JPH0569208A - Power operation type chuck - Google Patents

Abstract

PURPOSE: To compensate for the loss of a clamping force caused by the centrifugal force of a foundation jaw and/or a clamping jaw and to prevent the clamping force from increasing during the stop of a chuck. CONSTITUTION: A turning lever 36 is rotatably supported within a drive jaw 21, advantageously in a recess 37 bored in the drive jaw 21. A foundation jaw 15 or a clamping jaw 16 is drivingly connected to the drive jaw 21 in such a way as to be radially movable by means of the turning lever 36 so that during outer clamping, the foundation jaw 15 or the clamping jaw 16 can be moved radially inwards by means of a compensating weight 35, and so that during inner clamping, the compensating weight 35 is locked without a play, the foundation jaw 15 or the clamping jaw 16 can be moved in a radial direction by means of the turning lever 36.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention has an axially movable piston arranged in a chuck body.
Via a wedge transmission, it is drivingly connected to a drive jaw which is inserted in a groove drilled in the chuck body so as to be oriented in a radial direction, and one base jaw or one clamping jaw can be operated by the drive jaw. Yes, a compensating weight is attached to each of the basic jaws and the tightening jaws, and the compensating weight is movably supported by a turning lever of two arms.
The present invention relates to a power operated chuck for a rotary machine, which is drivingly connected to an attached base jaw or tightening jaw.

[0002]

2. Description of the Related Art In a chuck for a rotary machine of this kind, a centrifugal force generated by a tightening jaw reduces a tightening force when the chuck body is rotated, and therefore a measure is taken to compensate for this. Such a chuck is a German patent No. 2
It is known from Japanese Patent No. 749624. In the case of this known configuration, the turning lever is rotatably supported substantially at the center of the chuck body, and one end of the turning lever is pivotally attached to the drive jaw.
The other end is pivotally attached to the compensating weight. The turning lever is therefore supported directly in the chuck body, so that the centrifugal forces of the clamping jaws, drive jaws and compensating weight that occur at high rpm are all absorbed by the chuck body. This reduces the load on the wedge transmission and reduces the frictional force of the piston drivingly connected to the drive jaws on the inner surface of the bore that guides and deforms the piston. Therefore, the piston is additionally moved by the force that constantly acts on it beyond the operating position corresponding to the predetermined clamping force. However, since the piston keeps the occupied position even after the rotation of the chuck is completed, the tightening jaws have more force than the tightening force originally introduced to act on the work piece according to the position change of the wedge transmission. Is also very high and an undesired tightening force acts. This increase in tightening force may deform and damage the work piece.

A further disadvantage of this known chuck is that it cannot be used to machine ring-shaped workpieces. That is, when a ring-shaped workpiece is clamped and fixed, the clamping jaws act on the workpiece from the inside to the outside, and if the size of the individual movable parts is unfavorably selected, the centrifugal force generated by the clamping jaws causes the compensating weight to move. In addition to being not compensated for, the clamping force introduced may be reduced to a considerable extent, so that a secure clamping fixation is not provided and the workpiece is disengaged during operation. Further, since the turning lever is supported almost at the center of the chuck body, the transmission ratio is not preferable, and it can be changed only in a narrow range. Therefore, the size of the compensating weight should be selected accordingly. I won't. Therefore, this known chuck does not provide a satisfactory operating mode and versatile application.

