JP2818452B2 - Processing abnormality detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Field of Industrial Application) The present invention relates to a machining abnormality detection device that detects an abnormality during machining in a tapping machine that performs tapping on a work.

(Prior art) Conventionally, abnormality detection during tapping, for example, overload detection,
In order to detect whether there is no pilot hole or tap in the work,
Axial load sensors or torque sensors have been used.

(Problems to be Solved by the Invention) The use of such a sensor has the following problems.

 Its configuration is complicated.

 It is difficult to reduce the size due to large size.

Only one abnormality can be detected by one sensor, and various types of abnormality detection require various types of sensors.

 Therefore, high costs are inevitable.

And so on.

An object of the present invention is to provide a machining abnormality detection device that has a simple configuration and can easily detect various types of abnormalities in order to improve the above problem.

[Structure of the Invention] (Means for Solving the Problems) In view of the conventional problems as described above, the present invention allows a tap moving rod to be rotatable within a first cylinder rod provided in a fast-forward cylinder so as to be able to move back and forth. And a tap is provided at the distal end of the tap moving rod, and the distal end of the gear rod and the rear end of the tap moving rod are provided so as to be movable forward and backward and rotatable relative to the first cylinder rod. And a second cylinder rod for forward and reverse rotation of a gear threadedly engaged with a gear provided at a rear end of the gear rod can be moved forward and backward. Provide a lead feed cylinder prepared for
A first detector for detecting a retreat end of the first cylinder rod and a second detector for detecting a forward end are provided, and a third detector for detecting a retreat end of the second cylinder rod and a forward end are detected. In a machining abnormality detection device provided with a fourth detector, when the fourth detector is not turned on within a set time after the tapping is started by advancing the fast-forward cylinder, it is assumed that an overload has occurred. , The fourth
When the second detector is switched from on to off before the detector is turned on, it is assumed that there is no pilot hole for tapping, and the fourth detector is turned on earlier than a predetermined time after starting tapping. In this case, a tap breakage is detected when the tap is broken, and a processing abnormality of the tap is detected.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic configuration diagram of a processing abnormality detection device according to an embodiment of the present invention. The processing abnormality detection device 1 mainly includes a processing machine main body 3, a fast-feed cylinder 5, a lead-feed cylinder 7, and a compressed air control device 9.

Inside the processing machine main body 3, there is provided a set of fast-forward backward and forward end limit switches LS1, LS2 as a first detecting member.
And a set of lead feed retreat end and forward end limit switches LS3, LS4 as a second detection member.

The fast-forward cylinder 5 mainly includes the first cylinder body 11.
, A first cylinder rod 13, a tap moving rod 15,
It consists of a gear rod 17 and a cam rod 19 as rotating rods. The first cylinder body 11 is mounted on the processing machine body 3, and the first cylinder rod 13 is attached to the first cylinder body 11.
Is moved forward and backward by switching compressed air as a fluid, for example.

Further, a tap 21 is provided at the tip of the tap moving rod 15, and the tap moving rod 15 reciprocates while rotating while being screwed with a master screw 23 provided at the tip of the first cylinder rod 13.

One end of the gear rod 17 is a gear 25, and the other end transmits rotation to the other end of the tap moving rod 15, and an engaging portion that allows the tap moving rod 15 to move forward and backward, in this embodiment, a spline connection. Section 27.

Further, a cam rod 19 is provided at the rear end of the first cylinder rod 13 and has two cams 29A and 2A as second detected members that actuate the fast forward retreat end and forward end limit switches LS1 and LS2 as first detected members. 29B is provided.

The lead feed cylinder 7 mainly includes a second cylinder main body 31, a second cylinder rod 33, a ball screw 35 as a transmission member, and a cam rod 37. Second
The cylinder main body 31 is mounted on the processing machine main body 3, and the second cylinder rod 33 moves forward and backward within the second cylinder main body 31 by switching the compressed air.

Also, one end of the ball screw 35 has a second cylinder rod 33.
A gear 41 is screwed to a nut member 39 fixed inside the gear wheel, and the other end is meshed with the gear 25 of the gear rod 17. Reverse rotation.

