WO2011044970A1

WO2011044970A1 - Device for rolling threads

Info

Publication number: WO2011044970A1
Application number: PCT/EP2010/005398
Authority: WO
Inventors: Bernd-Arno Behrens; Hagen Schmidt; Philipp Silberkuhl; Dietmar Schnier
Original assignee: Gottfried Wilhelm Leibniz Universität Hannover
Priority date: 2009-10-15
Filing date: 2010-09-02
Publication date: 2011-04-21
Also published as: CN102574195A; JP2013507256A; RU2012119780A; EP2488314A1; DE102009049580A1; IL219141A0; US20120186318A1

Abstract

The invention relates to a device for introducing a thread into a workpiece having a cylindrical outer surface by means of thread rolling, comprising a profiling tool (7) having a profile without pitch, wherein the axis of the profiling tool is at an angle or parallel to the axis of the workpiece, wherein the profiling tool (7) is formed by a circular disk (9) rotatably mounted about the axis (8) of the disk, on the outer edge of which disk two annular, coaxial profiles (10) without pitch protrude, wherein said profiles form an annular space therebetween that corresponds in shape and dimensions to the thread profile of the thread to be created.

Description

Device for thread rolling

The invention relates to a device for introducing a thread into a workpiece with a cylindrical outer surface by thread rolling with a

Profiling tool with stepless profile, the axis of the

Profilierungswerkzeuges is particularly oblique to the axis of the workpiece.

Thread rolling, often also referred to as thread rolling, is generally understood to mean the non-cutting production of thread by cold forming, in which the profile is rolled into the surface of the corresponding pipe part. According to DIN 8580, thread rolling is part of forming, more accurate pressure forming and rolling. The transformation is based on the generation of

Compressive stresses due to one or more tools that are imaged on the workpiece. This procedure is much faster and larger

Quantities cheaper than other methods of manufacturing

Threading, namely threading.

So the advantages of thread rolling are:

- no grain boundary interruption, - what happens when cutting;

- The cold deformation surface hardening is achieved;

- Pressed thread flanks can be produced;

- A higher wear resistance occurs;

- Reduced notch sensitivity

- No chips, thus lower material requirements

- Less effort than when tapping In conventional thread rolling with flat tools has the

Jaw pair the thread counter-profile with the pitch angle of the thread, one jaw fixed and the other is arranged to be movable. The workpiece is unrolled under the influence of frictional forces, so that the whole

The extent of the thread is created. The dies have a tapered inlet and outlet and a straight calibration part.

Thread rolling with round tools can be done in grooving or

Passing procedure done. Short or long threads can also be rolled to the waistband. When piercing the rollers have the corresponding thread profile with the same pitch angle, but

opposite twist direction. The workpiece is either held with a ruler (centerless) or stretched between points. Apart from slight compensatory movements, the workpiece remains axially steady during the rolling process. Since the ratio of roller to workpiece diameter and the number of gears must be exactly matched, a pair of rollers can only be used for a specific thread.

In the continuous process, the rolls have juxtaposed,

stepless thread profiles. They will be around the required

Slope angle pivoted about its horizontal longitudinal axis. As a result, the axial feed of the workpiece is generated by the amount of increase in one revolution. The rollers can also be used to a limited extent for different workpiece diameters. In this method, however, results in a lower pitch accuracy compared to the piercing method.

Self-opening thread rolling heads usually have three rollers. They are brought axially to the workpiece and pull by the inclination of the rollers automatically on the workpiece. If the intended thread length is reached, the roller head opens automatically and can be withdrawn.

The known threaded rolling devices are always stationary, since they have considerable external dimensions and a large weight. An electric drive is always required. Also, the state of the art in the field of Thread owning the fact that it is performed with rollers as well as by machine. In the course of an intended change in the thread would inevitably several tools, preferably roles are replaced, and a machine drive can be provided.

The object of the invention is a maximum transportable, comparatively easy to use manually operable device for rolling

To create external threads, with simple construction and low

External dimensions.

This object is achieved in that the

Profiling tool is formed by a circular, rotatably mounted about its axis disc, projecting on the outer edge of two annular, coaxial, stepless profiles which form an annular space between them, which corresponds in shape and dimensions to the thread profile of the thread to be created.

The invention relates to a device for thread rolling, in which between the rolling tool and jig a workpiece is to be clamped and clamped by means of screw feed. After locking can now be rolled by a rotary motion by hand, a thread in the workpiece. The thread geometry of the workpiece is determined by the

Rolling tool defined. The rolling tool is preferably as a

Quick-change plug-in system executed and can thereby customize any external thread.

Such a device has a simple construction on such a small design that it can be carried and operated by hand. It does not require an electric drive, but the forces can through

Muscle force are generated. The workpieces will not be used

Thread rolling device, but the device can be easily carried to the point at which a thread is to be created. In addition, from the prior art not known, the workpiece as

Bear plain bearings, because this could damage the expertise of the average expert according to a freshly rolled thread. Rather, a professional will deliberately try such

Sliding bearing to avoid damage to the thread.

