CN112236258A

CN112236258A - Chuck with a locking mechanism

Info

Publication number: CN112236258A
Application number: CN201980038630.9A
Authority: CN
Inventors: A·恩勒
Original assignee: Rohm Co Ltd
Current assignee: Rohm Co Ltd
Priority date: 2018-06-12
Filing date: 2019-05-28
Publication date: 2021-01-15
Also published as: DE102018113947A1; EP3774139A1; WO2019238413A1

Abstract

The invention relates to a chuck for a machine tool, comprising a chuck body (4), a plurality of jaws (2) arranged in radial guide grooves (3) of the chuck body (4), and a wedge rod (6) driving the jaws (2), wherein the wedge rod (6) can slide in the chuck body (4) in a wedge rod recess (5) transversely to the guide grooves (3). The wedge bars can be inserted into corresponding tooth gaps (9) of the jaws (2) by means of a row of teeth (8) to form a helical toothing. In a receptacle (10) extending from the outer circumferential periphery of the chuck body (4) to the wedge shank (6), a pin (11) is arranged which can be displaced relative to the receptacle (10), said pin having a first inclined surface (12) on the side facing the wedge shank (6) for terminating the toothed engagement between the tooth row (8) and the tooth gap (9) when the pin (11) is displaced out of its rest position. On the side of the wedge lever (6) facing away from the row of teeth (8), a slide (13) is arranged, which is operatively connected to the bolt (11) and has a second inclined surface (14) for forming a toothed engagement when the bolt (11) is reset into its rest position.

Description

Chuck with a locking mechanism

Technical Field

The invention relates to a chuck for a machine tool, comprising a chuck body, a plurality of jaws arranged in radial guide grooves of the chuck body, and a wedge rod driving the jaws, which is slidable transversely to the guide grooves in a wedge rod recess in the chuck body, and which engages with a row of teeth in corresponding tooth gaps of the jaws to form a helical toothing.

Background

Such a chuck is known from DE 19930784 a1, which has proven to be very good in practice, but which places high demands on the manufacture in terms of its structure and the complexity of the components used and is correspondingly expensive.

Disclosure of Invention

The object of the present invention is therefore to design a chuck of the type mentioned at the outset in such a way that it can be produced more cost-effectively.

In a chuck of the type mentioned at the outset, this object is achieved in that a pin which is displaceable relative to the receptacle and has a first inclined surface on the side facing the wedge rod is arranged in the receptacle extending from the outer circumference of the chuck body to complete the toothing engagement between the tooth row and the tooth gap when the pin is displaced out of its rest position, and in that a slide which is in operative connection with the pin and has a second inclined surface for forming the toothing engagement when the pin is reset into its rest position is arranged on the side of the wedge rod facing away from the tooth row.

The chuck according to the invention is characterized by its structural simplicity with respect to the components for the chuck quick-change system, since it is sufficient for each jaw to manually operate a cotter which ends with its inclined face in a toothed engagement between the wedge rod and the associated jaw, so that the jaw can be displaced in and removed from the guide groove. The second inclined surface associated with the slide ensures a secure renewed toothing between the wedge rod and the pawl. As a result, only a small number of components are required for the chuck quick-change system, which components can moreover be produced cost-effectively.

The operational safety of the quick chuck changing system, which is designed in the chuck, is increased if a first counter surface, which is adapted to the shape of the first inclined surface, and/or a second counter surface, which is adapted to the shape of the second inclined surface, is designed on the wedge rod. In principle, it is sufficient for the first and second inclined surfaces to each exert the force required for displacement on the associated component in the manner of a line contact; however, it is preferred that the counter surfaces are beveled, since this promotes operational safety and reduces wear.

It is possible to design the pin as a pin which can be displaced in the receptacle in a purely translatory manner and which has a first inclined surface as a wedge surface, since this makes possible a particularly simple guidance of the pin in the chuck body of the chuck. It is then expedient to provide a groove, into which the collar associated with the slide engages, on the side of the first inclined plane facing the outer circumference of the chuck body. The interlocking engagement of the flange in the groove thus results in a coordinated displacement of the bolt and the slide by means of a positive connection.

However, in this embodiment, there is alternatively also the possibility of the pin and the slide being constructed in one piece.

