JP3121700B2 - Numerical control unit with tool life management function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Industrial application] Checking tool life time
The present invention relates to a numerical control device having a tool life management function for automatically changing tools.

[0002]

2. Description of the Related Art In a conventional numerical control apparatus having a tool life management function, a plurality of tools of the same type are mounted in advance in a tool magazine of a machine tool. Checks the tool life time at the time of selection command and automatically selects available tools from the above tool magazine, or suspends machining operation immediately when the used tool reaches the set tool life time Then, the interruption position is stored, and a tool exchange subprogram stored in advance is called and executed to exchange the tool with another tool of the same type.

FIG. 5 is a block diagram showing an example of a conventional numerical control device having a tool life management function. In FIG. 5, an input unit 1 is an input unit for inputting a program command such as a tool selection command. The unit 2 includes a storage unit (hereinafter, referred to as a tool command number storage unit) 2a for storing a tool command number input through the input unit 1, and a storage unit (hereinafter, tool magazine) for storing tool magazine numbers of usable tools. A storage unit (described as a number storage unit) 2b, a storage unit that stores a position when the remaining tool life time of the tool being used becomes 0 (hereinafter referred to as a tool remaining life 0 position storage unit) 2c, and a process executed next. Storage unit for storing block numbers (hereinafter referred to as next block number storage unit)
2d and a storage unit (hereinafter referred to as a tool replacement subprogram storage unit) 2e for storing a tool replacement subprogram.

A tool management data setting unit 10 is a tool management data setting unit in which management data of a tool command number corresponding to a tool magazine number and remaining tool life data for counting a tool life time are set and registered. The tool magazine number output unit 7 is a tool magazine number storage unit 2 b of the storage unit 2.
In the tool magazine number output unit that outputs the tool magazine number stored in the storage unit, the calculation unit 6 includes a calculation unit that selects an available tool magazine number, and a tool correction number management data and a tool correction amount management data. And a calculation unit for determining the selected tool correction number or tool correction amount.
The control unit 5 is a control unit that controls input, storage, calculation, and output operations. The machine tool 8 includes a tool selection unit 8a for selecting a tool and a tool 8b selected by the tool selection unit 8a.

Next, the operation will be described with reference to FIG.
When the operator sets a tool command number and a tool life time corresponding to the tool magazine number using a panel keyboard or the like, the management data TD1 and the tool life time of the tool command number corresponding to the tool magazine number are stored in the tool management data setting unit 10. The remaining tool life data TD2 to be counted is registered. When a tool selection command TS (T code command by a machining program) is input from the input unit 1, the control unit 5 stores the tool command number TSa specified by the tool selection command TS from the input unit 1 in the storage unit 2. Stored in the tool command number storage unit 2a,
Further, using the operation unit 6, using the management data TD1 of the tool command number corresponding to the tool magazine number of the tool management data setting unit 10, the remaining tool life data TD2, and the contents TSa of the tool command number storage unit 2a, the usable tools. The magazine number TMb is determined and stored in the tool magazine number storage section 2 b of the storage section 2, and the tool magazine number TMb is output to the machine tool 8 via the tool magazine number output section 7. In parallel with the above control, the arithmetic unit 6 determines the newly selected tool correction number using the tool correction number management data, the tool correction amount management data, and the content TMb of the tool magazine number storage unit 2b of the storage unit 2. And tool compensation amount TCD
To determine. When executing the tool correction, the control unit 5 performs a correction suitable for a newly selected tool based on the tool correction amount TCD, and operates with the new correction.

Further, during the above operation, the tool life data TD2 of the tool management data setting unit 10 is always checked, and when the tool life data of the tool being used becomes 0 (when the tool life is reached), it is immediately determined. The operation of the machining in the machine tool 8 is temporarily interrupted through the control unit 5, and the interruption position data SDc indicating the position of the tool at the time of the interruption and the block number SDd of the machining program to be executed next are stored in the tool of the storage unit 2. Remaining life 0 position storage unit 2c and next block number storage unit 2
d, respectively. Then, by calling and executing the tool exchange subprogram PDe stored in advance in the tool exchange subprogram storage unit 2e of the storage unit 2, even if the tool selection command TS from the machining program is not input, the currently used tool exchange subprogram PDe is used. As soon as the tool reaches the set tool life, machining is interrupted and the tool is automatically changed.

