FR2479041A1 - Rotor and stator lamination punch - has stations to feed blanks, cut, slot-punch and separately stack laminations - Google Patents

Abstract

The mechanism is intended for producing rotor and stator laminations for an electric motor. It comprises a station which feeds the blanks from a supply to a station where they are aligned and then passed to a slot punching station after which the punched rotor and stator laminations are deposited at positions and respectively and then stacked to form rotors and stators. The aligning station is coupled to a circular punching press which may be swivelable and may be provided with a marking tool to punch a notch in the periphery of the lamination. The station can employ aligning elements.

Description

The invention relates to an additional station for machining blanks in an automatic installation for punching notches, consisting of a blank feeding station, an alignment station, a notching station and of empi lar stations for the rotor and stator sheets respectively, for the manufacture of notched sheets, and in particular of rotor and stator sheets for electric motors.

In known installations for punching notches, it has always been necessary until now that the blanks are threaded through their center on a mandrel. Furthermore, it was necessary that these blanks already have a circular outer contour, that is to say that the outer contour of the blanks had to be produced externally, in a separate stamping installation, equipped with a relatively expensive combined die. .

This is where the present invention comes into play, the purpose of which is to make the installation for punching the notches so that the blanks can be brought there without any particular stacking specification, for example on a wooden pallet corresponding to the European standards. In addition, the machining of blanks, both circular and square, must be possible alternately. In addition, the blanks are only previously provided with the relatively small pin hole with the drive holes. This results in savings on tool costs.

 This object is achieved according to the invention by an additional station of the type defined in the preamble, which is characterized by the fact that it is added to the alignment station located upstream of the notching station, strictly speaking, a additional station which consists of a shear to cut out the circles, capable of being brought into contact with the blank introduced to act on it.

In this installation, the circle cutter is pivotally mounted; a marking device, capable of being brought into contact with the cut blank to make a mark thereon, is mounted on the cutting shears; it is arranged in the alignment station, according to the shape given to the blank introduced, two or more centering devices which act on the blank in the radial direction; a clamping device is arranged in the alignment station in a central position above the axial hole of the blanks.

 This clamping device comprises a centering plate produced in movable form vertically by means of a cylinder with pressurized fluid and the part of the centering plate which penetrates into the axial hole of the blank has different external diameters.

 Below this centering plate is disposed a movable stripper plate.

Other characteristics of the invention will emerge from the description below of an embodiment.

 Thus, the station according to the invention can essentially carry out the following operations a) When a square blank arrives, it is first aligned in the centered position in this station, then it is cut in the round at by means of a circle cutting shear which is pivotally mounted at this work station; b) The blank then undergoes a rotation by a determined angle with respect to the previous one. This movement is intended to compensate for the difference in thickness of the sheets.

c) This rotation operation is followed by a marking on the periphery of the outer contour. This marking is used to stack the sheets in the correct position inside the motor housing to form the stator.

The invention is explained in more detail using drawings which represent, schematically for some of them, an embodiment chosen arbitrarily.

Figure 1 shows the entire installation to punch the notches, in a top view.

Figure 2 is a side view corresponding to Figure
Figure 3 is a sectional view of the alignment station with the additional station.

 FIG. 4 is a top view, corresponding to FIG. 3.

Figure 5 is a sectional view showing in detail the clamping device which intervened in the alignment station.

FIG. 6 is an enlarged representation of detail A in FIG. 5.

 Fig 7 is a similar sectional view after the blank has been removed.

Figure 8 is a top view of a blank.

The drawings show an automatic installation for punching the notches, in which a linear transport of the sheets or blanks takes place between the different stations. It goes without saying that it is also possible to apply 'inventIon to an automatic installation for punching notches in which the blanks are routed to the various stations according to a circular trajectory. For reasons of simplicity, this latter embodiment has not been shown in particular.

