Field of the Invention

The present invention concerns a press, particularly for shaping or working blanks or work pieces, including a press frame with a press space, a first tool part and a second tool part.

Furthermore, the invention concerns a method for operating a press. Background of the Invention

In connection with series production with presses it is desirable that the rate of production, i.e. the time from a blank is placed in the press until a finished item is taken out, at which time the press is ready for a new blank, is as high as possible. The higher the rate of production of the individual press, the greater production capacity, implying that a given production can be performed by fewer presses or in shorter time with the same number of presses.

WO 2010/045947 Al discloses a deep drawing press which solves the problem of attaining a faster rate of production. The press includes two tool parts of which one is displaced to a position outside the press when the item is to be ejected. Hereby is achieved that tools, press shoe etc. can be avoided lifted to a position sufficiently high so that the item can be released from the tool. This is particularly an advantage by deep items.

A consequence of the more rapid rate of production provided by the deep drawing press of WO 2010/045947 Al is that more frequent tool changes can occur as it will take less time to produce a series of items.

The deep drawing press of WO 2010/045947 is unproductive while changing tools for a new item. In a production with frequent tool changes, the full advantage of the higher rate of production provided by the machine will therefore not be achieved. Object of the Invention

It is the purpose of the invention to indicate a press with increased production capacity and a method for operating a press with increased production capacity.

Description of the Invention

According to the present invention, this is achieved by a press including a press frame with a press space, a first tool part and a second tool part, wherein the press is peculiar by including at least one additional first tool part and a first displacing arrangement which includes a first guideway and first displacing means, wherein the first displacing arrangement is adapted for displacing the first tool parts on the first guideway by the first displacing means between positions outside the press space and a pressing position within the press space such that one of the first tool parts is disposed opposite the second tool part in the press space during each pressing operation.

Furthermore, according to the present invention this is achieved by a method of operating a press which includes a press frame with a press space, at least two first tool parts and a second tool part, where each of the first tool parts are alternately displaced during operation by a first displacing arrangement between positions outside the press space and a pressing position within the press space such that one of the first tool parts is disposed opposite a second tool part in the press space during each pressing operation.

Hereby is achieved that the machine can operate alternately with the first tool parts or with any one of the first tool parts. Moreover, it is achieved that the press can be continually productive during most of the time of a tool change as it will still be capable of producing with at least one first tool part while making a second first tool part ready. The production is only to stop if the second tool is to be changed. The press and the method are particularly suited in connection with presses applied in series production. The application is particularly advantageous in connection with productions with frequent changes between production of different items as the press according to the invention enables tool changes with minimum production loss. As examples of press types suited for implementation of the invention can be mentioned: deep drawing presses, embossing presses, punching presses, bending presses and forging presses. The listed examples are not exhaustive.

During operation, one and the other of the first tool parts are alternately moved into the press space for performing a pressing operation. The finished items are ejected from the first tool part which is located at a position outside the press space. The tool part is then loaded with a new blank. This is effected simultaneously with the other first tool part performing a pressing operation in the press space. Hereby, the cycle period is substantially reduced.

In one embodiment, the press according to the invention is peculiar in that it includes two second tool parts which are displaceably provided in the press space such that they can be displaced by a first displacing arrangement arranged in the press between positions outside the press space and a pressing position in the press space.

According to a further embodiment, the press according to the invention is peculiar in that the press includes a second displacing arrangement which includes a second guideway and second displacing means, wherein the second displacing arrangement is adapted for displacing the second tool part on the second guideway by the second displacing means between positions outside the press space and a pressing position within the press space such that the second tool part is disposed opposite a first tool part in the press space during each pressing operation.

Hereby is achieved that a tool change of the second tool part can be effected in a particularly simple way.

According to a further embodiment, the press according to the invention is peculiar in that the press includes at least one additional second tool part and that the second displacing arrangement is adapted for displacing the second tool parts on the second guideway by the second displacing means between positions outside the press space and a pressing position within the press space such that one of the second tool parts is disposed opposite a first tool part in the press space during each pressing operation.

