EP1262280B1 - Apparatus for deep rolling recesses and radii of journal bearings of crankshafts - Google Patents

Abstract

The rollers (8) may be inclined at an angle of 35 degrees. They are pressed into the corners of a broad bearing groove by a pair of inclined guide surfaces (9) on the deforming tool (7) to form small grooves (4). There are tool housing members (6) on either side of the tool, which consists of a roller. A distance or position sensor (14) is placed between a central rib (13) on the tool and the floor of the broad bearing groove. The rollers induce stretching forces (10) in the metal round the small grooves.

Description

The invention relates to a device for deep rolling from punctures and radii to crankshafts after the Features of the preamble of the main claim.

The deep rolling of crankshafts is done with the help of Fixed rollers, with a predetermined force in the Grooves and radii are pressed, which the bearings each side of a crankshaft limit. One Method, a machine or tools for deep rolling the radii and punctures of crankshafts are for example, known from EP 0 683 012 A1 and from EP 0 661 137 B1 and EP 0 299 111 B1. Both known method is using the known Rotate machines with the help of the deep rolling tool mounted deep rolling rollers the material of the crankshafts Plasticized up to about 1 mm depth. It builds up tangential to the rolling radius of the deep rolling rollers Residual compressive stresses that occur at the bending load of Crankshaft in operation, the formation of cracks on the critical points of transition from journal to Reduce the cheek of the crankshaft and thus the Significantly increase fatigue strength of a crankshaft. The Goodness of a Festwalzung is for the life of a Crankshaft crucial. With higher Torques and greater engine power, in particular With the spread of diesel engines, the Demands on the crankshafts ever higher. As a result this has led the industry to do that Deep rolling of crankshafts increasingly critical and with to operate with ever higher accuracy. It is known So far, the deep rolling with a predetermined Perform deep rolling force. Keeping the However, deep rolling force alone is not able to Scattering of the strength of the material of the crankshaft or by pre-machining the crankshaft, in particular the machining and, where appropriate hardening, introduced into the crankshaft Compensate for inaccuracies. Error of pre-processing at festzuwalzenden punctures or radii at one Crankshaft are made by the known method, where a specified firm rolling force is maintained, not uncovered.

Furthermore, from DE 195 11 882 A1 a method for Solidification of workpiece surfaces has become known. The well-known method is also on the Crankshaft machining applicable. Here is the Workpiece surface during the solidification process metrologically recorded and out of the measurement results Controlled variables for setting / changing of Derived tool parameters. In particular, the Penetration depth of the deforming tool in the Workpiece surface detected. One with one corresponding pressing force acting fixed roller penetrates into the material and thus generates depending on Flow behavior of the workpiece material Aufwürfe on both sides of the penetrating deep rolling roller. The actual penetration depth of the deep rolling roller results then from the difference of the complaints. It can the Surface contour metrologically in itself on varied Way are detected mechanically, for example, pneumatic, hydraulic, acoustic, electromagnetic, electrocapacitive or electronically by means of appropriate acting feeler.

A disadvantage of the known method is the indirect Detecting the penetration depth over the Aufwürfe on both sides the penetrating deep rolling roller. Such complaints are sometimes not available or so little pronounced that they are hardly detected metrologically can. This is especially the case with the Throwing up the transitions to both sides of Engraving in crankshafts, yes in each case different levels lie. There is enough, so has the Experience shown the accuracy with which the pains can not be measured to reliable Statements about the penetration depth of the deep rolling roller in the To make crankshaft. It is much cheaper instead to directly follow the path of the deep rolling roll it in radial, be it in the axial direction of movement in Reference to the crankshaft or in both Movement directions at the same time.

In addition, it can be used in industrial practice happen that individual. Deep rolling rolls of a machine compared to the other fixed rollers a shorter one Have service life and fail prematurely. With the hitherto known means is such a premature Failure of the deep rolling tool difficult or impossible not to be discovered. The industry has therefore so far thus, randomly manage the rolled radii or punctures of crankshafts with the help of measuring tongs to be controlled by hand.

From the above-described difficulties and Disadvantages results in the task for the invention, the Deep rolling of the radii and punctures of crankshafts continue to improve, in particular to ensure a consistent Production result and possible errors, resulting from the previous processing of the Workpiece have crept into the process with to discover and eliminate in time. It should the improvement without any extra effort and up be economically feasible manner. Especially should already existing facilities, such as Crankshaft deep rolling machines and crankshaft deep rolling tools as well as known measuring and Control devices, without significant changes to Performing the deep rolling be used.

