Patent Description:
Typically, the upper table will couple with male forming tools, such as press brake and punch tools, and the bottom table will couple with female forming tools, such as dies. In order to perform a variety of forming operations, differently shaped press brake tools and dies are used. Thus, it is often necessary to exchange various forming tools within both the upper table and lower table.

Because the forming tools mounted in the lower table are supported from below, they may be substituted with relative ease. The forming tools mounted to the upper table, however, are suspended from above, usually held in place by a clamping mechanism that clamps all of the forming tools simultaneously. Upon loosening, unlocking, or releasing the clamping mechanism, the forming tools mounted to the upper table may be removed by sliding the tools horizontally to an open end of the upper table, or in some instances, by removing the tools vertically. Horizontal exchange of the forming tools can be cumbersome due to the proximity of the forming tools with respect to one another in the upper table, often necessitating the removal of each tool mounted within the upper table when only one tool is being exchanged. Neighboring clamps may also interfere with horizontal removal of the tools.

Vertical removal and insertion of the forming tools may not improve the exchange process due to the safety risks associated with handling the often heavy forming tools. In particular, loosening the clamping mechanism of the upper table may result in one or more tools falling and injuring a press brake operator.

To prevent the forming tools from accidentally falling from the upper table of a press brake assembly, several safety mechanisms have been developed. One such mechanism may involve a safety tang that protrudes laterally from a surface of the forming tool. Such a safety tang may be shifted into a complementary groove defined by a tool holder in the upper table, thereby securing the tool to the holder until the tool is clamped. This mechanism is problematic, however, because of the manipulation required of the user to actuate the safety mechanism and secure the tool within the holder. Other preexisting safety mechanisms that involve forming tools equipped with a variety of latches, straps, or projections and complementary receiving spaces defined by tool holders are deficient for similar reasons. These designs typically employ a variety of movable external parts and often require a high degree of structural specificity between the design of each forming tool and corresponding tool holder.

Thus, there exists a need for improved mechanisms used to secure forming tools to the upper table of a press brake assembly while the clamping mechanism of such an assembly is disengaged, such that heavy forming tools can be quickly exchanged without the risk of accidentally falling.

<CIT> discloses the features of the first part of the independent claims. Further prior art is known from <CIT> and <CIT>.

The invention is determined by the independent claims.

A tool includes a magnetic safety mechanism for operation in a press brake or similar machine apparatus. The mechanism includes a coupling assembly configured to provide a releasable magnetic coupling between the tool and a tool holder. A release is provided to selectively engage and disengage the magnetic coupling with the tool holder, alternately coupling and releasing the tool from the press assembly.

A punch for a folding press or press brake, with a top protrusion or tang that fits into a cavity in said press brake's upper tool holder, with a safety mechanism for temporarily holding said punch in said press brake using a switchable or adjustable permanent magnet assembly to urge or retain the punch upward into a holder receiving cavity for placement or staging until said holder is activated, thus clamping said punch solidly in place for use, the punch thus having a locked position where said punch is safely restrained in said punch holder, or an unlocked setting, where said punch can be manually installed in or removed from said punch holder.

The safety mechanism, where an assembly of permanent magnets and ferromagnetic parts are arranged to work cooperatively in a magnetic circuit, with some magnet(s) or part(s) made to be selectively moveable such that said magnetic circuit can be debilitated or weakened (as for punch installation or removal) or alternatively positioned so as to be optimized or enabled, to facilitate secure retention of punch in the holder until said holder is activated to clamp said punch solidly in the holder for folding operation.

The safety mechanism, where the magnetic assembly includes one or more electromagnets which could be switchable to selectively aid or conflict with the magnetic circuit, to effect retention or release of said punch. The safety mechanism, where the magnetic assemblies consist of two or more parallel circuits of combinations of magnets and ferromagnetic parts such that one switchable or adjustable assembly is thus scalable for higher magnetic forces to compensation. The safety mechanism, provided with a mechanism for directly leveraging or prying the punch away from the holder.

The safety mechanism, where one or more magnetic assemblies or permanent magnets are arranged along the length of a punch. The safety mechanism, where such magnetic assembly or assemblies employs a bi-stable or non-momentary locked and unlocked state. The safety mechanism, where the selectively moveable part or parts move slidably. The safety mechanism, where the selectively moveable part or parts move rotatably.

A safety mechanism for holding a punch in a folding press or press brake using a permanent magnet assembly or permanent magnet or array of magnets to urge or retain the punch upward into a holder receiving cavity for placement or staging until said holder is activated to grip said punch solidly in place for use, such non-adjustable magnetic assembly being practical for smaller punches, where the forces encountered would be low enough that said punches could be manually installed or removed to or from said holder without further mechanical adjustment or rearrangement of the magnetic circuit.

The safety mechanism, provided with a mechanism for directly leveraging or prying the punch away from the holder. The safety mechanism, where the magnets or magnetic assemblies are held in place with set-screws, glue, spring-pins, or such as are obvious variations of methods for securing said magnets or magnetic assemblies to the punch. The safety mechanism, where the magnet or magnets are installed in the punch shoulder or tang with additionally assembly features.

A safety mechanism for holding a punch in a Folding Press or Press Brake using a permanent magnet assembly to urge the punch upward into a holder receiving cavity for placement or staging until said holder clamps said punch solidly in place for use, with non-adjustable magnets but with a mechanism for debilitating the magnetic circuit via an increasing gap or gaps in said magnetic circuit by leveraging or prying apart some part(s) within said magnetic circuit.

The safety mechanism, with a selectable mechanism for dissipating magnetic flux away from the productive magnetic circuit by introducing a magnet or magnets or ferromagnetic part or parts to diverge some of the flux away from assisting in the punch-holding work of the magnetic circuit thus providing a selectably locked and unlocked state.

A press brake tool comprising: a tool body having a working end configured for operation on a workpiece and a coupling end configured for selective engagement with a tool holder, the working end disposed generally opposite the coupling end; a magnetic assembly comprising one or more magnetic elements configured to generate a magnetic flux coupling adapted for the selective engagement of the coupling end of the tool body with the tool holder; and a coupling mechanism configured to manipulate at least one of the magnetic elements to modulate a strength of the magnetic flux coupling, where the coupling mechanism is adapted for selective disengagement of the coupling end of the tool body from the tool holder.

The press brake tool, further comprising a tang formed on the coupling end of the tool body and adapted for the selective engagement with the tool holder, where the magnetic assembly is configured to generate the magnetic flux coupling between the tang and a magnetic component of the tool holder. The press brake tool, where the magnetic assembly comprises one or more permanent magnets disposed in the tang and configured to generate the magnetic flux coupling with the tool holder through one or both of a top surface and a side surface of the tang. The press brake tool, where the coupling mechanism comprise a magnetic armature configured to modulate the strength of the magnetic flux coupling by relative motion with respect to the one or more permanent magnets. The press brake tool, where the relative motion comprises transverse location of the armature with respect to the one or more permanent magnets. The press brake tool, further comprising a pushbutton type biasing member configured to retain the armature in alternate locked and unlocked positions, where the coupling end of the tool body is selectively engaged with and disengaged from the tool holder, respectively.

The press brake tool, where the relative motion comprises rotation of the magnetic armature with respect to the one or more permanent magnets. The press brake tool, further comprising gear member configured for rotation of the armature between alternate locked and positions, where the coupling end of the tool body is selectively engaged with and disengaged from the tool holder, respectively. The press brake tool, further comprising a pushbutton coupled to the gear member via a rack and pinion assembly and adapted for rotation of the armature thereby.

The press brake tool, further comprising a lever coupled to the armature for rotation thereof. The press brake tool, where the armature comprises transversely oriented magnetic elements configured for selective interaction with corresponding transversely oriented permanent magnets in the tang. The press brake tool, where the transversely permanent magnetics in the tang are adapted to generate the magnetic flux coupling through top surface and the side surface of the tang, respectively.

A machine tool comprising: a first end configured for operation on a workpiece; a second end configured for engagement with a tool holder; a plurality of magnetic elements configured to generate magnetic flux couplings adapted for the engagement of the second end of the tool body with the tool holder; and a coupling mechanism configured to modulate the magnetic flux couplings, where the second end of the tool body is selectively disengaged from the tool holder.

The machine tool, where the coupling mechanism comprises first and second magnetic armatures joined together by a transverse member. The machine tool, where first and second magnetic armatures have transversely oriented magnetic components. The machine tool, where the first and second magnetic armatures are configured for modulating the magnetic flux coupling by selective interaction with different respective permanent magnet elements disposed in the second end of the machine tool. The machine tool, where the different permanent magnet elements are disposed to generate the magnetic flux coupling through a top surface and one or more side surfaces of the second end of the machine tool, respectively.