The cam rod 37 is provided at the front end of the second cylinder rod 33, and is used to actuate the lead feed retreat end and forward end limit switches LS3, LS4 as a second detection member.
Two cams 43A and 43B are provided as detected members.

The compressed air control device 9 supplies compressed air from the air source 45 to the fast-forward cylinder 5 through a so-called air three-point set 47 including a drain pot, a pressure control valve, and a filter. Solenoid valve 49 with SOL1 and air control valve 51 for forward / reverse speed control
A, 51B and check valves 53A, 53B are provided. The air pipe for supplying air to the lead feed cylinder 7 side is provided with a solenoid valve 55 having SOL2, air control valves 57A and 57B for forward and backward speed control, and check valves 59A and 59B. A pressure reducing valve 61 is provided on the retreat speed side, and the read speed during retreat is appropriately reduced.

Table 1 shows that, in order to perform tapping on a workpiece, the operation of the fast-forward cylinder 5 that rapidly returns from the original position to the original position after rapid traverse from the original position to the original position, and rotates forward when the original position is reached. The operation of the lead feed cylinder 7 which performs tapping and reverses to return to the processing position upon completion of the processing is displayed.

Next, FIG. 2 shows a time chart at the time of normal processing according to FIG. The SOL1 of the rapid traverse solenoid valve 49 turns on and starts machining. At this time, fast-forward backward end limit switch LS1
Is switched from on to off, the fast-forward cylinder 5 advances, and when a predetermined time has elapsed, the fast-forward advance end switch LS2
Is turned on, the SOL2 of the lead feed solenoid valve 55 is also turned on, and the lead feed cylinder 7 advances with the advance of the rapid feed cylinder 5 (lead feed backward end LS3 is turned off), and the gear rod 17
Is rotated forward to perform lead feed, and tapping is started. Thereafter, the lead feed advance end switch LS4 is turned on, at the same time, the SOL2 of the lead feed solenoid valve 55 is turned off, the lead feed cylinder 7 starts retreating, the gear rod 17 is rotated in the reverse direction, and the lead feed advance end switch LS4 is turned off. When the tapping is completed. Furthermore, the lead feed cylinder 7
When the lead feed backward end switch LS3 is turned on again, the SOL1 of the fast-forward solenoid valve 49 is switched from on to off, and the fast-forward advance end switch LS2 is turned on by returning the fast-forward cylinder 5 to the machining start position. The switch LS1 is switched from off to on, and from the off position to the off position.

Next, FIG. 3 shows a time chart when a torque equal to or more than a predetermined torque is generated in the tapping processing in FIG. An overload monitoring timer 63 is provided in the processing abnormality detection device 1, and within a predetermined time from the start of tapping when the SOL1 of the fast-forward solenoid valve 49 is turned on, the lead feed advance end switch LS4
Is not turned on, it can be considered that an overload has occurred, the rotation of the gear rod 17 has stopped, and the advance of the lead feed cylinder 7 has been prevented.

Next, FIG. 4 shows a time chart when the work to be tapped has no pilot hole. The rotation of the tap 21 is given by the lead feed cylinder 7 via the gear rod 17, and the lead is advanced by the master screw 23 to feed the lead. However, the tap 23 hits against the work surface and stops, and the cylinder rod 13 of the rapid feed cylinder 5 is stopped. Is pushed back, and before the forward end switch LS4 is turned on, the rapid forward end switch LS2 is turned on.
Is switched from on to off. This switching time can be detected by detecting an alarm.

Next, FIG. 5 shows a time chart in the case of detecting a tap break or the like in tap processing. The processing abnormality detecting device 1 is provided with a monitoring timer 65 for the absence of a tub, which monitors the time from the processing start time, and uses the lead feed forward end switch LS.
4 turns on earlier than the specified time, and S of lead feed solenoid valve 55
It can be detected by detecting the time when OL2 is turned off.

The present invention is not limited to the above-described embodiment, but can be embodied in other forms by making appropriate changes. In the present embodiment, the compressed air is described as the fluid, but pressure oil may be used.

