The invention relates to a tool-loader storage unit for a tool machine, in particular for a bending press. The storage unit is designed so that the tool machine may be equipped with it either by stably incorporating it in its own structure or by juxtaposing it to its own structure as a detached element.

WO2016/063579, here taken as an example of the technology industry of interest, describes a storage unit permanently attached to a bending press and a related tool-handling mechanism comprising two horizontal rails 33L, 33R on which are mounted side by side various tools 103 arranged in a row on horizontal bars 105. When a tool is to be withdrawn from the storage unit, a bottom drive first raises a bar 105 and then lowers it under the rails 33L, 33R by passing the ends thereof through recesses 1 17 set on the edges of the rails 33L, 33R. Then, the so lowered bar 105 is brought forward and at the same height as the lower table of the press, so that the tools can slide horizontally and laterally on the table and be mounted therein. With the same logic, tools are moved for the upper table of the press, but using a top drive that first raises a bar 105 of tools and then aligns it with the upper table.

EP1 160024 describes a similar tool loader unit wherein a bar bearing tools is aligned to the bending press' table by lifting it from an array of parallel and aligned bars (see figures 36 and 37).

The systems in WO2016/063579 and EP1 160024 have defects.

The arrangement of the changeable tools not only occupies a lot of space, and therefore requires a drive and a casing equally bulky, but involves two complicated separate and independent drives, one to serve each of the two tables of the press.

The main object of the invention is to propose a variant to this state of the art.

Another object is to provide a tool storage unit of the aforesaid type that is easy to construct and compact.

It is proposed a tool storage unit for a bending press comprising:

a plurality of tools organized to be picked up and mounted in a housing of a table or cross-member of the press, and a support frame for tools which

is movable vertically to horizontally align the tools to the housing and comprises a plurality of horizontal linear guides adapted to support and guide tools linearly and horizontally,

the guides being vertically offset (along the direction of vertical displacement of the frame) and preferably coplanar to each other.

The special support frame allows storing several tools on a vertical plane (various rows of tools, unlike WO2016/063579), thereby saving space and speeding up the assembly operation (the average path for a tool from the storage unit to the position of alignment with the table is shorter) .

Terms like vertical and horizontal refer to the storage unit as in use. By tools here it is meant both a punch (a tool that can be mounted on the upper table of the press), and a die (a tool mountable on the lower table of the press) and a so-called clamping (a clamp mountable on the press' table adapted to receive and tighten a punch or a die) .

Preferably the storage unit comprises two or more support frames as defined above which are spaced apart and placed in a row one behind the other in such a way that the guides of different frames are mutually parallel and spaced apart horizontally.

Preferably the two or more support frames are mutually arranged in a row of lined up frames and mounted on a movable element or table of the storage unit. The movable element or table is movable linearly back and forth to be able to move back and forth all the lined up frames, thus it is possible to bring to a predetermined and/ or reference position one of the frames and then pick up tools from it. Preferably the table or movable element is mounted on a linear guide driven by an actuator, e.g. an electric motor.

Preferably the tool storage unit comprises a lifting actuator to lift a tool supported by a frame and align such tool to a table of the bending press. The lifting actuator is adapted to lift a single frame, and with it the supported tools, up to a predetermined level by which a desired tool on the frame is horizontally aligned with the press' table (and/ or with said housing). Because on the frame there are rows of tools kept at different heights, by slightly varying the lifting height it is possible to align to the press' table a different row of tools.

By combining the lifting actuator and the actuator of the movable table or element it is possible and advantageous to move horizontally each of the lined up frames to an established position. In such established position there occurs the attachment by the lifting actuator and the frame is lifted (basically by selecting it among all the others) to the level that the desired tool's guide is aligned with the press' table or said housing. The lifting actuator's structure is therefore very simplified, and the logic and the means of handling allow to store a lot of tools in a small volume. Notice the difference with WO2016/063579, where only one row of tools is moved at a time.

