DE102014106328B4 - Method for producing a holder for a tool and/or a workpiece and corresponding holder - Google Patents

Abstract

Method for producing a holder (1) for a tool and/or a workpiece, with a collet holder (2) and an external thread (3) as well as a collet (4) and a union nut (5) which has a contact surface (6) and an internal thread (7), wherein the contact surface (6) is operatively connected to the collet (4) and the internal thread (7) is operatively connected to the external thread (3), characterized by the following steps: - clamping/holding the union nut (5) on two sides which are opposite one another in relation to a central/rotational axis (L), - pressing the union nut (5) oval by applying force to the clamping/holding points, - inserting the internal thread (7) into the union nut (5), - releasing the clamping of the union nut (5), - rotating the union nut (5) about the central/rotational axis (L), - clamping/holding the union nut (5) again on two sides which are opposite one another in relation to a central/rotational axis (L), Opposite sides with respect to the central/rotation axis (L),- pressing the union nut (5) into an oval again by applying force to the clamping/holding points,- inserting the contact surface (6) in the form of a cone into the union nut (5),- loosening the clamping of the union nut (5),- screwing the union nut (5) with the internal thread (7) onto the external thread (3),- establishing the operative connection between the contact surface (6) of the union nut (5) and a conical contact surface of the collet (4).

Description

Technical area

The invention relates to a method for producing a holder for a tool and/or a workpiece according to the preamble of claim 1 and a corresponding holder for a tool and/or a workpiece according to the preamble of claim 2.

State of the art

Various systems for holding tools and/or workpieces are known from the state of the art. In particular, rotating tools and/or rotating workpieces are usually used for this purpose in machines for machining workpieces. Such workpieces and/or tools in particular should have the highest possible concentricity during the machining process.

Typical holders for tools and/or workpieces are made up of several parts and, in addition to the holder, have a collet and a union nut that are operatively connected to the holder. The tool and/or the workpiece are clamped in the collet, with the collet being fixed in the holder by the union nut.

Although these holders already have a certain degree of concentricity, the manufacture of holders with a very high degree of concentricity is very expensive due to the very high precision required during manufacture today. Furthermore, even with high-precision manufacture of the holder, a slight slant of the tool and/or the workpiece cannot be prevented. This occurs because the union nut is always slightly slanted when tightened due to the thread pitch, which means that the collet is also drawn into the holder at an angle.

In order to achieve a certain specified concentricity, such holders are often standardized components. This means that at least a minimum standard can be created in the area of the relevant properties, such as concentricity in particular.

Just as an example, reference is made to the German standard DIN 69871 Part 1, in which the so-called steep tapers are standardized. The steep taper is the standardized form of a tool cone for clamping tools in the main spindle of a machine tool.

From the US 2003 / 0 184 028 A1 A collet is known that can be used and reused without readjustment or realignment. It uses frustoconical and tangential mating surfaces, elliptical mating elements, alignment means for dowels and keyways, tension and tension/travel limiting means to prevent binding and excessive expansion or contraction of collet head elements. This enables an accurate fit and safe adjustment of collets and their mating and interacting parts.

The EN 10 2009 044 049 A1 relates to a collet chuck with a chuck body that is or can be connected in a rotationally fixed manner to a drive spindle, with a collet and a conical sleeve associated with the chuck body. The conical sleeve is arranged axially immovably on the chuck body. A threaded connection is effective between the chuck body and the collet.

From the DE 38 24 462 C2 In turn, an adjustment device is known, in particular for tools such as drills, milling cutters, taps or milling cutters, reamers or similar rotary tools, with a first element having an associated longitudinal axis and a second element having an associated longitudinal axis and with parts connecting the two elements to one another, by means of which the two elements can be offset relative to one another while maintaining the angle between the axes.

Object of the invention

The object of the invention is to provide a manufacturing method for a tool holder and a corresponding holder with improved concentricity. Furthermore, the object of the invention is to minimize an inclination of a clamping element of the tool holder.

Solution to the task

The features of claims 1 and 2 lead to the solution of the problem.

In a typical embodiment, a holder for a tool and/or a workpiece has a collet holder and an external thread as well as a collet and a union nut. The union nut has a contact surface and an internal thread. The contact surface of the union nut is in operative connection with the collet and the internal thread of the union nut is in operative connection with the external thread.