In the solution according to the invention, the solidification of the material by the rolling process is used. Thus, by a combination of the machining process in the form of thread rolling, with a

Dimensioning and material selection of the delivery device allows the production of a standardized thread on a workpiece. In this case, cut threads would be comparatively more affected by axial "plain bearing delivery"

Material-related to minimize the burden on the workpiece.

Also, the use of inaccessible workpieces (within a complicated only to be dismantled machine) is made possible by the present invention.

A secure hold with the simplest production is given when the cylindrical workpiece is held in a part-cylindrical groove of a bearing part, whose longitudinal axis is arranged obliquely to the axis of the profiling tool. In this case, the bearing part can be adjustable transversely and in particular at right angles to the axis of the profiling tool, in particular by hand.

An advantageous alternative mounting of the workpiece is achieved when the inner wall of the part-cylindrical groove has a thread cutout, which in terms of shape and pitch substantially to create the workpiece

Thread corresponds.

Furthermore, it is proposed that the cylindrical workpiece is mounted on the opposite side of the profiling tool by at least two axially parallel to the workpiece rollers, which are mounted on a support member. A simple and easy handling is given by the fact that

Adjusting the distance between the profiling tool and the bearing part, the bearing part is actuated by a threaded rod, in particular by hand.

Preferably, it is proposed that the workpiece in the space between the profiling tool and bearing member axially and / or radially be introduced and removed. It is particularly advantageous that the

Thread rolling device manually operated as a hand tool and

is transportable.

Embodiments of the invention are shown in perspective in the drawings and will be described in more detail below. Show it

Figure 1 shows a first embodiment in which the workpiece in the groove of a

Storage part is held against the profiling tool,

Figure 2 shows a second embodiment in which the workpiece by two

Rolls are held against the profiling tool,

Figure 3 shows an embodiment with a closed annular

Support block.

The thread rolling device 1 has a U-shaped support block 2, with a base 3 from which two legs 4, 5 go out. The first leg 4 is divided by a longitudinal slot 6 in two leg halves 4a, 4b and in the slot 6 a profiling tool 7 is mounted on an axis 8, the ends of both leg halves 4a, 4b penetrate to thereby be held by the leg 4.

The profiling tool has a circular disc 9, on whose outer circular edge two adjacent annular coaxial profiles 10 of the same diameter and the same cross-section project such that they form a coaxial groove-shaped annular space 11 between them whose cross-section in shape and dimensions of the cross section of the thread profile of corresponds to the thread to be generated. Here, the dimensions and the cross section of the profiles 10 are selected so that they correspond to the dimensions and the cross section of the thread of the thread to be created.

To the rod-shaped workpiece with a cylindrical outer side against the

Press profiling tool, a bearing member 20 is provided which has a part-cylindrical groove 12 in which the workpiece rests, wherein the concave groove surface can be profiled according to the thread to be produced. On the rear side of the bearing part 20 to the groove 12 a threaded rod 12 is mounted on this, which rests in a corresponding threaded bore of the second leg 5 and is rotatable about a handle 14 at its outer end by hand about its longitudinal axis to the support member 20 move the profiling tool to and fro.

Instead of a storage of the profiling tool 7 in the first leg, the profiling tool 7 may be mounted in the storage part 20 and the first

Leg 4 form the anvil with groove 12. Furthermore, the bearing part 20 may carry two guide wheels or two guide rollers 21, which run with profilings in the thread of the workpiece, as shown in FIG. 2. Alternatively, the surfaces of the rollers 21 may be smooth cylindrical, especially in one

Repair of a thread.

Furthermore, the support block 2 may not be U-shaped, but closed, d. H. the two legs 4, 5 are suppressed by an upper part 2a so that the

Support block 2 is annular and the storage part 20 is in its central opening, as shown in FIG. 3 shows.

In all embodiments, the axis of rotation 8 of the disc 9 and thus also the two profiles 10 are arranged obliquely relative to the axis of the groove 12 and against the guide edges 21, so that a thread with a

continuing threading is formed in the workpiece and not just annular grooves. The angle of this oblique arrangement is about 0.4 to 10 degrees. To repair damaged thread may be missing an inclination, ie that then the guide in particular the groove 12 in the storage or

Guide member 20 is parallel to the axis 8 of the profiling tool.

The advantage of using the tool according to the invention without

Machine is that it can be carried out locally, can be used flexibly, and, for example, set-up times eliminated. The tool is thus suitable for the production of small quantities and is also clear

cheaper to produce than e.g. a rolling head, because it consists of a few, simple parts.

This is made possible by the fact that exactly one single profile roller is used for the shaping, which is arranged opposite a bearing element. The profile rollers in known tools either have a profile

Slope or a profile without slope in the form of circular circumferential ribs or rings. In the present invention, a non-lead profile is also used for shaping, but this profile is characterized in that it has exactly two circumferential ribs or rings, which form between them an annular gap which corresponds approximately to the thread profile to be formed. Although it could have several rings, but only two are in an application engaged on the workpiece.

This shape of the profile roller (exactly two circumferential rings or ribs in engagement with the defined gap) ensures that the force that must be applied in order to allow the profile roller to penetrate into the material is minimized. Furthermore, an inclination of this profile roller relative to the workpiece axis to about the thread pitch that can be dispensed with a complicated forced operation as in known tools, and the profile role yet a profile with exactly the desired slope in the

Rolling in the workpiece.