Preferably, such attachment occurs by interposition or abutment of parts, i.e. e.g. a frame comprises a portion engageable into abutment by a member of the lifting actuator capable of moving vertically and pushing or pulling the frame upwards. As a simple yet effective solution, the frame's engageable portion is e.g. a portion protruding from the frame and the member of the lifting actuator is a gripping block or finger operated to translate vertically. Said protruding portion in particular is placed on the sides of the frame and/or protrudes essentially in the direction of the frame's width.

Preferably the tool storage unit comprises two vertical columns along which said member of the lifting actuator is guided vertically.

According to a preferred embodiment, the tool storage unit comprises, at a raised and cantilevered position, a tool guiding segment to which from time to time, following the lifting, any one of the guides for tools present in each frame can be aligned. For constructive simplicity, the tool guide is preferably mounted on a vertical column. When a tool guide of a frame is aligned with the tool guiding segment, a continuous rail is created that allows the guided movement of a tool from the belonging frame to the press' table or to said housing. Preferably, the tool guiding segment is mounted slightly cantilevered on a vertical column of the tool storage unit, to better mate with a corresponding tool guide mounted on the press' table. Preferably, the tool guiding segment is contained in the same vertical plane that contains the tool guides of a frame when that frame is at the reference position to be lifted up.

The tool guiding segment may be fixed or, according to a preferred embodiment, is mounted movable on the tool storage unit. The advantage is to be able to free up the space that during pressing is normally occupied by movable photocells, which align with the tools' edge. The tool guiding segment may be e.g. hinged to the storage unit or a translatable member, preferably vertically translatable. For this purpose, the tool storage unit comprises a drive for moving the tool guiding segment from a working position, wherein it can be aligned with the guides of the frames, to a rest position away from the working position for clearing that space.

Preferably the tool storage unit comprises for each frame two vertical rods, mounted e.g. on the movable table or element, which are slidably inserted in complementary apertures of elements or bushes or blocks integral with a frame, e.g. to the sides of a frame. The advantage is to keep stably vertical the frames by guiding them even during the initial stroke of the lifting.

Preferably at least one of the two vertical columns comprises a vertical linear guide engageable by a corresponding guide present on a frame only when the frame is lifted with respect to the others. Efficiently - then - the same and only vertical linear guide serves to stabilize and guide each frame when it is lifted.

Preferably the vertical linear guide extends from the top of a column to the upper edge of a frame when it rests on the movable table or element, and each frame comprises a member counter-shaped to the vertical linear guide suitable to engage with the vertical linear guide. In particular, the vertical linear guide is e.g. a linear bar and the counter-shaped element is a piece of the frame with a groove complementary to the linear bar. Preferably, for economy of parts and stability during motion, the counter- shaped element of the frame is a or each of said elements or bushings or blocks inserted into the vertical bars.

Although generally the tool storage unit may be used with the help of manual force, preferably it comprises a mounting drive for picking up a tool from the guide of a frame to which it is coupled, and for aligning it to, and mounting it on, a press' table or said housing. In particular, the mounting drive comprises a motorized member displaceable horizontally on a horizontal guide comprised in the tool storage unit, and e.g. mounted cantilevered on the vertical columns.

According to a preferred embodiment, the motorized member comprises a tool engaging head comprising two protruding horizontal pins adapted to be inserted into corresponding holes of a tool. Preferably, the two protruding horizontal pins are aligned vertically, for hooking narrow tools.

Preferably the engaging head is linearly and horizontally movable relative to the motorized member (orthogonally to the movement direction of the motorized member along the horizontal guide comprised in the tool storage unit) so as to approach or move away from a lifted up frame.

Preferably the horizontal stroke of the engaging head is adjustable or programmable, for maximum adaptation to different tools and of different thickness.

Preferably the engaging head is oscillating with respect to the motorized member about an horizontal axis parallel to the movement direction of the motorized member along the horizontal guide comprised in the tool storage unit. In this way the pins can tilt and the tool with them, thereby favoring the detachment from the press' table.