The union nut also has a central/rotational axis. The central/rotational axis typically describes an imaginary straight line around which the union nut rotates when the collet holder is tightened or loosened. The central axis also describes a straight line around which the union nut is at least partially rotationally symmetrical. For the sake of simplicity, the central/rotational axis will be referred to as the central axis in the following.

• - Einspannen/Festhalten der Überwurfmutter auf zwei sich in Bezug auf die Mittelachse gegenüberliegenden Seiten,
• - Oval drücken der Überwurfmutter durch Krafteinwirkung an den Einspann-/Festhaltestellen,
• - Einbringen des Innengewindes in die Überwurfmutter,
• - Lösen der Einspannung der Überwurfmutter,
• - Drehen der Mutter um die Mittelachse, wobei die Drehung bevorzugt im Bereich von 90° liegt,
• - Erneutes Einspannen/Festhalten der Überwurfmutter auf zwei sich in Bezug auf die Mittelachse gegenüberliegenden Seiten,
• - erneutes Oval drücken der Überwurfmutter durch Krafteinwirkung an den Einspann-/Festhaltestellen,
• - Einbringen der Kontaktfläche in Form eines Konus in die Überwurfmutter,
• - Lösen der Einspannung der Überwurfmutter,
• - Aufschrauben der Überwurfmutter mit dem Innengewinde auf das Außengewinde,
• - Herstellen der Wirkverbindung der Kontaktfläche der Überwurfmutter mit einer konischen Kontaktfläche der Spannzange.

The method according to the invention for producing the holder for a tool and/or a workpiece relates to the union nut and comprises the following steps:

• - Clamping/holding the union nut on two opposite sides with respect to the central axis,
• - Oval pressing of the union nut by applying force at the clamping/holding points,
• - Inserting the internal thread into the union nut,
• - Loosen the clamping of the union nut,
• - Rotating the nut around the central axis, with the rotation preferably being in the range of 90°,
• - Re-clamping/holding the union nut on two opposite sides with respect to the central axis,
• - re-press the union nut into an oval shape by applying force to the clamping/holding points,
• - Inserting the contact surface in the form of a cone into the union nut,
• - Loosen the clamping of the union nut,
• - Screw the union nut with the internal thread onto the external thread,
• - Establishing the operative connection between the contact surface of the union nut and a conical contact surface of the collet.

Due to the method according to the invention for producing the holder, the contact surface of the union nut, which is a cone, is at least partially elliptical. The internal thread of the union nut is also at least partially elliptical due to the method according to the invention for producing. In a typical embodiment, the ellipses of the contact surface and the internal thread are arranged at an angle to one another around the central axis of the union nut, preferably the angle is about 90°, although deviations from this are also possible.

The expression that the ellipses are arranged at an angle to one another is intended to express that the main axes of the respective ellipse are rotated relative to one another. The main axis describes the axis/straight line on which both the two focal points of the ellipse and the center of the ellipse lie. In one embodiment, the main axes of the ellipses are rotated by approximately 90° relative to one another. Other embodiments in which the main axes are rotated at a different angle to one another are also intended to be covered by the present invention.

The contact surface of the union nut is at least partially designed as an elliptical cone. The term elliptical cone describes that a surface that is spanned perpendicular to the central axis of the union nut and is limited at its edges by the contact surface of the union nut has the shape of an ellipse.

In one embodiment, the two focal points of the ellipse are only a short distance from the center of the ellipse. In a typical embodiment, the center of the ellipse corresponds to the point on the ellipse through which the center axis of the union nut passes perpendicular to the surface of the ellipse. In a typical embodiment, the same applies to the properties of the at least partially elliptical internal thread.

The collet holder of the holder has an inner cone that is suitable for receiving the collet. In one embodiment, the collet is a sleeve and preferably has the shape of a double cone, wherein a first cone of the double cone is provided to come into operative connection with the inner cone and a second cone is provided to come into operative connection with the contact surface of the union nut.

Furthermore, the collet is radially slotted, which makes it possible to press the collet together and fix a tool and/or workpiece in a holder. The holder of the collet is typically round, but can also be designed as a recess with a polygonal cross-section.