Hereby it becomes possible to produce items requiring several pressing operations before the item reaches its final shape as respective first and second tool parts can be applied as sets in pairs.

According to a further embodiment, the press according to the invention is peculiar in that the first and/or second displacing arrangement includes slides and that each tool part is placed in a slide.

Hereby is achieved that the first and second tool parts can be mounted in the press in a simple and reliable way. In the first displacing arrangement, the slides on the first guideway are connected to the first guideway by interacting guide means. By embodiments with the second displacing arrangement, the slides on the second guideway are connected to the second guideway by interacting guide means. By placing the tool parts in slides, releasing of the interacting guide means is avoided when the tool parts are to be changed. The tool changes hereby become faster and more reliable. Furthermore, better tolerances can be attained.

The tool parts are connected to the slides by interacting releasable connecting means such that the tool parts can be mounted and dismounted rapidly and in a simple way.

According to a further embodiment, the press according to the invention is peculiar in that the slides optionally are separately displaceable or include coupling means for coupled displacement between positions outside the press space and a pressing position within the press space.

By separately displaceable slides it is possible to continue production with one tool while the other tool is changed. For this purpose displacing means adapted for separate displacement of the slides are required. This complicates the structure of the displacing means.

With coupled slides, the production is interrupted during tool changes, but the displacing mechanism can be divided with regard to the slides. This will simplify the structure of the displacing means.

According to a further embodiment, the press according to the invention is peculiar in that the first and/or second guideway includes rails extending from a position at one side of the press space through the press space and to a position at the other side of the press space.

Hereby is achieved a simple way of establishing the guideways. The rails can be passive slide means interacting with contact faces, wheel or rollers on the slides or the tool parts. Alternatively, the rails can be provided with rollers or wheels upon which the slides or tool parts roll.

According to a further embodiment, the press according to the invention is peculiar in that the first and/or second guideway includes shunting tracks.

Hereby is achieved that several positions outside the press space can be established for the tool parts. This is advantageous by frequent tool changes. For example, two tool parts can be active in alternating pressing operations while a third tool part is prepared at a position where it does not interfere with the displacement of the active tool parts.

Moreover, the additional positions enabled by the shunting tracks serve as storage for tool parts such that tool changes and control of the tool part inventory can be automated. According to a further embodiment, the press according to the invention is peculiar in that the first and/or second guideway includes a closed circuit extending through the press opening. Hereby, continuous operation with different tools can be achieved.

By embodiments with a first and second displacing arrangement with first and second guideways as circuits, tool changes can be automated. The displacing means are to be adapted such that the tool parts are driven throughout the guideway circuit.

According to a further embodiment, the method according to the invention is peculiar in that the press includes at least one additional second tool part, where each of the second tool parts are displaced during operation by a second displacing arrangement between positions outside the press space and a pressing position within the press space such that one of the second tool parts is disposed opposite a first tool part in the press space during each pressing operation.

Hereby is achieved that tool changes can be automated. The method enables that the press can produce items requiring several pressing operations by different tools.

According to a further embodiment, the method according to the invention is peculiar by including a step for tool change, wherein a first and/or a second tool part is displaced by the first and/or the second displacing arrangement, respectively, to a position outside the press space, and wherein the first and/or second tool part are/is changed, and where the at least one additional first and/or at least one additional second tool part optionally continues operation.

By embodiments without the second displacing arrangement it achieved that the period of time where the press is not productive is limited only to the time for mounting the second tool part in the press space. By embodiments with the second displacing arrangement, elimination of unproductive time for the press is achieved. The press will produce at a reduced rate during preparation for a tool change but will not be unproductive.