To solve the inventive task is a Device proposed with the features of claim 1, with which one the penetration depth in the radial direction of the fixed rollers of a Solid rolling tool continuously measures and the size of the Deep rolling force as a function of the measured Penetration depth regulates that in the course of Deep rolling operation on the punctures or radii of a Bearing point after the deep rolling a plastic Deformation is obtained, which is a predetermined Einwalztiefe corresponds.

Similarly, errors that occur during the Pre-processing, be it by machining, be it by hardening, introduced into the crankshaft were revealed. This is a measuring tool used, which is constructed identically as a Rolling tool. Be under a low application force before the actual start of the deep rolling operation Measuring rollers introduced into the grooves of the bearings. The taking place during penetration axial spreading of Measuring rollers are recorded and used as a measure of the quality of the Preprocessing determined. Serve with sensors that the axial distance of individual measuring rollers to the adjacent ones Capture crankshaft crankshaft.

The known method, the punctures and radii of Crankshafts with a predetermined rolling depth to roll is now improved so that one depending on the state of the To be rolled radii or grooves of the crankshaft achieves a specific rolling depth, and to achieve this Einwalztiefe the Festwalzkraft accordingly changes.

The device may include such a method with a single deep rolling roller of a deep rolling tool but it can also do the resulting Penetration depth of both deep rolling rollers, which a Deep rolling tool usually has to be measured. In addition, the resulting axial displacement of the Measuring rollers of a measuring tool are detected. To measure the penetration depth of the deep rolling rollers or the displacement the measuring rollers of a measuring tool in the axial direction Several facilities are suitable, their special ones Selection in the area of measures of the relevant expert lies.

The penetration depths measured by means of sensors Hard rollers of a deep rolling tool or Displacements of the measuring rollers of a measuring tool fed to a computer, stored in the computer, in Calculated variables and then the Fixed rolling force regulated. Usually you go this way before that you have the crankshaft before the actual Deep rolling initially with a low and constant Mooring force rolls and after deep rolling under the Deep rolling force forms the difference of the measured values, the arising from the penetration depths under the application force and the Firm rolling force results and then on the basis of a corresponding calculated computational size determines the penetration depth. A such a computational variable is advantageously suitable for Error that is in the pre-machining of the crankshaft it through machining, be it through hardening or due to damage to the deep rolling rollers themselves, occur too determine.

Except at the first two outer ends of the two scissors-like arms, which are each the parts of a Can carry rolling mill tool, sensors can also in different measuring levels along the arms of the device be arranged. In addition to the possibility of penetration the deep rolling rollers in the crankshaft in radial Direction is determined, provided that that the two measuring rollers one like a deep rolling tool designed measuring tool within the Measuring roll tool at an angle of approximately 35 ° are inclined to the possibility of intrusion of the Measuring rollers resulting axial spread of the measuring rollers to be determined with the help of sensors.

Inductive sensors, in turn, are suitable as sensors. Triangulation probe with optical function, digital Distance measuring probes, potentiometers or ultrasonic sensors. The selection of the most suitable sensors meets the relevant expert. It is intended that also triangulation buttons, which with laser beams work, can be used. Both digital Distance sensors as well as capacitive potentiometers can be designed as facilities, which after the Measure eddy current method. It is significant that the respective sensors with a measuring range of about 1 mm have at least 10-fold resolution, with the Measured size of the rolling depth between 0.1 and 0.9 mm lies.

• Fig. 1, ein Festwalzwerkzeug in der Vorderansicht,
• Fig. 2, die Anordnung eines Festwalzwerkzeugs innerhalb eines einzelnen Festwalzgerätes,
• Fig. 3, das Schema der Messrichtungen
• Fig. 4, das Messen einer axialen Verlagerung von Messrollen eines Messwerkzeugs,
• Fig. 5, die Messanordnung der Fig. 2 in der Seitenansicht,
• Fig. 6, unterschiedliche Messebenen entlang eines Gerätearmes,
• Fig. 7, das Schema einer Befestigung von Sensoren,
• Fig. 8, eine einschwenkbare Messvorrichtung.
• Fig. 9, eine Einrichtung zur Messung von unterschiedlichen Einwalztiefen
• Fig. 10, ein Festwalzgerät mit einem Weggeber.

The invention will be described in more detail below with reference to some embodiments. In each case in a highly simplified, not to scale and predominantly schematic representation of the show

• 1, a deep rolling tool in the front view,
• 2, the arrangement of a deep rolling tool within a single deep rolling device,
• Fig. 3, the scheme of the measuring directions
• 4, measuring an axial displacement of measuring rollers of a measuring tool,
• 5, the measuring arrangement of Fig. 2 in side view,
• 6, different measurement levels along a device arm,
• 7, the scheme of attachment of sensors,
• Fig. 8, a pivotable measuring device.
• Fig. 9, a device for measuring different Einwalztiefen
• Fig. 10, a deep rolling device with a displacement sensor.