The machine tool, further comprising a magnetically permeable material disposed adjacent at least one of the magnetic elements and adapted to substantially magnetically isolate the at least one elements from others of the magnetic elements. The machine tool, where the magnetically permeable material is disposed adjacent a first set of the
magnetic elements disposed to generate a first component of the magnetic flux couplings through a top surface of the second end of the machine tool, substantially isolated from a second set of the magnetic elements disposed to generate a second component of the magnetic flux couplings through at least one side surface of the second end of the machine tool. The machine tool, further comprising one or more magnetic gaps disposed adjacent at least one of the plurality of magnetic elements, the magnetic gaps adapted to modulate at least one of the magnetic flux couplings by manipulation of the coupling mechanism with respect thereto.

Suitable press brake tool systems can include a tool body having a working end configured for operation on a workpiece and a coupling end configured for selective engagement with a tool holder, the working end spaced from the coupling end along the tool body; and one or more magnetic elements configured to induce a magnetic coupling between the tool body and the tool holder, where the coupling end of the tool body is magnetically engageable with the tool holder.

The magnetic elements can include one or more magnets disposed in the tool body for generating magnetic flux to induce the magnetic coupling, one or more ferromagnetic elements disposed in the tool body for guiding magnetic flux to induce the magnetic coupling, or a combination thereof. The magnetic coupling can be sufficient to support a weight of the tool body upon engagement of the coupling end with the tool holder.

The press brake tool systems include a mechanism configured for selective disengagement of the coupling end of the tool body from the tool holder. The mechanism comprises an actuator engaged with the tool body, the actuator configured to urge at least a portion of the coupling end from the tool holder to define an air gap therebetween.

The mechanism can comprise a pry bar or lever member engaged with the tool body, the pry bar or lever member extending from a first end to a second end, the second end configured to selectively disengage the coupling end of the tool body from the tool holder upon actuation of the first end. The first end of the pry bar or lever member may be accessible by a user, e.g., with the coupling end of the tool body engaged in the tool holder, and where the second end of the pry bar or lever member is configured to protrude from the tool body to selectively disengage the coupling end of the tool body from the tool holder upon manipulation of the first end by the user. A biasing element can be configured to bias the second end of the pry bar or lever member in a position disposed within the tool body, absent manipulation of the first end.

A load-bearing shoulder can be configured to bear a mechanical load between the tool holder and the tool body upon operation of the working end, where the second end of the pry bar or lever member is configured to protrude from the load-bearing shoulder to selectively disengage the coupling end from the tool holder. A pin or hinge element can be disposed between the first end of the pry bar or lever member and second end of the pry bar or lever member, e.g., where the pry bar or lever member is pivotably engaged with the tool body by the pin or hinge element. In some examples, the pry bar or lever member comprises a longitudinal portion extending from the first end to the pin or hinge element and a transverse portion extending transversely from the longitudinal portion, e.g., between the pin or hinge element and the second end.

The mechanism can comprise a longitudinal shaft or pin member engaged with the tool body, the longitudinal shaft or pin member extending from a first end configured for actuation by a user to a second end configured to selectively disengage the coupling end of the tool body from the tool holder upon actuation of the first end. The longitudinal shaft or pin member may be disposed in sliding engagement with the tool body, e.g., with the second end configured to extend from the tool body to selectively disengage the coupling end from the tool holder upon actuation of the first end.

The mechanism can comprise an armature having one or more magnets or ferromagnetic components configured to modulate a strength of the magnetic coupling by motion with respect to a flux path defined by disposition of the one or more magnetic elements in the tool body. The armature may be configured to rotate the one or more magnets or ferromagnetic components with respect to the flux path, or with respect to the poles of the magnetic elements defining the flux path. The armature may be configured for lateral motion of the one or more magnets or ferromagnetic components with respect to the flux path defined by magnetic assembly. A lever, knob or push button actuator can be engaged with the tool body, and mechanically coupled to the magnetic armature for manipulation of the one or more magnets or ferromagnetic components by the user to modulate the strength of the magnetic coupling. The mechanism may also comprise a plurality of armature members, each having one or more of the magnets or ferromagnetic components configured to modulate the strength of the magnetic coupling by rotational or lateral motion with respect to one or more flux paths defined by disposition of the one or more magnetic elements in the tool body.

The magnetic elements may comprise one or more permanent magnets disposed in the tool body, the one or more permanent magnets configured to form the magnetic coupling between the tool body and the tool holder with the coupling end of the tool body engaged therein. One or more non-ferromagnetic elements may be disposed in the tool body and adapted for modulation of a flux path through the one or more magnetic elements, e.g., where the strength of the magnetic coupling is responsive to the modulation of the flux path.

The one or more magnetic elements may comprise a plurality of magnetic sub-assemblies. Each magnetic sub-assembly may comprise one or more magnets or ferromagnetic elements configured to independently induce a magnetic coupling between the coupling end of the tool body and the tool holder.

A tang can be defined by the coupling end of the tool body, and adapted for the selective engagement with the tool holder. One or more magnets or ferromagnetic elements may be disposed in the tang, and configured to induce the magnetic coupling by generating or guiding magnetic flux between the tang and the tool holder.

A load-bearing shoulder can be defined on the tool body, and configured to bear a mechanical load between the tool holder and the tool body for operation of the working end of the tool body on a workpiece. One or more magnets or ferromagnetic elements may be disposed in the load-bearing shoulder, and configured to induce the magnetic coupling by generating or guiding magnetic flux between the load-bearing shoulder and the tool holder.

Suitable methods of use and operation include disposing a tool body with respect to a tool holder, the tool body having a working end configured for operation on a workpiece, a coupling end spaced from the working end along the tool body, and one or more magnetic elements configured to induce a magnetic coupling; and engaging the working end of tool body with the tool holder, where the magnetic coupling is induced between the tool body and the tool holder. The magnetic elements may comprise one or more permanent magnets disposed in the tool body for generating magnetic flux to induce the magnetic coupling, one or more ferromagnetic elements disposed in the tool body for guiding magnetic flux to induce the magnetic coupling, or a combination
thereof. The magnetic flux coupling may be sufficient to support a weight of the tool body upon engagement of the coupling end with the tool holder.

An actuator mechanism may be engaged with the tool body, and operated to selectively disengage the coupling end of the tool body from the tool holder. Operating the actuator mechanism may comprise manipulating a knob, lever or pushbutton device coupled to the tool body, and mechanically engaged with a shaft or lever member configured to urge at least a portion of the coupling end of the tool body from the tool holder to define an air gap therebetween.

Operating the actuator mechanism may comprise manipulating a pry bar or lever pivotally engaged with the tool body, the pry bar or lever configured to selectively disengage at least a portion of the coupling end of the tool body from the tool holder. Operating the actuator mechanism may also comprise accessing a first end of a lever or pry member engaged with the tool body, where the coupling end of the tool body is engaged in the tool holder; and manipulating the first end of the lever or pry member such that a second end of the lever or pry member protrudes from the tool body to selectively disengage the coupling end from the tool holder.

Upon releasing the first end of the lever or pry member, the second end may be biased into a position disposed within the tool body. The second end of the lever or pry member may protrude from a load-bearing shoulder of the tool body upon manipulation of the first end, the load-bearing shoulder configured to bear a mechanical load between the tool holder and the tool body upon operation of the working end.

Operating the actuator mechanism can comprise manipulating a longitudinal shaft in sliding engagement with the tool body. The longitudinal shaft can be configured for urging the coupling end of the tool body from the tool holder, e.g., when manipulated by a user.

Operating the actuator mechanism can comprise manipulating one or more magnetic armatures with respect to a flux path defined by disposition of the one or more magnetic elements in the tool body. Manipulating the one or more magnetic armatures may comprise rotation or lateral motion of one or more magnets or ferromagnetic components with respect to the flux path, or with respect to the poles of the magnetic elements defining the flux path. A lever, knob or push button actuator can be
manipulated, e.g., by a user, to provide rotation or lateral motion of the one or more magnetic armatures with respect to the flux path.

Suitable methods include selectively engaging a tang on the coupling end of the tool body with the tool holder, where the magnetic coupling is induced by one or more of the magnetic elements disposed in the tang. Additional methods include selectively engaging a load-bearing shoulder defined on the tool body with the tool holder, where the magnetic coupling is induced by one or more of the magnetic elements disposed in the load-bearing shoulder.

A press brake tool system includes a tool body having a working end configured for operation on a workpiece and a coupling end configured for selective engagement with a tool holder; a magnetic assembly configured to induce a magnetic coupling between the coupling end of the tool body and the tool holder; and a mechanism configured for selective disengagement of the magnetic coupling. The magnetic assembly may comprise one or more magnets disposed in the tool body for generating magnetic flux to induce the magnetic coupling, one or more ferromagnetic elements disposed in the tool body for guiding magnetic flux to induce the magnetic coupling, or a combination thereof. The magnetic coupling may be sufficient to support a weight of the tool body upon engagement of the coupling end with the tool holder.

The mechanism can comprise a pry bar or lever actuator engaged with the tool body, the pry bar or lever actuator configured to urge at least a portion of the coupling end from the tool holder to define an air gap therebetween. The pry bar or lever actuator may comprise a first end accessible by a user and a second end configured to extend from the tool body to selectively disengage the coupling end from the tool holder upon manipulation of the first end by the user.