[Effects of the Invention] As can be understood from the above description of the embodiment, in short, the present invention provides a tap moving rod (13) provided in a first cylinder rod (13) provided in a fast-forward cylinder (5) so as to be able to move back and forth. 15) is rotatably screwed and a tap (21) is provided at the tip of the tap moving rod (15), and is provided so as to be able to move back and forth relative to the first cylinder rod (13) and to be rotatable. The tip of the gear rod (17) and the rear end of the tapping rod (15) are connected by a spline joint (27).
And a second cylinder rod () for forward and reverse rotation of a gear (41) screwed with a gear (25) provided at the rear end of the gear rod (17). 33)
And a first detector (LS1) for detecting the retreating end of the first cylinder rod (13) and a second detector (LS1) for detecting the reciprocating end of the first cylinder rod (13).
2) is provided, and a third detector (LS3) for detecting a retreat end of the second cylinder rod (33) and a fourth detector (LS4) for detecting a forward end are provided. If the fourth detector (LS4) is not turned on within a set time after the tapping is started by advancing the rapid feed cylinder (5), it is assumed that an overload has occurred and the fourth detector (LS4) ) Is turned on before the second detector (LS2) is turned on, it is assumed that there is no pilot hole for tapping, and the fourth detector is earlier than a predetermined time after the tapping is started. When (LS4) is turned on, the tap breakage is detected as a tap breakage, and the tap processing abnormality is detected.

As is apparent from the above configuration, in the present invention, the fast-feed cylinder 5 for fast-forwarding the tap 21 and the lead-feed cylinder 7 for rotating the tap 21 and feeding the lead 21 are provided. First and second detectors LS1 and LS2 for detecting a retreat end and a forward end of the first cylinder rod 13, and third and third detectors for detecting a retreat end and a forward end of the second cylinder rod 33 of the lead feeding cylinder 7. Four detectors LS3 and LS4 are provided.

The first, second, third, and fourth detectors LS1, LS2, LS3,
It is configured to detect the occurrence of overload during tapping, no pilot hole, and abnormal machining of tap breakage depending on the ON / OFF operating conditions of LS4.

Therefore, according to the present invention, it is possible to detect the above three types of processing abnormalities at the time of tapping.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a machining abnormality detecting device according to one embodiment of the present invention, FIG. 2 is a time chart at the time of normal machining according to FIG. 1, and FIG. FIG. 4 is a time chart when the work to be tapped does not have a pilot hole, and FIG. 5 is a time chart when a tap break or the like in the tapping is detected. . 1 ... processing abnormality detection device 3 ... processing machine body 5 ... cylinder for rapid feed 7 ... cylinder for lead feed 13,33 ... cylinder rod 15 ... tapping moving rod 17 ... gear rod 19, 37 ... cam rod 21… Tap 23… Master screw 36… Ball screw 39… Nut member LS1, LS2… Rapid feed backward end, forward end limit switch LS3, LS4… Lead feed backward end, forward end limit switch SOL1… Fast forward electromagnetic Valve SOL2 …… Lead feed solenoid valve

Claims (1)

(57) [Claims] A tap moving rod (15) is rotatably screwed into a first cylinder rod (13) provided in a fast-forward cylinder (5) so as to be able to move back and forth, and a tip of the tap moving rod (15). A tap (21) is provided at a portion, and a tip end portion of a gear rod (17) provided to be able to move back and forth and rotatable relative to the first cylinder rod (13) and a rear portion of the tap moving rod (15). The gear (41), which is screwed with the gear (25) provided at the rear end of the gear rod (17), is provided so as to be relatively movably engaged with the end of the spline joint (27). Second cylinder rod for reverse rotation (33)
And a first detector (LS1) for detecting the retreating end of the first cylinder rod (13) and a second detector (LS1) for detecting the reciprocating end of the first cylinder rod (13).
2) and a fourth detector (LS4) for detecting a forward end of a third detector (LS3) for detecting a retreating end of the second cylinder rod (33). If the fourth detector (LS4) is not turned on within a set time after the tapping is started by advancing the rapid feed cylinder (5), it is assumed that an overload has occurred and the fourth detector (LS4) ) Is turned on before the second detector (LS2) is turned on, it is assumed that there is no pilot hole for tapping, and the fourth detector is earlier than a predetermined time after the tapping is started. A machining error detection device characterized in that when (LS4) is turned on, the tap is broken and a tap machining error is detected.