WO2008032348A1

WO2008032348A1 - Process for realising a bush for electric battery pole or terminal, apparatus for actuating said process as well as bush for pole

Info

Publication number: WO2008032348A1
Application number: PCT/IT2007/000633
Authority: WO
Inventors: Claudia Scotti
Original assignee: Aquila Piombo SRL
Current assignee: Water Gremlin Aquila Co SpA
Priority date: 2006-09-13
Filing date: 2007-09-13
Publication date: 2008-03-20
Anticipated expiration: 2009-03-13
Also published as: ITMI20061748A1

Abstract

A process for realising a bush for electric battery pole or terminal, an apparatus for actuating the process and the bush for electric battery pole this obtained comprising a first actuating step of cold molding of a substantially cylinder-shaped little metallic block, metallic crop-end (58), which is pressed between a first moving matrix (20), a second moving matrix (30) and a third molding matrix (40) provided with a punch (11), said metallic crop-end (58) laying on the upper front of the punch (11), being maintained in a vertical position inside a shaped cavity (17') of the second moving matrix (30) and wherein the first matrix (20) is suitable for giving to the metallic crop-end (58) a certain compression force, a second step wherein the punch (11) penetrates into the metallic crop-end (58) realising an internal cavity in it, and making it expand so as to form peripherical protruding ribs on the lower external end of the metallic crop- end thus obtaining a molded bush (59) and a further step wherein the molded bush (59) is released from the second matrix (30) and extracted from the first matrix (20) and is subjected to an operative step of shearing and/or milling of its ends in order to obtain a bush for a pole of a battery terminal (60).

Description

PROCESS FOR REALISING A BUSH FOR ELECTRIC BATTERY POLE OR TERMINAL, APPARATUS FOR ACTUATING SAID PROCESS AS WELL AS BUSH FOR POLE

The present invention refers to a process for realising a bush for electric battery pole or terminal, and to an apparatus for actuating the process and further to a bush for a pole.

More in particular, the present invention refers to a process and to an apparatus as defined hereinabove particularly suited for realising a semifinished product, subsequently finished, by means of a compression molding process.

It is known that in order to realise a bush for an electric battery pole or terminal in general, complex processes are actuated comprising a plurality of steps; such numerous steps involving long times for realising the bush for pole.

At present, the bushes for electric battery poles are obtained by means of a process so called of drop casting through which the obtained bush for pole initially has a form and a structure suitable for satisfying the requirements demanded to this component of the battery, but it easily undergoes to phenomena of acid sweating from the battery as a consequence of the presence of harmful blowholes in the structure of the bush itself allowing for the aforementioned acid sweating.

Further the bushes for electric battery poles are obtained by means of a process of pressure die-casting, which consists essentially of causing the fusion of the material intended for the realisation of the bush under the pression of a mould moved by a press. Both the known systems, apart from having the abovedescribed drawbacks, have dimensional inaccuracies that negatively affect the working tolerances.

As a consequence, the application of the pole or terminal to the cover of the battery occurs with difficulties in the present apparatuses for automatic supply applied to the presses for the injection/molding of the covers itself.

From the above, the drawbacks and disadvantages of the known processes are particularly evident and, in practice, also concern the pertaining used apparatuses, the complexity of which is unquestioned in consideration of the fact that the aforementioned processes concern numerous steps to be made in a predetermined and unchangeable sequence comprising first of all the fusion of the metal being used, the step of realising the bush (by drops or by means of pressure) and at last the wait needed for the cooling of the piece which, together with the previous steps, considerably extends the time of realisation.

Further, it has to be noted that the fusion of the employed metal necessarily involves accurate controls of the actuating temperature of the apparatus in order not to damage the molecular structure of the metal that has to be integral for a good working of the battery, particularly as far as the leading of the current is concerned, which takes particularly high values at the starting of the motor. Further, the actuating conditions for the realisation of the bush for pole have to be controlled accurately with particular reference to the final step of cooling, which necessarily has to be conducted gradually in order not to damage, even in this case, the structure of the obtained bush, for example in order not to cause work hardenings of the metal that would weaken the structure of the pole making it less suitable to stand to stress or to be crossed by high currents.