The pry bar or lever actuator may comprise a longitudinal portion extending from a first end and a transverse portion extending transversely from the longitudinal portion to the second end. A pin or hinge may pivotably engage the pry bar or lever actuator with the tool body. A biasing element may bias the second end of the pry bar or lever actuator within the tool body, absent manipulation of the first end.

A load-bearing shoulder can be configured to bear a mechanical load between the tool holder and the tool body upon operation of the working end. The second end of the pry bar or lever member may protrude from the load-bearing shoulder to selectively disengage the coupling end from the tool holder.

The mechanism can comprise a longitudinal shaft or pin member disposed in sliding engagement with the tool body, and configured for actuation by a user to selectively disengage the coupling end of the tool body from the tool holder. The longitudinal shaft or pin member may comprise a first end mechanically engaged with an actuator and a second end configured to extend from the tool body to selectively disengage the coupling end from the tool holder upon manipulation of the actuator.

The mechanism can comprise one or more magnetic armatures configured to modulate a strength of the magnetic coupling by motion with respect to a flux path defined by the magnetic assembly. The one or more magnetic armatures may each comprise one or more magnets or ferromagnetic components configured for rotation or lateral motion with respect to the flux path, or with respect to the magnetic elements defining the flux path. An actuator may be engaged with the tool body, and mechanically coupled to the one or more magnetic armatures for manipulation of the magnets or ferromagnetic components by a user to modulate the strength of the magnetic coupling.

The magnetic assembly can comprise two or more magnetic subassemblies. The subassemblies may be configured to independently induce two or more respective magnetic couplings between the coupling end of the tool body and the tool holder.

A tang may be defined by the coupling end of the tool body and adapted for the selective engagement with the tool holder, e.g., where the magnetic assembly comprises one or more magnets or ferromagnetic elements disposed in the tang to induce the magnetic coupling between the tang and the tool holder. A load-bearing shoulder may be defined on the tool body to bear a mechanical load between the tool holder and the tool body upon operation of the working end, e.g., where the magnetic assembly comprises one or more magnets or ferromagnetic elements disposed in the load-bearing shoulder to induce the magnetic coupling between the load-bearing shoulder and the tool holder.

<FIG> is an isometric view of a tool component <NUM> for a press brake machine or similar press-type machine apparatus. While generally described as a press brake tool herein, component <NUM> may alternately be configured as a press brake punch, punch tool, or similar machine tool component.

As shown in <FIG>, tool <NUM> includes a tool end or working end <NUM> opposite a coupling end or tang <NUM>. Depending on the particular configuration of tool <NUM>, working end <NUM> may be generally positioned beneath coupling end or tang <NUM>, such that working end <NUM> is the bottom end and coupling end or tang <NUM> is the top end. Tang <NUM> may be mounted within a corresponding tool holder as part of a press brake assembly. In operation, such a press brake assembly may punch, impress, crimp, fold, crease, or otherwise shape various workpieces inserted beneath working end <NUM> and optionally one or more forming dies. In some examples, a workpiece may include a sheet metal component or other material to be tooled.

In these examples, tool <NUM> may include two load-bearing shoulder portions <NUM>, <NUM> that extend horizontally outward from reference faces <NUM>, <NUM> at the base of tang <NUM>. Shoulder portions <NUM>, <NUM> may contact complementary surfaces on a tool holder upon inserting tool <NUM> within the holder, in order to bear or transfer a load between the tool holder and the tool body upon operation of the working end on a sheet metal component or other workpiece.

Tool <NUM> also includes a plurality of magnetic assemblies <NUM> vertically disposed within tang <NUM> and tool body <NUM>. Each magnetic assembly <NUM> may include one or more magnetic elements, which may include one or more permanent magnets, ferromagnetic components, or combinations thereof. As illustrated, each magnetic assembly <NUM> may be partially exposed through a top surface <NUM> of tang <NUM>. In this particular example, tool <NUM> includes three magnetic assemblies <NUM>. In other examples, the number of magnetic assemblies <NUM> in a given tool <NUM> may vary, ranging from <NUM> to about <NUM> magnetic assemblies <NUM>. Each magnetic assembly <NUM> may be removable, adjustable, or fixed within tool <NUM>.

The body <NUM> of tool <NUM> may include front and back surfaces <NUM> and <NUM>. In examples, surfaces <NUM>, <NUM> may be variously shaped and sized depending on the desired function of tool <NUM>. Tool <NUM> may further define a lateral cavity <NUM>, of which only the opening is visible in <FIG>. Lateral cavity <NUM> may be configured to slidably receive an armature <NUM>, which is shown fully inserted within the lateral cavity in <FIG>. In the embodiment shown, armature <NUM> provides a coupling mechanism configured to modulate the strength of a magnetic flux coupling induced between tool <NUM> and the holder. In some examples, armature <NUM> can be adapted for selective disengagement of the coupling end or tang <NUM> of tool <NUM> from the holder. Armature <NUM> contains one or more dynamic or moving elements, which can include one or more magnetic elements, e.g., permanent magnets and/or ferromagnetic components.

Once inserted into the receiving space defined by a tool holder, tool <NUM> may be held in place at least temporarily by magnetic forces prior to clamping tool <NUM> with the holder. In particular, the magnetic elements of magnetic assemblies <NUM> and armature <NUM> may align such as to guide a magnetic flux in a circuit further involving a ferromagnetic material, e.g., medium alloy steel, comprising the tool holder. The magnetic flux can urge tool <NUM> upwardly into the tool holder so as to minimize non-ferromagnetic gaps, e.g., air gaps, between the two components, thus holding tool <NUM> up against the load- impinging shoulder surfaces of the holder. In some examples, the magnetic flux coupling induced between tool <NUM> and its tool holder can support the weight of the tool without additional clamping support. By holding tool <NUM> in place prior to clamping a tool holder around the upper portion of tool <NUM>, a user's hands may be free to install additional tools until the holder is activated to lock all tools in place for operation on a workpiece. In some embodiments, the strength of the magnetic flux coupling can secure tool <NUM> even during operation on a workpiece without additional clamping support.

IB is a front view of tool <NUM>. As illustrated in FIG. IB, magnetic assemblies <NUM> may protrude a distance above top surface <NUM>. The distance by which magnetic assemblies <NUM> protrude above top surface <NUM> may vary.

Press brake tool system or apparatus <NUM> includes a tool body <NUM> with a working end configured for operation on a workpiece, and a coupling end configured for selective engagement with a tool holder. The working end is spaced from the coupling end along the tool body, e.g. at opposite top and bottom ends. One or more magnetic assemblies <NUM> can be configured to induce a magnetic coupling between the tool body <NUM> and the tool holder, where the coupling end of the tool body is magnetically engageable with the tool holder.

The magnetic assemblies <NUM> can include one or more magnets disposed in the tool body <NUM> for generating magnetic flux to induce the magnetic coupling, one or more ferromagnetic components disposed in the tool body <NUM> for guiding magnetic flux to induce the magnetic coupling, or a combination thereof. Typically, the magnetic coupling is sufficient to support the weight of the tool body <NUM> upon engagement of the coupling end with the tool holder.

<FIG> is a top view of tool <NUM>, showing each of the three magnetic assemblies <NUM> included in this particular example. In other examples, the number, spacing, and arrangement of magnetic assemblies <NUM> within tool <NUM> may vary. As shown in <FIG>, each magnetic assembly <NUM> may include two assembly slugs <NUM> laterally flanking each side of an end guide <NUM>. Assembly slugs <NUM> and end guide <NUM>, along with other components of each magnetic assembly <NUM>, may be contained within a housing <NUM>, which can be fixed within tool <NUM>. In some examples, such components may be cast or mold into housing <NUM> to form each magnetic assembly <NUM>. Housing <NUM> may be a structural insert that defines the external shape of each magnetic assembly <NUM> and its internal
compartments. Such an insert may be made from various materials including but not limited to one or more plastics or polymer compositions.

In embodiments, the number of assembly slugs <NUM> and end guides <NUM> may vary. Each assembly slug <NUM> may be made from various materials including but not limited to a magnetically permeable material, e.g., one or more metals such as steel. In some examples, such magnetically permeable material may be highly permeable. End guides <NUM> may also be made from various materials including but not limited to iron or steel, e.g., electrical steel. <FIG> also shows line A-A, which denotes a cross-sectional plane used for illustration purposes.

ID is an alternate top view of tool <NUM>, showing three magnetic assemblies <NUM> exposed at one end through top surface <NUM>. ID also shows line B-B, which denotes a cross-sectional plane, and detail K, used for illustration purposes.

The magnetic assemblies <NUM> can include one or more permanent magnets disposed in the tool body <NUM>, and configured to form a magnetic coupling between the tool body and the tool holder with the coupling end of the tool body <NUM> is engaged. One or more non-ferromagnetic components can also be disposed in the tool body, and adapted for modulation of a flux path through the one or more magnetic elements (e.g., where the strength of the magnetic coupling is responsive to the modulation of the flux path). Similarly, a plurality of magnetic sub-assemblies <NUM> may each include one or more magnets, ferromagnetic elements or non-ferromagnetic components configured to independently induce a magnetic coupling between the coupling end of the tool body <NUM> and the tool holder.