A further preferred embodiment is characterized in that the pin is formed as a cylinder with a spiral groove formed on the circumferential surface, into which a guide means arranged on the chuck body engages, and that an annular groove into which a collar associated with the slide engages is formed on the side of the first inclined surface facing the outer circumference of the chuck body. In this embodiment, a rotational displacement of the bolt is carried out in order to bring about the required translational displacement of the bolt by means of the control curve, i.e. the helical groove. The rotational displacement of the bolt provides the advantage here that the required force, i.e. the torque required for the displacement, can be applied in a simple manner at the required magnitude and gives the user precise control of the displacement movement. In this case, the annular groove serves in a similar manner to the groove in the translationally displaceable bolt for coupling with the slide by means of the associated flange.

The shape of the first counter surface and the second counter surface can be configured differently from one another here, since a hollow cone or a hollow truncated cone is provided for the first counter surface in the wedge web, while the second counter surface can be configured unchanged as a wedge surface.

If the annular groove does not extend around the entire circumference of the cylinder and the spiral groove extends in a region of the circumferential surface which is not provided with an annular groove, it is possible to form the pin as a cylinder in a particularly short structural form compared to embodiments in which the annular groove extends around the entire circumference and an axial alternation of the annular groove and the spiral groove on the surface of the cylinder is required.

For simple transmission of sufficiently large torques, it is provided that a wrench receptacle suitable for transmitting torques is formed in the end face of the cylinder facing the outer circumference of the chuck body. A wrench, in particular with a sufficiently long lever arm, can then be inserted into the wrench receptacle in order to rotate the cylinder with only a small expenditure of force for the user.

If the distance of the first inclined surface from the second inclined surface is dimensioned such that the second counter surface also abuts the second counter surface when the first inclined surface also abuts the first counter surface, it is ensured that the wedge rod can follow the movement of the bolt in the desired manner when the bolt is moved in translation due to the coupling with the flange of the slide.

There is also the possibility of forming the wedge rod in two parts: a wedge-shaped section with a wedge and a tooth section carrying a tooth row are coupled to each other in such a way that they can be height-adjusted relative to each other. This embodiment again offers advantages in production and also offers the advantage that, in comparison to the need to displace only smaller components with smaller masses by means of the pin, only the tooth segment has to be displaced in order to complete the toothing or the remanufacturing thereof, so that a smaller force or a smaller torque is sufficient.

In order to achieve a good guidance when the tooth section is displaced in height relative to the wedge section, it is provided that the wedge section and the tooth section have L-shaped coupling regions, which engage in one another.

In another embodiment, the slide is loaded by means of a spring element in the direction of the rest position, so that when the chuck quick-change system is not actuated, there are fixing means for the toothing engagement; furthermore, the return of the bolt into its rest position, in which the toothed engagement between the pawl and the wedge rod is ensured, is facilitated by the flange of the slide.

Drawings

The invention is explained in detail below with the aid of embodiments shown in the drawings; therein is shown

Fig. 1 shows a top view of a chuck with jaws arranged in radial guide grooves of the chuck body;

fig. 2 shows a view corresponding to fig. 1 without the chuck body and with only two of the three jaws present in this embodiment;

fig. 3 shows a view from the direction of arrow III in fig. 2;

fig. 4 shows a detail IV of fig. 3;

FIG. 5 shows a view corresponding to FIG. 2, wherein the cotter is manipulated;

fig. 6 shows a view from the direction of arrow VI of fig. 5;

fig. 7 shows a detail VII of fig. 6;

FIG. 8 shows a perspective view of a tooth segment of the wedge rod;

FIG. 9 shows a view of the side of the tooth segment of FIG. 8 facing the pin;

FIG. 10 shows a top view of the tooth segment of FIG. 8;

FIG. 11 shows a top view of the wedge section of the wedge rod;

FIG. 12 shows a perspective view of the wedge segment of FIG. 11;

FIG. 13 shows a perspective view of the slider;

FIG. 14 shows a side view of the slider of FIG. 13;

FIG. 15 shows a top view of the slider;

FIG. 16 shows a view of the radially inner side of the slider;

FIG. 17 shows a perspective view of a pin shaped as a cylinder;

FIG. 18 shows a partially transparent side view of the pin of FIG. 17;

FIG. 19 shows section XIX-XIX of FIG. 18;

FIG. 20 shows a top view of an end face of the pin in FIG. 17;

FIG. 21 shows a view corresponding to FIG. 17 of another embodiment of a pin shaped as a cylinder;