It is now conceived and forms the object of the present invention, a process for realising a bush for electric battery pole or terminal, allowing to remove all the drawbacks listed above both in terms of dimensional precision and aesthetic aspect, and as far as the structure of the obtained pole is concerned.

It is another object of the present invention an apparatus, allowing to carry out the abovementioned process, the realisation of a bush for a pole of battery by means of a process that can be defined "cold", since the initial step of melting of the metal is completely removed, the metal being worked at ambient temperature. Consequently the possible final step of cooling is also removed, the operative times being considerably reduced in comparison with the known processes and apparatuses. It is a further object of the present invention, the bush for pole or terminal for electric battery obtained by means of the abovementioned process and apparatus, which will be free from all those abovementioned drawbacks of the bushes for known poles or terminals providing, in such a way, an assurance of good functioning of the battery and a long lasting of the same.

Thus, the present invention constitutes a relevant improvement in comparison with the prior art, first of all since it eliminates the drawback of the insufficient compactedness of the structure of the material forming the bush itself, allows for the automatic supply of the presses that moulds the covers, improves the aesthetic appearance of the pole itself, that turns out to be of a quality extremely better than the known processes and apparatuses.

It forms therefore the main aim of the present invention to provide for a process for realising a bush for electric battery pole or terminal, essentially comprising two operative steps the first consisting in realising what can be defined a semifinished product even if practically it is already the pole almost finished, while the second, thanks to a simple shearing or milling, allows for obtaining the finished pole. The process is therefore extremely simple and does not need any control.

It forms a further aim of the present invention to provide a process of the abovementioned type in which the two cited operative steps are realised in "cold" conditions i.e. at an ambient temperature.

According to the present description, the term "cold" will be used in order to designate a process carried out without any heating or fusion of the used metal.

Another aim of the present invention is that of providing for an apparatus as abovedefined, which results extremely simple in its configuration even if it allows to carry out the steps of the abovementioned process, in particular the realising of the "semifinished product" by means of compression without any particular difficulty.

Not last aim of the present invention is that of providing for a bush for an electric battery pole or terminal which presents constant features of reliability such that a product of an upper quality compared with those presently on trade can be obtained.

Constructive and functional features of the process for realising a bush for electric battery pole or terminal can be better comprised from the following description, wherein reference is made to the enclosed tables of drawings showing a preferred embodiment thereof reported for illustrative and non limitative purposes, wherein: figure 1 shows schematically a longitudinal section view of the apparatus according to the invention preset for actuating the mould of the abovecited semifinished product; figure Ibis shows schematically a detailed section of the apparatus of figure 1; figure 1ter shows in a schematic view a longitudinal view of a molded bush of the apparatus of the invention; figure 2 shows a schematic view analogous to that of figure 1 showing exactly the molding step; figure 3 shows schematically a view analogous to that of figure

1 and 2 showing the extraction step of the so called semifinished product; figure 4 shows a schematic view in longitudinal section of figure 1 showing the pilot pins; figure 5 shows a schematic view in cross section of figure 1 according to the plane A-A and in particular of the pilot pins and of the adjustment screws; figure 6 shows a view of electric battery pole or terminal according to the present invention; figure 7 is a schematic view in cross section of figure 1 according to the plane B-B showing the push posts and other support cylinders.

Making reference to figure 1 , the apparatus according to the invention, in order to realise the aforesaid semifinished product, comprises a pumping station, referred to as a whole with 10, which is constituted essentially by a first molding matrix, referred to as a whole with 20, which is supported by not shown known means allowing for the vertical movement downwards for molding and upwards for the extraction of the obtained semifinished product.

