MODULAR TOOL AND METHOD FOR EJECTING AN INSERT OF A MODULAR TOOL

The invention relates to a modular tool comprising a body and an insert for machining a workpiece, wherein the insert comprises a tenon for insertion into a receptacle of the body, wherein the body comprises an access hole, through which the tenon is accessible for an assembly tool, wherein the tenon comprises a profile portion, which, upon insertion of the assembly tool into the access hole, engages with a lateral surface of the assembly tool so that, by a rotation of the assembly tool, the insert can be ejected from the receptacle. Furthermore, a method for ejecting an insert of such a modular tool is specified.

RELATED APPLICATION DATA

The present application claims priority under 35 U.S.C. § 119 to German Patent Application No. 1020222137787, filed on Dec. 16, 2022, which is incorporated by reference herein in its entirety.

FIELD

The invention relates to a modular tool and a method for ejecting an insert of such a modular tool.

BACKGROUND

A modular tool is configured in at least two pieces and typically comprises a body to be clamped into a tool mount of a machine tool and an insert that is in turn inserted into the body. The insert is then used for the actual machining of a workpiece.

The insert is replaceable in principle, and this is a significant advantage of a modular tool compared to a non-modular tool. However, in operation, i.e., during the machining of a workpiece, the insert must be seated as firmly and definedly in the body as possible in order to ensure correct machining. Accordingly, a removal of the insert can be difficult if, for example, it is clamped in the body.

A rotary cutting tool is described in DE 10 2013 102 901 A1, which comprises: an exchangeable cutting tip having a first threaded portion and a tool body having a second threaded portion which cooperatively engages with the first threaded portion, wherein the second threaded portion can be moved relative to the tool body in a manner that selectively couples the cutting tip to the tool body.

In light of this, the problem addressed by the invention is to simplify removal of the insert from the body in the case of a modular tool. A correspondingly improved modular tool as well as a corresponding method for ejecting an insert are to be specified for this purpose.

SUMMARY

The problem is solved according to the invention by a modular tool having the features according to claim1and by a method having the features according to claim12. Advantageous configurations, further developments, and variants are the subject matter of the subclaims. The statements made in connection with the modular tool also apply to the method and vice versa.

A core concept of the invention is in particular to configure the use of a modular tool such that it can be ejected using a simple and preferably standardized assembly tool, e.g., a screwdriver.

A modular tool according to the invention comprises a body and an insert. The body serves in particular to assemble the modular tool in a tool mount, e.g., a chuck, of a machine tool. The insert serves to machine a workpiece. The insert is in particular a cutting insert for machining a workpiece. During the machining, the insert and the body are fixedly connected to one another. However, the insert is generally releasable in order to be replaced with a new insert, e.g., in the event of wear.

The modular tool generally extends along a longitudinal axis in a longitudinal direction. Preferably, the modular tool is a rotary tool that is rotatable about an axis of rotation for machining a workpiece. In other words, the longitudinal axis is also an axis of rotation about which the modular tool rotates while in operation. Such a design is assumed below without limiting its generality.

Particularly preferred is a configuration in which the modular tool is a drill having one or more main cutting edges formed on the insert. In a suitable embodiment, the insert is a so-called cutting plate, i.e., is plate-shaped with two cutting edges.

The insert comprises a tenon for insertion into a receptacle of the body. The tenon preferably extends along the axis of rotation, i.e., in the axial direction. To machine the workpiece, the insert also comprises in particular a head, to which the tenon connects, in particular in the longitudinal direction. Preferably, especially in the case of a rotary tool, the tenon extends along the longitudinal axis, i.e., in particular concentrically to the body. The same applies analogously for the receptacle. The tenon and the receptacle are preferably generally cylindrical. In the assembled state, the tenon is seated in the receptacle and the insert is attached to the body. The head has a length preferably corresponding to 0.5-fold to 2-fold of a length of the tenon. Typically, the head and the tenon are approximately the same length.