FIG. 22 shows a view of the pin bolt of FIG. 21 corresponding to FIG. 18;

fig. 23 shows section XXIII-XXIII in fig. 22;

FIG. 24 shows a view of the pin of FIG. 21 corresponding to FIG. 20;

FIG. 25 shows a side view of a chuck with a purely translationally adjustable pin;

fig. 26 shows a view corresponding to fig. 2 with an embodiment of a bolt that can be displaced purely in a translatory manner;

fig. 27 shows a view from the direction of arrow XXVII of fig. 26;

FIG. 28 shows a perspective view of an isolated pin that can be adjusted purely translationally;

FIG. 29 shows a side view of the pin of FIG. 28;

FIG. 30 shows a side view of the tooth section of the wedge rod on the side facing the cotter of FIG. 28;

FIG. 31 shows a perspective view of a unitary construction of a pin and a slide;

FIG. 32 shows a side view of the one-piece construction of the slider and the pin of FIG. 31;

FIG. 33 shows a view corresponding to FIG. 27 with a one-piece construction of a slider and a pin;

FIG. 34 shows a view of a one-piece wedge rod in its installed state;

fig. 35 shows a view from the direction of arrow XXXV in fig. 34;

FIG. 36 shows a perspective view of a one-piece wedge rod;

FIG. 37 shows a side view of the one-piece wedge rod of FIG. 36;

FIG. 38 shows a perspective view of a slider mated with a one-piece wedge bar, and

fig. 39 shows a side view of the slider of fig. 38.

Detailed Description

Fig. 1 shows a top view of a chuck 1 for a machine tool, which in the exemplary embodiment shown in the drawings has three jaws 2, which are arranged in radial guide grooves 3 of a chuck body 4 and can be displaced in the radial guide grooves 3 of the chuck body 4. The number of jaws 2 can vary here, and embodiments with a number of jaws 2 different from three are also conceivable. For adjusting the jaws 2, a wedge rod 6 which is displaceable transversely to the guide groove 3 and which can be adjusted by force actuation in a known manner is arranged in the wedge rod recess 5 in the chuck body 4, for which purpose a drive sleeve is arranged on the chuck body of the machine tool, which drive sleeve engages with drive teeth arranged on the drive sleeve in a diagonal groove 7 of the wedge rod 6 for forming a wedge drive, so that upon axial adjustment of the chuck piston an adjustment of the wedge rod 6 in the direction of a misalignment of the circular chuck body 4 (fig. 2), i.e. in the longitudinal direction of the wedge rod recess 5, is achieved. A toothing engagement is formed between the wedge rod 6 and the pawl 2 by arranging a helical toothing with a row of teeth on the wedge rod 6, into which a corresponding tooth gap 9 of the pawl 2 engages. As a result, when the wedge rod 6 is displaced as a result of the drive of the wedge rod 6 by the drive sleeve, a change in the radial position of the jaws 2 is produced as a result of the helical toothing.

In the chuck 1, a quick jaw exchange system is provided for quickly exchanging the jaws 2 in a simple manner, wherein, however, the jaws 2 fitted in the guide grooves 3 can also be quickly adjusted to set significantly different clamping diameters. For this purpose, the chuck 1 is designed such that a bolt 11, which is displaceable relative to the receptacle 10 and has a first inclined surface 12 on the side facing the wedge rod 6, is arranged in the receptacle 10, which extends from the outer circumference of the chuck body 4 to the wedge rod 6. This first inclined surface 12 is used to terminate the toothing engagement between the tooth row 8 and the tooth gap 9 when the bolt 11 is moved out of its rest position. On the side of the wedge lever 6 facing away from the row of teeth 8, a slide 13 is arranged, which is in operative connection with the bolt 11 and has a second inclined surface 14 for re-establishing a toothed engagement between the pawl 2 and the wedge lever 6 when the bolt 11 is reset into its rest position.

The bolt 11 can be formed here as a bolt 11 which is displaceable in the receptacle in a purely translatory manner (fig. 28, 29) and has the cross-sectional configuration of a quadrilateral 15, wherein the first inclined surface 12 is then formed as a wedge surface 16.

