DE102017130643A1 - Adjustment screw for a tool holder - Google Patents

Abstract

The invention relates to an adjusting screw (20) for a tool holder, comprising a base body (23) having an external thread (24) and having a head portion (26) formed at its tool end, and a spring element (34) for yielding support Tool shank, wherein on the head portion (26) a metallic support ring (28) is held, wherein a tool side of the support ring (28, 28a) as a support surface (42) for the tool shank (16) is formed, and wherein a machine side of the support ring (28 ) is formed for abutment of the spring element (34).

Description

The invention relates to an adjusting screw for a tool holder, having a base body which has an external thread and at the werkzeugseitigem end a head portion is formed, and with a spring element for the resilient support of a tool shank.

Such an adjusting screw is from the DE 10 2009 040 173 A1 known.

As the chuck portion of a shrink chuck cools, it shrinks, forming a high strength frictional engagement with the tool shank. For axial support of the shaft tool in a shrink chuck, an adjusting screw is used, via which an axial position of the tool in the shrink chuck can be adjusted continuously.

Since the shrinkage process, the dimensions of the clamping section change not only in the radial, but also in the axial direction, due to the axial shortening of the clamping section creates an axial force acting on the adjusting screw.

In the prior art, this usually consisting of tool steel adjusting screws are rotated back by a certain amount to absorb the axial change in length during the shrinking process.

In the aforementioned DE 10 2009 040 173 A1 a compensating portion of a plastic deformable material such as brass or copper is used. Alternatively, a spring element or an elastomer may be provided approximately in the form of an elastomeric ring, which is arranged in each case between the adjusting screw and the tool shank.

The compensation section is preferably formed by a coated section of the adjustment section. Due to the compensation section a high concentricity is to be made possible despite production-related errors in the tool or chuck.

However, the known arrangement requires a relatively complicated handling, if a separate elastomeric ring or a spring element is used, or leads to a complex production, if the elastomer is to be applied to the tool side of the adjusting screw.

Although the well-known adjustment allows a certain progress, so the production and installation is still relatively expensive. Furthermore, there are still disadvantages if the adjusting screw is not adjusted correctly.

Collet chucks have similar problems. After the collet frictionally clamps the tool shank, a fairly large Axialweg is still covered to the final position. Again, a compensation would be useful by a resilient adjusting screw.

Against this background, the invention has the object to improve an adjusting screw for a tool holder of any kind such that an axial compliance is ensured during the clamping process that the simplest and most cost-effective production is possible and that further safe and reliable handling is guaranteed.

This object is achieved according to the invention in an adjusting screw according to the type mentioned above, that on the head portion a metallic support ring is held, that a tool side of the support ring is formed as a support surface for the tool, and that a machine side of the support ring is formed for abutment of the spring element ,

The object of the invention is completely solved in this way.

According to the invention, a compliance in the adjusting screw is fully integrated by the spring element, which ensures a very simple handling and ensures reliable functioning. Since the direct support of the tool shank is effected by the metal ring, a clean support and guidance of the tool shank is guaranteed in any case. In contrast, the tool-side support with a spring element according to the prior art could lead to tilting or run-out deviations nevertheless occurring.

The tool holder can basically be any tool holder. In particular, the adjusting screw in combination with tool holders in the form of a shrink chuck or in the form of a collet chuck is advantageously used.

The adjusting screw according to the invention can also be used advantageously in particular in connection with collet chucks. Especially with collet chucks after clamping of the tool shank in the radial direction is still a relatively large Axialhub, which must be considered in a rigid adjusting screw by a prior adjustment of the adjusting screw.

In this case, the adjusting screw according to the invention, which can be used universally in conjunction with tool holders, creates a considerable improvement.

According to a further embodiment of the invention, the spring element is formed as an elastomer.

This allows a particularly simple and inexpensive construction.

According to a further embodiment of the invention, the spring element is designed in the form of an elastomeric ring, which is arranged between the head portion of the base body and the machine side of the support ring.

In this way, results in a simple and inexpensive production.

In an additional development of this embodiment, the elastomeric ring is received between an end face of the head section and an annular groove of the support ring.

This allows easy attachment. In addition, a single body can be used if different support rings are to be used for different designs.

According to a further embodiment of the invention, the spring element with the support ring or the head portion is firmly connected.

Here, the spring element may be formed as an elastomer, which is vulcanized about on the support ring or the head portion.

This allows a particularly durable attachment.

According to a further embodiment of the invention, the support ring is secured to the head portion by means of a latching connection.

