Blanking and forming assembly for production of splices and press using said assembly

Abstract

 A blanking and forming assembly (10) to be associated to a press (50) to make splices (1) from a metal foil (L) is disclosed, comprising a shaping die (11) cooperating with a punch (12) slidingly coupled in a punch-guide (13) associated to a driving mechanism (14). The punch-guide (13) is removably associated to the driving mechanism (14) through joining means (21) adapted to allow the connection of punch-guides of different sizes warranting the alignment along the axial forming direction (15) defined by the punch (12).

Description

[0001] The present invention relates to a blanking and forming assembly to be associated to a press, particularly adapted to make splices from metal foils.

[0002] The present invention relates to a press using said assembly as well.

[0003] It is known that in harnesses of electric and electronic circuits connection elements are used, commonly called splices, which are used for connecting conductive leads comprising, for instance, the terminals of electric or electronic components or the ends of conductive cables.

[0004] An example of splice is shown in Figure 1 and is generally indicated with numeral 1, where one can see that the splice comprises a crop cut from a suitably shaped foil, having housings 2 where the terminals to be connected are received, like two possible applications shown in Figures 2 and 3.

[0005] On the inwardly bent lateral edges 3 of splice 1 there is a suitable saw-toothed shaping enhancing the grip to the terminals to be connected inserted in the housings 2 when the upper and lower side of the splice are squeezed.

[0006] To this purpose working machines are provided, mainly comprising presses allowing to obtain splices from coil wound metal foils preferably made of brass. Such presses carry out sequentially the foil blanking, bending and forming steps to obtain the final product as shown in Figure 1.

[0007] The prior art presses have a blanking and forming assembly shown in Figures 4 and 5, comprising a shaping die 8 cooperating with a punch 4 associated to a punch-holder 5 slidingly moving said punch 4 inside a punch guide 6.

[0008] More particularly, the punch-guide 6 is securely fixed to a support 7 on which the punch-holder 5 is sliding, through rivets or other fastening means so as to make an integral body that cannot be quickly and easily disassembled.

[0009] Alternatively the punch-guide 5 may be integral with the support 7 from which it is worked by machine tools.

[0010] The blanking and forming assembly is shown in Figures 4 and 5 with the punch 5 in two different positions relative to the punch-guide 6, defined by the driving mechanisms of a press to which the assembly is applied.

[0011] When the size of the metal foil fed to the press and therefore the size of the splice to be made is changed, it is necessary to change the entire blanking and forming assembly in order to fit to the change of production.

[0012] This involves the inconvenience of the operators' loss of time and loss of output due to the machine stop, because this operation requires a not negligible time.

[0013] Moreover, the above-described prior art embodiment involves the need to keep in stock a plurality of complete blanking and forming assemblies with the consequent investment and maintenance costs.

[0014] Such costs may sometimes be rather high because said assemblies comprise components worked with a high degree of precision.

[0015] Another inconvenience is that when the assembly is changed, proper regulation operations are required, to adjust the stroke of the punch and the punch-guide relative to the shaping die.

[0016] The present invention aims at overcoming said inconveniences.

[0017] A first object of the invention is to provide a blanking and forming assembly to be connected to a press to make splices, allowing to reduce the set-up times when changing the production.

[0018] Another object of the invention is to reduce the time required for the adjustment operations when the production is changed.

[0019] A further object of the invention is to reduce the costs of the spare parts in stock required to produce splices of different kinds.

[0020] The foregoing objects are attained by a blanking and forming assembly to be associated to a press for making splices from metal foils, that according to the contents of the main claim, comprises a shaping die cooperating with a punch slidingly coupled in a punch-guide associated to a driving mechanism, and is characterized in that said punch-guide is removably associated to said driving mechanism through joining means adapted to allow the connection of punch-guides of different size and to warrant alignment along the axial forming direction defined by said punch.

[0021] According to a preferred embodiment the driving mechanism comprises a punch guide support member to which a punch-holder is slidingly associated.

[0022] The joining means comprise a fixed counterpart member belonging to the support member to which the punch-guide is connected through screw means.

[0023] The punch-guide has at least a portion of its outer surface with a saw-toothed profile mating a corresponding saw-toothed zone of the press.

[0024] Finally, the punch-guide has a cam moving a mechanical cam follower belonging to the press, which is used to bend the foil in one of the intermediate working steps.

[0025] The above-described blanking and forming assembly is preferably applied to a press.

[0026] Advantageously to set up again the press after a production change, it is sufficient to change only the punch and the corresponding punch-guide to mate the new shaping die without changing the entire blanking and forming assembly.