According to an alternative embodiment, it is also possible for the bolt 11 to be formed as a cylinder with a spiral groove 18 formed on the circumferential surface, into which a guide means 19 arranged on the chuck body 4 engages, so that when the cylindrical bolt 17 is rotated about its longitudinal axis, a translational adjustment of the bolt 11 is forced in the manner of a spindle drive, due to the engagement of the guide means 19 formed as a pin 20 into the spiral groove 18.

In both embodiments of the bolt 11, a groove 21 is formed on the side of the first inclined surface 12 facing the outer circumference of the chuck body 4, into which a collar 22 associated with the slide 13 engages, wherein the groove 21 is formed as an annular groove 24 in the bolt 11 shaped as a cylinder.

Fig. 17 to 20 show an embodiment of a cylindrical bolt 17 with annular grooves 24 extending in the circumferential direction and with helical grooves 18 arranged axially staggered on the longitudinal axis of the cylindrical bolt. However, there are also possibilities shown in fig. 21 to 24, i.e. the annular groove 24 does not extend around the entire circumference of the cylinder, and the helical groove 18 extends in a region of the circumferential surface which is not provided with the annular groove 24. In this embodiment, a shortened configuration of the cylindrical bolt 17 can be achieved, as shown by a direct comparison of fig. 17 and 21.

Fig. 20 and 24 furthermore show that a wrench receptacle 23 which is suitable for torque transmission is formed in the end face of the cylindrical bolt 17 which faces the outer circumference of the chuck body 4.

A first counter surface 25, which is matched to the shape of the first inclined surface 12, and in the exemplary embodiment shown, a second counter surface 26, which is matched to the shape of the second inclined surface 14, are formed on the wedge rod 6. The distance between the first inclined surface 12 and the second inclined surface 14 is dimensioned such that the second inclined surface 14 abuts the second counter surface 26 when the first inclined surface 12 also abuts the first counter surface 25.

Fig. 31 to 33 show an embodiment in which a pin formed as a square 15 and displaceable in a purely translatory manner is realized as a one-piece design with the slide 13.

In the embodiment shown in fig. 1 to 33, the wedge rod 6 is formed in two parts, with a wedge section 27 having a chute 7 and a tooth section 28 carrying the tooth row 8, which are coupled to one another in a height-adjustable manner relative to one another, i.e. the wedge section 27 and the tooth section 28 have L-shaped coupling regions 29, which engage one another.

In fig. 34 to 37, a further embodiment is shown, which makes it possible to design the wedge lever 6 in one piece with the mating slide 13 shown in fig. 38 and 39, respectively.

In all embodiments, the configuration shown in fig. 2 can also be used, the slide 13 being acted upon by the spring element 30 in the direction of the rest position.

The operation of the quick chuck change system associated with the chuck 1 will be described below. The starting point here is the rest position of the three pins 11 shown in fig. 2, which are assigned to the respective jaws 2, so that a toothing engagement exists between the row of teeth 18 of the wedge rod 6 and the tooth gaps 9 of the jaws 2.

If a wrench is now inserted into the wrench receptacle 23 of the cylindrical bolt 17 and is rotated about its longitudinal axis, the cylindrical bolt 17 is displaced inwardly in its receptacle 10 due to the interaction of the helical groove 18 of the cylindrical bolt 17 with the guide 19, so that the first inclined surface 12 comes into contact with the first mating surface 25 of the wedge rod 6. Since the collar 22 of the slide 13 engages in the annular groove 24 of the cylindrical bolt 17, the slide 13 is displaced during the translational displacement of the cylindrical bolt 17, so that the support of the wedge rod 6, which is visible in fig. 4, is lost by the slide 13 until the second inclined surface 14 comes into contact with the second counter surface 26 and the wedge rod 6 is pressed downward due to the contact of the first inclined surface 12 with the first counter surface 25, so that the toothed engagement is terminated. In this configuration, it is possible to displace the pawl 2 in its guide groove 3, in particular to remove the pawl 2 from the guide groove 3 and replace it with another pawl 2.

If this is done, the cylinder bolt 17 can be rotated again, but this time in the opposite rotational direction, so that the cylinder bolt 17 is displaced again outward by the interaction of the spiral groove 18 with the guide 19 and is thereby moved along by the interaction of the annular collar 24 with the collar 22 of the slide 13. Here, the first ramp 12 loses contact with the first counter surface 25, while the second ramp 14 slides along the second counter surface 26 and thus presses the wedge rod 6 upwards again, so that the toothed engagement between the pawl 2 and the wedge rod 6 is restored. The displacement into the rest position is supported by the spring 30 of the loading slide 13, so that the initial position shown in fig. 4 is again reached. It should be noted that this configuration is ensured, thanks to the spring 30, in which the slide 13 keeps the wedge-shaped plate 6 engaged from below upwards with the toothing of the jaws 2.