[0004]

The object of the present invention is to construct a power-operated chuck of the kind mentioned at the outset in the following way: the clamping force produced by the centrifugal force of the basic jaw and / or the clamping jaw. Not only is the loss reliably compensated during operation, but the clamping force is not increased when the chuck is stopped. Another object of the present invention is to ensure that the centrifugal force generated by the base jaw and / or the tightening jaw and the compensating weight is supported so as not to expand the chuck body, and the transmission ratio between the lever arms of the turning levers. Of the compensating weight and, as a result, the size of the compensating weight and the length of its travel path can be chosen small, nevertheless ensuring that centrifugal forces occurring at high rpm are compensated. , Allowing the clamping jaws to move over a wide range of movement without changing the kinematic properties of the clamping jaws, simplifying the construction required for this, economical in the manufacture of this type of power operated chuck Is to

[0005]

According to the present invention, in order to solve the above-mentioned problems, a turning lever is rotatably supported in a drive jaw, preferably in a recess formed in the drive jaw. Such that the base jaws or the clamping jaws can be moved radially inward by the compensating weight during the outer clamping and the compensating weight is locked without play during the inner clamping. The tightening jaw is drivingly connected to the drive jaw so as to be movable in the radial direction by a turning lever.

It is expedient if the basic jaws or the clamping jaws are connected with the drive jaws in such a way that they can be displaced in a radial direction by a predetermined movement distance limited by a stop.

Stops for limiting the radial range of movement of the base jaws or the clamping jaws are formed by axially projecting add-on parts integrally formed with the drive jaws or the foundation jaws or the clamping jaws, respectively. A concise design results when the extension part engages in a recess provided in the basic jaw or the clamping jaw or the drive jaw with radial clearance.

However, according to another embodiment of the present invention, one end of each turning lever is rotatably supported in a free space provided in the base jaw or the tightening jaw, and each turning lever includes a bending lever. It can also be supported by a drive jaw via. In this case, each bending lever is formed by a pressure member mounted on said one end of the deflection lever which is pivotally supported, said pressure member being pivotally attached to the deflection lever and pivotable in the drive jaws. Supported by.

In this case, one of the stop portions for limiting the radial movement range of the base jaw or the tightening jaw is a joint portion formed integrally with the drive jaw and projecting in the axial direction, and the bending lever is Formed by an extension that is radially clearance-engaged with a free space provided in the base jaw or the clamping jaws for receiving, and another stop for cooperating with the base jaws or the clamping jaws. It is formed by a supporting surface provided on the turning lever. Furthermore, the radially inner surface of the recess of the drive jaw, which accommodates the deflection lever, in the radial direction is configured as a flat stop surface, in the region where the deflection lever cooperates with said stop surface (lever end). It is composed of polygons.

According to another embodiment, two stops for limiting the radial displacement of the base jaws or the clamping jaws are formed by stop surfaces formed on the drive jaws and cooperating with the deflection lever. Can be In this case, the recess of the drive jaw, which accommodates the turning lever, is configured as a flat stop surface on the compensating weight side, and the turning lever is polygonal in the area (lever end) attached to said stop surface. It is configured.

Furthermore, the deflection lever is supported in the recess of the drive jaw by means of a support surface which is formed integrally therewith and is configured in the shape of a ball or barrel, and the end of the deflection lever is in the base jaw or the clamping jaw, And is preferably rotatably supported in the compensation weight.

The drive jaws are guided in a groove which is drilled in the chuck body and is T-shaped in cross-section and is radially displaceable axially with respect to the basic jaws or the clamping jaws. be able to. However, it is also possible for the drive jaws to be guided radially displaceably in a groove which is drilled in the chuck body and which is rectangular in cross section and which is axially supported by the base jaws or the clamping jaws. ..

Further, the compensating weight is a hermetically-sealed cover having a concave portion directed in the radial direction,
It can also be movably guided in a sealing cover fixed to the chuck body on the side facing the base jaws or the clamping jaws.