[0027] The foregoing objects and advantages will be better understood from the following description of a preferred embodiment of the invention given as an illustrative, but non-limiting example with reference to the accompanying sheets of drawings in which:

• Figure 1 is an isometric view of a splice made by the press of the invention;
• Figures 2 and 3 show two possible applications of the splice of Figure 1;
• Figures 4 and 5 show a detail of a prior art blanking and forming assembly;
• Figure 6 is an isometric view of the blanking and forming assembly according to the present invention;
• Figure 7 is an exploded view of Figure 6;
• Figure 8 shows the blanking and forming assembly of Figure 6 applied to a press;
• Figures 9 and 10 show different views of Figure 8; and
• Figures 11 to 20 show diagrammatically the working cycle to obtain a splice by the press of the present invention.

[0028] The blanking and forming assembly of the invention is shown in Figures 6 and 7 where it is generally indicated with numeral 10.

[0029] The assembly substantially comprises a shaping die 11 cooperating with a punch 12 which is sliding in a punch-guide 13 associated to a driving mechanism generally indicated with numeral 14.

[0030] In this way an actual forming direction 15 intersecting the shaping die 11 is defined for said punch 12.

[0031] As to the driving mechanism 14, it comprises a support member 16 to which a punch-holder 17 sliding in contact with support 16 along the axial forming direction 15 is coupled.

[0032] The punch-holder 17 and the support member 16 are provided with pivots 19 and 20 respectively, allowing to connect them to driving means 18 of a press 50 to which the blanking and forming assembly 10 is associated.

[0033] In this way, the support member 16 and the punch-holder 17 are both moved independently from one another along the same above-mentioned axial forming direction 15.

[0034] According to the present invention, the punch-guide 13 is removable associated to the driving mechanism 14 through joining means generally indicated with numeral 21, allowing the connection of punch-guides of different size warranting the alignment along the axial forming direction 15 defined by said punch 12.

[0035] The joining means 21 comprise a fixed counterpart member 22 belonging to the support member 16, to which the punch-guide 13 is connected through screw means 23.

[0036] Connection and disconnection of the punch-guide 13 when required is carried out by acting on the screws 23, at the same time connecting or disconnecting the punch 12 relative to the punch-holder 17 by coupling the hole 12a to the gauge pin 24 of the punch-holder 17.

[0037] It is, for instance, clear that when changing production in view of a change of the size of the splice 1 to be obtained, the press must be equipped with a different punch 12, a different punch-guide 13 and a different shaping die 11.

[0038] As to the punch-guide 13, it comprises a main body 25 having a channel 26 slidingly receiving the punch 12 and a contact surface 27 mating a corresponding abutting surface 28 made in the fixed counterpart 22.

[0039] Near the abutting surface 27 there is a zone with a saw-toothed profile 29, not shown in the drawings, mating a corresponding zone 30 of the press as shown in Figures 9 and 10.

[0040] As it will apparent in the following, such zones 29, 30 allow the blanking operation of the foil L to confer to the splice 1 so obtained, the saw-toothed shape 3 of its lateral edges as shown in Figure 1.

[0041] Finally, on the punch-guide 13 a cam 31 is provided, cooperating with a cam follower 32 belonging to an opposing finger 33 pivoted to the press 50 as better shown in Figures 12 to 20.

[0042] The press 50 to which the blanking and forming assembly 10 of the present invention is applied, is shown in the views of Figures 8, 9 and 10.

[0043] Said press substantially comprises a frame 51 where the following elements are defined:

• a feeding unit 52 of the foil L to the blanking and forming assembly 10;
• driving means 18 for the support member 16 and the punch-holder 17, preferably but not necessarily, consisting of mechanical linkages 53 connected to the shafts of relevant motors;
• a die-holder 54;
• a housing 56 slidingly receiving the blanking and forming assembly 10 in which said saw-toothed shaping zone 30 is provided allowing blanking of the foil L;
• an opposing mechanical member 33, associated to elastic means 57, comprising a cam follower 32 cooperating with the cam 31 of the punch-guide 13 to move said opposing member 33 during the blanking and forming steps.

[0044] From the detail of Figure 10 one can see that the solution proposed by the present invention allows to have easy access to the punch-guide 13 to carry out the change operations simply acting on the screws 23 by suitable handling means.

[0045] This operation allows to avoid disassembling of the support member 16 and the punch-holder 17 keeping them constrained to the driving means 53 so as to minimize any subsequent calibrating operation.

[0046] The working cycle known per se, to obtain the splices 1, comprises a sequence of steps that will be described hereinafter with reference to Figures 11 to 20 where said steps of the cycle are diagrammatically shown.

[0047] The first step shown in Figures 11 and 12, is the insertion of the foil L through the feeding unit 52, in the intermediate zone defined between the punch-holder 17 and the shaping die 11.

