DE71848C - Method and device for the production of locking screws - Google Patents

Description

IMPERIAL

PATENT OFFICE

If you change the relative screw movement of the workpiece when cutting screws against the tool in such a way that one movement (e.g. the straight line) becomes a periodic one, while the other (rotary motion) remains uniform, one obtains screws with a periodic one Thread pitch (locking screws). Depending on the nature of the periodic movement, the one touched on in a period increases Thread part different pitch, the same can be, for. B. broken at an acute or obtuse angle or also be curved in a wave shape, among others. m.

The following procedures are used to manufacture the locking screws:

1. Transform the uniform linear movement of the workpiece (tool) into a rectilinear periodic movement and leave the tool (workpiece) uniform rotate.

2. Convert the uniform rotary motion of the tool (workpiece) into a periodic rotary motion and let the uniform rectilinear motion of the workpiece (Tool unchanged.

3. One transforms both the uniform rectilinear movement of the work piece (tool) as well as the uniform rotary movement of the tool (workpiece) in the same way periodic movements.

The periodic motion can also be converted into a uniform motion and into Decompose vibrations. Ever. after distributing the mentioned movements to the tool and work piece result in different arrangements for ratchet screw cutting machines. A machine on which the tool (workpiece) rotates uniformly is used to illustrate the process, the workpiece (tool) moves uniformly in the horizontal direction and that rotating tool (work piece) is also set in horizontal vibrations.

The attached drawing shows:

Fig. Ι and 2 respectively the front. Top view of the machine,

3 and 4 the upper and respectively. Side view of the swing device,

Fig. 5 shows the end view of the necessary for cutting the thread for the cutting tools Copier disk,

Fig. 6 shows a partially developed cylindrical section through the thread a shaft locking screw and the associated cutting tool,

7 and 9 screws with ordinary and ratchet screw threads, which latter the cutting tools are to be taken as a basis, and

8 shows a screw with an ordinary and shaft thread.

The middle open and crossed belts between the transmission and the overhead transmission for pre- and Backward movement set up machine is a lead screw lathe and -Screw cutting machine with copier device effective in the direction of the working spindle.

The lead screw d , which is stored in the bed and driven by the work spindle by the wheels abc, fig.

clip can be attached, a straight horizontal movement. Furthermore, a shaft g is driven by the gear pair hi from the work spindle; A conical copier disk k is firmly keyed onto this shaft. The guideline of the conical shell is composed of a number of identical waves or arcs, which are folded over into the plane in FIGS. 4 and 5 and shown by dashed lines.

As can also be seen in FIGS. 3 and 4, a two-part ring is inserted into the annular groove of a two-jaw chuck / which is loosely attached to the work spindle by means of wedge and groove and serves to hold the cutting drill or screw bolt; two screws mn, on the conical part of which the eyes op the rocker arm fork, are firmly screwed into them. A second fork q attached to a lateral extension of the right bearing arm engages over the rocker arm fork, in the eyes of which the rocker arm is supported by the screws rs. At the upper end of the rocker arm, a conical roller t is arranged on the side, which is pressed firmly against the conical surface of the copier disk by a spiral spring u , so that when the copier disk rotates, the rocker arm and the rotating two-jaw chuck are set in horizontal oscillations. The deflection of the rocker arm can be changed depending on the wave height of the shaft thread to be cut by adjusting the fork q . The swing device can be z. B. turn off by attaching a two-part ring between the copir disc and the rocker arm.

Shaft locking screws can be used on the machine without using new cutting tools you proceed just like when cutting screws on an ordinary one Lathe. So that the tip on the tailstock does not prevent the vibrations of the clamped object, the same is either to bed resiliently, or you give it the shape shown in Fig. 1 and 2 and makes the grain hole cylindrical.

When using the machine as a Copir screw cutting machine, new cutting tools are required which do not prevent the vibrations to be imparted to the workpiece or tool itself. As a result, material has to be removed from both thread surfaces of the cutting tools in order to gain space for the cut wave crests when cutting; this removal of material can now have taken place in such a way that during cutting the thread surfaces of the cutting tools and the cut thread always touch in surface elements. In the case of a very flat shaft thread (see Fig. 6), the contact surfaces between the tool and the workpiece are large enough to force the tool to perform the desired shaft movement after it has been inserted into the workpiece for the first time (after cutting). Cutting tools, which should have this property of positive running, are to be provided with the thread shown in Fig. 9, which can also be cut on the machine described, only then the copier disk shown in Fig. 5 is to be attached to the shaft g .

The way the machine works when the cutting tools are made is exactly the same that of an ordinary lead screw and copier lathe. The cutting tools are initially provided with an ordinary thread, whereupon on the latter, namely on both Threaded surfaces, the arcuate recesses are cut. That shown in FIG The thread can also be used in the same way as the arcuate indentations so that the tool (workpiece) has periodic movements perpendicular to the Work spindle axis granted. When milling the grooves in the cutter or when making them of the cutting jaws, care must be taken that the cutting edges are precisely aligned with the division of the arcuate indentations coincide.

The way the machine works as a Copir screw cutting machine is as follows:

Through the lead screw d , the nut or the cutting stock receives a uniform horizontal movement, while the cutting drill or screw bolt fastened in the two-jaw chuck rotates uniformly and is also set in oscillation by the oscillating device in the direction of the working spindle axis; however, this makes the pitch of the thread to be cut a periodic, undulating one. However, since, as already mentioned above, the cutting tools automatically pass through the work piece after cutting, the shaft locking screw can also be produced on any conventional screw cutting machine, provided that the cutting is initiated by a swing device suitably arranged on the machine .

The process for making the sharp-toothed ratchet screws consists in dafs initially normal thread when the machine is moving forward and when the machine is in reverse the teeth are cut.

Die-assemblies for a screw cutting machine for the production of the ratchet screw can be made similar to those shown. After switching the machine to reverse gear, work

and lead screw periodically set in rotation by a switching mechanism, while the copier disc continuously rotates.

The cutting tools for cutting the teeth are also with sharp-toothed threads provided and is used when milling the grooves in the cutter or when making the Dies. care must be taken that the cutting edges correspond exactly to the division of the Ratchet teeth collapse.

Claims (1)

Patent Claims: i. Process for the production of locking screws of the type protected by patent no. 53163, characterized in that a periodic thread pitch is achieved in that the workpiece is also guided in periodic motion against suitable cutting tools in one screw motion.
A device serving to carry out the above-mentioned method, characterized in that the work piece (tool) is made to vibrate by means of a suitably arranged lever from a rotating copier disk. A cutting tool for carrying out the process referred to under 1., thereby marked that the same is provided with cut ratchet screw thread and that grooves are milled into this thread in such a way that the cutting edges are always in a ratchet tooth start fall. 1 sheet of drawings.