A tang <NUM> can be defined by the coupling end of the tool body, and adapted for the selective engagement with the tool holder. One or more magnets or ferromagnetic components can be disposed in the tang <NUM>, and configured to induce the magnetic coupling by generating or guiding magnetic flux between the tang <NUM> and the tool holder.

One or more load-bearing shoulders <NUM>, <NUM> can be defined on the tool body, and configured to bear a mechanical load between the tool holder and the tool body for operation of the working end of the tool body <NUM> on a workpiece. One or more magnets or ferromagnetic components can also be disposed in the load-bearing shoulder <NUM>, <NUM>, and configured to induce the magnetic coupling by generating or guiding magnetic flux between the load-bearing shoulder <NUM>, <NUM> and the tool holder.

IE is a section view of tool <NUM>, taken along line A-A of <FIG>. This section view illustrates the inner portion of a magnetic assembly <NUM> and armature <NUM> inserted therethrough, each component positioned within tool <NUM>. As shown in this particular view, magnetic assembly <NUM> can include an assembly magnet <NUM>, multiple end guides <NUM> and a return flux guide or loop component <NUM>, each contained within housing <NUM>. Armature <NUM> can include an armature magnet <NUM>. IE also shows an outline of the bottom portion of an exemplary tool holder TH (dashed lines) with which tool <NUM> is magnetically coupled and clamped into a press brake machine or similar machine apparatus. In various embodiments, tool holder TH can be a preexisting, conventional tool holder lacking discrete magnetic components and made of steel, for example.

In some examples, assembly magnet <NUM> may comprise a permanent magnet made from one or more magnetic materials, e.g., neodymium iron boron ("NdFeB"). Assembly magnet <NUM> may be a bar magnet.

In the particular configuration of FIG. IE, armature magnet <NUM> is included within armature <NUM> and positioned beneath assembly magnet <NUM> when armature <NUM> is inserted within lateral cavity <NUM>. Like assembly magnet <NUM>, armature magnet <NUM> may also be a permanent magnet made of NdFeB. In some embodiments, armature magnet <NUM> may be made of other magnetic materials. Armature magnet <NUM> may be magnetized diametrically and oriented such that the north pole of armature magnet <NUM> is in closest proximity to the south pole of assembly magnet <NUM>.

In the example of FIG. IE, end guides <NUM> are positioned above assembly magnet <NUM>, and between assembly magnet <NUM> and armature magnet <NUM>. In some examples, end guides <NUM> may be made from various materials including but not limited to one or more metals, e.g., iron or electrical steel.

Return flux guide <NUM> is positioned beneath armature magnet <NUM> in this example, and is also contained within housing <NUM> as a sub-component of magnetic assembly <NUM>. Return flux guide <NUM> may comprise a magnetically permeable material. In some examples, such material may be highly permeable.

In the example depicted in FIG. IE, magnetic assembly <NUM> extends downward through tang <NUM> and into a vertical cavity <NUM> defined by tool body <NUM> to a distance below the horizontal plane of shoulders <NUM>, <NUM>. The distance by which each vertical magnetic assembly <NUM> extends within tool <NUM> may vary and may depend on the shape, weight,
and/or size of tool <NUM>, the number of magnetic assemblies <NUM> included within a given tool <NUM>, and/or the configuration of the tool holder into which tool <NUM> is inserted. As further shown, an air gap <NUM> may be defined beneath the bottom-most surface of flux guide <NUM> in magnetic assembly <NUM>, at the bottom of vertical cavity <NUM>. In these examples, gap <NUM> may contribute to a desired magnetic flux direction induced by tool <NUM> and the holder by providing a non-ferromagnetic component positioned to modulate the magnetic flux coupling, e.g., by guiding the magnetic flux or by modifying or disrupting the flux path.

IF is a top view of a vertical magnetic assembly <NUM>, taken at detail K in FIG. Detail K illustrates a magnified view of the top of each magnetic assembly <NUM>. IF, each magnetic assembly may include two D-shaped assembly slugs <NUM> and an end guide <NUM> exposed at top surface <NUM>. Housing <NUM>, also visible at top surface <NUM>, may laterally partition assembly slugs <NUM> and end guide <NUM>.

<FIG> is a section view of detail H taken along section A-A. As shown in <FIG>, assembly magnet <NUM> may define an approximately rectangular cross-sectional shape, and armature magnet <NUM> may define an approximately circular cross-sectional shape. In other examples, the shape of each magnet may vary. The cross-sectional width of each wall of housing <NUM> may also vary. In this particular embodiment, the cross-sectional width of each exterior wall of housing <NUM> may be the greatest near top surface <NUM>.

<FIG> is an exploded view of a magnetic assembly <NUM> and armature <NUM>. In this example, magnetic assembly <NUM> defines an aperture <NUM> configured to slidably receive armature <NUM> such that magnetic assembly <NUM> and armature <NUM> intersect. As shown, aperture <NUM> may define a lateral through-hole. Aperture <NUM> may align with lateral cavity <NUM> of tool <NUM>, such that armature <NUM> is configured to slide seamlessly through aperture <NUM> and tool <NUM>.

As further shown in <FIG>, the sub-assemblies of magnetic assembly <NUM> and armature <NUM> may include numerous distinct components. In particular, assembly magnet <NUM>, return flux guide <NUM>, each end guide <NUM>, and each assembly slug <NUM> may be separate sub-components of each magnetic assembly <NUM>, arranged to generate a magnetic circuit upon assembly with armature <NUM> and insertion within a tool holder. Housing <NUM> may define one or more internal compartments for containing each of the internal components of magnetic assembly <NUM>. In this embodiment, housing <NUM> is cylindrical, but the shape of housing <NUM> may vary in other examples.

Each armature <NUM> can include a plurality of dynamic elements, such as armature magnets <NUM>, which can be permanent magnets in various embodiments. In this particular example, armature <NUM> includes three armature magnets <NUM> each flanked by a pair of D-shaped armature slugs <NUM>. The armature slugs <NUM> can comprise ferromagnetic wedges. When inserted within tool <NUM>, armature magnets <NUM> and slugs <NUM> can align with the magnetic elements included within each magnetic assembly <NUM>. In embodiments, armature <NUM> can include one or more permanent magnets, electromagnets, ferromagnetic components, and/or non-ferromagnetic components collectively arranged to strengthen or support a magnetic circuit between tool <NUM> and the holder. Armature <NUM> may further include an end portion <NUM> that may be manually engaged by a user of tool <NUM> to insert and remove armature <NUM> therefrom. In some examples, end portion <NUM> may comprise a handle, knob, protrusion, or other feature graspable by a user.

<FIG> is a section view of tool <NUM>, taken along line B-B of FIG. In this example, tool <NUM> may define an internal lateral cavity <NUM> configured to slidably receive armature <NUM>. A bias member <NUM>, e.g., a spring, may be secured at a stop end <NUM> of cavity <NUM>, protruding laterally within cavity <NUM> such that armature <NUM> contacts bias member <NUM> upon insertion into cavity <NUM>. Cavity <NUM> may define a receiving end <NUM> positioned opposite stop end <NUM>. Receiving end <NUM> may define a greater cross-sectional height and/or width to accommodate armature end portion <NUM>.

As further shown in <FIG>, assembly slugs <NUM> may be laterally partitioned from each end guide <NUM>, assembly magnet <NUM>, armature magnet <NUM>, and flux guide <NUM> by housing <NUM>. An assembly slug <NUM> and armature slug <NUM>, in combination, may extend vertically from top surface <NUM> to the top plane of flux guide <NUM>.

Armature <NUM> may be inserted to various depths within cavity <NUM>. The depth at which armature <NUM> is inserted may determine whether tool <NUM> is in an engaged, locked position or a disengaged, unlocked position. In some examples, movement of armature <NUM> can switch the strength of the magnetic flux coupling between two bi-stable states: an engaged state in which the magnetic flux coupling between tool <NUM> and the holder is established, and a disengaged state in which the magnetic flux coupling between tool <NUM> and the holder is diminished or absent. <FIG> depicts the locked position, in which armature <NUM> contacts, but may not compress, bias member <NUM>. Accordingly, the locked position may represent a relaxed position. In this configuration, armature <NUM> functions as a button that can be manually pressed to various depths within cavity <NUM> by exerting various amounts of lateral force against armature end portion <NUM>. As shown in the locked position of <FIG>, armature end portion <NUM> is inserted within cavity <NUM> such that its end surface is flush with the end surface of tool <NUM>.