In the following representations are those parts, which directly affect the crankshaft, respectively specially marked by hatching. Controls are represented by broken lines.

Fig. 1 shows the course of the deep rolling a Crankshaft 1. Crankshaft 1 has a bearing 2, for example, for a main or connecting rod bearing. In Direction of the longitudinal axis of the crankshaft 1, for example represented by the parallel to the longitudinal axis dot-dash line 3, the bearing 2 is the side each limited by punctures 4. As in FIG. 1 clearly recognizable, the two recesses 4 have a axial distance from each other, which the width of the Bearing point 2 corresponds. After the chosen presentation 1, the punctures 4 with a Deep rolling tool 5 processed. The deep rolling tool 5 consists of a tool housing 6, in which a Guide roller 7 is rotatably mounted about the axis 3. In each of the recesses 4 engages a deep rolling roller 8, wherein the two deep rolling rollers 8 to the vertical spread outwards at an angle of about 35 ° are and within the tool housing 6 on Supporting guide surfaces 9 of the guide roller 7.

By the action of the deep rolling rollers 8 on the Grooves 4 arise within the crankshaft 1 on the Reason of the punctures 4 tangential compressive residual stresses, which are represented by the arrows 10. By the Arrow 11, the reason of the punctures 4 is indicated; of the Arrow 12 indicates the Einwalzradius, which at Crankshafts for passenger car engines in sizes from 1.2 to 1.9 mm can have.

In the radial distance between the outer circumference 13 the guide roller 7 and the bearing 2 of the crankshaft 1, a sensor 14 is arranged in the present example. The sensor 14 is at a suitable location with the housing 6 connected and measures the radial distance between the outer circumference 13 of the guide roller 7 and the Bearing point 2 of the crankshaft 1. In the sensor 14th it is, for example, an eddy current sensor in miniature construction. The sensor 14 is again in the Fig. 2 shown. Here he is, for example, on one Device arm 15 of the two arms 15 and 16 having fixed deep rolling device 17 is arranged.

As already mentioned, has a single deep rolling machine a plurality of such deep-rolling devices 17, according to the number of bearings to be processed 2. The type of scissors, the two arms arms are 15 and 16 hinged at a common pivot point 18 connected with each other. The first outer ends 19 and 20 of the two arms 15 and 16 carry each other corresponding parts of a deep rolling tool 5. So is for example, at the first outer end 19 of the Gerätearmes 15, the tool housing 6 with the Guide roller 7 attached and at the opposite first outer end 20 of the second Gerätearmes 16 a Housing 21 with the two support rollers 22. In between is the crankshaft 1. According to the representation of Fig. 2 is the sensor 14 both on the Gerätearm 15 as also attached to the tool housing 6.

Between the two second outer ends 23 and 24 of the Device arms 15 and 16 is located Pressure medium cylinder 25. This pressure medium cylinder 25 generates the deep rolling force, which is used for deep rolling the Grooves 4 of the crankshaft 1 is required. The Signal of the sensor 14 is, for example, a Computer 53 transferred, stored there, in a Calculated size and passed to a controller 54, the supply of the pressure medium to the pressure medium cylinder 25 regulates. Computer 53 and controller 54 are devices which are familiar to the person skilled in the art.

Fig. 3 shows the change in distance 26 of Deep rolling rollers 8 to the bearing surface 2 of the crankshaft 1 in radial direction. Here, only the distance change 26 of both deep-rolling rollers 8 recorded together, which each a change during the deep rolling process learn their position in the direction of the two arrows 27. Out FIG. 3 shows that the two arrows 27 each in a component in the vertical direction, corresponding to the arrow 26, and into a component 28 in FIG Direction of the rotation axis 3 can be decomposed.