The body comprises an access hole, through which the tenon is accessible for an assembly tool. The access hole extends preferably transversely to the axis of rotation, i.e., in a radial direction. The assembly tool is, for example, a screwdriver. The assembly tool can be actuated manually or by a robot. The tenon is generally inserted into the body and then surrounded and in particular also obscured by it. The access hole now represents an opening in the body through which the tenon is nevertheless accessible, at least for the assembly tool. Suitably, the body has a lateral surface, which extends in particular around the longitudinal axis, and the access hole lies in the lateral surface of the body. The access hole is suitably a blind hole, but this is not mandatory, and a through-hole is also generally suitable. In one suitable design, the access hole passes by the tenon, but in another suitable design, the access hole leads onto the tenon. The access hole is suitably circular, but a round hole is also generally suitable.

The tenon comprises a profile portion, which, upon insertion of the assembly tool into the access hole, engages with a lateral surface of the assembly tool so that, by a rotation of the assembly tool, the insert can be ejected from the receptacle, in particular on the front side, i.e., forward in the longitudinal direction. In other words: to eject the insert, the assembly tool is inserted into the access hole so that the lateral surface of the assembly tool then engages with the profile portion of the tenon and thus, by subsequently rotating the assembly tool, the insert is ejected from the receptacle. The access hole itself serves in particular as a counter-bearing against which the assembly tool is supported during a rotation, so that the tenon and correspondingly the entire insert are moved relative thereto, in particular in the longitudinal direction.

The profile portion is a core aspect of the present invention and advantageously allows the ejection of the insert with a simple assembly tool. The profile portion is arranged laterally on the tenon, i.e., on a lateral surface of the tenon, and is accessible for the assembly tool via the access hole. The profile portion is preferably shaped complementary to the lateral surface of the assembly tool in order to ensure as optimum an engagement as possible. When the assembly tool is inserted into the access hole, the lateral surface of the assembly tool extends in particular from the side into the profile portion.

The specific configuration of the lateral surface of the assembly tool is dependent in particular upon the configuration of the latter. With a screwdriver as the assembly tool, the latter comprises a tip, which is configured so as to engage with a tool engagement portion of a screw head. In the present case, a screwdriver is assumed to be the assembly tool, without limiting its generality. Depending on the front profile (also cross-section) and the circumferential contour (also tool contour) of the tip, varying lateral surfaces of the assembly tool may then result. However, the lateral surface is generally characterized by a plurality of edges and/or ribs, which are particularly suitable for engaging with the profile portion.

Preferably, the assembly tool has an at least four-fold rotational symmetry, in particular with respect to its front profile and then consequently also with respect to its lateral surface. Accordingly, the lateral surface of the assembly tool has at least four edges. This is the case, for example, with a Phillips screwdriver. Particularly preferred is an assembly tool having a six-fold rotational symmetry, e.g., a hexagonal or six-lobe screwdriver having a lateral surface with six edges/ribs.

The invention in particular makes use of the finding that an assembly tool can be used not only with its front profile, but the front profile also leads to a gear-like lateral surface equipped with edges or ribs. This is advantageously used in the manner of a gear for engaging with a correspondingly configured profile portion of the tenon in order to ultimately drive it, i.e., move it linearly. In this way, a tool-assisted ejection of the insert is realized, which in turn makes it particularly easy to remove a possibly clamped or even jammed insert from the body in a simple manner. In this way, an exchange of the insert is also accordingly simplified. Above all, it is now not necessary to remove the modular tool in order to eject the insert from the tool mount, i.e., an exchange of the insert can be performed while the modular tool is mounted in the tool mount.

Particularly preferred is a configuration in which, due to the profile portion, the tenon is formed in the manner of a rack in order to form, together with the assembly tool, a rack drive for ejecting the insert. The assembly tool, specifically its tip, forms a gear with which the tenon is driven. Accordingly, the profile portion comprises a plurality of teeth and grooves, which are preferably parallel to one another, for engaging with the assembly tool, more precisely with the lateral surface thereof. The grooves and teeth either run perpendicular to the tenon overall or at a non-perpendicular angle thereto. During the retraction, the edges/ribs of the lateral surface of the assembly tool laterally retract into the grooves, i.e., the assembly tool is not mounted on the profile portion from above, so to speak, but instead gradually extends perpendicularly or at a non-perpendicular angle into the profile portion, as it were. Because this assembly tool is supported in the access hole during the rotation, the tenon is driven out of the receptacle accordingly. Suitably, the profile portion comprises at least 2 grooves and/or at most 10 grooves. The exact number of grooves will depend in particular on the size of the insert and the assembly tool as well as the required displacement path for the insert.