The pumping station 10 comprises a second matrix 30 positioned below the first matrix 20, which is also movable and will be described hereinbelow, part of which, in its turn movable with respect to the matrix 30 itself, allows for the extraction of the semifinished product from the pumping station 10. Finally, the pumping station 10 is constituted by a third molding matrix 40, which is fixed, and bond in a known manner to a lower plate 50 of the press.

The first matrix 20 is essentially constituted by an intermediate crosspiece 22 held by the ram or first crosspiece 21 to which it is bond in a known manner through support means not shown in the figure; said ram or first crosspiece 21 allowing for the downward movement of the intermediate crosspiece 22, during the first step of the process, and the upward movement of the same during the second step of the process. To the intermediate crosspiece 22 a bucking block 24 is fixed having a substantially cylindrical shape, on the external surface of which the crosspiece 22' is connected having a substantially parallelepipedal shape. The crosspiece 22' is provided with adjustment screws 23' allowing for the axial adjustment of the bucking block 24; such adjustment is made manually.

The adjustment screws, shown in figure 5, are preferably four and are arranged at 90°, but also three screws arranged for example at 120° could also reach the aim.

Additionally, the crosspiece 22' is further provided with holes for matching with the centering columns 16, see figure 4, that allows, by means of conventional bushes 16', for the exact relative vertical shift between matrixes 20, 30 and 40. The bucking block 24 presents a cylindrical cavity in the centre characterised by a constant bigger radius in its upper part 24' and by constant smaller radius in its lower part 24".

In the upper part 24' of the cylindrical cavity of the block 24 a little block 25 is positioned fixed to the crosspiece 22 by means of the fixing screws 26. The little block 25 presents a substantially cylindrical cavity 27 inside which the puller punch 12 can move, its body crossing correspondent passages in the intermediate crosspiece 22 and in the ram 21.

In the lower part 24" other little blocks are arranged, respectively 29, 30, 31 and 33. Amongst the little blocks 31 and 33 a cap 32 finds its seat.

The little block 29 centrally presents a cylindrical cavity 29' in the lower part of which a pad 28 is located, on the upper surface thereof laying the lower part of the puller punch 12. The little blocks 30, 31 , 32 and 33 are bond with the little bjock

29 by means of known means. Also known means bind the little block^{^} 29 to the block 25. The little block 31 and the cap 32 present a longitudinal cavity inside which an extractor 30' moves in a longitudinal direction. jThe little block 33 presents a frustochonical shape and is characterised ;by a substantially longitudinal cavity 32' suitably shaped both for receiving the lower part of the push element 30'and for realising the form of the portion of the bush for pole of the battery coming out from the cover of the latter. i

I

I As can be noted in particular from figures 1 and 3, the longitudinal cavity 32' of the little block 33 passes from one end of the cavity itself to the other and in particular, from the upper end, the lower end of the push element 30' is inserted in it. The form of the cavity 32' is substantially cylindrical with a downward increasing radius in the upper part, ending in a substantially cylindrical portion having a small thickness at the lower end.

Always with reference to figures 1 and 3, the second matrix 30 is essentially constituted by a substantially cylindrical crosspiece 34 on the external surface of which the crosspiece 22" is connected having a tendentially parallelepipedal shape. The crosspiece 22" is provided with holes for matching with the centering columns 16 allowing for the exact relative vertical shift between the matrixes 20, 30 and 40. The crosspiece 22" is further provided with screws 14 for the connection with the crosspiece 34.

The crosspiece 34 presents internally a frustochonical shaped cavity 35 the smaller base of which is positioned in the lower part while the bigger base is exposed towards the first matrix 20, inside which the operative members of the matrix itself are arranged. The aforementioned operative members are constituted by slidable guiding means 36, center squares 37 and by the block 38; all the aforesaid elements being fixed to each other by the screws 39.

