EP2320441A1 - Assembly aid for punch laminations - Google Patents

Abstract

The method involves stamping out sheets (1) from sheet strips during a process operation. The sheets are provided with recessed button holes (10) on a side of the sheets and with elevations in the form of buttons on another side of the sheets. The sheets are laminated during the process operation, and the buttons are pressed into the button holes, where circumferential geometries of the button holes and the buttons are varied, where the buttons comprise round geometry, and the button holes comprise oval geometry. The button holes and the buttons are undulated or pre-punched. An independent claim is also included for a device for performing a method for manufacturing packets.

Description

The invention relates to a method for improving the accuracy of stanzpaketierten laminated cores, in particular of stanzpaketierten electrical steel cores.

The punching package of sheets is a example of the EP0133858 A1 Known method for producing laminated cores in a single operation. For this purpose, the individual sheets cut out in a known progressive tool are stacked on top of one another and joined together by an integrated method described in more detail below in the tool. Before the separation of the individual sheets, slugs are punched by an embossing process, leaving a slug hole in the form of a blind hole in the single sheet. In this hole, the slugs of the individual sheet produced in the next punching are pressed during the cutting process. The strength of the resulting composite sheet is dependent on the clamping force with which the slugs sit in the Butzenlöchern, which in turn depends on the dimensions of slugs and Butzenlöchern. These dimensions must be in close tolerances and their temporal consistency depends on various factors such as tool wear and tolerances in the material properties of the sheets. In addition, the slugs must be manufactured and joined with sufficient positioning accuracy with respect to the slug holes. If the Maßüberschneidung from Butzen to Butzenloch too low, the composite sheet can separate again. If the Maßüberschneidung chosen too large, or the positioning accuracy of Butzen to Butzenloch is not sufficient, it comes as a function of the fluctuation of the material properties of the sheet used to clamping and tilting, so that the laminations do not always lie plane-parallel to each other and one side of the entire sheet metal composite is no longer plane-parallel to the other side. The result is either reject or the need for laborious reworking.

Also from the WO99 / 16092 is the punching package of sheet metal known. This font explicitly rejects the placement of indentations on one side and matching opposite elevations. The document also discloses an apparatus for producing such sheets in the form of a die-and-die follower with multiple work stations. The above-described disadvantages of the method according to the EP0133858 A1 does not solve the doctrine revealed in this book.

The invention is therefore an object of the invention to improve the process of Stanzpaketierens such that the committee or the required rework is minimized by mutually releasing sheets and non-plane-parallel laminated cores. Starting from the method of the type mentioned, the object is achieved by the features of the unabgängigen claims, while the dependent claims advantageous embodiments of the invention are apparent.

Through the use of a different and suitably differently shaped peripheral geometry of slug to Butzenloch, the slug is plastically deformed when pressed into the slug hole, causing only small restoring forces occur, the slug at a not exactly exact positioning of slugs to Butzenloch in the centric position of the Try to push back Butzenloches. Geoemtrie pairings such as multi-tooth geometry of Butzens and round geometry of Butzenlochs, oval geometry of the Butzens and round geometry of Butzenlochs or round geometry Butzens and oval geometry of the Butzenlochs, and other combinations such as oval or round slugs in Butzenlöchern with multi-tooth geometry conceivable. The parallelism of the top and bottom of the laminated core remains as far as possible. On the other hand, the plastic deformation of the slugs is sufficient that the clamping force in the form of non-positive and positive connection between slug and slug hole moves to such a level that a secure connection between the sheets is given.

The slugs can be pre-embossed for better dimensional stability, the slug holes are pre-punched accordingly.

To produce the sheets thus formed, the use of a follow-on composite tool that can be installed in a commercial press, proposed in several workstations at each stroke of the press at the same time Shaping and cutting out geometries, stacking the sheets and bonding each sheet to the previous sheet stack position by stamping each one or more slugs in the respective one or more slug holes.