This type of detection is shown in FIG. 4 illustrated. When penetrating into the punctures 4 of Crankshaft 1 experienced namely the measuring rollers 38 a Measuring tool 57 at the same time a spread in the axial direction 28. As with a deep rolling tool 6 be the two measuring rollers 38 of the measuring tool 57th guided laterally in cages 33 (Fig. 5). For investigation the axial displacement of the measuring rollers 38 of the Measuring tool 57 sensors 29 are provided which for example, the size of a gap 30th between the measuring rollers 38 and the oil straps 31 a Detect crankshaft 1. The axial position of Measuring rollers 38 before the deep rolling operation makes mistakes of Pre-machining the crankshaft 1, e.g. differently deeply pierced punctures 4 recognizable. Relocation the measuring rollers 38 during deep rolling makes different Rolling depths, e.g. in consequence of different Cures in the area of the punctures 4 recognizable and serves thus the process monitoring. One of FIG. 4 appropriate arrangement is appropriate, where the Requirements for mounting sensors 29 am Tool housing 40 of a measuring tool 57 particularly are favorable. In addition, a force sensor 32, the Completing the measuring device 57, if necessary also with a displacement sensor (not shown) together acts over that of the puncture 4 during a Rotation of the crankshaft 1 covered path 34 detected becomes. The force sensor 32 is for example via a Control line 55 connected to the feed line 56, via which the pressure medium the pressure cylinder 25th is supplied. About this, the relevant specialist also common way of capturing the Working pressure, the respective height of the deep rolling force determined and monitored.

6 shows a sensor 35, similar to the sensor 14, the radial change of the distance between the both first outer ends 19 and 21 of two arms 15 and 16 recorded. In addition to the arrangement on the outside Ends 19 and 20 may be comparable to the sensor 35 Sensors may also be mounted in the measurement planes 36. Also Here is the appropriate choice of levels 36 the be left to the skilled person. For the respective Arrangement is only significant that at least the 10-fold resolution of the desired measured value is carried out.

One of the Fig. 6 largely corresponding, enlarged Representation is shown in FIG. 10. Here is between the outer end 20 and the pivot point 18 the inside of the Gerätearmes 15 a holder 58th appropriate. From the holder 58, a probe 59 jumps, For example, an inductive displacement sensor, in the direction on the Gerätearm 16 forth. The probe 59, the Distance between the two arms 15 and 16 with capture great accuracy and is thus, suitable, the Depth of penetration of the deep rolling roller 8 in the Crankshaft 1 to detect completely. The measuring signal is running via a line 60 to the computer 53, the controller 54 which in turn is in charge of the feeders 56 applied to the pressure medium cylinder 25. Of the Probe 59 detects the penetration depth of the deep rolling roller 8 with an accuracy in the measuring range of ± 0.01 mm.

Fig. 7 shows the schematic attachment 37 of a Sensor 14 to a tool housing 40. Instead of the Deep rolling rollers 8 are in the illustration of FIG. 7 Measuring rollers 38 are provided, which in their size and Arrangement with the deep rolling rollers 8 of FIG. 1 are comparable. Also, the measuring rollers 38 are of a guide roller 39 within a tool housing 40 supported. In Fig. 7 is a einschwenkbare Measuring device 41 shown. Another illustration such a pivotable measuring device 41 shows also the Fig. 8. The pivoting of the measuring device 41st is, for example, a small Pressure medium cylinder 42 causes. With the two Devices 41, shown in Figs. 7 and 8 are, they are pure measuring devices. These be in the respective bearing 2 of a crankshaft. 1 pivoted in as soon as the deep rolling tools 6 to 8 have been disengaged and then serve for Control of the deep rolling process. With appropriate Design and mounting of the device 42 e.g. at the Gerätearm 15 can also during the deep rolling the Penetration 26 of the deep rolling rollers 8 are measured and It can, as well as in the deep rolling tool 6 integrated sensor 14, the deep rolling force generated via the pressure medium cylinder 25, are regulated.

A turn different measuring device, the Fig. 9. Here, the measuring device consists of two axially in the Half separate guide rollers 43 and 44. These two Half rollers 43 and 44 are each in a housing 45th rotatably mounted. On them, measuring rollers 46 are based and 47, respectively, in punctures 48 and 49 of a Engage crankshaft 1. As can be seen in FIG. 9, the recesses 48 and 49 are different deep, according to different rolling depths. Sensors 50 are in turn via fasteners 51 similar to the Attachments 37 of FIG. 7 connected to the housing 45. The device according to FIG. 9 can also be pivoted in designed and used for the simultaneous measurement of different Einwalztiefen 48 and 49. It is provided that the two halves 43 and 44 of a Guide roller 52 in the radial direction with respect to the Crankshaft 1 can move. With each of the Guide rollers 43 and 44 associated axes of rotation is a Sensor 50, for example an eddy current sensor, related to the relocation of the system relative to Storage location 2 determined.