 The installation for punching the notches proper consists of a blank feed station 1, from which the blanks to be machined are transferred into the automatic feeding device, then arrive in the alignment station 2, in which is arranged the additional station 3 according to the invention, in the form of a shear for cutting circles.

From there, the blank arrives in the actual notching station 4, equipped with the notch punching machine 5, from which the parts of the blanks, separated into rotor and stator sheets, are directed to the following two stations of stacking, 6 for rotor sheets and 7 for stator sheets.

By 8 is designated a supply station for unpunched sheets, located upstream from the blanks feed station 1. The appropriate stack 11 of unpunched sheets can, if necessary, be automatically inserted into the post 1 feeding of the blanks, by means of a carrier system designated by 14. In the collecting station 9 is accumulated a stack of rotor sheets 12 and, in the collecting station 10, a stack 13 of stator sheets. As indicated in points and dashes, circular and rectangular or square blanks can be machined alternately in the punch installation with the notches.

 The rest of the machining process will be described with regard to a square blank. After this blank has been deposited in the supply station, for example by means of a forklift, since it has been transported in the blank supply station 1 by the conveyor system 14, it is introduced, at the by means of a conveyor device, for example of the electromagnetic type, disposed above the transpont plane in the case shown and generally designated by 47, in the alignment station 2 proper, in which is arranged according to the invention, as additional station 3, a shear to cut circles.

This alignment station 2 is shown on an enlarged scale, with the additional station 3, in FIG. 4.

 First of all, the square blank is fixed by means of centering devices 15 which are pneumatically controlled, and this by means of pneumatic pistons 16. The control of operation of the centering devices 15 is ensured here by switches limit switch 17.

 Following the centering operation, the pneumatic cylinder 18 produces a lowering of the centering plate 19 which engages in an axial hole 20 in the blank 50. During this operation, the additional station -3 is that is to say the shears for cutting circles, is in the position indicated in points and in dashes, the cutting blades 24 then being located outside the outer edge of the blank. At this time, a hydraulic cylinder 22 causes a pivoting movement towards the inside of the circle cutting shears, by the angle indicated by a. The cutting blades 24 are in permanent rotation, that is to say that with the pivoting operation of the shears, the blank 50 is attacked tangentially at the weakest section of the square, then is cut in the round. After a complete turn of the plate, the hydraulic cylinder 22 rotates the additional station 3 to return it to its so-called out of service position, indicated in points and in dashes.

 The drive plate 28 is then rotated by the motor 25 by means of the pinions 26 and 27. In this drive plate 29 are permanent magnets 20 by which a drive of the blank 50 takes place. The latter is then driven in rotation until an alignment pin 30, which is biased by a pneumatic cylinder 48, engages in a corresponding alignment hole 31 made in the blank. The blank is immobilized in this position.

It is then carried out, by a marking device 32 mounted on the shears for cutting out the circles, a marking 57 on the outer circumference of the blank 50. The marking device 32 can move in the direction of the arrow 33 and pivot in the direction of arrow 34, which allows the mark 57 to be placed in any desired position. For the adjustment of the shears for cutting the circles according to the desired diameter of the blank, a lever 35 is used. Following the adjustment of the shears for cutting the circles, the latter is blocked by means of a cylinder 36.

 When one manufactures, instead of quadrangular blanks, circular blanks, there are provided, instead of the two centering devices 15 shown, three of these elements which are offset by 1200 relative to each other.

 Regarding the rotation of the blanks, the following should be mentioned again.

 As already indicated, the rotation of the blanks takes place by means of a motor 25, pinions 26 and 27, as well as the drive plate 28, on which permanent magnets 20 are provided. The operation is completed after the alignment pin 30 is snapped into the alignment hole 31 of the blank.

