrating up and down are rotatably supported by the movable table.
The first rotary table is rotationally driven with a part thereof arranged between a pair of rotary grindstones, and the first work group in the plurality of work accommodating holes of the first rotary table is moved. , The work length of the first work group, which is passed between the pair of rotary grindstones and is inspected by the detector based on the upper surface position of the first work group, is ground to a predetermined reference length. Then, the movable table is activated and a part of the second rotary table is arranged between the pair of rotary grindstones, and the second rotary table is placed in the plurality of work accommodating holes of the second rotary table. In a grinding machine in which a work group is ground to the reference length.
The height difference between the first work support portion of the movable table that supports the first work group from below during length inspection and the second work support portion of the movable table that supports the second work group from below during length inspection. A correction value storage unit that stores as a correction value,
Correction by adding or subtracting the correction value to the length measurement result of either the first work group or the second work group or the reference length so that the length measurement error due to the height difference can be suppressed. A grinding device including a calculation unit. A plurality of rotary tables having a plurality of work accommodating holes penetrating up and down are rotatably supported by the movable table.
The first rotary table is rotationally driven with a part thereof arranged between a pair of rotary grindstones, and the first work group in the plurality of work accommodating holes of the first rotary table is moved. , The work length of the first work group, which is passed between the pair of rotary grindstones and is inspected by the detector based on the upper surface position of the first work group, is ground to a predetermined reference length. Then, the movable table is activated and a part of the second rotary table is arranged between the pair of rotary grindstones, and the second rotary table is placed in the plurality of work accommodating holes of the second rotary table. In a method for manufacturing a metal part in which a work group is ground to the reference length and a metal part is manufactured by grinding the work.
The height difference between the first work support portion of the movable table that supports the first work group from below during length inspection and the second work support portion of the movable table that supports the second work group from below during length inspection. Measure in advance
In order to suppress the length measurement error caused by the height difference, correction is performed by adding or subtracting the height difference to the length measurement result of one of the first work group or the second work group or the reference length. A method for manufacturing a metal part for manufacturing a metal part by separately setting the reference length for the first work group and the reference length for the second work group to the values deviated by the height difference. The master work, which is accommodated in the work accommodating hole of a part of the first rotary table and obtained the first length detection result by the detector, is the part of the second rotary table in the stopped state. The method for manufacturing a metal part according to claim 2, wherein the metal parts are housed in a work accommodating hole, a second length detection result is obtained by the detector, and the height difference is obtained from the difference between the first and second length measurement results. .. The first work group and the second work group are ground without the correction until they reach the same reference length, and the length is measured with the same length detector. The method for manufacturing a metal part according to claim 2.

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