• Fig. 1 einen Ausschnitt aus einem Blech mit einem Butzenloch in perspektivischer Darstellung;
• Fig. 2 einen Ausschnitt aus der Butzen- bzw. Butzenlochprägestation eines Folgeverbundwerkzeugs im Schnitt;
• Fig. 3 einen Ausschnitt aus einem Blechpaket schematisch;
• Fig. 4 einen Ausschnitt aus einem Einzelblech in der Draufsicht;
• Fig. 5 einen Butzenlochstempel;
• Fig. 6 einen Ausschnitt aus der Patrize.

Further details and advantages of the invention will become apparent from the following, with reference to figures explained embodiments. Show it

• Fig. 1 a section of a metal sheet with a Butzenloch in perspective view;
• Fig. 2 a section of the slug or Butzenlochprägestation a follow-on composite tool in section;
• Fig. 3 a section of a laminated core schematically;
• Fig. 4 a section of a single sheet in plan view;
• Fig. 5 a cancel hole stamp;
• Fig. 6 a section of the patrix.

In Fig. 1 is an advantageous embodiment of a located in a first side of a single sheet Butzenlochs (10) with three distributed over the outer circumference, in the otherwise circular cross-section of the Butzenlochs protruding lugs (11) to see. On the opposite second side of the single sheet a circular slug (15) can be seen.

In Fig. 2 is a section of a Butzen- or Butzenlochprägestation a follow-on composite tool for producing inventive single sheets with a recess (53) for forming a nose (11) providing embossing punch (50), a hold-down (55) and a male (56) to see , The single sheet (1) lies above the bore (57) in the male part (56). By the pressure of the descending stamping die (50) of the slug (15) and the slug hole (10) is embossed. Here, the diameter of the bore (57) and thus the outer diameter of the slugs (15) is greater than the pitch circle diameter (54) of the lugs, but smaller than the foot diameter (12) of the Butzenlochs (10). As a result, the slugs (15) clamp on the lugs (11), which they plastically deform when pressed in the Paketierstation the follow-on composite tool (not shown). The noses (11) can thereby flow into the gap, which results from the difference between the outer diameter of the Butzens and the base diameter (12) of the Butzenlochs (10).

Fig. 3 schematically shows a laminated core, which consists of the stamping of the slugs (15) in the corresponding slug holes (10) interconnected individual sheets.

Fig. 4 shows a section of a single sheet with embossed Butzenloch (10) and three evenly distributed over the hole circumference lugs (11) in plan view. Evident are the foot diameter (12) and pitch circle diameter (54).

In Fig. 5 is the corresponding die (50) of the follow-on composite tool with recesses (53) to see the formation of the noses.

Fig. 6 shows a section of the male with the circular bore (57) for forming the Butzenlochs (10).

Of course, the invention is not limited to the embodiment with lugs (11) in the slotted hole (10). Also, instead of the noses a Vielzahngeometrie in Butzenloch denkar. It is also conceivable to attach the toothing on the outer diameter of the Butzens 15 and to equip the Butzenloch circular or also with a tooth geometry.

reference numeral

1

Single sheet

10

Butzenloch

11

nose

12

Base diameter

15

slugs

50

dies

53

recess

54

Pitch diameter

55

Stripper plate

56

punch

57

drilling

Claims (8)

A process for the production of packages consisting of two or more stacked sheets, wherein the sheets of sheet metal strip punched in one operation, provided with recessed Butzenlöchern on the one and elevations in the form of slugs on the other side and layered in the same operation, wherein the slugs be pressed into the stud holes,
characterized in that
the peripheral geometries of Butzenloch and Butzen are different. Method according to claim 1,
characterized in that
the slugs have a round geometry, while the slug holes have a multi-tooth geometry. Method according to claim 1,
characterized in that
the slug holes have a round geometry, while the slugs have a multi-tooth geometry. Method according to claim 1,
characterized in that
the slugs have a round geometry, while the slug holes have an oval geometry. Method according to claim 1,
characterized in that
the slug holes have a round geometry, while the slugs have an oval geometry. Method according to claims 1 to 5,
characterized in that
the slug holes and the slugs are pre-stamped or pre-punched. Apparatus for carrying out the method according to claims 1 to 6, comprising at least one die and one male with a punch for forming slugs and a slug hole,
characterized in that
the die for producing the Butzens and the punch for forming the Butzenlochs have different geometries. Device according to claim 7,
characterized in that
Stamp and die have a Maßüberdeckung.

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