Description of the Drawing

The invention will be explained in more detail below with reference to the accompanying drawing, where:

Fig. 1 shows a side view of a section through a press in a first embodiment;

Fig. 2 shows side view of a section through a press in a second embodiment;

Fig. 3 shows a top view of a section through a press in a first situation of operation; Fig. 4 shows a top view of a section through a press in a second situation of operation;

Fig. 5 shows a top view of a section through a press in a third situation of operation; Fig. 6 shows a top view of a section through a press in a fourth situation of operation;

Fig. 7 shows a top view of a section through a press in a fifth situation of operation; Fig. 8 shows a top view of a section through a press in a sixth situation of operation; Fig. 9 shows a top view of a section through a press in a seventh situation of operation;

Fig. 10 shows a top view of a section through a press in a eighth situation of operation;

Fig. 11 shows a top view of a section through a press in a ninth situation of operation;

Fig. 12 shows a top view of a section through a press in a third embodiment;

Fig. 13 shows a top view of a section through a press in a situation of operation of preparing a change of a first tool part;

Fig. 14 shows a top view of a section through a press in a situation of operation of changing the one first tool part and a second tool part;

Fig. 15 shows a top view of a section through a press in a fourth embodiment; and

Fig. 16 shows a top view of a section through a press in a fifth embodiment.

In the explanation of the Figures, identical or corresponding elements will be provided with the same designations in different Figures. Therefore, no explanation of all details will be given in connection with each single Figure/embodiment. Detailed Description of Embodiments of the Invention

In the present description, the terms right and left are used in relation to the location of the individual elements on the Figures. A skilled in the art can transfer the locations to example embodiments which are e.g. laterally reversed compared with the Figures.

Fig. 1 shows a side view of a section through a press 2 in a first embodiment.

The press 2 includes a press frame 4 with a press space 6. A first tool part 8' and a second tool part 10' are provided in the press space 6. The two tool parts 8', 10' are the shaping tools for a blank 12 in the press 2. The press 2 furthermore includes several not illustrated parts which have no significance to the implementation of the invention in the press, i.e. press tables, press cylinders, press shoes etc., for example.

On Fig. 1, the second tool part 10' is in a position where under action of a blank holder 13 it is pressed against the first tool part with the designation 8' and the blank 12 thereon.

In the shown embodiment, the press 2 includes an additional first tool part 8" and a first displacing arrangement 14. The displacing arrangement 14 includes a guideway 16 and first displacing means 18.

The first displacing arrangement 14 is adapted for displacing the first tool parts 8', 8" . The first tool parts 8', 8" can be displaced alternately or in a more specific sequence between positions 20 outside the press space 6 and a press position 22 in the press space 6. On Fig. 1, the press 2 is shown wherein one of the first tool parts 8' is positioned opposite the second tool part 10' in the press position 22 such that a blank 12 can be pressed into the shape of a finished item 24.

There are positions 20 at each side of the press space 6 such that each of the first tool parts 8', 8" have a position where finished items 24 can be removed and a new blank 12 can be put on the first tool parts 8', 8" while at the same time the press is performing a pressing operation with those of the first tool parts 8', 8" which are in the pressing position 22 opposite each other. On Fig. 1, this means that the first tool part designated 8' by turns is displaced between a position 20 at the right side of the press space 6 and the pressing position 22. The first tool part designated 8" is alternately displaced between a position 20 at the left side of the press space 6 and the pressing position 22. The first tool parts 8', 8" can be coupled so that they are displaced synchronously (see Fig. 12), or be uncoupled so that they are displaced individually (see Fig. 13).

The first guideway 16 is adapted to receive and move the first tool parts 8', 8" between the positions 20 at each side of the press space 6 and the pressing position 22.

The guideway between the first tool parts 8', 8" and the first guideway 16 can be established in various known ways. It is important that the guideway has low friction in order to limit energy consumption in connection with displacement of the first tool parts 8', 8" .

For example, the first guideway 16 and the first tool parts 8', 8" can be designed with interacting contact faces with low friction which the first tool parts 8', 8" slide on between the various positions 20, 22.

The contact faces can be constituted by a roller table.

Another example can be wheels between the first guideway 16 and the first tool parts 8', 8".

The first displacing means 18 are adapted for displacing the first tool parts 8', 8" on the first guideway 16. In order that the rate of production can be high it is advantageous if the first displacement means 18 are chosen such that they can move the first tool parts 8', 8" at high speed between the individual positions 20, 22.