Preferably, a or each protruding horizontal pin comprises a linear, (e.g. cylindrical and/ or end) portion elongated along an axis to engage a pass- through hole present in a tool, wherein the outer surface of the linear portion comprises retractable elements capable, by translating, to protrude from, or return back into, the outer surface. The retracting elements ensure a firm and stable engagement to the tool when it is inserted around the linear portion. Preferably the retracting elements are mounted to radially translate with respect of the axis of the linear portion, to shorten the operational stroke thereof and simplify the construction of the pin. Preferably the retracting elements are connected to a movable element mounted on the pin, so that the movement of the movable element involves a translation of the retracting elements. This way it is possible to control the position of the retractable elements from a more accessible and unobstructed point of the tool.

Preferably, said movable element is placed at the end of the pin opposite to the one occupied by the linear portion, so it is easy to actuate the movable element by actuators mounted on the motorized trolley.

Generally, it is preferable that the mounting drive is able to reach the tools placed on several guides of a same frame and/or can feed the two cross-members of the press. For this purpose, e.g., the motorized member is also movable vertically, and/ or the engaging head is also vertically displaceable, along dedicated guides.

Another aspect of the invention relates to a method for applying a tool storage unit to a bending press. In particular the tool storage unit is that of the invention as defined above, in one or each of its variants. The method provides creating a tool storage unit as a detachable unit or structure and independent from the press, and physically placing the tool storage unit on one side of the press to allow the passage of the tool from the storage unit to the press and vice versa.

In particular, the method contemplates mounting on a press' table, e.g. the upper one, a guide that can be aligned with a guide present in the storage unit, and making a member for picking and mounting a tool slide on the two guides so aligned.

Further features and advantages of the invention will become more apparent from the description of a particular embodiment, illustrated in the accompanying drawings, wherein:

fig. 1 shows a three-dimensional view of a tool storage unit;

fig. 2 shows a top view of the storage unit of fig. 1 ;

fig. 3 shows a side and cross-sectional view according to the plane III-

III;

fig. 4 shows a three-dimensional view of the storage unit of fig. 1 coupled to a bending press machine;

fig. 5 shows an enlarged view of the dotted circle in fig. 2;

fig. 6 shows a three-dimensional view of a drive of the storage unit of fig. i ; fig. Figure 7 shows an enlarged view of a tool frame of the storage unit of fig. 1;

figs. 8- 1 1 show a side view of the drive of fig. 6 in various configurations;

fig. 12 shows a tool hooking pin present in the drive of fig. 6.

In the figures, equal numbers indicate equal parts; and to not crowd the figures some references are not repeated.

The tool storage unit MC is a device that can be either inseparably incorporated into the structure of a press P or a stand-alone accessory that can be coupled to, but completely detachable from, the bending press P. The second case is illustrated in Fig. 4, and it is beneficial because it is possible to equip a press P with a storage unit when the press has none available.

The press P ordinarily has a lower table or cross-member TD on which an upper or vertical table TU, which is movable vertically, presses. On the tables TU, TD, tools U are mounted, which have to be changed during machining and can be picked up from the storage unit MC.

The storage unit MC (Figures 1-3) comprises two equal base rails 10 connected to two vertical columns 12. On the rails 10 there is slidable along a horizontal axis X a table 14 driven by a motor 18 when it rotates a screw 20.

On the table 14 are installed equi-spacedly pairs of vertical guiding rods 22. The rods 22 serve as a positioning means for flat frames 30.

According to the shown preferred embodiment, a frame 30 is formed by two vertical columns 30v fixed to each other by horizontal posts 30h, so as to form a kind of frame. The vertical columns 30v are e.g. tubes or bars, and have the base fixed to the table 14. The horizontal post 30h too may be e.g. a pipe or a bar.

A frame 30 (Fig. 7) comprises horizontal guides 32, vertically offset from each other and of equal length, in which there are hung or slidingly supported tools U. The length of the guide 32 is substantially equal to the width of a frame 30. At the sides of each support frame 30 there are integrally built blocks or bushings 24, in the example three for each side and offset in height, which are slidably inserted into two respective rods 22. Therefore, the frames 30 are placed on the table 14 lined up one behind the other and parallel to each other, and the rods 22 prevent them from falling.