Finally, the blank is conveyed, by means of the conveyor system 47 to the notching station 4 proper, in which the stator sheet is notched and separated. Then the two separate parts are transported again by the conveyor system and the rotor sheet is deposited in the stacking station 6, while the stator sheet is deposited in the stacking station 7. During transport, the index bolt 37 is briefly actuated, i.e. this index bolt 37 comes out of the indexing hole provided in the divider disc 38. As a result, the entire system is rotated by the friction lining 39, c '' i.e. by means of the pinions 26, 27 and by friction coupling by the lining 39 when the index bolt 37 is retracted, the motor 25 again rotates the shaft 40 and, consequently, the alignment pin 30 which is integrated into the plate 41, by the desired angle from which the blank which will be introduced immediately afterwards must be offset with respect to the previous blank.

So that the blanks are kept very stiff during the round cutting operation, the pistons of the cylinders 18 and 42 are completely displaced downwards, whereby a clamping pressure results. is exerted on the blank, between the plates 43 and 41.

The plate 43 is spring-loaded with respect to the centering plate 19, and this so that during the upward movement of the pistons of the cylinders 18, 42 and, consequently, of the centering plate 19, the blank is detached from the plate centering 19 under the effect of springs 44.

 In the pressed position of the centering plate 19, the provided cone 45 is free, that is to say that the centering plate 19 can easily rotate in its mounting device 46 (not shown in detail) during the cutting operation in a ring.

 This so-called clamping device, consisting essentially of cylinders 18, 42 and of the centering plate 19, is shown in more detail in FIGS. 5 to 7.

By the axial hole 20 which is formed there, the blank 50 is precisely positioned by the centering plate 19. In its part which penetrates into the axial hole 20, this centering plate 19 is produced with stepped diameters which are designated by d2 and dl. The purpose of these different diameters is as follows
During the actual round cutting operation, the cutting blades 24 of the shears for cutting circles, the year 50 is rigorously centered at its axial hole 2C by the diameter d2 of the centering plate 19. As a result from the cutting operation, the cylinder 42 is actuated and, under these conditions, the centering plate 19 is raised to a sufficient extent so that the blank 50 comes to apply around the part of diameter d1.

So that the blank 50 is detached from the diameter portion d2, there is provided a stripper plate 43 which is relatively mobile on the centering plate 19, in a determined coaxial play, by means of bolts 51 and socket nuts 52 .Between the stripper plate 43 and the centering plate 19 are sprung with springs 44. It is thus ensured that the fia-n 50 will be held securely on the plate 41 until it reaches, as shown Figure 7, the region of smaller diameter dl of the centering plate 19. At this time, the stripper plate 43 is driven simultaneously upwards by the nuts S sleeve 52 and away from the blank 50.This spacing process is shown in Figure 7. It is then carried out the actual operation of alignment of the blank 50, by rotating each blank by a determined angle with respect to the previous blank. The actual raising and lowering movement for the centering plate 19 is then provided by the upper pneumatic cylinder 18.

 In the pressed position of the centering plate 19, that is to say as long as the shears for cutting the circles cut the blank, the two cylinders 18 and 42 are actuated. Therefore, the spring 53 is compressed and the cone 45 is free, that is to say that the spindle 54, on which the centering plate 19 is fixed, can rotate freely by means of the radial bearing 46 or the bearing axial.

 Following the cutting operation, the cylinder 42 is first actuated in the manner already described, which triggers the upward movement of the centering plate 19. Under these conditions, the cone 45 is closed by the spring 53 and, in this way, the centering plate 19 can no longer rotate, that is to say that it retains its position relative to the angular adjustment.

 In the top view of the blank of FIG. 8, the direction in which the shear for cutting out the circles pivots inwards is indexed by arrow 55 and makes a substantially tangential start. After a little more than one turn, the shears swivel away. Then the drive plate 28 with the permanent magnets 29 incorporated therein is rotated, until the alignment pin 30 engages in the hole 56. After this operation, a mark 57 is made on the outer circumference of the blank 50 by the marking device 32. This mark is only cut when the blank 50 is immobilized by the alignment pin 30 in the hole 56 cut in the blank 50. that the stator plate which is going to be stamped comprises, for the operation of bundling and stacking, a notching shank, not being suitable for any error, this stacking notch being cut each thread, relative to the square starting blank, in a position offset by a determined angle with respect to the previous blank, for example 90 '.