Preferably, the insert can be inserted into the body on the front side, and the body comprises for this purpose a seat on the front side with two arms between which the insert is held. Here, “front side” is understood to mean “facing the workpiece.” When assembled, the insert is inserted into the body and received by the seat and is encompassed by the arms. The seat is in particular U-shaped in a cross-section along the longitudinal axis, wherein the two arms form the two legs of the U and a base of the seat forms the base of the U connecting the arms together. The receptacle for the tenon is arranged in the base, in particular. The arms are preferably formed with an interference fit, so that the insert is firmly clamped between the arms.

Expediently, the modular tool comprises a releasable clamping mechanism for firmly clamping the insert. The clamping mechanism suitably comprises a clamping element, preferably a clamping screw, which is inserted into the body and engages with the tenon for firm clamping. Accordingly, the clamping mechanism is arranged overall in particular in a front-side half of the modular tool. For the clamping element, the tenon suitably comprises a recess into which the clamping element engages for the purpose of clamping. Expediently, the clamping mechanism is even configured such that it pulls the insert into the seat upon actuation. In this way, any resistance (e.g., due to the aforementioned interference fit) is overcome without having to push on the insert on the front side. In a suitable configuration, the clamping element is inserted obliquely (e.g., at an angle of 20° to 70° to the longitudinal axis) into the body, and the tenon has a corresponding slope on its lateral surface against which the clamping element presses when actuated in order to clamp the insert. In this way, an axial force can be generated via an access proceeding from the lateral surface of the body in order to firmly clamp the insert in the longitudinal direction. The slope is suitably formed by the aforementioned recess, which, for example, is trapezoidal when viewed in a cross-section along the longitudinal axis. For example, the recess is a simple groove.

The profile portion is preferably arranged between the head of the insert and the recess for the clamping element. In particular, this avoids the clamping mechanism being too close to the tip of the modular tool.

The clamping element can generally be actuated by an assembly tool, in particular also by a rotation of the assembly tool, which is, for example, a screwdriver. In a particularly advantageous design, the clamping element can be actuated by the assembly tool, with which the insert is also ejected. Accordingly, a similar or even the same assembly tool can advantageously be used in two ways, namely once for actuating the clamping mechanism and once for ejecting the insert.

In an advantageous configuration, the modular tool is configured such that the clamping element is automatically actuated by the assembly tool and thereby the clamping mechanism is released when the assembly tool is inserted into the access hole. With its front profile, the assembly tool abuts the clamping element in particular at the end of the access hole, which is thereby pushed out of the tenon and generally radially outward and releases the tenon for a movement in the longitudinal direction. The clamping element is expediently spring-loaded, in the present case by means of a spring, so that the assembly tool is operated against the spring. Subsequently, the insert is then ejected by a rotation of the assembly tool. Subsequently, a new insert can be introduced. As the assembly tool is removed from the access hole, the clamping element is then automatically retracted back into the tenon, if provided.

The tenon of the insert has a two-fold rotational symmetry, i.e., it is rotatable about the longitudinal axis by 180° and can be inserted into the body in two orientations. This is particularly advantageous with correspondingly symmetrical cutting plates, whose orientation cannot be readily be viewed. Due to the rotational symmetry, regardless of how the insert is used, an ejection and in particular firm clamping is possible in both orientations, even if the body only comprises a single access hole and optionally a single clamping element. Preferably, the insert as a whole (and in particular also the seat for it) has a two-fold rotational symmetry.

In a suitable configuration, the receptacle for the tenon is an end portion of a media channel of the body, i.e., a channel for a coolant and/or lubricant. The tenon then closes the media channel on the front side. In particular, the body comprises one or more lateral media outlets, which are connected to the media channel. The media channel extends through the body in the longitudinal direction and preferably along the longitudinal axis. A medium is input into the media channel in particular on the rear side of the body. One particular advantage of the ejection described herein is that the media channel no longer has to be used in order to also introduce an assembly tool for ejecting the insert, rather it is free of this and can thus be designed solely depending on the requirements of a media guidance. This results from the profile portion and the arrangement of the access hole and also applies wholly irrespective of whether the receptacle for the insert is part of the media channel.