There are various examples of suitable first displacement means such as hydraulic, pneumatic, electric or hybrid linear actuators. Alternatively, the first guideway 16 or the first tool parts 8', 8" can be provided with driven wheels. The first displacement arrangement 14 may include several first displacing means 18 which may be driven coupled or uncoupled. Fig. 2 shows a side view of a section through a press 2 in a second embodiment.

The press 2 in the second embodiment differs from the press 2 in the first embodiment by including a further second tool part 10" and a second displacement arrangement 26 including a second guideway 28 and second displacing means 30.

On Fig. 2, the second tool part with the designation 10' is in a position where under action of a blank holder 13 it is pressed against the first tool part with the designation 8' and the blank 12 thereon. In this position, the second tool part with the designation 10' can be released from the second guideway 28.

The second displacing arrangement 26 is adapted for displacing the second tool parts 10', 10". The second tool parts 10', 10" can be displaced alternately or in a more specific sequence between positions 20 outside the press space 6 and a press position 22 in the press space 6. On Fig. 2, the press 2 is shown wherein one of the second tool parts 10' is positioned opposite a first tool part 8' in the press position 22 such that a blank 12 can be pressed into the shape of a finished item 24. There are positions 20 at each side of the press space 6 such that each of the first tool parts 8', 8" and tool parts 10', 10", respectively, have a position where finished items 24 can be removed and a new blank 12 can be placed on the first tool parts 8', 8" or the second tool parts tool parts 10', 10" while at the same time the press is performing a pressing operation on the one of the first tool parts 8', 8" and the one of the second tool parts 10', 10" which are in the pressing position 22 opposite each other.

On Fig. 2, this means that the said one of the second tool parts designated 10' by turns is displaced between a position 20 at the left side of the press space 6 and the pressing position 22. The one of the second tool parts designated 10" is alternately displaced between a position 20 at the right side of the press space 6 and the pressing position 22. The second tool parts 10', 10" can be coupled so that they are displaced synchronously (see Fig. 12), or they are uncoupled so that they are displaced individually (see Fig. 13).

The said second embodiment has a particular advantage in connection with making items where two pressing operations are required on each item with different tools, before the items reaches its final shape. The first tool part with the designation 8' and the second tool part with the designation 10' together form a set that constitutes the first tool. In the same way, the first tool part with the designation 8" and the second tool part with the designation 10" together form a set that constitutes the second tool.

The first time, the blank 12 is pressed with the first tool to a half-finished item after which respective tool parts 8', 8", 10', 10" are displaced to positions 22 outside the press space 6 and the pressing position 22, respectively, such that the semi-finished item can be pressed into a finished item 23 with the second tool.

In this way items that require several pressing actions can be produced in one and the same press 2 without changing the press 2 between each pressing operation. Investing in two presses 2 is avoided. Instead, only one additional tool is needed for performing the task with one press 2 according to this second embodiment of the invention.

Moreover, it is not necessary that the producer has storage capacity for storing semi- finished items as one achieves to produce finished double-pressed items in the same press 2.

The blank 12 receives its first pressing by the first tool part with the designation 8' and the second tool part with the designation 10' in the pressing position 22. At the same time, the first tool part designated 8" is provided in a position 20 at the left side of the press space 6 why the first tool part 8" can be loaded with a blank 12. Moreover, the second tool part designated 10" is provided at a position 20 at the right side of the press space 6 where a preceding finished item 24 can be ejected. Thus the first tool part 8" does not interfere with the ejection and the second tool part 10" does not interfere with preparation of a new blank 12.

In the shown second embodiment, loading and ejection occurs alternately on one and the other side.

By the shown disposition of the tool parts above and below each other, the blanks can be retained on the first tool parts 8', 8" by the action of gravity only, and ejection from the second tool parts can also be effected by means of the force of gravity.

The second guideway 28 is adapted to receive and move the second tool parts 10', 10" between the positions 20 at each side of the press space 6 and the pressing position 22.

The guideway between the second tool parts 10', 10" and the second guideway 28 can be established in various known ways. It is important that the guideway has low friction in order to limit energy consumption in connection with displacement of the second tool parts 10', 10".