The union nut according to the invention has a contact surface which is at least partially designed as an elliptical cone. Furthermore, the union nut according to the invention has an internal thread which is at least partially elliptical.

The workpiece and/or tool is inserted into the holder in the collet chuck before it is clamped by tightening the union nut. When the union nut is tightened, the collet is pressed into the inner cone of the collet holder. Due to the inventive manufacturing process of the holder, there are two opposing support areas between the collet and the union nut and between the union nut and the collet holder, whereby the support areas between the union nut and collet and the support areas between the union nut and the collet holder are arranged at an angle to one another around the central axis of the union nut. In one embodiment, the angle is approximately 90° in each case.

This design means that the collet is mounted in a wobbling manner between the collet holder and the union nut when tightening. This prevents the slight inclination of the union nut, which cannot be avoided due to the thread pitch, from being transferred to the collet. This in turn means that the collet is pressed cleanly centered into the inner cone of the collet holder, which can significantly increase the concentricity of the tool and/or the workpiece that is clamped in the holder.

Character description

• 1 eine Explosionsdarstellung eines erfindungsgemässen Halters für ein Werkstück und/oder Werkzeug;
• 2 Draufsicht auf eine Überwurfmutter des Halters nach 1; und in
• 3 eine schematische Schnittdarstellung durch die Überwurfmutter nach 2.

Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments and from the drawings, which show in

• 1 an exploded view of a holder according to the invention for a workpiece and/or tool;
• 2 Top view of a union nut of the holder after 1 ; and in
• 3 a schematic sectional view through the union nut according to 2 .

Example

1 shows an exploded view of a holder 1 for a tool and/or a workpiece, which has a collet holder 2 and an external thread 3 as well as a collet 4 and a union nut 5 and corresponds to the design of a steep taper.

The union nut 5, shown in 2 , has a contact surface 6 in addition to an internal thread 7. In a typical embodiment, the contact surface 6 of the union nut 5 is in operative connection with the collet 4 and the internal thread 7 of the union nut 5 with the external thread 3 of the collet holder 2.

Furthermore, in one embodiment, the collet 4 is designed as a double cone, wherein a first cone 10 of the collet 4 is in operative connection with an inner cone 8 of the collet holder 2.

Preferably, the first cone 10 and the inner cone 8 are complementary in their shape to each other.

In a typical embodiment, the contact surface 6 of the union nut 5 is designed as a cone that is at least partially elliptical. Furthermore, the contact surface 6 is designed to be at least partially complementary to a second cone 11 of the collet 4. The internal thread 7 of the union nut 5 is also at least partially elliptical in a typical embodiment. The ellipses of the contact surface 6 and the internal thread 7 are arranged at an angle to one another around a central/rotational axis L of the union nut 5. In one embodiment, this angle is approximately 90°.

Furthermore, the collet 4 is radially slotted in a typical embodiment. The collet 4 also has a holder 9 that is suitable for holding a tool and workpiece. The radial slots allow a diameter of the holder 9 of the collet 4 to be reduced when the union nut 5 is tightened, whereby the tool and/or the workpiece is clamped firmly in the holder 9. The diameter of the holder 9 is reduced by the collet 4 being pressed into the inner cone 8 of the collet holder 2.

Because the contact surface 6 of the union nut 5 is a cone that is at least partially elliptical and because the internal thread 7 is also elliptical, the collet 4 is mounted in a wobbling manner between the union nut 5 and the collet holder 2 when the union nut 5 is tightened onto the collet holder 2. This is the case because the inventive manufacturing method of the holder creates four contact areas that are preferably offset from one another by approximately 90°.

In 3 a schematic sectional view of the union nut 5 is also shown. In this, the elliptical cross section of the contact surface 6 and the elliptical cross section of the internal thread 7 are shown. It should be noted that, in order to better illustrate the inventive design of the union nut 5, the focal points of the ellipses shown are further apart. different than is typically the case in reality.