In the locked position, assembly magnet <NUM> included in each magnetic assembly <NUM> may be magnetically oriented the same as each armature magnet <NUM>. In these examples, each assembly magnet <NUM> is oriented such that its north pole is positioned above its south pole, and each armature magnet <NUM> is similarly oriented such that its north pole is oriented above its south pole. In this orientation, assembly magnet <NUM> armature magnet <NUM>, surrounded by the additional ferromagnetic components of tool <NUM> and its corresponding tool holder, may form a magnetic circuit that generates a magnetic flux <NUM> that passes vertically through each end guide <NUM>, loops through a ferromagnetic material comprising the tool holder when tool <NUM> is in the locked position within a receiving space defined by the holder. It may be desirable that magnetic circuit involves the shoulders of the tool holder: first to hold tool <NUM> firmly against such shoulders so that tool <NUM> is in an ideal position for clamping by a press brake or similar machine apparatus, and secondly because the gap between the tang <NUM> and the inside of the holder is designed as clearance and may therefore not be a precise or sufficiently small gap that it could be depended upon to form a reliable part of the magnetic circuit.

After passing through the tool holder, magnetic flux <NUM> may be guided back down into each assembly slug <NUM>, which, together with each armature slug <NUM>, may function as a ferromagnetic wedge that propagates magnetic flux <NUM> downward through each magnetic assembly <NUM>. At the bottom of each armature slug <NUM>, magnetic flux <NUM> may loop horizontally, via return flux guide <NUM>, and back upward through the south pole of armature magnet <NUM>.

As further shown in <FIG>, air gaps <NUM> and <NUM> may be present at the bottom of each vertical aperture <NUM> and receiving end <NUM>, respectively. Gaps <NUM> and <NUM> may function as non-ferromagnetic gaps to prevent magnetic flux <NUM> from dissipating within body <NUM> of tool <NUM> beneath vertical aperture <NUM> and receiving end <NUM>, thereby maintaining an upward flux direction.

<FIG> also shows that the body of armature <NUM> may be made from aluminum. In other examples, the body of armature <NUM> may be made from various different and/or additional materials. In this example, each flux guide <NUM> is made from a high permeability soft magnetic material. Other magnetic materials may also be suitable, depending upon flux density and other application-specific considerations.

<FIG> is a section view of tool <NUM> in an unlocked configuration, taken along line B-B of FIG. In the unlocked configuration, armature <NUM> may be urged a greater distance within lateral cavity <NUM>, thereby compressing bias member <NUM>. The magnetic poles of each assembly magnet <NUM> and armature magnet <NUM> are misaligned, creating a conflicting, and therefore much weaker, magnetic circuit. The reduced flux <NUM> generated within such a circuit may reduce the holding force between tool <NUM> and a corresponding tool holder, allowing manual insertion and removal of tool <NUM> with respect to the holder. In some examples, gravity alone may cause tool <NUM>, in the unlocked configuration, to fall from a corresponding tool holder.

The release mechanism can include any suitable armature <NUM> having one or more magnets or ferromagnetic components <NUM> configured to modulate a strength of the magnetic coupling by motion with respect to the flux path defined by disposition of the one or more magnetic elements <NUM> in the tool body. The armature <NUM> can rotate the magnets or ferromagnetic components <NUM> with respect to the flux path, or with respect to the poles of the magnetic elements <NUM> defining the flux path. The armature <NUM> can also be configured for lateral motion of the one or more magnets or ferromagnetic components <NUM> with respect to the magnetic elements <NUM> and the flux path defined by the magnetic elements <NUM>. A lever, knob or push button actuator can be engaged with the tool body <NUM>, and mechanically coupled to the magnetic armature <NUM> for manipulation of the magnets or ferromagnetic elements <NUM> by the user to modulate the strength of the magnetic coupling. The release mechanism may also comprise a plurality of armature members <NUM>, each having one or more of the magnets or ferromagnetic elements <NUM> configured to modulate the strength of the magnetic coupling by rotational or lateral motion with respect to one or more flux paths defined by disposition of the one or more magnetic elements <NUM> of the magnetic assembly <NUM> within the tool body <NUM>.

<FIG> is an isometric view of an upper portion of tool <NUM> for a press brake or similar machine apparatus. As shown in <FIG>, tool <NUM> may include a t-shaped magnetic circuit assembly with a sliding armature. The example of <FIG> includes two top magnets <NUM> included within tang <NUM>. A portion of each top magnet <NUM> may be exposed at the top surface <NUM> of tool <NUM>. Tool <NUM> further includes side magnets <NUM> within tang <NUM> , each exposed at reference face <NUM>.

Top and side magnets <NUM>, <NUM> can be fixed within tool <NUM>. Each top magnet <NUM> may be vertically oriented such that its north pole is positioned above its south pole. In some examples, top magnet <NUM> may be arranged in the opposite polar orientation. Each side magnet <NUM> may be oriented such that its north pole is positioned on the left side and its south pole on the right side, or vice versa. With respect to the magnetic orientation of top magnets <NUM>, side magnets <NUM> may thus be oriented in an opposing orientation. Regardless of the specific polar orientation, each side magnet <NUM> may include a magnetic pole facing the exterior of tool <NUM>, and a magnetic pole facing the interior of tool <NUM>. In any or all of the various examples included herein, the polar orientation of each magnet may be reversed, provided that the polarity of each magnet relative to the other magnets comprising the magnetic circuit remains the same.

Armature <NUM> can provide a coupling mechanism configured to modulate the strength of the magnetic flux coupling between tool <NUM> and the holder. Armature <NUM> is shown inserted within parallel lateral cavities defined by tool <NUM>. In particular, tool <NUM> includes two lateral cavities: an upper cavity <NUM> positioned above a lower cavity <NUM>. First or upper arm <NUM> of armature <NUM> may be slidably inserted into upper cavity <NUM>, and second arm <NUM> may be slidably inserted into lower cavity <NUM>. First arm <NUM> and second arm <NUM> may be connected at one end by a vertical or transverse armature member <NUM>. While the particular arrangement of upper cavity <NUM> and/or lower cavity <NUM> may vary, <FIG> illustrates that upper cavity <NUM> may be defined within tang <NUM>, and lower cavity <NUM> may be defined below the plane of shoulders <NUM>, <NUM> that demarcate the lower boundary of tang <NUM>. The exterior surface of transverse member <NUM> may remain accessible upon insertion of armature <NUM> within tool <NUM> such that transverse member <NUM> may be manually engaged by a user to insert armature <NUM> within tool <NUM>, and to adjust the lateral depth at which armature <NUM> extends into tool <NUM>. Upper arm <NUM> and lower arm <NUM> of armature <NUM> can each include one or more dynamic or moving elements, which may include permanent magnets and/or ferromagnetic components.

As further shown in <FIG>, a bias member <NUM> may be secured to a stop end <NUM> defined by lower cavity <NUM>. In this example, bias member <NUM> comprises a spring. In a locked or engaged configuration, bias member <NUM> may not be compressed, or may be only slightly compressed, by second arm <NUM> of armature <NUM>. Tool <NUM> also includes two vertical cavities <NUM>. In some examples, the number of vertical cavities may vary and may depend on the number of top magnets <NUM> needed to form a magnetic circuit with armature <NUM> strong enough to at least temporarily secure tool <NUM> within a tool holder.

Adjusting the position of armature <NUM> can modulate the strength of the magnetic flux coupling between tool <NUM> and the holder. For example, inserting armature <NUM> to a greater depth within tool <NUM> by compressing bias member <NUM> can cause misalignment between the magnetic poles of the dynamic elements of the armature and the magnetic poles of the top magnets <NUM> and side magnets <NUM>, thus disrupting the magnetic flux coupling between tool <NUM> and the holder and allowing for release of the tool. By contrast, when the magnetic elements included in armature <NUM> are magnetically aligned with top and side magnets <NUM>, <NUM> fixed within tool <NUM>, a magnetic circuit can be established, thereby inducing a magnetic flux guided from tang <NUM> through reference face <NUM> into a ferromagnetic shoulder portion of a tool holder coupled with tool <NUM>. Sliding armature <NUM> in this manner can gradually modulate the strength of the magnetic flux coupling between tool <NUM> and the holder.

<FIG> is an isometric section view of a tool <NUM> for a press brake or similar machine apparatus, taken along the length or longitudinal direction of tool <NUM>. Tool <NUM> may include a cross-shaped circuit assembly with a rotating armature. In the particular configuration of <FIG>, tool <NUM> includes two vertical magnetic assemblies <NUM> , each assembly <NUM> including a first magnet <NUM> and a second magnet <NUM>. First magnet <NUM> may be exposed at top surface <NUM>, positioned above a lateral cavity <NUM> defined by tool <NUM>. Second magnet <NUM> may be positioned below lateral cavity <NUM>. As further shown in the figure, focal wedges <NUM> may be sandwiched between each first magnet <NUM> and lateral cavity <NUM>, as well as between each second magnet <NUM> and lateral cavity <NUM>.

Tool <NUM> also includes a rotating armature <NUM><NUM>, which provides a coupling mechanism configured to modulate the strength of the magnetic flux coupling between tool <NUM> and the holder. By rotating, armature <NUM><NUM> may adjust the polar orientation of one or more dynamic elements, e.g., permanent disc magnets <NUM> and ferromagnetic collar <NUM><NUM>, contained in the armature and inserted within lateral cavity <NUM>. Rotating the dynamic elements of rotating armature <NUM> may gradually modulate the strength of the magnetic flux coupling along a spectrum from high strength to low or zero strength. This particular example includes two disc magnets <NUM> and one ferromagnetic collar <NUM>, but the number of dynamic magnetic components can vary depending upon tool size and application.