[0014]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

As shown in FIGS. 1, 5, and 6, reference numeral 1,
The power-operated chuck with 1'and 1 '' is used to clamp and fix the workpiece 10 or 10 'on the rotating machine, and is used for the chuck body 11 and the radial groove provided in the chuck body 11. A base jaw 15 movably guided in 14 and fixed to a clamping jaw 16 acting on the workpiece 10 or 10 ′, and a drive jaw 21 which is likewise movably inserted in a groove 22. is doing.
The drive jaw 21 is drivingly connected to the axially movable piston 19 and the base jaw 15. On the side of the chuck body 11 facing the basic jaw 15, the screw 1
The cover 12 is fixed by 3. A compensation weight 35 is provided in the radial recess 34 of the cover 12. The compensating weight 35 is connected to the base jaw 35 via a two-arm turning lever 36 that penetrates a recess 39 formed in the chuck body 11. The piston 19 is movably inserted into a hole 18 in the center of the chuck body 11, and is connected to a servo device (not shown) via a pull rod 20. The servo device allows the piston 19 to move axially in the bore 18 in a coordinated manner. The groove 14 of the chuck body 11, which accommodates the basic jaw 15, is closed inside by a bush 17.

In order to convert the axial adjustment movement of the piston 19 into the radial adjustment movement of the drive jaw 21, the drive jaw 21 is provided on both sides with wedge hooks 23 extending in an axially inclined manner. There is. The wedge hook 23 has wedge surfaces 24 and 25. And piston 19
A wedge groove 26, which is attached to the wedge hook 23, is formed therein. Wedge surfaces 27 and 2 due to wedge groove 26
7'is formed. When the piston 19 is displaced axially to the left, the wedge surface 27 of the piston 19 acts on the wedge surface 24 of the wedge hook 23, so that the drive jaw 21 is displaced radially inward and clamps against the workpiece 10. A clamping force is applied via the jaws 16. On the other hand, when the piston 19 is axially displaced to the right, the wedge surface 27 ′ of the piston 19 cooperates with the wedge surface 25 of the wedge hook 23 to drive the drive jaw 21.
Moves outward and the workpiece 10 'is clamped.

Further, the drive jaw 21 includes a basic jaw 1
One additional portion 28 is integrally formed on each of the end faces on the fifth side. The extension portion 28 engages with the recess 31 formed in the base jaw 15 with a play in the radial direction.
The radial surfaces of the additional portion 28 and the recess 31 are the stop surfaces 2
9 and 30 or 32 and 33. When the workpiece 10 is clamped and fixed, the base jaws 15 can be moved radially inward via this stop surface, and when clamping and fixing the workpiece 10 ′, the base jaws 15 are likewise moved through this stop surface. Can be displaced outward in the radial direction.

In the power operated chuck 1, the two-arm turning lever 36 is rotatably supported in the drive jaw 21. To achieve this, the drive jaw 21 has a recess 3
7 is formed and the deflection lever 36 comprises a support surface 38 which is configured in the shape of a ball or barrel. As a result, a limited rotational movement is possible. One end of the turning lever 36 engages with the recess 40 formed in the compensating weight 35, and the other end engages with the recess 41 provided in the basic jaw 15. In the region of the recesses 40 and 41, the deflection lever 36 is provided with a bearing surface 42 or 43 which is likewise shaped like a ball or barrel, and the end faces 44 and 45 of the deflection lever 36 are also shaped like balls. As a result, pushing at the inclined position is prevented.

As can be seen in FIG. 3, the groove 22 containing the drive jaw 21 has a T-shaped cross section. The drive jaw 21 is therefore guided in the groove 22 and its end face is not in contact with the basic jaw 15. Therefore drive jaw 2
Friction forces between 1 and the basic jaw 15 are avoided.

A turning lever 36 is drivingly connected to the driving jaw 21 so that the basic jaw 15 can be moved in a radial direction by a predetermined distance. As shown in FIG. 1, when the drive jaws 21 are pulled radially inward by the piston 19 in order to clamp and fix the workpiece 10, the stop surface 29 of the add-on 28 is fixed by the stop surface 32 of the basic jaw 15.
And the basic jaw 15 is carried. When the workpiece 10 is tightened and the chuck 1 is rotated, the basic jaw 15
A centrifugal force is generated by and the tightening jaw 16. This centrifugal force counteracts the clamping force acting on the workpiece 10 and thus reduces this clamping force.