The slidable guiding means 36 strike on the internal wall of the cavity 35 of the crosspiece 34. The block 38 is constituted by a substantially frustochonical body with a cross section corresponding) to the cavity 35 of the crosspiece 34, which is made of two portions 38' and 38", each portion corresponding to half the aforesaid substantially frustochonical body. _;'

To each portion 38' and 38" of the frustochonical bod^ 38 the slidable guiding means 36 are fixed, their layout being assisted by the center squares 37 arranged between the slidable guiding means 36 and the two portions 38' and 38" of the block 38. The abovesaid layout allows for the upward movement of each of the two portions 38' and 38" moving away from each other or downward moving closer to each ofher. Thanks to the slidable guiding means 36 ψe upward and downward sliding occurs without any possibility of axial rotation of the little blocks 38' and 38". The block 38 presents inside a shaped cavity 17 having a substantially parallelepipedal shape in the upper part and cylindrical shape in the lower part, as shown in figure 1 bis. In the upper part of the abovesaid cavity 17 a matrix with separate inserts 18 is located, being realised tendentially of two halfs, and having inside a shaped cavity 17' the form of which corresponds at the bottom to that of an operative punch 11 while the upper part imitates the exterior form of the bush for pole or terminal of the battery. The lower part of the cavity 17' has a form that, going downward from the top, is substantially cylindrical, frustochonical. The lower part of the cavity 17 has a cylindrical form corresponding to the form of the corresponding portion of the operative punch. The internal walls of the upper part of the cavity 17' have recesses 13 substantially parallel to one another and defining substantially circular notches having a semicircular cross section by means of which the lower part of the pole or battery terminal according to the invention will be realised, which will correspondingly have peripherical protruding ribs with a substantially semicircular cross section, and parallel to each other.

Inside the cavity 17 separated inserts can be arranged having an interchangeable labyrinth depending on the desired shape of the pole according to the present invention. The matrix with separated inserts 18 is made integral with the block 38 by means of screws 19.

The third molding matrix 40 is constituted by a first substantially cylindrical crosspiece 41 , operating like a guiding member for the punch 11 and is fixed, in a known manner, on the upper front of a further crosspiece 43 with substantially cylindrical form. The crosspiece 41 and the further crosspiece 43 are provided with holes for the passage of the push posts 42 and of further holes for the passage of the support cylinders 46.

The crosspiece 41 , the further crosspiece 43 and a crosspiece 22"', having a substantially parallelepipedal form, are made integral with each other for example by means of screws 41'.

The system constituted by the elements 41 , 43 and 22"' is made integral with the lower plate 50 of the press by means of known kinds of bond not shown in figure. The push posts 42 have a preset height and at the lower end lean against a cap 55 moving vertically and operated by a conventional piston 44, while at the upper end cross the crosspieces 43 and 41 and are suitable to match respectively with the lower surface of the little blocks 38' and 38". The piston 44 is in turn fixed by means of known means to a blank holder plate 45 of a shock absorption system defined by a conventional pneumatic cushion not shown in figure. The support cylinders 46 are arranged on supports 47, tendentially having a cylindrical form, which lay on a blank holder plate 45. The abovesaid cylinders 46 upperly matches with the lower surface of the crosspiece 34 while at the bottom lay on the upper base, opposed to the pneumatic cushion, of the supports 47. In the foregoing, the apparatus forming the object of the present invention was mainly described and, in the following, will now be described in detail the process according to the present invention.

A metallic crop-end 58 is initially inserted at the end 17' of the matrix 18 while the first matrix 20 is lifted with respect to the second matrix 30 and the third matrix 40.

Once the metallic crop-end 58 was positioned as described above, it is subjected to a compression along a substantially axial direction during which a part of it is shaped in a way corresponding to that that will be the external portion of the bush for pole or terminal of the battery while the other end, in particular that resulting now to be the lower end, is subjected at the same time to a compression action and a radial extension action, since the compression action is combined with that causing the dilatation of the little metallic block outward for forming the abovesaid ribs.

In order to perform these compression and compression- espansion actions the first matrix 20 that, moved downward by the ram 21 , pushes downward the second matrix 30 the elements of which are arranged as in figure 1 collaborate at the same time.