LIST OF REFERENCE NUMBERS

1

crankshaft

2

depository

3

axial direction, axis of the crankshaft

4

puncture

5

Rolling tool

6

tool housing

7

leadership

8th

Fixed roller

9

guide surface

10

tangential residual compressive stresses

11

Reason of the puncture

12

Einwalzradius

13

external scope

14

sensor

15

device arm

16

device arm

17

Deep rolling unit

18

pivot point

19

first outer end

20

first outer end

21

casing

22

supporting role

23

second outer end

24

second outer end

25

Pressure cylinder

26

distance change

27

change of position

28

axial direction

29

sensor

30

gap

31

oil collar

32

force sensor

33

Cage

34

path

35

sensor

36

measuring plane

37

attachment

38

measuring rollers

39

leadership

40

tool housing

41

swiveling measuring device

42

Pressure cylinder

43

leadership

44

leadership

45

casing

46

measuring roller

47

measuring roller

48

rolling depth

49

rolling depth

50

sensor

51

attachment

52

leadership

53

computer

54

regulator

55

control line

56

feeder

57

measuring tool

58

holder

59

probe

60

Measurement line

Claims (7)

1. Apparatus for deep rolling recesses and radii which delimit the journal bearings (2) of crankshafts (1) in the axial direction respectively on both sides, with at least one deep-rolling tool (5) of a deep-rolling machine having a plurality of deep-rolling tools for the recesses (4, 48, 49) and radii on both sides of the journal bearings of crankshafts, wherein the deep-rolling tool is provided at mutually opposing, first outer ends (19, 20) of two scissors-like equipment arms (15, 16) hinge-connected approximately at their longitudinal centre and has a tool housing (40), in which a guide roller (7, 43, 44, 52) and at least one deep-rolling roller (8) are rotatably supported and the guide roller has a radial spacing from the journal bearing of the crankshaft, and between the two second outer ends (23, 24) of the equipment arms there is provided a pressure-medium cylinder (25) to produce the deep-rolling force, characterised in that

   in the radial spacing between the guide roller (7, 43, 44, 52) and the journal bearing (2) there is provided a sensor (14, 29) to determine the depth of penetration of the deep-rolling roller (8) in the recesses (4, 48, 49) and radii of the crankshaft (1) or between a tool housing (40) and a measuring roller (38) there is provided a sensor (29) to determine the displacement (28) of the measuring roller (38) in the axial direction of the crankshaft (1),

   each of the sensors (14, 29) is connected to a computer (53) which saves the measured values and converts them into operands and the computer (53)

   is connected to a plurality of control elements (25, 54, 56) of which at least

   one controls the revolution of the crankshaft (1) and at least

   one other (54) controls the loading of the pressure-medium cylinder (25) to produce the deep-rolling force

   as a function of the revolution of the crankshaft (1) and the operands evaluated by the computer (53).
2. Apparatus according to Claim 1, wherein the deep-rolling tool (5) is provided at mutually opposing, first outer ends (19, 20) of two scissors-like equipment arms (15, 16) hinge-connected approximately at their longitudinal centre and between the two second outer ends (23, 24) of the equipment arms (15, 16) there is provided a pressure-medium cylinder (25) to produce the deep-rolling force, characterised in that

   between the two first outer ends (19, 20) of the equipment arms (15, 16) there is provided at least one sensor (14, 35, 50, 58, 59) to determine the depth of penetration of the deep-rolling roller(s) (8) in the recesses (4, 48, 49) and radii of the crankshaft (1),

   the sensor (14, 35, 50, 58, 59) is connected to a computer (53), which saves the measured values and converts them into operands, and the computer (53)

   is connected to a plurality of control elements (25, 54, 56) of which at least one

   controls the revolution of the crankshaft (1) and at least

   one other (54) controls the loading of the pressure-medium cylinder (25) with a pressure medium to produce the deep-rolling force

   as a function of the revolution of the crankshaft (1) and the operands evaluated by the computer (53).
3. Apparatus according to Claim 2, characterised in that the sensor (14, 35, 50, 58, 59) is provided in different measuring planes (36) along the equipment arms (15, 16).
4. Apparatus according to one of Claims 1 to
   3,characterised in that the sensor (14, 35, 50, 58, 59) is

   an inductive sensor,

   a triangulation sensor which functions optically,

   a digital path measuring sensor,

   a potentiometer or

   an ultrasound sensor.
5. Apparatus according to Claim 4, characterised in that the triangulation sensor is constructed using a laser design.
6. Apparatus according to Claim 4, characterised in that the digital path measuring sensor or the potentiometer are constructed as capacitative devices operating according to the eddy current method.
7. Apparatus according to one of Claims 1 to 6, characterised in that the respective sensors (14, 35, 50, 58, 59) have at least a tenfold resolution with a measuring range of approximately 1 mm, where the measured value of the rolling depth lies between 0.1 and 0.9 mm.

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