In this way, the base body can be easily coupled to various support rings, e.g. Different designs for normal lubrication and minimum quantity lubrication (MQL), for shrink chucks, for collet chucks and other chucks.

This allows a particularly simple and inexpensive production.

According to one embodiment of the invention for this purpose the support ring is provided with an elastically expandable sleeve portion which can be pressed over a radially projecting holding portion of the head portion on the head portion until the support ring with an undercut on the holding portion is axially movable, but held captive.

This allows easy mounting of the support ring on the base body with the spring element arranged therebetween.

According to a further embodiment of the invention, the support ring on an annular shoulder, which is formed at fully compressed spring element for positive engagement with the head portion of the body.

In this way, a positive engagement is ensured in case of overload or failure of the spring element.

With the invention, a tool holder is further provided with an adjusting screw according to the manner described above.

In particular, in this case the tool holder can be designed in the form of a shrink chuck or in the form of a collet chuck.

It is understood that the features of the invention mentioned above and those yet to be explained below can be used not only in the particular combination indicated but also in other combinations or in isolation, without departing from the scope of the invention.

• 1 eine Werkzeugaufnahme in Form eines Schrumpfspannfutters mit einer erfindungsgemäßen Einstellschraube und einem Werkzeugschaft, der in einem Schrumpfabschnitt des Spannfutters aufgenommen ist, in einer teilweise geschnittenen Seitenansicht;
• 2 eine vergrößerte Darstellung der Einstellschraube gemäß 1 in einer Längsansicht;
• 3 einen Längsschnitt durch die Stellschraube gemäß 2;
• 4 den Grundkörper, den Elastomerring und den Stützring gemäß 3 vor dem Zusammenbau in perspektivischer Explosionsdarstellung;
• 5 die Einstellschraube gemäß 4 nach dem Zusammenbau der Einzelteile in perspektivischer Darstellung;
• 6 eine Längsansicht einer weiteren Ausführung einer Einstellschraube in einer leicht gegenüber 2 abgewandelten Ausführung und
• 7 einen Längsschnitt durch die Einstellschraube gemäß 6.

Further features and advantages of the invention will become apparent from the following description of preferred embodiments with reference to the drawings:
Show it:

• 1 a tool holder in the form of a shrink chuck with an adjusting screw according to the invention and a tool shank, which is received in a shrinkage section of the chuck, in a partially sectioned side view;
• 2 an enlarged view of the adjusting screw according to 1 in a longitudinal view;
• 3 a longitudinal section through the screw according to 2 ;
• 4 the main body, the elastomeric ring and the support ring according to 3 before assembly in perspective exploded view;
• 5 the adjusting screw according to 4 after assembly of the items in perspective view;
• 6 a longitudinal view of another embodiment of an adjusting screw in a slightly opposite 2 modified version and
• 7 a longitudinal section through the adjusting screw according to 6 ,

In 1 is a tool holder with an adjusting screw according to the invention total with numeral 10 designated.

The tool holder 10 In the case shown, a shrink chuck 12 with a thermally expandable shrink section 13 on, in which a tension opening 18 is provided.

In the case shown, the tool holder 10 also a clamping cone 14 for clamping or for handling the tool holder 10 on.

At the in 1 shown shrink chuck 12 it is a shrink chuck with a central passage 25 for minimum quantity lubrication. For minimum quantity lubrication, the adjustment screw must be 20 opposite a conical shoulder surface 17 of the tool shank 16 be configured sealing.

The location of the tool shank 16 when clamping is achieved by an axial adjustment of the adjusting screw 20 in an associated threaded hole 22 of the shrink chuck 12 established.

In order to absorb the thermally induced changes in length, due to the axial shortening of the shrinkage section 13 can lead to an axial force on the adjusting screw during cooling, according to the invention, the adjusting screw 20 provided with a spring element, which is preferably formed as an elastomer.

In this way, adverse axial forces can be avoided and at the same time can be a precise positioning of the tool shank 16 be ensured within the clamping section. Furthermore, a high concentricity is achieved.

2 shows an enlarged view of the adjusting screw 20 according to 1 ; a sectional view is in 3 shown. The adjusting screw 20 consists of three parts, namely a basic body 23 , with an external thread 24 is provided, from a metallic support ring 28 and a spring element 34 in the form of an elastomeric ring. The support ring 28 is under the interposition of the spring element 34 on a tool-side head section 26 of the basic body 23 held.

The tool-side support surface 42 of the support ring 28 is the shape of the tool shank 16 according to 1 adapted to ensure a seal with minimum quantity lubrication. For this purpose, the support surface 42 formed in the form of a hollow cone, so that this with the conical shoulder surface 17 of the tool shank 16 seals.