The storage unit MC may comprise N frames 30 (N > = 2), all in a row one behind the other (Figures 3 and 4). As a result, the guides 32 of all the frames 30 are parallel to each other, and the guides 32 of a frame 30 lie in the same vertical plane and are spaced horizontally from the guides 32 of the other frames 30. In other words, the guides 32 and the-tools U of a frame 30 are arranged in a vertical plane which is parallel to the planes containing the guides 32 and the tools U of the adjacent frames 30.

Each frame 30 comprises an integral element 46 which protrudes laterally from it and/or a column 30v, in order to be hooked up and lifted. According to the preferred embodiment illustrated here, the element 46 is a finger that is placed between the higher block 52 and the underlying one, and is protruding from a column 30v in opposite direction to the semi- plane occupied by the two columns 30v.

The storage unit MC comprises a lifting drive to vertically lift (relative to the rails 10) along a vertical axis Z (orthogonal to X) one of the frames 30, and with it the carried tools.

The lifting drive comprises an electric motor (not shown) suitable for rotating an endless vertical screw 40 (e.g. mounted inside a column 12) engaged within a counter-threaded block 42 (e.g. mounted slidably guided inside a column 12).

To the block 42 is integral a flange 44 at the bottom, which is set at a lower level than the element 46.

Each of the vertical columns 12 comprises a vertical linear guide 50 which faces the frames 30 (i.e. toward the other column) and is engageable by a corresponding guide 52 present on a frame 30. E.g. The vertical guide 50 may be a straight bar and the guide 52 a complementary groove in the block 24.

The guide 50 extends from the top of the columns 12 to the upper edge of a frame 30 considered in a non-raised position (i.e. resting on the table 14). Then the guide 50 is engaged by the guide 52 only when the frame 30 is raised with respect to the other frames. In the detail of fig. 5 there is indicated by 100 another linear guide mounted on or inside the columns 12 to stabilize the sliding of the block 42.

The storage unit MC comprises a mounting drive 60 for picking up a tool U from any guide 32 and mount it by moving it on a table TD, TS. The mounting drive 60 comprises a motorized trolley 62 movable horizontally along an axis Y on a horizontal guide 64 mounted cantilevered on the columns 12. The guide 64 is preferably fixed on the columns 12, for simplicity of construction, and is aligned with an equal guide G mounted on the back of the table TU. Generally the guide 64 can be aligned with the guide G by proper vertical positioning of the table TU, obtained by directly controlling the press P or by interfacing an electronic control unit (not shown) which manages the drives of the storage unit MC with the control unit of the press P.

The trolley 62 (Fig. 6) comprises wheels R sliding on the guide 64 and at least a head 66 for tool engagement, provided with two horizontal pins 68 projecting from the head 66 and suitable for insertion into corresponding holes of a tool U. Note that the pins 68 are particularly advantageous for tools of the "Promecam" type, that is, shaped metal pieces without coupling mechanisms to the tables TS, TD. In particular, to equip a press with the storage unit MC without having to replace the entire set of tools, it is sufficient to make in the tools two holes aligned and complementary to the pins 68. The boring is executable at any workshop and costs little.

The head 66 is movable not only linearly along Y (due to being transported by the trolley 62), but also horizontally along an axis W orthogonal to Y and parallel to X, so that it can approach or move away from a raised frame 30. The horizontal stroke of the head 66 along W can be adjusted or programmable to assume various values (compare Figures 8- 1 1), in order to fit to various thicknesses of tools U.

Preferably, a or each head 66 is also oscillating around a horizontal axis

Y2 (parallel to the Y axis) so that the pins 68 can tilt the tool U they are supporting. The inclination of the tool U favors or determines its detachment from the table TS when it is mounted on the table TS. The storage unit MC comprises on one or each column 12 a guiding segment 70 for tools U (Fig. 1). The segment 70 serves as a bridge and extension between any of the guides 32 when lifted and the housings on the tables TD, TS to accommodate the tools U (there may be also a corresponding guide mounted on the tables TD, TS). The segment 70 is mounted movable with respect to a column 12 on a drive 72 (e.g. a piston) that serves to move the segment 70 vertically.