However, at the same time, a force is generated in the radial direction by the compensating weight 35, and the compensating weight 35 is transferred through the turning lever 36.
Since a drive connection is made between the base jaw 15 and the base jaw 15, the centrifugal force of the compensating weight 35 is replaced according to the lever ratio and transmitted to the base jaw 15, so that the centrifugal force of the base jaw 15 is reacted.

This allows the base jaws 15 to move further inward in the radial direction in order to compensate for the elastic deformation of the individual parts. However, the stop surface 33 has the extension 28.
Until the stop surface 30 on the outer side of is contacted. All the centrifugal forces of the movable parts are first absorbed by the drive jaws 21 and transferred to the piston 19 via the wedge hook 23, so that the piston 19 is pressed firmly against the inner surface 46 of the hole 18. Therefore, after the chuck 1 is stopped, the tightening force acting on the workpiece 10 is increased and the additional displacement of the piston 19 in the axial direction, which would be inconvenient, is reliably prevented.

On the other hand, when the ring-shaped workpiece 10 'is clamped between the clamping jaws 16, the drive jaws 21 are displaced outward by the axial displacement of the piston 19 to the right. In this case, the extension 28
The stop surface 30 of the above acts on the stop surface 33 of the basic jaw 15. By the way, when the chuck body 11 rotates in the case of such outer tightening, the centrifugal force generated by the compensating weight 35 is transmitted to the basic jaw 15 via the turning lever 36, but the stop surface 33 of the basic jaw 15 is fixed to the driving jaw 21. By contacting the extension 28, the base jaws 15 move radially inward, thus preventing a reduction in the clamping force acting on the workpiece 10 '. In addition, centrifugal force is applied to the driving jaw 21.
Since it is sufficiently absorbed and supported by the piston 19, the tightening force after stopping the chuck body 11 does not increase undesirably.

The chuck 1'shown in FIG. 5 is also shown in FIGS.
The chuck 1 has the same structure as that of the chuck 1 shown in FIG. However, one end of the turning lever 36 ′ is rotatably supported in a free space 31 ′ formed in the basic jaw 15 and, via the bending lever 51, the driving jaw 2 ′.
It is supported by 1 '. The free space 31 ′ basically corresponds to the recess 31 of the chuck 1. Bending lever 51
Is the pressure member 5 acting on the end 55 of the turning lever 36 '.
It is formed by 2. Each pressure member 52 is rotatably engaged with a support surface 53 formed on the extension 28 'of the drive jaw 21', and another support surface 54.
It is pivotally attached to the turning lever 36 'via. For this reason, the turning lever 36 ′ has a corresponding support surface 57.
have. The turning lever 36 ′ is rotatably held by the support surface 58 formed on the basic jaw 15 by the support surface 56 arranged so as to be substantially opposite to the support surface 57.

In the power-operated chuck 1 ', the base jaw 15 is moved toward the workpiece 10 via the pressure member 52 of the bending lever 51 during the external tightening. The polygonal end 55 of the turning lever 36 ′ is arranged on the drive jaw 21 ′ so that the forces introduced during the inward displacement movement of the drive jaw 21 ′ can be transmitted to the basic jaw 15. Contact the stop surface 59. The compensation of the centrifugal force generated by the base jaw 15 and the tightening jaw 16 can be performed by the compensating weight 35. That is, the basic jaw 15 is provided with a turning lever 36 'and a bending leg 51 attached to the turning lever 36', so that the stopping surface 30 'of the extension 28' is fixed.
It is possible to move further inward until the stop surface 33 'of the base jaw 15 comes into contact.