As further shown in <FIG>, tool <NUM> may also include an upper gear member <NUM>, which includes an elongate body <NUM> that extends through at least a portion of lateral cavity <NUM>. Upper gear member <NUM> may rotatably engage an adjacent pinion <NUM> via a plurality of complementary grooves, or mechanical teeth, protruding outward from the perimeter of both gear member <NUM> and pinion <NUM>. Together, pinion <NUM> and gear member <NUM> comprise gear assembly <NUM>. An idler gear <NUM> may be also positioned at the radial center of pinion <NUM>. Pinion <NUM> may rotatably engage rack <NUM> via a plurality of complementary grooves or mechanical teeth also protruding from rack <NUM>.

In operation, lateral movement of rack <NUM>, e.g., sliding, may drive rotation of armature <NUM>. Specifically, lateral movement of rack <NUM> may cause pinion <NUM> to rotate, thereby causing rotation of upper gear member <NUM>. Because body <NUM> of upper gear member <NUM> is secured within the radial center of each disc magnet <NUM>, rotation of body <NUM> also drives rotation of each disc magnet <NUM>, thereby adjusting the polarity of each disc magnet <NUM> with respect to first magnets <NUM> and second magnets <NUM>.

<FIG> is an isometric section view taken along the width of tool <NUM>, transverse to the view of <FIG>. As further detailed in <FIG>, tool <NUM> may include one or more side magnets <NUM>, <NUM>. A lateral focal wedge <NUM> may be sandwiched between each side magnet <NUM>, <NUM> and disc magnet <NUM>. In this particular example, disc magnet <NUM> is magnetized axially such that it includes four magnetic poles.

<FIG> is an isometric view of tool <NUM>. As shown in <FIG>, tool <NUM> may include an exterior button <NUM>. In this example, button <NUM> protrudes outward from front surface <NUM>, where it may be manually engaged by a user, for example. To rotate armature <NUM>, thereby either releasing or locking tool <NUM> within a corresponding tool holder, button <NUM> may be pushed. Pushing button <NUM> causes rack <NUM> to move laterally, thus causing pinion <NUM> and upper gear member <NUM> to rotate. Disc magnets <NUM> secured to gear member <NUM> may then be rotated, causing a shift in magnetic alignment within tool <NUM>.

<FIG> is a front view of tool <NUM>. As shown in <FIG>, each first magnet <NUM> may protrude above the plane defined by top surface <NUM>. Button <NUM> is positioned beneath tang <NUM>, within body <NUM> of tool <NUM>.

<FIG> is a top view of tool <NUM>. <FIG> is an alternate top view of tool <NUM>, showing section B-B.

As shown in <FIG> and <FIG>, a first set of magnets <NUM> may be exposed at top surface <NUM>. This particular embodiment includes two vertical magnetic assemblies <NUM>. In other examples, the number, size, and/or arrangement of magnetic assemblies <NUM> may vary. Button <NUM> is shown protruding laterally outward from tool <NUM>. <FIG> also shows line A-A, which denotes a cross-sectional plane used for illustration purposes.

<FIG> is a section view of detail H, taken along section A-A of <FIG>. With button <NUM> in a relaxed position, tool assembly <NUM> is in a locked or engaged configuration with respect to the tool holder. In the locked position, tool assembly <NUM> may form two magnetic circuits comprised of separate pathways of magnetic flux: flux pathway fi and flux pathway f<NUM>. As shown in <FIG>, flux pathway fi is guided in a counterclockwise direction through disc magnet <NUM> to first magnet <NUM>, through top surface <NUM> of tang <NUM> into a ferromagnetic portion of a tool holder TH, and back through one of side magnets <NUM>. The altemating magnetic poles of disc magnet <NUM>, top magnet <NUM>, and side magnet <NUM> in this configuration may generate the closed magnetic circuit defined by flux pathway f<NUM>.

Similarly, flux pathway f<NUM> is generated by the alternating magnetic poles of disc magnet <NUM>, side magnets <NUM>, and second magnet <NUM>. As shown in the figure, flux pathway f<NUM> may be guided in a clockwise direction, passing from disc magnet <NUM> to second magnet <NUM>, through a ferromagnetic shoulder portion of a tool holder TH, and back through side magnet <NUM>.

In combination, flux pathways fi and f<NUM> may generate a strong upward force to at least temporarily secure tool <NUM> within a corresponding tool holder. By generating two circuits that work in cooperation, tool <NUM> may drive a magnetic flux through a larger portion of tool holder TH relative to other tool and punch designs.

As further shown in <FIG>, first magnet <NUM> may be an NdFeB disc, which may also be large, while side magnets <NUM> may be smaller, axially magnetized NdFeB discs. Disc magnet <NUM> may also be an NdFeB magnet. Disc magnet <NUM>, however, may be
magnetized radially. Focal wedges <NUM> and lateral focal wedges <NUM> may each be made of iron-nickel compositions in one example.

<FIG> is a section view of tool <NUM>, taken along section A-A of <FIG>. <FIG> shows tool <NUM> in a release position caused by pressing button <NUM>. As shown in <FIG>, pressing button <NUM> causes disc magnet <NUM> to rotate. In some examples, disc magnet <NUM> will rotate up to about <NUM>°. Armature <NUM> may resist the rotation of disc magnet <NUM> beyond <NUM>° such that no internal bias member, e.g., spring, may be necessary. In some examples, a bias member may be included to prevent over-rotation of armature <NUM>. Rotation of disc magnet <NUM> causes the magnetic poles between disc magnet <NUM>, first magnet <NUM>, second magnet <NUM>, and each side magnet <NUM> to misalign, thereby nearly cancelling magnetic circuits x and y. Without a magnetic flux through tool <NUM> and a tool holder, the force urging tool <NUM> upward into a tool holder may be diminished, allowing removal of tool <NUM> from the tool holder.

As further shown in <FIG>, non-ferromagnetic sleeves <NUM> may house magnetic assemblies <NUM> and side magnets <NUM> within tool <NUM>.

<FIG> is a section view of tool <NUM> taken along line B-B of <FIG>. In this example, body <NUM> may extend the entire length of lateral cavity <NUM>.

<FIG> is an isometric view of tool <NUM> for a press brake or similar machine apparatus. As shown in <FIG>, tool <NUM> includes an external handle mechanism <NUM>. In this particular embodiment, handle mechanism <NUM> includes a slidable handle component that protrudes from front surface <NUM> of tool <NUM>. Handle mechanism <NUM> may be shaped to be graspable by a user. By moving handle mechanism <NUM> laterally, armature <NUM> may be moved laterally within tool <NUM>. Thus, handle mechanism <NUM> may be engaged to alternate tool <NUM> from a locked to an unlocked configuration.

<FIG> is a top view of tool <NUM>. As shown in <FIG>, handle mechanism <NUM> protrudes laterally outward from tool <NUM> for user access.

<FIG> is a section view of handle mechanism <NUM>, taken along line C-C of <FIG>. Handle mechanism <NUM> may be coupled, attached, or otherwise secured to armature <NUM> via transverse member <NUM>. In some examples, handle mechanism <NUM> may be directly or indirectly coupled to armature <NUM>. For instance, handle mechanism <NUM> may be inserted into an aperture or cavity defined by transverse member <NUM>. As depicted in <FIG>, handle mechanism <NUM> may be secured to the outer surface of transverse member <NUM>. In other embodiments, handle mechanism <NUM> may be integrally formed with transverse member <NUM>.

<FIG> is a section view of tool <NUM>, taken along line B-B of <FIG>. <FIG> illustrates tool <NUM> in a latched, engaged or "locked" configuration in which handle mechanism <NUM> is not urged laterally in a direction against the lateral force exerted by bias member <NUM>. Thus, bias member <NUM> remains uncompressed, and the polarity of the magnets <NUM>, <NUM> within armature <NUM> remain aligned with side magnets <NUM>.

In this example, handle mechanism <NUM> may be coupled with transverse member <NUM> of armature <NUM>. With handle <NUM> protruding laterally outward with from front surface <NUM>, armature <NUM> may not need to be directly engaged by a user. Thus, in this particular embodiment, tool <NUM> may lack external openings exposing transverse member <NUM>. As shown in <FIG>, end wall <NUM> may provide a barrier to the exposure of transverse member <NUM>.

<FIG> is a section view of tool <NUM> taken along line B-B of <FIG>. <FIG> shows tool <NUM> in a release, or unlocked, configuration in which handle <NUM> has been slid or otherwise urged to the left and bias member <NUM> is at least partially compressed, causing the magnets <NUM>, <NUM> to misalign with side magnets <NUM>, thus weakening the magnetic flux coupling between tool <NUM> and its corresponding tool holder. As shown in <FIG>, movement of armature <NUM> directly corresponds to movement of handle <NUM>.