The going down of the matrix 20, determines the going down of the second matrix 30 that, in its turn, moves downward the support cylinders 46 pushing downward the blank holder plate 45 consequently moving downward the piston 44 and the cap 55 integral thereto, determining the downward movement of the little column 42 laying on the cap 55. Following the downward movement of the matrix 20, the metallic crop-end 58, initially laying on the upper front of the punch 11 , is penetrated at the bottom by the punch itself and undergoes, in consequence of the relative movements of the different parts, the abovementioned compression and expansion step. In figure 2 is shown the position of the matrixes 20, 30 and 40 after the working step of the metallic crop-end 58. During this step of the manufacturing the semifinished product or molded bush 59 is obtained, shown in figure 1ter, which is constituted essentially by the bush for pole for substantially complete battery, but that will be ended in a simple following step by means of removal of two extremity areas by realising, in such a way, the bush for pole for battery 60 shown in figure 6.

Figure 3 shows the step of extraction of the molded bush from the pumping station 10. The matrixes 20 and 30 are moved away from one another; the matrix 20 is lifted from the ram 21 and the matrix 30 from the support cylinders 46 by means of the cylindrical support 47 pushed upward by the blank holder plate 45 of the pneumatic cushion. The operative members of the matrix 30, constituted by the slidable guiding means 36, the center squares 37, the block 38 and the separated inserts of the matrix 18, are further pushed upward, as shown in figure 3, by the push posts 42 as a consequence of the syncronised upward movement of the piston 44 and, consequently, of the cap 55 integral thereto thus causing the opening of the inserts of the matrix 18 and allowing the molded bush 59 to be extracted. The sliding guiding elements 36 lead the entire block of the operative members upward, in the section of the cavity 35 having a growing radius causing an increase of the radius of the cavity 17' of the matrix 18. The thus caused increasing of the radius allows to free the molded bush 59 remaining connected to the cavity 32'. The molded bush 59 is then pushed downward by the puller punch 12 and is then moved away from the pumping station by means of a compressed air blow coming from a side of the roomcomprised between the matrixes 20 and 30 (system not shown in the figure).

Since the process occurs in cold conditions, as specified above, no waiting time is needed for cooling as in the known processes and the molded bush 59 can be directly moved to the final station in which it is finished after the steps of shearing and milling, in order to its final form referred to with 60 in figure 6.

Additionally, the quality of the obtained product turns out to be high both thanks to the centering system allowing for a constant regulation of the position of the first matrix with reference to the second and thanks to the centering columns allowing for a correct relative vertical shift between the matrixes 20, 30 and 40.

Not less important is the aspect concerning the assembly and disassembly of the components, such as during maintenance operation; in fact the modular structure of the apparatus allows for a simple and easy disassembly of the components at low costs.

From the above description the advantages deriving from the process and apparatus according to the present invention are evident, since the bush for pole for batteries 60 thus obtained is free from the drawbacks of the traditional bushes for poles, such as the process and apparatus according to the present invention.

Despite the invention was described above with particular reference to only one embodiment with illustrative non limitative purposes, numerous modifications and changes will be evident for a technical expert in the light of the above description. Therefore, the present invention intends to cover all the modifications and changes falling within the spirit and in the scope of protection of the following claims.

Claims

1. A process for realising a bush for electric battery pole or terminal, an apparatus for actuating the process and the bush for electric battery pole thus obtained, said process being characterised in that it comprises:

- a first actuating step of cold molding of a substantially cylinder-shaped little metallic block, metallic crop-end (58), which is pressed between a first moving matrix (20), a second moving matrix (30) and a third molding matrix (40) provided with a punch (11), said metallic crop-end (58) laying on the upper front of the punch (11), maintained in a vertical position inside a shaped cavity (17') of the second moving matrix (30) and wherein the first matrix (20) is suitable for giving to the metallic crop-end (58) a certain compression force;