By this effect, the difference in sheet thickness, which is frequently manifested by the rolling bearing, is automatically compensated for by the indicated operation, so that it is produced, at the stacking station 7 for the stator sheets, a stack suitable for stacking and packaging, comprising the cut-out stacking notch 57.

So that the dimensions of the accessories on the installation for punching the notches can always be the same, an axial hole 20 and drive holes 58 qualified as unit are provided. These holes 20, 56 and 58 are already made before the introduction of the blanks into the installation for punching the notches.

The final axis hole is indicated in points and in dashes in FIG. 8 and designated by 59: it can also be made inside the installation for punching the notches, or subsequently by a machine. punch separate.

Claims (14)

1. Automatic installation for punching the notches, consisting of a blank feed station, an alignment station, a notching station and stacking stations for the rotor and stator sheets respectively, for the manufacture of steel sheets, and in particular of rotor and stator sheets for electric motors, characterized in that it is added to the alignment station (2) located upstream of the notching station (4) proper, additional station (3) which consists of a clsanlle cutting out the circles, capable of being brought into contact with the blank introduced to cut it out.  2. Installation for punching the notches according to the reverse dication 1, characterized in that the shears for cutting out the circles are pivotally mounted.  3. Installation for punching the notches according to claim 1 or 2, characterized in that a marking device (32), capable of being brought into contact with the cut blank to form a mark thereon, is mounted on the shears. cut out the circles. 4. Installation for punching the notches according to any one of claims 1 to 3, characterized in that it is disposed in the alignment station (2), according to the shape given to the blank introduced, two or more centering devices (15) which act on the blank in the radial direction.  5. Installation for punching the notches according to any one of claims 1 to 4, characterized in that the transport of the blank through the various stations is carried out by means of a common tra # nsporteur device (47) disposed of one end to the other of the installation to punch the notches.  6. installation for punching the notches according to claim 5, characterized in that the conveyor device (47) is constructed in a manner known per se on an electromagnetic basis.  7. Installation for punching the notches according to any one of the resales cations 1 to 6, characterized in that a clamping device (49) is disposed in the alignment station # (2) in the central position above the axial hole (20) of the blanks (50j.  8. Installation comprising a clamping device according to claim 7, characterized in that this device comprises a centering plate (19), which is produced in vertically movable form by means of a cylinder with pressurized fluid. Installation comprising a clamping device according to claim 7 or 8, characterized in that two pneumatic cylinders (18 and 42) mounted one after the other cooperate with the centering plate (19). 10. Installation comprising a clamping device according to any one of claims 7 to 9, characterized in that the part. Of the centering plate (19) which penetrates into the axial hole (20) of the blank (50) has diameters different exteriors (dl, d2). 11. Installation comprising a clamping device according to claim 10, characterized in that the upper outside diameter (d2) is larger than the outside diameter (dl) and cooperates without play with the diameter of the axial hole of the blank (50 ). 12. Installation comprising a clamping device according to any one of claims 7 to 11, characterized in that the lower operating cylinder (42) for the centering plate (19) performs a smaller stroke than the upper cylinder (18 ). 13. Installation comprising a clamping device according to claim 12, characterized in that the stroke of the lower cylinder (42) is dimensioned such that at the end of the stroke, the blank (50) is at the diameter (dl) of the centering plate (19). 14. Installation comprising a clamping device according to any one of claims 7 to 13, characterized in that this clamping device is arranged, coaxially with the Jessous or centering plate (1vj, a stripper plate (43j which is movable to a determined extent with respect to it. 15. Installation comprising a clamping device according to claim 14, characterized in that springs (# 4) are interposed between the centering plate (19) and the stripper plate (43).