In addition to ejecting the insert, the tenon with the profile portion and the assembly tool can advantageously be used inversely for the retraction of the insert into the body by simply rotating the assembly tool in the reverse direction.

The problem is also solved in particular by the combination of a modular tool and an assembly tool as described, as well as separately from one another by an insert and a body of a modular tool as described.

DETAILED DESCRIPTION

The modular tool2comprises a body4and an insert6. The body4serves for assembly of the modular tool2in a tool mount (not shown) on a tool machine (also not shown). The insert6serves for machining a workpiece (not shown), and in the present case is a cutting insert. During the machining, the insert6and the body4are fixedly connected to one another. However, the insert6is generally releasable. An exemplary embodiment for the insert6is shown inFIG.9in three different views.

The modular tool2generally extends along a longitudinal axis A in a longitudinal direction L. The modular tool2shown by way of example here is a rotary tool, in which the longitudinal axis A is simultaneously an axis of rotation. In addition, the modular tool2shown by way of example here is a drill having one or more (here two) main cutting edges8, which are formed on the insert6. More specifically, the insert6shown here is a so-called cutting plate.

The insert6comprises a tenon10for insertion into a receptacle12of the body4. To machine the workpiece, the insert6comprises a head14, to which the tenon10connects in the longitudinal direction L. The tenon10extends along the longitudinal axis L and concentrically to the body4. The same applies analogously for the receptacle12. The tenon10and the receptacle12are generally cylindrical. In the assembled state, the tenon10is seated in the receptacle12and the insert6is attached to the body4. In the present case, the head14and the tenon10are approximately the same length.

The body4has an access hole16through which the tenon10is accessible for an assembly tool18, for which an exemplary embodiment is shown inFIGS.1a,1b,1cand which is also visible inFIGS.2,5, and6. InFIGS.1ato2, the assembly tool18is shown in duplicate, because the same assembly tool18is used for two different tasks, as will be explained further below. The access hole16runs transversely to the axis of rotation, i.e., in the radial direction R. In the present case, the assembly tool18is a screwdriver, more specifically a six-lobe screwdriver. The assembly tool18can be actuated manually or by a robot. The tenon10is generally inserted into the body4and then surrounded and also obscured by it. The access hole16now represents an opening in the body4through which the tenon10is nevertheless accessible, at least for the assembly tool18. This can be seen particularly clearly inFIGS.5,6, and7. The access hole16and a front profile20of the assembly tool18as well as their position relative to the tenon10can also be seen. The access hole16lies in the lateral surface22of the body4. The access hole16shown here is a blind hole, but this is not mandatory. In addition, the access hole16shown here passes by the tenon10, but this is also not mandatory.

The tenon10comprises a profile portion24, which, upon insertion of the assembly tool18into the access hole16, engages with a lateral surface26of the assembly tool18so that, by a rotation D1of the assembly tool18, the insert6can be ejected from the receptacle12. In other words: to eject the insert6, the assembly tool18is inserted into the access hole16so that the lateral surface26of the assembly tool18then engages with the profile portion24of the tenon10and thus, by subsequently rotating the assembly tool18, the insert6is ejected from the receptacle12. The access hole16itself serves as a counter-bearing against which the assembly tool18is supported during a rotation D1(cf.FIG.5), so that the tenon10and correspondingly the entire insert6are moved relative thereto, namely in the longitudinal direction L.

The profile portion24is shaped complementary to the lateral surface26of the assembly tool18and allows the ejection of the insert6with a simple assembly tool18. The profile portion24is arranged laterally on the tenon10, i.e., on a lateral surface28of the tenon10, and is accessible for the assembly tool18via the access hole16.

The specific configuration of the lateral surface26of the assembly tool18is dependent upon the configuration of the latter. In the screwdriver shown here, the assembly tool18comprises a tip, which is configured so as to engage with a tool engagement portion of a screw head. Depending on the front profile20and circumferential contour of the tip, varying lateral surfaces26of the assembly tool18may then result. However, the lateral surface26is generally characterized by a plurality of edges and/or ribs30, which are particularly suitable for engaging with the profile portion24.