In order to apply the force necessary for introducing the profile roller into the workpiece, the workpiece is supported on the opposite side of the profile roller with a bearing element. This can, for example, as a solid with be formed adapted to the thread negative profile. It is relevant to the bearing element that it transmits the force as large as possible and not only selectively to the workpiece.

An expedient embodiment of the tool is similar to one

Pipe cutter, which differs from the invention described so far in that instead of a profile-giving, inclined profile roller, a straight cutting wheel is used.

The proposed embodiment of the tool is characterized in that it is designed as a mobile mitführbares hand tool. That's it

Profilierungswerkzeug and the bearing element relative to each other tangentially deliverable. At least one rest position is adjustable, in which a

Workpiece between Profilierungswerkzeug and storage element is insertable. The possibility of both an axial and a tangential

Insertion option for the workpiece offers maximum flexibility.

In addition, with the tool thread not only at the end of a

Workpiece, but can be formed at any point. It is crucial that the profiling tool and the bearing element are in a power flow plane, so that no bending or tilting moments on the workpiece to be machined arise by a locking operation. The tool is designed so that the profiling tool relative to

Workpiece axis is inclined at an angle which corresponds approximately to the thread pitch.

Furthermore, by the possible delivery of a preparation of the tool not only at the end of the workpiece is possible, but the thread can from the

Workpiece center are rolled starting from the end of the workpiece.

As a result, the tool can not be accidentally set at an angle. Also, a touch of the workpiece at the workpiece end, as in the

Thread cutting is common, to avoid tilting or oblique attachment, can be omitted. At the same time, the advantageous properties of chipless machining can be used by means of the device according to the invention, so that the advantages of a thread produced by such a method can be realized manually by hand.

In a surprisingly simple manner, the external thread is without cutting after delivery with a predetermined feed force in the working position by turning the entire device around the tool longitudinal axis

introduced, wherein the thread geometry to be created by the

Profiling tool with respect to the profile depth and profile shape is clearly predefined. Tilting or imprecise insertion of the profile is virtually impossible. Also, overfeeding is not possible because the forces increase exponentially as soon as the space between the two profiled ribs or rings is completely filled by the formed workpiece, the geometry of the workpiece only requiring a substantially cylindrical outer surface, and Furthermore, the external thread can be completely formed to a defined point so that a thread can be produced without an outlet.

Of course, other embodiments of the tool are conceivable in which the workpiece can be inserted only axially, but this can be done little strong, since the forces can be taken cheaper by the body of the tool.

Another possible use of the tool is the thread repair. With the tool deformed external thread can be formed back again.

Due to the inclination of the profile roller, larger damage can thus better repair better than with the known tools. But, as stated above, repairs of threads can be made in high quality even if the profile rolls are not skewed, i. H. that its axis is parallel to the longitudinal axis of the workpiece.

Because the profile of the profiling tool and the angle at which the

Profiling tool is inclined relative to the workpiece axis, from which to are dependent on the generating thread type, it is expedient to use parts of the

Tool (die-casting roller and counter-holder) effortlessly

interchangeable design, so that the tool can be used for the production of different types of threads. This is also useful because the backstop and the profile roller wear out over time and then have to be renewed.

Claims

claims

1. Device (1) for introducing a thread into a workpiece with

cylindrical outer surface by thread rolling with a

Profilierungswerkzeug (7) with stepless profile, wherein the axis of the profiling tool is inclined or parallel to the axis of the workpiece, characterized in that the profiling tool (7) by a circular, about its axis (8) rotatably mounted disc (9) is formed, at the outer edge of two annular coaxial, stepless profiles (10) protrude between them form an annular space (10) which corresponds in shape and dimensions to the thread profile of the thread to be created.

2. Apparatus according to claim 1, characterized in that the cylindrical workpiece in a part-cylindrical groove (12) of a

Bearing part (20) is held, whose longitudinal axis is arranged obliquely to the axis of the profiling tool (7).

3. A device according to claim 2, characterized in that the bearing part (20) is adjustable transversely and in particular at right angles to the axis of the profiling tool (7) in particular by hand.

4. Apparatus according to claim 2 or 3, characterized in that the inner wall of the part-cylindrical groove (12) has a threaded recess which corresponds in shape and pitch substantially to the workpiece to be created thread.

5. The device according to claim 1, characterized in that the cylindrical workpiece on the profiling tool (7) opposite side by at least two axially parallel to the workpiece rollers (28) is mounted, which are mounted on a support member (20).

6. Device according to one of claims 2 to 5, d a d u r c h

in that for adjusting the distance between the profiling tool (7) and the bearing part (20) the bearing part (20) can be actuated by a threaded rod (13), in particular by hand.

7. Device according to one of the preceding claims, characterized

in that the workpiece can be inserted and removed axially and / or radially into the space between the profiling tool (7) and the bearing part (20).

8. Device according to one of the preceding claims, characterized

characterized in that it is manually operable and transportable as a hand tool.