JPS58186546A - Safety device of numerical control machine tool - Google Patents

Abstract

PURPOSE:To secure safety even when a workpiece and a tool are brought in extremely close vicinity to each other by providing a contact piece which has the run of the periphery of the tool by means of a cylinder of a safety device for a numerical controller preventing collision between the tool and the workpiece. CONSTITUTION:A cylinder device 7 is provided on one side of a main shaft head 1 in parallel with the main shaft. A contact piece 8 provided on the tip of a piston rod 9 of the cylinder device 7 is stopped when a tool 5 in movement contacts the workpiece W. At the time of processing, the piston rod 9 is operated and the contact piece 8 is elevated to avoid its contact with the workpiece W. The contact piece 8 is included in an electrical abnormality detection circuit 12 due to its contact with an obstacle. Said circuit 12 transmits an abnormality detection signal to a temporary stopping means 13 for NC device and an abnormality informing means 14 which is jointly used with the stopping means 13.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a safety device for a numerical control I (hereinafter referred to as NC) machine tool (J).

The NCIC machine is uniquely programmed in γ1 to prevent collisions between the tool and the workpiece during automatic operation, taking into account various originally expected application conditions, and It is also a condition that it must be carried out according to a prescribed format.

However, in the actual workplace, if there are unforeseen changes due to variations in the dimensions of the workpiece or carelessness of set F, collisions between the tool and the workpiece cannot be avoided. Moreover, there is a risk of damaging expensive tools, workpieces, or the machine tool itself.

- Therefore, when programming, to avoid collisions between the tool and the workpiece, we take safety into consideration by moving the T-shell for positioning at a considerable distance from the workpiece, and If a method such as setting the timing of switching from the rapid feed speed to the acceleration TII* at the 9th position is adopted, the wasted time during which no machining work is performed increases, and work efficiency decreases. Moreover, such safety measures cannot necessarily be said to be perfect.

The present invention has been made in view of the above-mentioned points, and in order to prevent accidents caused by collision between the tool and the workpiece, the tool is positioned at the entire tip of the tool with a slight gap between the tool and the workpiece. A contact element that operates integrally is provided, and when the contact element contacts an obstacle while moving, it outputs an electrical abnormality detection signal, thereby temporarily stopping the NC device or notifying an abnormal situation. The purpose of the present invention is to provide a safety device for an NC machine tool.

Hereinafter, a case will be described in which an embodiment of the present invention is applied to a vertical single-axis drilling machine.

1 and 2 show the main parts of a drilling machine, in which 1 is a spindle head and 2 is a table, which are installed in the same machine frame. A II 5 is attached to the lower end of the spindle rotated by a motor 3 in the spindle head 1 via a tool holder 4, and a workpiece W is attached to the table 2 with a clamp 6.

The spindle head 1 is movable relative to the table 2 along three mutually independent axes. That is, the first axis direction is the vertical movement of the spindle head 1, and the second axis direction and the third axis direction are directions perpendicular to the first axis in a plane perpendicular to the first axis.
The direction of the second axis is a movement to the left and right, and the direction of the third axis is a movement to the front and back.

These movements are automatically controlled by a tape recording command inputted to the NC, and the T shell 5 moves to the commanded position and performs an operation operation corresponding to the addition T.

Next, the reference numeral 7 designates a cylinder device which is connected parallel to the main shaft on one side of the main shaft head 1, and the reference numeral 8 designates a contactor with a member 10 mounted at the tip of the piston rod 9 of the cylinder device f7.

The contact 8 is located close to and in front of the tip of the tool 5 when the piston rod 9 is extended, and is located near the tool holder 4 when the piston rod 9 is retracted. Further, as shown in FIG. 3, the contactor 8 forms a gap 11 between it and the T-shell 5, allowing the tool 5 to move in and out freely. This corresponds to the detection of

However, the contactor 8 is incorporated into an electrical abnormality detection circuit 12 when it comes into contact with an obstacle, and this abnormality detection circuit 12 serves as a temporary stop means 13 of the NC device and an abnormality notification means 14 used in conjunction with this. Anomaly detection signals are transmitted to

The cylinder device 7 extends the piston rod 9 and positions the contact 8 at the front of the tool tip when moving the tool 5 for positioning, but there is no movement during the movement, and the tool 5 remains in a predetermined position. Immediately before shifting to , the piston rod 9 is contracted and the contactor 8 is moved out of the working area of the tool 5 to the vicinity of the mounting portion of the tool 5 . The operation control of this ringing device 7 is programmed in the NG tape in advance.

As explained above, the present invention is provided with a contact which is normally located at the front of the tool tip and which moves away near the tool installation part when the tool is in operation, and which outputs an abnormality detection signal when it comes into contact with an obstacle. Since the structure is configured to temporarily stop NO loading and issue an abnormal situation warning in conjunction with this, abnormal situations such as collision with the workpiece can be avoided under any conditions, improving safety. In addition, it is possible to program the appropriate movement of the tool in close proximity to the workpiece in terms of tool movement and operation, eliminating unnecessary movement and greatly improving work efficiency.It also allows automatic control of NC machine tools. In order to make the most of the advantages of machining, the present invention enables a human operator to monitor multiple machines and quickly take measures in the event of the abnormality described above. It is a technical invention that can be implemented easily and inexpensively by just making certain improvements, and can be applied to various NC machine tools, making a great contribution to users.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; Fig. 1 is a front view of the main parts of the machine tool during positioning movement; Fig. 2 is a front view of the main parts of the machine tool when the tool is in operation; FIG. 3 is a plan view of the contactor. DESCRIPTION OF SYMBOLS 1...-Y-axis head, 2... Table, 3... Motor, 4... Tool holder, 5... Tool, 6...
・Clamp, 7...Cylinder device, 8...
Contactor, 9... Piston rod, 10... Mounting member, 11... Gap, 12... Abnormality detection circuit, 13... Temporary stop means, 14... Abnormal situation notification means. Figure 1

Claims (2)

[Claims] (1) The meninges are located at the front of the tool tip, and the tool operation guard is located at the front of the tool tip.
Attach the contactor that is retracted near the mounting neck to the single-axis head.
ζ Attached to the telescopic support device, when the contact comes into contact with an obstacle during positioning movement, an abnormality detection signal is transmitted to the temporary stop means of the numerical control device, the abnormal situation notification means using Jj and this and 41. A safety device for a numerically controlled machine tool, characterized by being incorporated into an abnormality detection circuit. (2) The safety device in the numerically controlled machine tool according to claim 1, wherein the contactor is formed in an annular shape with a gap between it and the tool.