DE102018006060A1 - Universally usable thread cutting, thread form and thread testing device with special working procedure for the semi and fully automatic production of threads and for the semi automatic and fully automatic testing of internal and external threads by means of appropriate tools - Google Patents

Abstract

With the invention, universally usable tapping, thread form and thread testing device with special working method for the semi and fully automatic production of threads and for the semi automatic and fully automatic testing of internal and external threads by means of test gauges with automatic recognition of the thread start as well as an integrated, automatic position adjustment, screw monitoring with automatic Screw-on position correction and tool holder, which can compensate for misalignment between the test gauge and the workpiece or thread, a device is available with which a special weight neutralization, exact thread length specification, as well as a gentle contact feed, can be used to produce or test threads permanently and reliably.

Description

Tapping tools or thread forming tools are usually used for thread production. In order to carry out the production as simply and relatively quickly as possible, there are various possibilities. The simplest production is to turn the tap manually into the borehole using a tool. It should be checked that the tap or tap is also screwed in at an angle to the drill hole. So that the alignment to the borehole is given automatically and the manufacturing time is shortened, the threading tools are clamped in a machine tool using a variety of tools such as tap holders, some of which are also available with manual torque adjustment. B. in a drill press or milling machine and the thread. However, this type of thread generation is not suitable for mass production and also not for installation in a manufacturing system. There is a wide variety of thread manufacturing devices for this.

Checks are essential to ensure the specifications (standards) of threads as well as the freedom of movement over the usable length. Most of these checks are carried out by sampling with good / bad gauges by hand. However, 100% control is increasingly required. In the case of mass production, 100% manual control no longer makes sense. Thread testers are then used for this task.

The most commonly used test concept of these thread testers is the automatic test of the threading with good gauges. The known test devices according to this test concept either have a rigid drive shaft test gauge connection or a test gauge holder, which enables the test gauge to have limited movement.

The rigid drive shaft-test gauge connection has the disadvantage that even the smallest misalignment from the test gauge to the workpiece produces incorrect test results. In the case of test devices with flexible test gauge mounting, the test gauge - with a horizontal test process - hangs downwards due to its own weight. When approaching the thread to be tested, the test gauge must first be aligned, i.e. the test gauge hanging down is brought into the horizontal position by pressing it onto the workpiece in connection with the rotary movement.

Even in the vertical test direction, in which the test gauge initially hangs down like a lace, the test gauge is thrown outwards by the rotational movement or centrifugal force to compensate for the compensation of the test gauge suspension and, in this case too, is only directed towards the thread to be tested. There is a risk that the test gauge and the thread to be tested will be damaged. This also significantly increases the wear on the test gauge.

The next risk of damage to the thread and test gauge as well as the wrong test results in the case of a vertical test is the known thread testers due to the weight of the test facility. A part of the kinetic energy is usually reduced by a spring, but because the approach to the test specimen in these test concepts is carried out by the dead weight, sufficient weight energy must be available to ensure that the test specimen is started.

There are also thread testers that work via a lead screw with a sprung test gauge suspension as axial compensation. However, this test concept is only suitable for the corresponding thread pitch and also has the screwing and alignment problems described.

With the invention "Universally usable thread cutting, thread forming and thread testing device with special working method for the semi and fully automatic production of threads and for the semi automatic and fully automatic testing of internal and external threads by means of appropriate tools" a device is available with which the thread can be easily and quickly and can be produced with integrated monitoring and control mechanisms, or is to be used for testing threads (as a thread testing device), which eliminates the described deficiencies of the known thread gauge testing devices.

Concept and functional description

The size of the workpieces, i.e. height or length, and thus also the start of the thread is automatically determined via an integrated start position detection. This contact position can be approached again for each work cycle and fixed for a specific product batch or a predetermined product quantity. Thanks to the automatic detection of the start of the thread and an integrated position transmitter, the device is able to precisely manufacture or test the specified thread lengths.

In addition, the tapping and testing device has a screw-on monitor and an automatic screw-on position correction.

For use as a test device

In order not to falsify the test results, an alignment error compensation is absolutely necessary when testing. On the other hand, the test gauge - even with rotation - should be exactly centered on the thread and not, as already described, cause the centrifugal force to spin around the sum of the alignment clearance.