Figures 8-9 show the trolley 62 in two different configurations: with the head 66 and the pins 68 retracted (rest position), and with the head 66 and the pins 68 moved forward (working position) to hook a tool U by threading the pins 68 into its holes.

Preferably, the horizontal stroke along W of the head 66 can be adjusted either programmable or selectable, so that the pins 68 extend more or less outwards the trolley 62 (see distances D in Figs. 10- 1 1). In particular, the head 66 can always have the same stroke along W but the position of the starting point can change.

The advantage is the ability to engage tools U, located on the frame 40, having different thickness.

The drive 60 must ensure a firm and precise grip on the tools U. For this aim, at least one of the pins 68 of a head 66 preferably has a particular structure, see Fig. 12. The pin 68 comprises a central cylindrical body 94 from which extends a cylinder 92 of lesser radius. Between the central cylindrical body 94 and the cylinder 92 a circular abutment 98 is formed on which a tool U's surface is supported. Nearly at the free end of the cylinder 92 there are one or more little pins 90 that are movable in radial direction from the cylinder 92 so as to protrude from it or not. On the base of the central cylindrical body 94 opposite to the abutment 98 there is mounted a shank 96 axially slidable inside the central cylindrical body 94. The pins 90 are pushed outwardly the cylinder 92 e.g. by a spring inside the cylinder 92. Depending on the position of the shank 96 (e.g. it is held in a rest position by an inner spring) the pins 90 are locked in position or are free to re-enter inside the cylinder 92; or the pins 90 are connected to the shank 96 so that they are translated according to the position of the shank 96. In the drive 60 there is a pressing means for pressing or releasing or pulling the shank 96 according to the following logic: when a tool U is threaded by the pins 68, the shank 96 is brought or held in the position that leaves the pins 90 free to translate, so that they can re-enter into the cylinder 92 and the tool U can slide over the cylinder 92 until it meets the abutment 98. When the tool is engaged, the pressing means controls the shank 96 and brings it to the position wherein the pins 90 remain fixed, to avoid the detachment of the tool U from the cylinder 92. To dismount the tool U from the cylinder 92 the pressing means controls the shank 96 and brings it back to the position wherein the pins 90 can re-enter. In fig. 12, with dashed lines S there is indicated as an example the thickness of a tool hooked onto the pin 68.

OPERATION

To bring a particular tool U from the storage unit MC to one of the tables TS, TD, an electronic control unit or a programmed microprocessor (not shown) commands the motor 18 and moves the table 14 until the frame 30 containing that tool U is brought between the columns 12, aligning the guide 50 with the guide 52, i.e. by carrying the selected frame in the reference position for lifting. At the same time, the protruding element 56 of that frame 30 has also moved, bringing itself on the flange 44.

That frame 30 is raised by actuating the screw 40 and lifting the block 42, which raises the frame 30 by lifting the element 46 (for greater stability each column has a block 42 and each side of a frame 30 is provided with a protruding element 46 so that a frame 30 is lifted by pulling it upwards on two opposing sides).

The electronic control unit or the microprocessor calculates the lifting level of the frame 30 necessary to align to the table TD, TS the row of tools where the desired tool is. Specifically, the guide 32 that holds the desired tool U is aligned with the corresponding guide on the table TS, TD and with the segment 70, which in the meantime has been lifted under the guide 64.

At this point, the trolley 62 slides on the guide 64 to move in front of the desired tool U, and the head 66 moves the pins 68 to engage the tool U. Such tool is then translated onto the destination table TU, TD by sliding the trolley 62 from the guide 64 on the guide G, up to the mounting point of the tool.

By doing the preceding steps in reverse, one can withdraw a tool from the press P and store it into the storage unit MC.