The following operation is performed in the tool change subprogram PDe. First, the tool that has reached the tool life is returned to the tool change position, the tool is replaced with a usable tool of the same kind, and the tool is corrected for a new tool. The new tool is returned to the machining interruption position in accordance with the interruption position data SDc stored in the CPU, and the remaining command of the machining interruption block is calculated by using the machining interruption position coordinates, the end point coordinates of the interruption block, and the interpolation mode. , And then returns to the next block where the machining program under machining is interrupted in accordance with the block number SDd stored in the next block number storage unit 2d of the storage unit 2.

[0008]

However, in the prior art as described above, if the workpiece is being cut, the workpiece cutting surface at the machining interruption position for tool exchange and the machining restart position after tool exchange is placed on the workpiece cutting surface. There was a problem that a cutter mark was attached. The present invention has been made in view of the above problems, and an object of the present invention is to provide a tool life management function that does not adversely affect a workpiece cutting surface during automatic tool change by checking a tool life time. An object of the present invention is to provide a numerical control device provided with the same.

[0009]

According to the present invention, a tool life time set for each tool is generally set as a standard value,
In view of the points is not enough urgency say shall immediately tool change reaches the tool life time, with a signal contact sensor for detecting contact command or a workpiece and a tool from the machining program, operation with a machining program During ~
The workpiece and the tool that cuts the workpiece
Detecting means for detecting have non-cutting state, when the non-cutting state detected by the detecting means checks the tool remaining life time of the tool in use, operation interrupt position its position when I reach the tool life time storage means for storing as is achieved by having a program switching control means for switching between the machining program and the tool change subprogram.

[0010]

According to the numerical controller having the tool life management function of the present invention, the non-cutting state during the machining operation is detected, and the tool life time of the tool in use in the non-cutting state is checked. As long as the tool life is reached, the tool is changed when the machine is in the non-cutting state. The tool change is performed when it becomes.

[0011]

FIG. 1 is a block diagram showing an example of a numerical control apparatus having a tool life management function according to the present invention. In the non-cutting state detection unit 3, the machining program command data from the input unit 1 or the currently selected tool 8
Using the contact state confirmation signal obtained from the contact sensor of the contact detection unit 8c for detecting whether or not b is in contact with the workpiece through the signal input unit 9, the non-cutting state during operation by the machining program is determined. To detect. In the non-cutting state detected by the non-cutting state detecting unit 3, the program switching control unit 4 checks the tool life time of the tool being used, and continues the operation according to the machining program command, or executes the subroutine for tool exchange. After executing the tool change subprogram, the operation according to the machining program command is switched and executed.

The storage unit 2 stores a tool command number input through the input unit 1 (hereinafter referred to as a tool command number storage unit) 2a, and a storage unit for storing a tool magazine number of a usable tool. (Hereinafter referred to as a tool magazine number storage unit) 2b and a storage unit for storing a tool exchange subprogram (hereinafter referred to as a tool exchange subprogram storage unit) 2
e, a storage unit for storing the contents of the interrupted block of the machining program interrupted for performing the tool change (hereinafter referred to as a machining interrupted block content storage unit) 2f, and a memory for storing the coordinate values interrupted for performing the tool change. (Hereinafter referred to as a machining interruption position storage unit) 2g.

Next, the operation will be described with reference to FIG.
When a tool selection command TS (T code command by a machining program) is input from the input unit 1, the tool selection command TS
Performs a series of tool changing operations. Note that a series of tool change operations when a tool selection command TS is input from the machining program is the same as the operation based on the conventional tool selection command, and a description thereof will be omitted. The non-cutting state detection unit 3 receives the processing program command from the input unit 1
Before executing the operation based on the block data PB, check the contents instructed in the block, or check whether the tool in use is in contact with the workpiece,
It detects whether or not the current state is a state that is not directly related to the cutting of the machined surface (non-cutting state). If the current state is a non-cutting state, the state data STD is sent to the program switching control unit 4. The contact state between the tool and the workpiece is checked based on a contact state confirmation signal CTS obtained from the contact sensor of the contact detection section 8c through the signal input section 9.