- a second step wherein the punch (11) penetrates the metallic crop-end (58) realising an internal cavity in it, making it expand so as to form peripherical protruding ribs on the lower external end of the metallic crop-end itself thus obtaining a molded bush (59);

- a further step wherein the molded bush (59) is released from the second matrix (30) extracted from the first matrix (20) and is subjected to an operative step of shearing and/or milling of its ends in order tojobtain a bush for a pole of a battery terminal (60). /

2. The process according to claim 1 , characterised in that during the first operative step of compression of the metallic crop-end (58), because of the movement of lowering of the first matrix (20) and of the second matrix (30), said metallic crop-end (58) matching with the punch

(11) of the third matrix (40) that determines the insertion of one qf its ends in the operative cavity (32') obtained in the first matrix (20) and the simultaneous insertion of the other end in the cavity (17') of the second matrix (30) at the same time of an expansion of the corresponding terminal portion of the metallic crop-end (58).

3. An apparatus for carrying out the process according to claims 1 and 2, characterised in that it comprises a first matrix (20), which can move vertically upward and downward and is provided witfya puller punch

(12) driving an extractor (30'), operating in a cavity (32') the shape of which is complementary to the configuration of the bush for pole to be realised.

4. The apparatus for carrying out the process according to one or more of the previous claims, characterised in that it comprises a second matrix (30), made mobile in a longitudinal direction by the lowering movement of the first matrix (20) and by support cylinders (46) laid on supports (47) integral with a blank holder plate (45), inside which the operative members are arranged constituted by slidable guiding means (36), center squares (37), the block (38), constituted by a frustochonical body, and by a matrix (18) having separated inserts made movable by push posts (42) laying on a cap (55) bound to a pistone (44) bound in its turn to the blank holder plate (45) of a pneumatic cushion.

5. The apparatus for carrying out the process according to one or more of the previous claims, characterised in that the second matrix (30) cohoperates with the punch (11) fixed to a further crosspiece (43) belonging to the third matrix (40).

6. The apparatus for carrying out the process according to one or more of the previous claims, characterised in that the block (38) is constituted by two portions (38' and 38") that turn out to be movable along a longitudinal direction without any possibility of rotation around its axis, said portions being provided with a substantially parallelepipedal cavity (17) wherein said matrix (18) is positioned.

7. Apparatus for carrying out the process according to one or more of the previous claims, characterised in that the matrix with separated inserts (18) presents a shaped cavity (17') inside, the form of which corresponds at the bottom with that of the operative punch (11) while the upper part refers to the external form of the bush for pole/ (60) or terminal of the battery.

8. Apparatus for carrying out the process according to one or more of the previous claims, characterised in that the lower part of the cavity (17') has a form appearing substantially cylindrical with progressively different diameters.

9. Apparatus for carrying out the process according to one or more of the previous claims, characterised in that the internal walls of the upper part of the cavity (17') have recesses (13) substantially parallel to each other and defining substantially circular notches, having semicircular cross section, by means of which the lower part of the bush for pole or battery terminal is realised, forming peripherical protruding ribs the cross section of which is substantially semicircular and which are parallel to each other.

10. Apparatus for carrying out the process according to one or more of the previous claims, characterised in that inside the cavity (17) separated inserts are arranged constituting the matrix (18).

11. Apparatus for carrying out the process according to one or more of the previous claims, characterised in that the matrix (18) is defined by two separated inserts.

12. Apparatus for carrying out the process according to one or more of the previous claims, characterised in that the inserts constituting the matrix (18) are interchangeable.

13. Apparatus for carrying out the process according to one or more of the previous claims, characterised in that it comprises centering columns (16) passing through the holes respectively realised in the crosspieces (22'), (22") and (22"') movable along a longitudinal direction without any possibility of rotating around their axis.

14. Apparatus for carrying out the process according to claims 1 and 2, characterised in that the crosspiece (22') is provided with screws (23') for the axial adjustment of a bucking block (24) to which it is coupled.

15. A bush for electric battery pole (60) realised according to the process and by means of the apparatus according to the previous claims.