DE19646124C1 - Gripping device for annular workpiece packs - Google Patents

Abstract

The gripping device has axial gripping bodies to act on both endfaces of the workpiece pack. At least one of these gripping bodies has adjustable gripping segments (6,6') which can be moved radially towards the endface (7) of the workpiece pack. The segments can be moved radially from the outside inwards or from the inside outwards relative to the endface of the workpiece pack to exert axial gripping pressure. The segments may be able to be turned by a drive, being mounted on the ends of rotating rods (4, 4').

Description

The invention relates to a device for tensioning packaged non-circular, one closed ring circumference workpieces, in particular of Piston ring blanks, by means of the two end faces of the workpiece package attacking axial clamping bodies.

For the finishing of piston ring blanks combined into a workpiece package a large number of machining operations are necessary, which are different Processing machines are carried out. The workpieces must both on Machined outside as well as on the inner circumference.

From DE 36 33 050 C1 is a lathe for simultaneous internal and External machining of piston ring assemblies known. The piston ring package is from a thrust ring axially on a counter bearing, which also represents the work spindle, pressed and thus axially clamped. For clamping workpiece packages with one other diameters must be separate, the diameter of the workpiece package adapted pressure rings are provided, which on the one hand, the tool costs and on the other hand the set-up costs are increased.

Another disadvantage of the clamping system is the fact that the recording for the Pressure ring is relatively large and heavy. The editing tools for the Internal machining must have a large axial length in order to Machining area to enter, which causes high inertial forces that are negative affect the machining accuracy.

With the known clamping device, the workpieces can at the same time The outer and inner circumference are machined, however, the workpieces must Further processing can be released from the clamping device if it is another  Processing machine must be fed, for example one Butt cutting machine that cuts a slot in the workpiece package. This Repeated clamping and clamping of the workpieces not only causes higher ones Manufacturing costs, but also affects the machining accuracy of the individual workpieces within a workpiece package.

The invention has for its object a device for clamping packaged, non-circular workpieces with a closed ring circumference create, which allows various processing options without that the workpiece package is released.

This object is achieved by the characterizing features of Claim 1 solved. Advantageous embodiments of the invention are in the Sub-claims documented.

In this way, a cantilevered tensioning device is created, which in conventional processing machines can be used. The clamped Workpiece package is due to the flying storage with much axially shorter Machining tools accessible. Workpiece packages can be made without a variety of diameter-dependent and out-of-round tools are clamped. This reduces tool costs and set-up time.

The invention is illustrated in an outline sketch using an exemplary embodiment and is explained in more detail below. Show it:

Fig. 1 cross section of a device according to the invention with attacking from the inside axial tension,

Fig. 2 partial cross-section of the device according to Fig. 1 from the outside attacking axial tension,

Fig. 3 side view according to line III-III in FIG. 1.

In Fig. 1 a tensioning device according to the invention (1) is shown for piston rings (2). The piston rings ( 2 ) are fed to the tensioning device ( 1 ) by means of a loading device (not shown). The clamping device ( 1 ) consists of a housing ( 3 ) in which axially displaceable rods ( 4 , 4 ') are arranged. A plurality of rods ( 4 ) arranged uniformly distributed over the circumference extend on the outer circumference of the piston ring package. On the inner circumference of the piston ring package, an equal number of rods ( 4 ') are arranged concentrically with the rods ( 4 ). The rods ( 4 , 4 ') are each rotatably connected to one another via a toothed belt ( 5 , 5 ') or chains (not shown). At the end of the rods ( 4 , 4 ') clamping segments ( 6 , 6 ') are arranged, which can be applied to the end face ( 7 ) of the piston ring assembly by rotating the rods ( 4 , 4 ').

For the external machining of the piston rings, the inner rods ( 4 ') are guided axially through the piston ring assembly until the clamping segments ( 6 ') reach the end face ( 7 ). By turning the rods, the clamping segments ( 6 ') are placed on the end face ( 7 ). Then a clamping pressure is introduced via the clamping segments ( 6 ') by the rods ( 4 ') being axially withdrawn via a pull rod ( 8 ). The piston rings ( 2 ) are thus clamped between a stop ( 9 ) and the clamping segments ( 6 ') to form a piston ring package. For machining the outer circumference, the clamping device is now rotated and a processing tool ( 10 ) is brought in.

For an inner circumferential machining, it is only necessary that the stop ( 9 ) is released from a locking bolt ( 11 ) so that the pull rod ( 8 ), the rods ( 4 ') and thus the entire piston ring assembly can move axially until it is in the area Clamping segments ( 6 ) arrives. The clamping segments ( 6 ) are placed on the end face ( 7 ) via the axially displaceable and rotatable rods ( 4 ). After releasing the locking bolt ( 11 ), the necessary counter pressure on the piston ring assembly is maintained by a spring. The back pressure is measured so that the piston rings ( 2 ) do not fall off.

About the rods ( 4 ) then an axial displacement of the piston ring assembly against the spring ( 12 ) until a further stop ( 9 '). In this position, the high clamping pressure required for machining the piston rings ( 2 ) can be generated again via the clamping segments ( 6 ).

The clamping segments ( 6 ') are loosened axially and turned back into the starting position. As shown in FIG. 2, the rods ( 4 ') can be axially moved out of the inner circumferential area of the piston ring package for the inner circumferential machining and free the space for the inner circumferential machining tool ( 13 ). The clamping force is now applied exclusively by the outer clamping segments ( 6 ).

As can be seen from Fig. 3, the clamping segments ( 6 , 6 ') are arranged concentrically, but offset from one another in the circumferential direction. For the machining of the piston ring joint ( 14 ), a certain free space for the machining tool (not shown) is created, in which a clamping segment ( 6 '') is not driven directly via a gear ( 15 ) as in the other clamping segments ( 6 , 6 ') is, but via an intermediate gear ( 15 '). In this way, a relatively large free space is created, into which a processing tool can engage in order to cut open the piston rings ( 2 ).

Claims (7)

1. Device for clamping packaged non-circular workpieces having a closed ring circumference, in particular piston ring blanks, by means of axial clamping bodies acting on the two end faces of the workpiece package, characterized in that at least one axial clamping body in the region of the end face ( 7 ) of the workpiece package radially in the direction of the end face ( 7 ) of the workpiece package has adjustable clamping segments ( 6 , 6 ') which can be fed radially from the outside in and / or from the inside to the outside of the end face ( 7 ) of the workpiece package in order to initiate an axial clamping pressure. 2. Device according to claim 1, characterized in that the clamping segments ( 6 , 6 ') at the end region of rotatably driven rods ( 4 , 4 ') are arranged. 3. Apparatus according to claim 2, characterized in that the rods ( 4 , 4 ') extend on the outer and / or inner circumference of the workpiece package and are axially displaceable. 4. The device according to claim 2, characterized in that the clamping segments ( 6 ) of the rods arranged on the outer circumference ( 4 ) with respect to the clamping segments ( 6 ') are arranged offset on the inner circumference in the circumferential direction. 5. Device according to one of claims 1 to 4, characterized in that the outer and / or inner clamping segments ( 6 , 6 ') can be delivered synchronously against the end face ( 7 ) of the workpiece package. 6. Device according to one of claims 1 to 5, characterized in that at least two external and two internal clamping segments ( 6 , 6 ') are arranged over the workpiece circumference. 7. Device according to one of claims 2 to 6, characterized in that the arranged on the outer or inner circumference rods ( 4 , 4 ') via a toothed belt ( 5 , 5 ') are interconnected.