For example, the second guideway 28 and the second tool parts 10', 10" can be designed with interacting contact faces with low friction on which the second tool parts 10', 10" slide between the various positions 20, 22.

The contact faces can be constituted by a roller table. Another example can be wheels between the second guideway 28 and the second tool parts 10', 10" .

The second displacing means 30 are adapted for displacing the second tool parts 10', 10" on the second guideway 28. In order that the rate of production can be high it is advantageous if the second displacement means 30 are chosen such that they can move the second tool parts 10', 10" at high speed between the individual positions 20, 22. There are various examples of suitable second displacement means such as hydraulic, pneumatic, electric or hybrid linear actuators. Alternatively, the second guideway 28 or the second tool parts 10', 10" can be provided with driven wheels. The second displacement arrangement 26 may include several second displacement means 30 which can be driven coupled or uncoupled.

On Figs. 1 and 2, the first tool parts 8', 8" are shown disposed under the second tool part 10' or the tool parts 10', 10", respectively. Alternatively, the first tool parts 8', 8" are disposed above the second tool part 10' or the tool parts 10', 10", respectively. This influences the way in which the blanks 12 are received and the items 24 are ejected.

Figs. 3 - 11 show a top view of a section through a press 2 in nine situations of operation during a pressing cycle. By a pressing cycle is to be understood the steps from disposition of a blank 12 in the press until ejection of the finished item 24.

The second tool part 10' and the second tool parts 10", respectively, with associated displacement arrangement 26 are not shown on Figs. 3 - 11 as it/they lie in a plane above the section. A skilled in the art will understand that the situations of operation shown in Figs. 3 - 11 can be integrated in first and second embodiments as well as the alternative embodiment, respectively, where the first tool parts 8', 8" are disposed above the second tool part 10' and the second tool parts 10', 10", respectively. Moreover, the principle in the situations of operation can be adapted to the third, fourth, and fifth embodiments of the invention described below.

Fig. 3 shows a starting situation of the press 2 where both second tool parts 8', 8" are ready for operation in positions 20 at each their side of the press space 6. A blank 12 is ready to be placed on the first tool part designated 8" . The draw pistons 32 are seen in the press space 6. On Fig. 4, the blank 12 is placed on the first tool part designated 8". The first tool part designated 8" is ready to be displaced into the press space 6 by the first displacing arrangement 14. On Fig. 5, the first tool part designated 8" is displaced to the pressing position 22 inside the press space 6. The press 2 is here ready to perform a pressing operation on the blank 12 on the first tool part designated 8". A new blank 12' is ready to be placed on the first tool part designated 8' . On Fig. 6, the first pressing operation has just been performed, and the finished item 24 is still lying on the first tool part designated 8" which is situated in the press space 6. The new blank 12' is placed on the first tool part designated 8' which is ready to be displaced by the first displacing means 18 into the press space 6. On Fig. 7, the first tool part designated 8" and the finished item 24 are displaced by the first displacing means 18 to a position 20 to the left of the press space 6. The first tool part designated 8' and the new blank 12' are displaced by the first displacing means 18 to a pressing position 22 in the press space 6. The press 2 is ready to perform the next pressing operation on the new blank 12' . At the same time, the finished item 24 is ready to be ejected from the first tool part designated 8".

On Fig. 8, the finished item 24 has been ejected from the first tool part designated 8" . At the same time, the next blank 12" is ready to be placed on the first tool part designated 8" . The next pressing operation can be performed simultaneously on the new blank 12'.

On Fig. 9, the next pressing operation has just been performed, and the next finished item 24' is still lying on the first tool part designated 8' which is situated in the press space 6. The next blank 12" is placed on the first tool part designated 8" which is ready to be displaced by the first displacing means 18 into the press space 6.

On Fig. 10, the first tool part designated 8" and the next finished item 24 are displaced by the first displacing means 18 to a position 20 to the right of the press space 6. The first tool part designated 8" and the next blank 12" are displaced by the first displacing means 18 to a pressing position 22 in the press space 6. The press 2 is ready to perform the next pressing operation on the next blank 12". At the same time, the next finished item 24" is ready to be ejected from the first tool part designated 8'.