The support ring 28 is on the head section 26 of the basic body 23 received by means of a latching connection. This is at the head section 26 a holding section 38 provided with a radial extension, with an undercut 40 at an associated sleeve area 36 of the support ring 28 interacts.

The approximately consisting of tool steel support ring 28 is in his pod area 36 sufficiently thin and elastic, so that, as in 4 through an arrow 40 indicated, the support ring 28 with the interposition of the spring element 34 on the head section 26 can be pressed until the undercut 40 at the holding section 38 of the head section 26 locks. Here, the position of the spring element 34 through an annular groove 32 on the support ring 28 specified.

In this position, the support ring 28 with the interposition of the spring element 34 captive on the head section 26 held with a certain bias. The main body 23 preferably also consists of tool steel, while the spring element may consist of a polyurethane for example.

From the in 3 shown, unloaded basic position, the support ring 28 under the action of an axial force against the spring action of the spring element 34 move to the left (in the machine direction), but not more than one shoulder 33 ( 3 ) of the support ring 28 at the frontal area 30 of the basic body 23 comes to the plant and thus ensures a positive connection.

In normal operation, while tensioning and relaxing, but no positive connection. The axial end position is rather by the compressed spring element 34 specified.

The 6 and 7 show one opposite the 2 and 3 modified version of the adjusting screw, the total with 20a is designated.

Here, for modified parts, reference numerals are used, which are followed by the letter a, while corresponding reference numerals are used for corresponding parts.

The adjusting screw 20a has the identical basic body 23 on, as previously based on the 2 and 3 described.

Only the support ring 28a is modified as the adjusting screw 20a in the present case is not intended for minimum quantity lubrication, but for normal lubrication. In this case, a plane support surface 42a for axial support of the tool shank 16 intended.

Incidentally, the structure of the support ring corresponds 28a the structure of the support ring described above 28 , Again, the support ring 28a with the interposition of the spring element 34 by the latching connection on the head section 26 of the basic body 23 attached.

It is understood that in 1 illustrated tool holder 10 is merely exemplary nature. The adjusting screw according to the invention 20 or. 20a Can be used for any toolholders to the axial position of a tool shank 16 set. In addition to an application in shrink chucks 12 according to 1 In particular, an application in collet chucks is particularly advantageous.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102009040173 A1 [0002, 0006]

Claims (11)

Adjusting screw (20, 20a) for a tool holder (10), with a base body (23) having an external thread (24) and at its tool-side end a head portion (26) is formed, and with a spring element (34) for resilient support a tool shank (16), characterized in that on the head portion (26) a metallic support ring (28, 28a) is held, that a tool side of the support ring (28, 28a) as a support surface (42, 42a) for the tool shank (16) is formed, and that a machine side of the support ring (28, 28 a) is formed for abutment of the spring element (34). Adjusting screw (20, 20a) after Claim 1 , characterized in that the spring element (34) is designed in the form of an elastomer. Adjusting screw (20, 20a) after Claim 1 or 2 , characterized in that the spring element (34) is designed in the form of an elastomeric ring, which is arranged between the head portion (26) of the base body (23) and the machine side of the support ring (28, 28a). Adjusting screw (20, 20a) after Claim 3 , characterized in that the spring element (34) between an end face (30) of the head portion (26) and an annular groove (32) of the support ring (28, 28 a) is received. Adjusting screw (20, 20a) after Claim 1 , characterized in that the spring element (34) with the support ring (28, 28 a) or the head portion (26) is firmly connected. Adjusting screw (20, 20a) after Claim 5 , characterized in that the spring element (34) is an elastomer which is vulcanized onto the support ring (28, 28a) or the head section (26). Adjusting screw (20, 20a) according to one of the preceding claims, characterized in that the support ring (28, 28a) is secured to the head section (26) by means of a latching connection (38, 40). Adjusting screw (20, 20a) after Claim 6 , characterized in that the support ring (28, 28a) has an elastically expandable sleeve portion (36) which can be pressed over a radially projecting holding portion (38) of the head portion (26) on the head portion (26) until the support ring (28 , 28a) with an undercut (40) on the holding portion (38) axially movable, but is held captive. Adjusting screw (20, 20a) according to one of the preceding claims, characterized in that the support ring (28, 28a) has an annular shoulder (33) which, when the spring element (34) is fully compressed, fits positively against the head portion (26) of the base body (23 ) is trained. Tool holder (10) with an adjusting screw (20, 20a) according to one of the preceding claims. Tool holder (10) after Claim 10 , which is in the form of a shrink chuck or in the form of a collet chuck.

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