List of reference numerals

1 chuck

2 claw

3 guide groove

4 chuck body

5 wedge rod recess

6 wedge-shaped rod

7 chute

8-tooth row

9 backlash

10 accommodating part

11 bolt

12 first inclined plane

13 sliding block

14 second inclined plane

15 quadrilateral cotter pin

16 wedge-shaped surface

17 cylindrical bolt

18 helical groove

19 guide mechanism

20 pin

21 groove

22 flange

23 spanner receiving part

24 annular groove

25 first mating surface

26 second mating surface

27 wedge-shaped section

28 teeth segment

29 coupling area

30 an elastic element.

Claims

1. Chuck for a machine tool, with a chuck body (4), a plurality of jaws (2) arranged in radial guide grooves (3) of the chuck body (4), and a wedge rod (6) driving the jaws (2), which wedge rod (6) is slidable transversely to the guide grooves (3) in a wedge rod recess (5) in the chuck body (4), which wedge rod can be engaged into corresponding tooth gaps (9) of the jaws (2) by means of a row of teeth (8) to form a helical toothing, characterized in that in a receptacle (10) extending from the outer circumferential wedge rod (6) of the chuck body (4) a pin (11) is arranged which is displaceable relative to the receptacle (10), which pin has a first bevel (12) on the side facing the wedge rod (6) for displacing the pin (11) out of its rest position, the toothing engagement between the tooth row (8) and the tooth gap (9) is ended, and on the side of the wedge-shaped lever (6) facing away from the tooth row (8) a slide (13) is arranged which is operatively connected to the pin (11), said slide having a second bevel (14) for forming a toothing engagement when the pin (11) is reset into its rest position.

2. The chuck according to claim 1, characterized in that a first counter surface (25) matched to the shape of the first bevel (12) and/or a second counter surface (26) matched to the shape of the second bevel (14) are formed on the wedge shank (6).

3. The chuck according to claim 1 or 2, characterized in that the bolt (11) is formed as a bolt (11) which can be adjusted in a purely translatory manner in the receptacle and has a second ramp (14) as a wedge surface (16).

4. Chuck according to one of claims 1 to 3, characterized in that a groove (21) is formed on the side of the first inclined surface (12) facing the outer circumference of the chuck body (4), into which groove a flange (22) assigned to the slide (13) engages.

5. The chuck according to claim 3, characterized in that the pin (11) and the slide (13) are constructed in one piece.

6. The chuck according to claim 1 or 2, characterized in that the pin (11) is shaped as a cylinder with a spiral groove (18) formed on the circumferential surface, into which a guide means (19) arranged on the chuck body (4) engages, and an annular groove (24) is formed on the side of the first inclined surface (12) facing the outer circumference of the chuck body (4), into which a collar (22) associated with the slide (13) engages.

7. The chuck according to claim 6, characterized in that the annular groove (24) does not extend around the entire circumference of the cylinder and the helical groove (18) extends in a region of the circumferential surface not provided with the annular groove (24).

8. Chuck according to claim 6 or 7, characterized in that a wrench receptacle (23) adapted to transmit torque is configured in the end face of the cylinder facing the outer circumference of the chuck body.

9. The chuck according to one of claims 2 to 8, characterized in that the spacing between the first inclined surface (12) and the second inclined surface (14) is dimensioned such that, when the first inclined surface (12) abuts the first counter surface (25), the second inclined surface (14) also abuts the second counter surface (26).

10. The chuck according to any one of claims 1 to 9, characterized in that the wedge rod (6) is formed in two pieces: a wedge section (27) having a chute (7) and a tooth section (28) carrying the row of teeth (8), the wedge section (27) and the tooth section (28) being coupled to each other in a height-adjustable manner relative to each other.

11. The chuck according to claim 10, characterized in that the wedge section (27) and the tooth section (28) have L-shaped coupling regions (29) that are fitted into one another.

12. The chuck according to any one of claims 1 to 11, characterized in that the slide (13) is acted upon by a resilient element (30) in the direction of a rest position.