<FIG> is an isometric view of tool <NUM> for a press brake or similar machine apparatus. Tool <NUM> may be smaller in profile relative to other tool configuration. Thus, tool <NUM> may only require two magnets to create a magnetic flux sufficient to at least temporarily hold tool <NUM> within a corresponding tool holder. As shown in <FIG>, tool <NUM> may include a top magnet <NUM> within tang <NUM>. A bottom magnet <NUM> may be positioned beneath tang <NUM>, laterally exposed at surface <NUM>. Tool <NUM> may further include one or more air gaps positioned to divert a magnetic flux toward the shoulders of a tool holder. In this particular configuration, tool <NUM> includes a first air gap <NUM>, a second air gap <NUM>, and a third air gap <NUM>, each defined by openings in surface <NUM>.

<FIG> is a front view of tool <NUM>. As shown in <FIG>, one or more top magnet components <NUM> may be exposed at reference face <NUM> of tool <NUM>.

<FIG> is a side view of tool <NUM>, showing surface <NUM>. Air gaps <NUM>, <NUM>, and <NUM> may be arranged in vertical fashion. The air gaps illustrated in <FIG> are each
circular or semicircular. In some examples, the size and/or shape of each air gap may vary. <FIG> also shows bottom magnet <NUM>, exposed at surface <NUM> and overlapping with air gaps <NUM> and <NUM>.

<FIG> is a top view of tool <NUM>. As shown in <FIG>, no magnetic assemblies or sub-assembly components may be visible on top surface <NUM>.

<FIG> is a section view of tool <NUM>, taken along line A-A of <FIG>. As shown in <FIG>, top magnet <NUM> may be housed within a non-ferromagnetic housing or sleeve <NUM>. Sleeve <NUM> may be made from various materials, including but not limited to aluminum or brass. Each of top magnet <NUM> and bottom magnet <NUM> may be an NdFeB magnet. Top magnet <NUM> may be axially magnetized, while bottom magnet <NUM> may be diametrically magnetized. As further shown in <FIG>, each air gap <NUM>, <NUM>, <NUM> may comprise a lateral through-hole. Tool <NUM> may be inserted into tool holder TH.

<FIG> is a section view of tool <NUM> at detail H, taken along line A-A of FIG. <FIG> shows magnetic flux F that may be generated by the arrangement of top magnet <NUM>, bottom magnet <NUM>, and the ferromagnetic components of tool holder TH. In particular, top magnet <NUM> may be axially magnetized and oriented such that its north pole is to the left of its south pole in the embodiment depicted. Bottom magnet <NUM> may be oriented such that its south pole is positioned to the left of its north pole. In this configuration, magnetic flux F may be guided through top magnet <NUM>, a portion of tool holder TH, and down to bottom magnet <NUM>. After passing through bottom magnet <NUM>, the magnetic flux may be guided upward toward top magnet <NUM>, after passing through another portion of tool holder TH.

In these examples, lower magnet <NUM> may be ring-shaped and circumferentially encompassed by tube <NUM>. Tube <NUM> may be made from various materials, including but not limited to brass or aluminum.

<FIG> is an isometric view of a tool <NUM> for a press brake or similar machine apparatus, showing internal structure. As shown in <FIG>, tool <NUM> may contain a plurality of fixed magnet island assemblies <NUM> and a release lever <NUM>. Tool <NUM> also includes a plurality of horizontal magnets <NUM> that collectively increase frictional holding of tool <NUM> within a corresponding tool holder. To facilitate removal of tool <NUM> from a tool holder, release lever <NUM> may be urged downward at distal end <NUM>, thereby causing protrusion <NUM> to pivot about pin <NUM> and exert an outward force against an inner surface of the tool holder, effectively prying tool <NUM> away from the holder. Such prying may weaken the magnetic circuit generated by magnetic island assemblies <NUM> and the holder by urging the coupling end of the tool body <NUM> from the tool holder, creating an air gap in the magnetic flux path between the tool body <NUM> and the tool holder. Other decoupling members, in addition or alternatively to lever <NUM>, may be implemented in various examples. Each decoupling member can be configured to mechanically urge tool <NUM> away from a tool holder by creating an air gap therebetween, thereby allowing removal of tool <NUM> from the holder.

The release or decoupling mechanism can include one or more pry bar or lever members <NUM> engaged with the tool or tool body <NUM>. As shown in <FIG>, each pry bar or lever member <NUM> extends from a first end <NUM> to a second end or protrusion <NUM>, with the second end <NUM> configured to selectively disengage the coupling end of the tool body <NUM> from the tool holder upon actuation of the first end. The first end <NUM> of the pry bar or lever member <NUM> may be accessible by a user, e.g., with the coupling end of the tool body <NUM> engaged in the tool holder, with the second end <NUM> of the pry bar or lever member <NUM> configured to protrude from the tool body <NUM> to selectively disengage the coupling end from the tool holder upon manipulation of the first end <NUM> by the user. A biasing element can be configured to bias the second end <NUM> of the pry bar or lever member <NUM> in a position disposed within the tool body <NUM>, absent manipulation of the first end <NUM>, or when the first end <NUM> is released.

<FIG> is an isometric view of a tool <NUM> for a press brake or similar machine apparatus. Tool <NUM> includes a plurality of fixed magnetic island assemblies <NUM> disposed within a load-bearing shoulder <NUM> of the tool. Two levers <NUM> protrude from their respective access windows <NUM> at a front surface <NUM> of the tool. Each lever <NUM> defines an actuating end <NUM> and a decoupling end <NUM>. Shoulder <NUM> defines two decoupling windows <NUM>, through which the decoupling end <NUM> of each lever <NUM> protrudes various distances depending on the position of each lever <NUM>.

In operation, magnetic island assemblies <NUM> can be configured to induce a magnetic flux coupling with a tool holder. Each magnetic island assembly <NUM> may include one or more permanent magnets, ferromagnetic components, and/or non-ferromagnetic components configured to induce a magnetic flux coupling with a tool holder. The magnetic elements comprising each magnetic island assembly can be non-adjustable, such that the strength of the magnetic flux coupling depends only on the proximity of the upper portion of the tool <NUM> with a tool holder.

To disrupt the magnetic flux coupling and remove tool <NUM> from its tool holder, a user can manipulate one or both levers <NUM>. Moving lever <NUM> downward, for example, causes the decoupling end <NUM> of the lever to move upward through decoupling window <NUM>. Because the surface of shoulder <NUM> can be pressed flat against a receiving shoulder of a tool holder when the two components are coupled, upward motion of a decoupling end <NUM> through decoupling window <NUM> mechanically urges tool <NUM> away from the tool holder by creating an air gap therebetween. As the size of the air gap increases, the strength of the magnetic flux coupling decreases, such that tool <NUM> may be removed from the tool holder, either by gravity or user-assisted removal.

<FIG> IB is a top transparent view of tool <NUM>. As shown, each lever <NUM> can rotate about a rotational axis defined by a pin <NUM>. The pins <NUM> extend into the body of tool <NUM>, anchoring the levers <NUM> to the body of the tool. In the embodiment shown, the coupling components, e.g., magnetic island assemblies <NUM>, and decoupling components, e.g., decoupling ends <NUM>, are each exposed at the surface of shoulder <NUM>, thus positioned to engage with the same mating surface of a tool holder.

<FIG> is a cross-sectional view of tool <NUM>, taken along section A-A of <FIG> <FIG>. As shown, lever <NUM> may be approximately L-shaped, with decoupling end <NUM> oriented approximately perpendicular to the actuating end <NUM>. Lever <NUM> is shown in a resting or coupling configuration, in which the actuating end <NUM> is perpendicular to the front surface <NUM> of the tool and decoupling end <NUM> does not protrude from the surface of shoulder <NUM> through decoupling window <NUM>.

<FIG> ID is a cross-sectional view of tool <NUM>, taken along section B-B of <FIG> IB. Lever <NUM> is shown in a disengaged or decoupling configuration, in which actuating end <NUM> of lever <NUM> has been pushed downward, thus forcing decoupling end <NUM> upward through decoupling window <NUM>. In this configuration, tool <NUM> may be mechanically urged from its tool holder. In some examples, each lever <NUM> must be in the decoupling configuration to effect release of tool <NUM> from the holder. In other examples, movement of one lever <NUM> to the decoupling configuration can suffice to urge tool <NUM> away from its tool holder.

<FIG> is a top transparent view of a tool <NUM> for a press brake or similar machine apparatus. Like tool <NUM>, tool <NUM> includes a plurality of fixed magnetic island assemblies <NUM> exposed at a surface of a load-bearing shoulder <NUM> of the tool. Tool <NUM> also includes two decoupling actuators <NUM>. Each decoupling actuator <NUM> is coupled to a pushbutton or slidable shaft or pin member <NUM>, which when moved to a decoupling position, mechanically urges a tool holder away from tool <NUM>.