For this reason, special holders have been developed for a wide variety of test gauges and test tasks that compensate for misalignments and, despite the axial and radial compensation options, have the rigidity to keep the test gauges centered on the thread to be tested, even during horizontal testing and during rotation.

There are two different versions for misalignment compensation.

For one version, a gauge holder with a rubber-metal connection is provided as compensation and in the second variant the necessary rigidity or central fixation is achieved by means of a spring force.

The necessary stiffness and compensation path can be adjusted via the rubber hardness (Shore) or via appropriate springs.

A contact feed adjustable in speed and pushing force moves the test gauge to the workpiece or to the beginning of the thread.

Via the rotary movement of the drive shaft or the tools (threading tool or test gauge) and the adaptable pressing force, they rotate themselves into the workpiece with the specified torque. If the working depth is not reached due to stiffness, the direction of rotation is switched over immediately and the tool is unscrewed using a return stroke torque. Arrived at the starting point (thread start), the device is brought into the basic position.

Individual working cycles can be realized via the device control in conjunction with the integrated feed mechanism. This has the advantage that the core hole can also be checked with a little extra time (when used as a test device).

Process safety is affected by the mass to be moved.

Especially when working vertically, the mass to be moved not only leads to incorrect test results, but can also damage the thread to be tested and the test gauge as well as the thread cutting or forming tool by striking the workpiece.

For this reason, an adjustable mass balance for neutralizing the weight mass and its acceleration energy has been integrated into the described invention. A special structure and the interaction of cylinders and their control units as well as smooth-running linear guides mean that the weight mass is largely neutralized via an adjustable force. The special design ensures that the weight neutralization remains relatively constant even during the manufacturing or testing process and thus over the entire working length.

The threading and testing device is moved from the suspended position to the workpiece via a linear feed, in which the feed speed and the pushing force can be adjusted. The specified screwing speed of the tools and the adjustable feed rate, which is only effective for contacting and screwing, cause the tools to be positioned relatively gently on the borehole. This prevents damage to the tools and when testing threads, damage to the thread. In addition, this prevents a test result that falsifies the friction pressure and prevents the flanks from being scratched (during the return) when producing threads. After the work process is finished, the thread unit is brought into the basic position.

The special working concept which means that the device can be used for the production of threads and for the testing of threads and the interaction of cylinders, force, measuring system, drive and control as well as the special tool holder are the essential features of the invention.

Claims (1)

Universally usable thread cutting, thread form and thread testing device with special working procedure for the semi and fully automatic production of threads and for the semi automatic and automatic testing of internal and external threads by means of test gauges with automatic recognition of the thread start as well as an integrated, automatic position adjustment, screw monitoring with automatic screw position correction and tool holder, which can compensate for misalignment between the test gauge and the workpiece or thread and, despite the effective centrifugal force, hold the test gauges or the thread tools centrally to the workpiece (borehole), characterized in that 1. That this device can be used to cut threads (using a cutting tool) or to shape them (using a thread forming tool) and can also be used as a thread testing device by using test gauges. 2. That the production of individual threads (semi-automatic) is possible or that individual thread tests can be carried out and that it is designed for fully automatic work. 3. that the contact feed is adjustable, i.e. the corresponding tools can be pressed onto the workpiece (borehole) by hand (in the case of semi-automatic) or fully automatically via a linear feed with adjustable feed speed and pushing force, and screw-on monitoring with automatic screw-on position correction is provided. 4. that for vertical work the mass to be moved is neutralized relatively uniformly over the entire working length, so that work can be carried out without negative (falsifying) flank pressure and the device is therefore also suitable for re-tapping threads. 5. that automatic recognition of the start of the borehole with independent position adjustment is integrated into the thread production and testing device through the interaction of cylinders, position fixation, two linear slides, throttles and pressure regulating valves and a position sensor. 6. that through and blind holes are feasible and testable. 7. that the required torques for the different thread sizes can be called up and monitored accordingly, thus ensuring tool breakage and tool sharpness monitoring. 8. that a special tool holder has an alignment error and axial compensation part which holds the tool centrally to the borehole. 9. That there is an automatic position adjustment for workpieces of different heights or lengths. 10. that an interface is provided for a connection to a higher-level controller and thus the device is also ideally suited for integration into a production system.