On the other hand, when tightening the inside,
The drive jaw 21 ′, the deflection lever 36 ′ penetrating the recess 37 ′ and the compensating weight 35 move outwards until the stop surface 30 ′ of the extension 28 ′ comes into contact with the stop surface 33 ′ of the basic jaw 15. Moving. In this case, the support surface 58 of the turning lever 36 'is lifted from the support surface 58 by the play of the stop surfaces 30' and 33 '. When the compensating weight 35 moves outward during rotation of the chuck body 11, the turning lever 36 'pivots, but only moves until it contacts the stop surface 60 formed on the drive jaw 21'. In this case, the turning lever 36 ′ or the bending lever 51 is not
It is held between 58 and 58 without play. On the other hand, compensating weight 3
The centrifugal force of 5 is not transmitted to the base jaw 15 by the contact of the turning lever 36 'with the stop surface 60 of the drive jaw 21', so that the chuck 1'is also suitable for internal clamping.

Power operated chuck 1 '' shown in FIG.
The turning lever 36 ″ is rotatably supported in the recess 37 ″ of the drive jaw 21 ″ by the barrel-shaped support surface 38 ″ integrally formed with the turning lever 36 ″. In this arrangement, the inner and outer surfaces of the recess 37 '' in the radial direction limit the stop surfaces 61 and 6 respectively to limit the radial relative movement of the base jaw 15 with respect to the drive jaw 21 ''.
It is formed as 2. The stop surfaces 61 and 62 cooperate with the polygonal end 55 ′ of the turning lever 36 ″ that passes through the recess 37 ″.

When the outer jaw is tightened, that is, when the drive jaw 21 '' is displaced inward, the base jaw 15 is moved.
Are carried by the turning lever 36 ''. In this case, the end 55 ″ of the turning lever 36 ″ is supported by the stop surface 61 of the recess 37 ″. The compensating weight 35 compensates the centrifugal force generated by the base jaw 15 and the tightening jaw 16, so that the compensating weight 35 causes the turning lever 3 to move.
The 6 ″ can be pivoted until it contacts the stop surface 62, so that the base jaw 15 can be displaced further inwards.

In the case of tightening the inside, first, the basic jaw 1
The drive jaws 21 '' and the deflection lever 36 '' cooperating with the support surface 61 carry the 5 outwards until it contacts the workpiece. However, since the turning lever 36 ″ is rotatably supported in the driving jaw 21 ″ by the barrel-shaped supporting surface 38 ″, when the driving jaw 21 ″ is further displaced, the turning lever 36 ″ is moved. '' Is the stop surface 62
Tilt until it touches. In this operating position the turning lever 3
The 6 ″ acts as a robust entrainer which causes the basic jaws 15 or the clamping jaws 16 connected thereto to be pressed against the workpiece to be clamped.

The centrifugal force generated by the compensating weight 35 is absorbed by the drive jaw 21 '' by the contact of the turning lever 36 '' with the stop surface 62, thus preventing a reduction in the clamping force.

As can be seen in FIG. 7, in the chuck 1 ″, the groove 22 ″ that houses the drive jaw 21 ″ and is formed in the chuck body 11 has a rectangular cross section. However, the drive jaw 21 ″ is positively supported by the basic jaw 15 in the groove 22 ′.

Next, the advantageous configurations of the present invention will be listed.

(1) The base jaw (15) or the tightening jaw (16) is provided with a stop (29, 30; 30 '; 5).
6; 61, 62), which is connected to the drive jaw (21) so as to be movable in a radial direction by a predetermined movement distance limited by the power-operated chuck.

(2) Stops (29, 30) for limiting the radial movement distance of the base jaw (15) or the tightening jaw (16) are respectively provided with driving jaws (2).
1) or a base jaw (15) or a clamping jaw (16), formed by an axially projecting extension (28), said extension (28).
But base jaws (15) or tightening jaws (16)
Or a recess (31) drilled in the drive jaw (21)
The power-operated chuck according to item 1 above, wherein the power-operated chuck is engaged with a radial clearance.