The assembly tool18has an at least four-fold, even six-fold rotational symmetry with respect to its front profile20and then consequently also with respect to its lateral surface26. Accordingly, the lateral surface26of the assembly tool18has at least four, here six edges30.

As can be seen in particular inFIGS.5,6, and9, in the configuration shown here, due to the profile portion24, the tenon10is formed in the manner of a rack in order to form, together with the assembly tool18, a rack drive for ejecting the insert6. The assembly tool18, specifically its tip, forms a gear with which the tenon10is driven. The profile portion24correspondingly comprises a plurality of teeth and grooves32parallel to one another for engaging with the lateral surface26of the assembly tool18. Because it is supported in the access hole16during the rotation D1, the tenon10is driven out of the receptacle12accordingly. The profile portion24shown here comprises four grooves32, but other numbers are also possible.

The insert6can be inserted into the body4on the front side, and the body4comprises for this purpose a seat34on the front side with two arms36between which the insert6is held. Here, “front side” is understood to mean “facing the workpiece.” When assembled, the insert6is inserted into the body4and received by the seat6and is encompassed by the arms36. The seat34is U-shaped in a cross-section along the longitudinal axis A, wherein the two arms36form the two legs of the U and a base38of the seat34forms the base of the U connecting the arms34together. The receptacle12for the tenon10is arranged in the base38. In the present case, the arms34are formed with an interference fit, so that the insert6is firmly clamped between the arms34.

The modular tool2shown here further comprises a releasable clamping mechanism40for firmly clamping the insert6. The clamping mechanism40comprises a clamping element42, here a clamping screw (recognizable inFIG.4), which is inserted into the body4and engages with the tenon10for the purpose of firm clamping. The clamping mechanism40is arranged overall in a front-side half of the modular tool2. For the clamping element42, the tenon10comprises a recess44into which the clamping element42engages for the purpose of clamping. The clamping mechanism40shown here is even configured such that it pulls the insert6into the seat34upon actuation. The clamping element42is also inserted obliquely into the body4, and the tenon10has a corresponding slope46on its lateral surface28against which the clamping element42presses when actuated in order to firmly clamp the insert6. In this way, an axial force can be generated via an access proceeding from the lateral surface22of the body4in order to firmly clamp the insert6in the longitudinal direction L. In the present case, the slope46is formed by the aforementioned recess44, which in the present case is a trapezoidal groove when viewed in a cross-section along the longitudinal axis A. In the present case, between the recess44and the head14, the profile portion24is arranged.

The clamping element42can generally be actuated by an assembly tool18, in the present case also by a rotation D2of the assembly tool18, which has already been described. Thus, in the present case, a similar or even the same assembly tool18can be used in two ways, namely once for actuating the clamping mechanism40and once for ejecting the insert6.

The insert6, and in particular the tenon10, have a two-fold rotational symmetry in the exemplary embodiment shown, i.e., it can be rotated by 180° about the longitudinal axis A and can be inserted into the body4in two orientations.

The receptacle12for the tenon10in the configuration shown here is an end portion of a media channel48of the body4, i.e., a channel for a coolant and/or lubricant. The tenon10then closes the media channel48on the front side. The body4here comprises one or more lateral media outlets50, which are connected to the media channel48. The media channel48extends through the body4in the longitudinal direction L and along the longitudinal axis A. A medium is input into the media channel48on the rear side of the body4.

In addition to ejecting the insert6, the tenon10with the profile portion24and the assembly tool18can be used inversely for the retraction of the insert6into the body4by simply rotating the assembly tool in the reverse direction.

In an alternative configuration, not explicitly shown, the modular tool2is configured such that the clamping element42is automatically actuated by the assembly tool18and thereby the clamping mechanism40is released when the assembly tool18is inserted into the access hole16. With its front profile20, the assembly tool abuts the clamping element42at the end of the access hole16, which is thereby pushed out of the tenon10and generally radially outward and releases the tenon10for a movement in the longitudinal direction L. The clamping element42is spring-loaded, for example by means of a spring, so that the assembly tool18is operated against the spring. The insert6is subsequently ejected by a rotation D1of the assembly tool18. Subsequently, a new insert6can be introduced. As the assembly tool18is removed from the access hole16, the clamping element42is then automatically retracted back into the tenon10.