Movement of the shaft or pin member <NUM> can be effected by movement of multiple movable components operationally coupled with each decoupling actuator <NUM>. In operation, rotation of decoupling actuator <NUM> is translated into rotation of an inner portion <NUM> of the decoupling actuator that protrudes within the body of the tool. Rotation of each inner portion <NUM> causes rotation of internal gear member <NUM>. Internal gear member <NUM> rotatably engages the shaft or pin <NUM> via a plurality of complementary grooves defined by the gear member and the pushbutton.

<FIG> is a front transparent view of tool <NUM>, showing magnetic island assemblies <NUM>, each pin or shaft member <NUM>, and each decoupling actuator <NUM>. In the decoupling configuration shown, each member <NUM> protrudes above the top surface of shoulder <NUM>, thereby mechanically urging tool <NUM> away from its corresponding tool holder. As further shown, each member <NUM> moves bi-directionally within a pushbutton cavity <NUM>, a portion of which is vacant upon displacement of the pushbutton above the top surface of the shoulder. The distance by which each member <NUM> protrudes from shoulder <NUM> may vary, and may depend at least in part on the strength of the magnetic flux coupling induced by tool <NUM> and a corresponding tool holder. For example, a stronger magnetic flux coupling may necessitate greater extension of each shaft or pin member <NUM> to mechanically urge tool <NUM> away from its tool holder, forming an air gap in the magnetic flux coupling.

Each decoupling actuator <NUM> may be manipulated by a user. In the specific embodiment shown, each decoupling actuator <NUM> comprises a rotatable knob. Alternative configurations of the decoupling actuators <NUM>, e.g., pushbuttons, levers, pins, switches, etc., are also within the scope of this disclosure.

<FIG> is a section view of tool <NUM>, taken along section A-A of <FIG>. As shown, a portion of decoupling actuator <NUM> may protrude from tool <NUM> for user
engagement, while inner portion <NUM> may extend a distance within the body of the tool. In some examples, inner portion <NUM> may anchor decoupling actuator <NUM> to tool <NUM>.

<FIG> is a section view of tool <NUM>, taken along section B-B of <FIG>. Gear member <NUM> is shown, along with pushbutton cavity <NUM>. By engaging with complementary grooves defined by the shaft or pin member <NUM>, rotation of gear member <NUM> causes linear movement of member <NUM>. In this manner, rotation of decoupling actuator <NUM> causes linear movement of member <NUM>, which can release tool <NUM> from the tool holder.

Suitable release mechanisms include a longitudinal shaft or pin member <NUM> engaged with the tool body <NUM>, the longitudinal shaft or pin member <NUM> extending from a first (e.g., bottom) end configured for actuation by a user to a second (e.g., top) end configured to selectively disengage the coupling end of the tool body <NUM> from the tool holder upon actuation of the first end. The longitudinal shaft or pin member <NUM> can be disposed in sliding engagement within the tool body <NUM>, e.g., with the second end configured to extend from the tool body <NUM> to selectively disengage the coupling end from the tool holder upon actuation of the first end.

<FIG> is a section view of tool <NUM> for a press brake or similar machine apparatus. As shown in <FIG>, tool <NUM> includes a magnetic coupling assembly MG with two isolated "island" magnetic assemblies configured for holding tool <NUM> within a tool holder TH (dashed lines), e.g., where tool holder TH utilizes a side-clamping mechanism.

Tool <NUM> includes first magnetic assembly <NUM> and second magnetic assembly <NUM> that together form a magnetic circuit or circuits through tang <NUM> of tool <NUM> and the adjacent portion of tool holder TH, sufficient to at least temporarily secure tool <NUM> to tool holder TH. As further shown in the figure, first magnetic assembly <NUM> may be secured to tool <NUM> via first fastener <NUM>. Similarly, second magnetic assembly <NUM> may be secured to tool <NUM> via second faster <NUM>.

<FIG> is a section view of a press brake punch or tool <NUM> (or similar machine tool component <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), with a magnetic coupling mechanism MG disposed in tang end <NUM>, opposite working end <NUM> of tool <NUM>. Coupling mechanism MG is configured for selective engagement of tool <NUM> within tool holder TH, as described herein.

Suitable examples of tool holder TH are described, for example, in <CIT> In any of the embodiments described herein, tool holder TH may comprise a preexisting tool holder lacking defined stationary or movable magnetic elements. As described herein, at least a portion of tool holder TH may comprise a ferromagnetic material. Tool <NUM> may additionally be secured by a bolt BO or similar mechanical fixture, as known in the art.

As described above, a safety latch mechanism is applied to Folding Press or Press Brake Tooling to hold the Punch up until it is clamped in place.

Press Brake punches with a safety latch which can selectively hold the punch up into the holder until the holder clamping is activated, are useful for installing large punches or multiple punches. There are various mechanisms for facilitating a releasable safety latch, one of which is a straight-in pushbutton and latch-pawl. There are additional latching mechanisms not described in the prior art; this document describes such mechanisms.

Suitable applications of the present safety mechanism include, but are not limited to, improved safety mechanism for tooling machinery described in <CIT>, <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>; <CIT>.

More specifically, a magnetic safety latch mechanism is applied to a folding press or press brake punch, for example where a protrusion at the top of the punch fits into a receiving, downward-facing cavity in the punch holder. Such systems may have an actuating mechanism in the upper tool holder or punch holder, which clamps all of the punches simultaneously, for securely holding said punches in place while folding or forming the work-piece, which is typically sheet metal. Such tool holder systems have the advantage of simplicity, but make it awkward to deploy multiple punches without some mechanism to hold some punches in place, temporarily, while others are being installed. Conventional safety tang designs, for their part, may require the punches to be installed in the correct order, and slid into the holder from one end. Other traditional safety latch mechanisms are known, such as laterally sliding or pivoting latches.

The present disclosure provides a magnetic assembly within the upper portion of each punch, to hold said punches safely in place, temporarily, so that the user's hands are free to install additional punches until the punch holder is activated to lock all of the punches in place for operation. Such magnetic assembly would ideally be comprised of an arrangement of strong (such as, but not limited to, NdFeB) permanent magnet assembly arranged within the punch such that the ferromagnetic properties of the punch itself are used to guide the magnetic flux in a circuit further involving the ferromagnetic or other material of the punch holder (e.g., typically medium-alloy steel), so that the punch will be urged upward by said magnetic flux so as to minimize non-ferromagnetic gaps (e.g., air) thus holding said punch up against the load-impinging shoulders of said punch holder.

It may be desirable that the magnetic circuit involves the shoulders of the punch holder: first to hold said punch firmly against said shoulders so that the punch is in an ideal position for clamping by the press, and secondly because the gap between the top of the punch tang and the inside of the holder is designed as clearance and is therefore not a precise or sufficiently small gap that it could be depended upon to form a reliable part of the magnetic circuit. Some embodiments can incorporate a movable part or movable parts of the magnetic circuit, e.g., permanent magnets or ferromagnetic components, which can be moved from one position with the magnetic circuit in a magnetically coupled or locked state, with a continuous flux path, and another position with the magnetic circuit in a magnetically decoupled or weakened (unlocked) state, e.g., by moving one or more components apart to create an air gap along the flux path, or by orienting a pair magnetic poles in opposition along the flux path.

Other variations of the magnetic assembly could use vertically aligned magnets or magnetic assemblies pressed into holes in the top of the tang, thus simplifying the machining needed to adapt stock punch material for receiving said assemblies, which assemblies would also protrude slightly from the top of the tang. A single or plural arrangement of press-fit, switchable magnetic assemblies could be deployed with an optimal protrusion from the punch tang to minimize the deficiency of the unknown gap at the tang top by using said resistively slidable magnetic assemblies which would thus adapt to the aforementioned gap variability. The magnetic assemblies could be made
switchable by various mechanism including that of having part of the magnetic circuit involve a slidable permanent magnet with poles alternately in alignment, favorably, with the magnetic circuit, creating a latched position, or opposing so as to weaken or even cancel the magnetic attraction to the punch holder, creating the released position.

Similar magnetic work-piece clamping systems can also be used as part holders for such machines as surface grinders, as well as the use of a magnetic tool-holder for press-brake tooling as described here. Other variations could employ magnets or magnetic assemblies installed in the top of the punch shoulder of the tang.

Claim 1:
A press brake tool system comprising:
a tool body (<NUM>) having a working end (<NUM>) configured for operation on a workpiece and a coupling end (<NUM>) configured for selective engagement with a tool holder, the working end spaced from the coupling end along the tool body; and
one or more magnetic elements (<NUM>) configured to induce a magnetic coupling between the tool body (<NUM>) and the tool holder, wherein the coupling end of the tool body (<NUM>) is magnetically engageable with the tool holder; and
a mechanism configured for selective disengagement of the coupling end of the tool body (<NUM>) from the tool holder;
characterized in that the mechanism comprises an actuator (<NUM>, <NUM>, <NUM>) engaged with the tool body (<NUM>), the actuator configured to urge at least a portion of the coupling end (<NUM>) from the tool holder to define an air gap therebetween.