(3) One end (5) of each turning lever (36 ')
5) is a basic jaw (15) or a clamping jaw (1
6) is rotatably supported in a free space (31 ') formed in 6) and each turning lever (36') is a bending lever (51).
A power operated chuck characterized in that it is supported by a drive jaw (21 ') via the.

(4) Each bending lever (51) has one end (55) at which the turning lever (36 ') is rotatably supported.
Formed by a pressure member (52) attached to
Power according to claim 3, characterized in that the pressure member (52) is pivotally attached to the deflection lever (36 ') and is rotatably supported in the drive jaw (21'). Operable chuck.

(5) One of the stoppers (30 ') for limiting the radial movement range of the base jaw (15) or the tightening jaw (16) is integrally formed with the drive jaw (21') to form a shaft. Extension (28 ') protruding in the direction
Which is in free radial engagement with the free space (31 ') provided in the base jaw (15) or the clamping jaw (16) to accommodate the bending lever (51). (28 '), the other stop is a base jaw (15) or a clamping jaw (16).
Power-operated chuck according to item 3 or 4 above, characterized in that it is formed by a supporting surface (56) provided on the turning lever (36 ') so as to cooperate therewith.

(6) The inner surface of the drive jaw (21 ') in the radial direction of the recess (37') accommodating the turning lever (36 ') is formed as a flat stop surface (59). The power-operated actuation system according to claim 5, characterized in that the turning lever (36 ') is polygonal in the area (lever end 55) cooperating with the stop surface (59). Chuck.

(7) Two stops for limiting the radial movement range of the base jaw (15) or the tightening jaw (16) are formed in the drive jaw (21 ''), and the turning lever (36 ''). ) Cooperating with stop surface (61, 62)
A power-operated chuck, characterized in that it is formed by.

(8) The recess (37 '') of the drive jaw (21 '') which houses the turning lever (36 '') is
Configured as flat stop surfaces (61, 62) on the compensating weight (35) side, the turning lever (36 '') is
7, 62) characterized in that the area (lever end 55) attached to (1, 62) is polygonal.
A power operation type chuck according to the item.

(9) The turning lever (36; 36 '') is
A drive jaw (21; 2) is formed by a support surface (38; 38 ″) integrally formed therewith and configured as a ball or barrel.
1 '') is supported in a recess (37; 37 '') and the end of the turning lever (36; 36 '') is attached to the base jaw (1;
5) or in the clamping jaws (16) and in a compensating weight (35) rotatably supported, according to any one of the above items 1 to 8. Power operated chuck.

(10) The drive jaws (21) are provided in the chuck body (11) in the groove (22) having a T-shaped cross section, and the base jaws (15) or the tightening jaws (16) are provided. The power-operated chuck according to any one of the above items 1 to 9, which is guided so as to be movable in the radial direction with a space in the axial direction.

(11) A drive jaw (21 '') is guided to be movable in a radial direction in a groove (22 '') formed in the chuck body (11) and having a rectangular cross section. The power-operated chuck according to any one of the above items 1 to 9, characterized in that it is supported in the axial direction by a basic jaw (15) or a clamping jaw (16).

(12) Sealing cover (12) in which the compensating weight (35) is provided with a recess (34) which is oriented in the radial direction.
And the basic jaw (1) of the chuck body (11)
5) or the side opposite to the tightening jaws (16) is movably guided in a sealing cover (12) fixed to the chuck body (11), the above-mentioned items 1 to 11. The power-operated chuck according to any one of items 1 to 7.

[0045]

In the power operated chuck according to the present invention,
A turning lever is rotatably supported in the drive jaws, and the base jaw and / or the clamping jaws are connected with the driving jaws with radial clearance through the turning lever so that the clamping force is exerted on the workpiece from the outside. In addition to compensating the centrifugal force generated by the tightening jaws, it is possible to prevent the influence of the compensating weight during the inner tightening. That is, when tightening inward, the compensating weight is locked by the stopper without any play, so that the centrifugal force of the compensating weight is supported by the drive jaw via the turning lever.
Therefore, the tightening force of the tightening jaws is not affected by the reaction and the tightening force does not decrease. Therefore, a versatile application of the chuck is guaranteed.