• - Einspannen/Festhalten der Überwurfmutter 5 auf zwei sich in Bezug auf die Mittel-/Rotationsachse L gegenüberliegenden Seiten,
• - Oval drücken der Überwurfmutter 5 durch Krafteinwirkung an den Einspann-/Festhaltestellen,
• - Einbringen des Innengewindes 7 in die Überwurfmutter 5,
• - Lösen der Einspannung der Überwurfmutter 5,
• - Drehen der Überwurfmutter 5 um die Mittel-/Rotationsachse L
• - Erneutes Einspannen/Festhalten der Überwurfmutter 5 auf zwei sich in Bezug auf die Mittel-Rotationsachse L gegenüberliegende Seiten,
• - erneutes Oval drücken der Überwurfmutter 5 durch Krafteinwirkung an den Einspann-/Festhaltestellen,
• - Einbringen der Kontaktfläche 6 in Form eines Konus in die Überwurfmutter 5,
• - Lösen der Einspannung der Überwurfmutter 5,
• - Aufschrauben der Überwurfmutter 5 mit dem Innengewinde 7 auf das Außengewinde 3,
• - Herstellen der Wirkverbindung der Kontaktfläche 6 der Überwurfmutter 5 mit einer konischen Kontaktfläche der Spannzange 4.

The method for producing a holder 1 with the above-mentioned properties comprises, in a typical embodiment, the following steps:

• - clamping/holding the union nut 5 on two opposite sides with respect to the central/rotational axis L,
• - Oval pressing of the union nut 5 by applying force at the clamping/holding points,
• - Inserting the internal thread 7 into the union nut 5,
• - Loosen the clamping of the union nut 5,
• - Turning the union nut 5 around the center/rotation axis L
• - Re-clamping/holding the union nut 5 on two opposite sides with respect to the central rotation axis L,
• - press the union nut 5 into an oval shape again by applying force to the clamping/holding points,
• - Inserting the contact surface 6 in the form of a cone into the union nut 5,
• - Loosen the clamping of the union nut 5,
• - Screw the union nut 5 with the internal thread 7 onto the external thread 3,
• - Establishing the operative connection between the contact surface 6 of the union nut 5 and a conical contact surface of the collet 4.

List of reference symbols

1

holder

2

Collet holder

3

External thread

4

Collet

5

Union nut

6

Contact surface

7

inner thread

8th

Inner cone

9

Recording

10

first cone

11

second cone

L

Center/rotation axis

Claims (6)

Method for producing a holder (1) for a tool and/or a workpiece, with a collet holder (2) and an external thread (3) as well as a collet (4) and a union nut (5) which has a contact surface (6) and an internal thread (7), wherein the contact surface (6) is operatively connected to the collet (4) and the internal thread (7) is operatively connected to the external thread (3), characterized by the following steps: - clamping/holding the union nut (5) on two sides which are opposite one another in relation to a central/rotational axis (L), - pressing the union nut (5) oval by applying force to the clamping/holding points, - introducing the internal thread (7) into the union nut (5), - releasing the clamping of the union nut (5), - rotating the union nut (5) about the central/rotational axis (L), - clamping/holding the union nut (5) again on two sides which are opposite one another in relation to the central/rotation axis (L) opposite sides, - pressing the union nut (5) into an oval again by applying force to the clamping/holding points, - introducing the contact surface (6) in the form of a cone into the union nut (5), - loosening the clamping of the union nut (5), - screwing the union nut (5) with the internal thread (7) onto the external thread (3), - establishing the operative connection between the contact surface (6) of the union nut (5) and a conical contact surface of the collet (4). Holder for a tool and/or a workpiece, with a collet holder (2) and an external thread (3) as well as a collet (4) and a union nut (5) which has a contact surface (6) and an internal thread (7), wherein the contact surface (6) is operatively connected to the collet (4) and the internal thread (7) is operatively connected to the external thread (3), characterized in that the contact surface (6) of the union nut (5) is a cone which is at least partially elliptical and that the internal thread (7) of the union nut (5) is also elliptical, wherein the ellipses are arranged rotated at an angle to one another about a central/rotational axis (L) of the union nut (5). Holder after Claim 2 , characterized in that the angle is approximately 90°. Holder after Claim 2 or 3 , characterized in that the collet holder (2) has an inner cone (8). Holder according to at least one of the preceding claims, characterized in that the collet (4) has the shape of a double cone. Holder according to at least one of the preceding claims, characterized in that the collet (4) is radially slotted.

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