The program switching control unit 4 receives the state data STD indicating the non-cutting state, checks the tool remaining life data TD2 of the tool management data setting unit 10, and
If the remaining tool life data of the tool being used is 0, one block data PB of the machining program command from the input unit 1 which has been interrupted for the detection of the non-cutting state is stored in the machining interrupted block content storage unit 2f. The stored coordinate values are stored in the machining interruption position storage unit 2g as machining interruption coordinate positions SPg, and the tool exchange subprogram PDe previously stored in the storage unit 2e is called into the operation memory, and this tool exchange is performed. By executing the subprogram PDe, the tool is changed from the non-cutting state. After the completion of the tool exchange by executing the tool exchange subprogram PDe, the execution is interrupted for the tool exchange, and the interrupted block data PB of the machining program stored in the interrupted block content storage unit 2f is called into the operation memory. By executing, the operation according to the machining program is restarted.

Next, the operation of the non-cutting state detecting section 3 and the program switching control section 4 will be described with reference to the flowchart of FIG. One block data of the machining program command is read, and before executing the block, it is checked whether it is a program end command (M02 command or the like) (step S1). If it is a program end command, the process proceeds to step S6. If it is not a program end command, it is checked whether there is a tool selection command (T code command by a machining program) (step S2). If there is a tool selection command, the process proceeds to step S6. Subsequently, a non-cutting operation command (eg, a positioning operation command based on a G00 command), a non-cutting state specifying command for specifying a predetermined non-cutting area (eg, an M code command), or the currently selected tool 8b is processed. A contact state confirmation signal obtained through the signal input unit 9 from the contact sensor of the contact detection unit 8c that detects whether or not the object is in contact with the object is checked (step S3,
S4, S5), a non-cutting state during operation according to the machining program is detected. Here, the non-cutting state means that the one block data of the read machining program command is the non-cutting operation command or the non-cutting state designation command, or the contact state confirmation signal obtained through the signal input unit 9 is off.
Means the case.

If it is determined in steps S3, S4, and S5 that the tool is not in the non-cutting state, the process proceeds to step S6. If it is determined that the tool is in the non-cutting state, the tool management data setting unit 10 checks the remaining tool life data (step S6). S7) If the remaining tool life data in use is 0 (the tool in use is the life of the tool), the processing from step S8 is performed to perform tool exchange. In step S6, one block data of the machining program command read through the input unit 1 is put into the operation memory as it is, and the operation of the block command is executed. In step S8, in order to interrupt the operation of the tool exchange subprogram, the current block command of the machining program for interrupting the operation by the block command and the interrupted coordinate value are stored in the processing interrupted block content through the control unit 5, respectively. The unit 2f stores the information in the machining interruption position storage unit 2g.

Thereafter, the tool exchange subprogram stored in advance in the tool exchange subprogram storage unit 2e is called out to the operation memory and executed (step S9), and the completion of tool exchange by execution of the tool exchange subprogram is waited. (Step S10) When the tool change is completed, the interrupted block command is read out from the machining interrupted block position storage unit 2f through the control unit 5, the block command is recalled to the operation memory and executed, and all the processes are ended. (Step S11). Thus, 1 of the machining program
Before reading the block data and executing the operation based on the one block data, the non-cutting state detection check and the remaining tool life data check are performed, and the tool change operation by the tool change subprogram is interrupted based on the check result. Thus, even if the tool selection command from the machining program is not input, the tool is automatically changed at the first non-cutting state after the used tool reaches the tool life.

Next, the operation of the tool change subprogram will be described with reference to the flowchart of FIG. The operation of the tool change subprogram is as follows. First, the tool whose tool life has been reached is returned to the tool change position (step S12), and the available tool of the same type as the tool is changed (step S1).
3) The tool is corrected for a new tool, and the new tool is returned to the machining restart position using the data (coordinate position where the machining was interrupted for the tool change) in the machining interrupted position storage unit 2g, and all the processing is performed. The process ends (step S14).