[0048] From this position the punch 12, the support member 16 and the punch-holder 17 are moved downwards as shown in Figures 13 and 14 to carry out blanking of the foil L obtaining a crop L1 having the lateral edges cut with a saw-toothed profile 3.

[0049] Such saw-toothed profile is obtained by interaction of the saw-toothed zones 29-30 provided on the punch-guide 13 and the press structure 50 respectively.

[0050] The so obtained crop L1 is then bent to obtain an U-shaped element L2 as shown in Figures 15 and 16.

[0051] The bending operation is obtained through the combined action of advancement of the punch-guide 13 and the punch-holder 17 against the below-positioned opposing member 33 received in the channel 26 of the punch-guide 13.

[0052] The further forward movement of the support member 16 and more particularly of the punch-guide 13 associated to it, causes the movement of the opposing member 33 as shown in Figure 18, in view of the thrust received by the elastic means 57 together with the interaction between cam 31 and cam follower 32.

[0053] The movement of the opposing member 33 causes the shaped element L2 to fall by gravity inside the die 11, while at the same time the punch-guide 13 and the punch 12 move further toward said die 11.

[0054] Finally, as shown in Figures 19 and 20, the punch 12 advances beyond the punch-guide 13 to press against the shaped element L2 carrying out the forming step according to the required profile defined by the shape of the die 11 to make the splice 1.

[0055] From this position the support member 16, the punch 12 and the punch-guide 13 are moved upwards and return to the starting position of the cycle as shown in Figure 11.

[0056] From the foregoing it is clear that the assembly of the present invention fully attains the above-mentioned objects and advantages.

[0057] In the constructional stage of the assembly of the invention many implementing variations may be made, for instance comprising joining means of a different type known in the mechanical field or different geometries of the various elements constituting the blanking and forming assembly.

[0058] It is, however, to be understood that these and further variations even when neither described nor illustrated, are to be considered covered by the present patent when falling within the scope of the appended claims.

Claims

1. A blanking and forming assembly (10) to be associated to a press (50) to make splices (1) from a metal foil (L) comprising a shaping die (11) cooperating with a punch (12) slidingly coupled to a punch-guide (13) associated to a driving mechanism (14), characterized in that said punch-guide (13) is removably associated to said driving mechanism (14) through joining means (21) adapted to allow the connection of punch-guides of different size warranting the alignment along the axial forming direction (15) defined by said punch (12).

2. The blanking and forming assembly (10) according to claim 1), characterized in that said driving mechanism (14) comprises:

- a support member (16) for said punch-guide (13);

- a punch-holder (17) slidingly associated to said support member (16) along said axial direction (15);

- connection means (21) to connect said support member (16) and said punch-holder (17) to driving means (18) of said press (50) adapted to move them alternatively along said axial direction (15).

3. The blanking and forming assembly (10) according to claim 2), characterized in that said punch (12) has a through hole (12a) adapted to removably connect it to a gauge pin (24) belonging to said punch-holder (17).

4. The blanking and forming assembly (10) according to claim 1), characterized in that said joining means (21) comprise a fixed counterpart member (22) of said support member (16) and screw means (23) adapted to connect said punch-guide (13) to said fixed counterpart member (22).

5. The blanking and forming assembly (10) according to claim 3), characterized in that said punch-guide (13) comprises a main body (25) having a channel (26) adapted to slidingly receive said punch (12) and a contact surface (27) mating a corresponding abutting surface (28) made in said fixed counterpart member (22).

6. The blanking and forming assembly (10) according to claim 1), characterized in that at least a portion of the outer surface of said punch-guide (13) has a zone (29) with a saw-toothed profile mating a corresponding saw-toothed zone (30) of said press (50) to carry out the blanking operation of said foil (L) during the movement of said punch-guide (13).

7. The blanking and forming assembly (10) according to claim 1), characterized in that said punch-guide (13) comprises a cam (31) cooperating with a cam follower (32) belonging to an opposing mechanical member (33) of said press (50) adapted to carry out the bending step of said foil (L) after the blanking step and before the forming step in said die (11).

8. A press (50) using a blanking and forming assembly (10) according to the preceding claims, characterized by comprising a frame (51) with the following means:

- a feeding unit (52) of said foil (L) to said blanking and forming assembly (10);

- driving means (53) of said support member (16) and said punch-holder (17);

- a die-holder (54);

- a housing (56) slidingly receiving said blanking and forming assembly (10) having said zone (30) with saw-toothed profile allowing the blanking operation of the foil (L);

- an opposing mechanical member (33) associated to elastic means (57) comprising a cam follower (32) cooperating with said cam (31) of said punch-guide (13) to move said opposing mechanical member (33) during the blanking and forming steps.

9. The press (50) according to claim 8), characterized in that said driving means (18) consist of linkages (53) mechanically connected to corresponding shafts of electric motors.

Drawing