On Fig. 11, the next finished item 24' has been ejected from the first tool part designated 8'. At the same time, the next blank 12'" is ready to be placed on the first tool part designated 8' . The next pressing operation can be performed simultaneously on the new blank 12" .

Operation of the press 2 will then continue with repetition of the steps on Figs. 6 to 11 until blankets 12 are no longer loaded into the press 2.

Fig. 12 shows a top view of a section through a press 2 in a third embodiment.

The first displacement arrangement 14 includes two slides 34', 34". The first tool parts 8', 8" are placed in each their slide 34', 34", respectively. The slides are coupled together by coupling means 36 such that they are displaced synchronously. Therefore, the first displacing means 18 only needs to be coupled to one slide 34".

The second displacement arrangement 26 (see Fig. 12) can also be provided with slides.

In an alternative embodiment (not shown) which may be combined with the first, second, fourth and fifth embodiments, respectively, the first tool parts 8', 8" are directly coupled with coupling means.

Fig. 13 shows a top view of a section through a press 2 in a situation of operation of preparing a change of a first tool part designated 8',

One first tool part designated 8' is displaced to a position 20 outside the press space 6. At the same time, production with the second first tool part designated 8" is continued. The rate of production is reduced without stopping during preparation for a tool change.

Fig. 14 shows a top view of a section through a press 2 in a situation of operation of preparing a change of a first tool part designated 8' and the second tool part 10' and additional second tool part 10', respectively.

On Fig. 14, the former first and second tool parts designated 8' and 10', respectively, are removed from the machine and new first and second tool parts designated 108' and 110' are placed in the vicinity of the press 2 for mounting.

In embodiments with only one second tool part 10' and without the second displacement arrangement 26, the new first tool part 108' is placed in the first guideway 16. The new second tool part 110' is disposed upon the new first tool part 108' . When the tool is to be installed in the press 2, the new first and second tool parts 108', 110' are displaced into the press space by means of the first displacing means 18. The new second tool part 110' is then mounted in the press space 6. Before the pressing operations are resumed, the new first tool part 108' is displaced outside the press space in order to be loaded with a blank 12 (not shown).

The production can continue until the new tool parts 108', 110' are to be displaced into the press space. As soon as the new first tool part 108' is loaded with a blank 12 (not shown), the production can be resumed simultaneously with the first tool part designated 8" being changed with an associated second tool part 10' (see Fig. 1).

In embodiments with a plurality of second tool parts 10', 10" and with the second displacement arrangement 26, the new first tool part 108' is placed in the first guideway 16, and the new second tool part 110' is placed in the second guideway 28, after which production with the new tool can be continued.

Fig. 15 shows a top view of a section through a press 2 in a fourth embodiment. In this embodiment, the first guideway includes rails 36 extending from a position at one side of the press space 6, through the press space 6, and to a position at the other side of the press space 6. Furthermore, there are provided shunting tracks 38, establishing a further position for yet an additional first tool part 8"' outside the press space 6. This is particularly an advantage in connection with tool changes.

In embodiments with a second guideway 28 and several second tool parts 10', 10", the same press can produce items that require several pressing actions in order to reach the final shape.

Fig. 16 shows a top view of a section through a press 2 in a fifth embodiment. The first guideway 16 includes a closed circuit 40 extending through the press space 6. Additional first tool parts 8"', 8"", 8"" ', 8""", 8"""' are kept in the circuit. This will provide possibility of rapid tool changes which is advantageous in connection with frequent changes in the production. In an alternative embodiment of the fifth embodiment, this includes a second guideway 28 which is formed as a closed circuit 40, and a second displacement arrangement 26 and additional second tool parts. Hereby it becomes possible to allow for frequent changes in production with no or very short interruptions in production due to tool changes.

Furthermore, the closed ring 40 can be used as a carousel where the tools are in operation by turns.

Moreover, the alternative embodiment of the fifth embodiment of the press 2 can be applied when the item requires a large number of pressing actions in order to reach its final shape.