A particularly important advantage of the invention, on the other hand, is that the clamping force is not increased by the additional unwanted movement of the piston when the chuck is stopped after the end of the machining process. The centrifugal forces of the base and / or clamping jaws and of the compensating weight are not directly supported in the chuck body, but are first absorbed by the drive jaws and then transmitted from the drive jaws to the piston via the wedge transmission. Therefore, the chuck body is hardly elastically deformed. Rather, when the chuck body rotates, the piston is pressed against the inner surface of the hole accommodating the piston due to the increased frictional force in a wide range of the peripheral surface, and the load of the wedge transmission is not reduced at this time. The piston does not move additionally.

Since the turning lever is directly rotatably supported in the drive jaws or the basic jaws and / or the clamping jaws, the transmission ratio can be selected to be very large, and thus the transmission ratio can be set. Highly preferred. Therefore, the compensating weight provided on the side of the chuck body facing the basic jaw and / or the tightening jaw is arranged with a large distance from the supporting position of the turning lever, and therefore the weight of the compensating weight can be reduced. it can. Also, since the turning lever is supported by the drive jaws, the kinematics of the displaceable individual parts remain unchanged over the entire range of travel of the drive jaws. That is, the supporting position of the turning lever is also displaced in the radial direction, so that the turning lever does not occupy an extremely inclined position, and the unique moving distance of the compensating weight is short. Thus, the power-operated chuck constructed according to the present invention is not only extremely versatile, but also economically producible, has a long service life, and is highly stable in operation.

[Brief description of drawings]

1 is an axial cross-sectional view of a power operated chuck according to the invention with a turning lever pivotally supported in a drive jaw for drivingly connecting individual radially displaceable parts.

2 shows the chuck of FIG. 1 in another operating position.

FIG. 3 is a sectional view taken along line II-II in FIG.

FIG. 4 is a cross section taken along line IV-IV in FIG. 1 and line IV′-
FIG. 4 is a cross-sectional view in a direction perpendicular to the axial direction, which is a combination of the cross section according to IV ′.

5 is an axial sectional view of a modified example of the chuck of FIG.

6 is an axial cross-sectional view of another modified example of the chuck of FIG.

7 is a cross-sectional view taken along the line VII-VII in FIG.

[Explanation of symbols]

 15, 16 Tightening jaws 21, 21 ', 21 "Driving jaws 35 Compensating weights 36, 36', 36" Turning levers 37, 37 ', 37 "Recesses

Claims (1)

[Claims] 1. A piston movable in the axial direction is arranged in the chuck body, and the piston is inserted through a wedge transmission device so as to be directed in a groove formed in the chuck body in a radial direction. A driving jaw is drivingly connected, and one base jaw or one tightening jaw can be operated by the driving jaw, and a compensation weight is attached to each of the base jaw and the tightening jaw, and the compensation weight is rotatably supported. In a power-operated chuck for a rotary machine, which is drivingly connected to an attached basic jaw or tightening jaw via a double-armed turning lever, the turning lever (36; 36 ';36'') is driven. Recesses (3) bored in the jaws (21; 21 ';21''), preferably in the drive jaws (21; 21'; 21 '').
7; 37 ';37'') pivotably supported, the base jaws (15) or clamping jaws (16) being able to move radially inward by means of a compensating weight (35) during external clamping And the base jaws (15) or clamping jaws (16) are diverting levers (36; 36 ';36') so that the compensating weight (35) is locked without clearance during internal clamping. Power-operated chuck for a rotary machine, characterized in that it is drivingly connected to a drive jaw (21; 21 ';21'') so as to be movable in the radial direction by means of a').