FIG. 4 shows the position at which the tool change subprogram is interrupted during operation by the machining program.
This is supplemented by using the machining program example. In the machining program example of FIG. 4, XP1,..., XP4, YP1,.
4 is a command position of the X axis and the Y axis, G00 is a positioning operation command, G01 is a cutting feed operation command, Fn is a cutting feed speed command, N10... N24 is a sequence number, and Tn is a tool selection command. It should be noted that the tool No. 1 and the tool No. 2 are set / registered in advance as the same type of tool, and the tool magazine No. 1 has the tool No. 1 and the tool magazine No. 2
It is assumed that the tool with the tool number 2 is set / registered as the tool number, and the tool with the tool number 1 is selected first by the tool selection command Tn in this example. Also, tool number 1
The following description will be given as an example on the assumption that the tool number 2 is preset and registered as the same kind of tool as the tool number 2 and has not reached the tool life.

The tool number 1 is selected by the tool selection command Tn of N10, and the tool number 1 which is currently in use during the operation of the tool based on the machining program command and the cutting by the cutting feed operation command of N21. When the tool remaining life time of the numbered tool becomes 0 (the tool life has been reached), machining by that tool is continued until the operation according to the command of N22 is completed. After the operation by the command of N22 is completed, the non-cutting state is detected (in this example, the non-cutting state is detected by the G00 command of the block of N23) before the command of the block of N23 is read and the operation based on the command of the block is executed. Since the currently used tool with the tool number 1 is the tool life, the coordinate position (XP
2, YP2) and the block command of N23.

Before executing the operation according to the block command of N23, a tool exchange subprogram stored in advance is interrupted, and the tool exchange subprogram causes the same type of usable tool number 2 from the tool number 1 tool. The tool is replaced with the tool No. 2, the tool correction of the tool No. 2 is performed, and the newly selected tool No. 2 is set as the operation completion coordinate position (XP2, Return to YP2). When the tool exchange by the tool exchange subprogram is completed, the block command of N23 stored as the machining interrupted block is read and executed, and thereafter, the operation according to the machining program command from N24 is restarted.

[0022]

As described above, according to the numerical controller having the tool life management function of the present invention, the cutting is interrupted even if the tool in use reaches the tool life time during the cutting of the workpiece. Since the tool is changed when the machine is in the non-cutting state, the tool can be changed without affecting the machined surface.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a numerical control device having a tool life management function according to the present invention.

FIG. 2 is a flowchart illustrating an operation example of a non-cutting state detection method and program switching control by the device of the present invention.

FIG. 3 is a flowchart showing an operation example of a tool changing subprogram in the apparatus of the present invention.

FIG. 4 is an example of a machining program for explaining details of program switching control by the apparatus of the present invention.

FIG. 5 is a block diagram showing an example of a conventional numerical controller having a tool life management function.

[Explanation of symbols]

 2f Processing interruption block content storage unit 2g Processing interruption position storage unit 3 Non-cutting state detection unit 4 Program switching control unit 8c Contact detection unit 9 Signal input unit

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B23Q 17/09 B23Q 3/155

Claims (4)

(57) [Claims] 1. Checking the remaining tool life of a tool in use during operation of a machine tool, the tool can be used with the same type of tool as the tool in use, which is previously mounted on a tool magazine of the machine tool. In a numerical control device having a tool life management function for automatically selecting a tool from a tool magazine of the machine tool, a workpiece is controlled during operation by a machining program.
And a detecting means for detecting a non-cutting state in which the tool for cutting the workpiece is not in contact with the tool, and checking the remaining tool life time of the tool in use when in the non-cutting state detected by the detecting means, comprising storage means for storing the position when I reach the tool life time as operation interrupt position, the tool life management function, characterized by comprising a program switching control means for switching between the machining program and the tool change subprogram Numerical control device. 2. The non-cutting state detection by the detection means,
The numerical controller according to claim 1, wherein the numerical control is performed based on a non-cutting operation command in a machining program. 3. The non-cutting state detected by the detecting means is as follows:
2. The numerical control device having a tool life management function according to claim 1, wherein a specific command determined in advance as a non-cutting state designation command is added to a machining program, and the command is performed based on the command. 4. The non-cutting state detection by the detection means,
2. The numerical controller according to claim 1, wherein the numerical control is performed based on a signal of a contact sensor provided in the machine tool for detecting contact between a workpiece and a tool.