BRPI1001621A2 - Method for mounting a press structure, and press - Google Patents

Abstract

METHOD FOR ASSEMBLING A PRESS STRUCTURE, AND, PRESS. A press provided with a structure comprising a table (2), an upper crossbar (4), and at least two interposed side spacers (3) defining together with the table (2) and the upper crossbar (4) a passageway. (100) having a longitudinal axis (A); the press structure comprising a stage of predisposing the table (2) and the upper crossbar (4) at a predetermined alternating initial distance defined by the spacers (3) or other suitable device, and characterized in that it further comprises the stages of: making at least one resistance ring (30); coupling the resistance ring (30) to the press structure such that it surrounds at least a portion of the table (2) and at least a portion of the upper crossbar (4); alternately spacing the table (2) and the upper crossbar (4) in contrast to the resistor ring (30) such that the resistor ring (30) is subjected to traction, and interposing at least one other spacer between the table (2) and the upper crossbar (4) in order to impose between them an alternating distance which is greater than the initial alternating distance so as to keep the resisting ring (30) in traction.

Description

"METHOD FOR ASSEMBLING A PRESS STRUCTURE, AND, PRESS"

The invention relates to a press and a method for mounting a press.

The invention relates to all types of presses, among which, for example, metal cold forming presses, plastic paramaterial presses and in particular ceramic presses.

As is known, presses comprise a rigid structure formed substantially as a portal, which offers a passageway through which articles to be pressed are progressively passed.

The direction of entry and exit of articles is parallel to the eixolongitudinal passage.

In the type of press, to which the present invention relates more particularly, the rigid structure of the press generally comprises a table and an upper crossbar which are kept parallel and alternately spaced by at least two vertical pieces or side spacers, and which are connected together by a ring. A resistor comprising one or more windings of a flexible element, such as a steel strip or cable, which surrounds both the upper transverse rail and the table.

The rigid structure of the press is designed to support a die, which generally comprises a lower half die fixed to the table, an upper half die which is fixed to a movable cross bar, which movable cross bar is connected to the upper transverse bar. fixed to the frame by means of one or more hydraulic actuators designed to move it in a vertical direction.

During each pressing stage, the upper half die is pressed against the lower half die in such a way that, by reaction, the press resistance spring is put into tension. To improve this tensile state, in the prior art the flexible element The resistance ring is placed in tension during its winding so as to pre-compress the lateral spacers between the table and the upper crossbar.

In this way, during the application of the pressing load, attraction, to which the flexible element is subjected, increases, while the decompression force to which the lateral spacers are subjected decreases.

In practice the tensile force, which is the most dangerous force, is entirely supported by the flexible element that exhibits high level mechanical characteristics and a small section, while lateral spacers, which have weaker mechanical characteristics, are subjected to compression stress, which creates fewer problems, especially regarding fatigue stresses. Notwithstanding the above, this precompression system has some disadvantages.

A first of these disadvantages is the difficulty of realizing the strength ring on structures having large dimensions.

Currently, the resistance ring is realized by rotating the rigid press frame and winding the flexible ring around the frame while keeping the ring tensioned. This implies the need to devise sufficiently large joining machines that are also sufficiently sturdy and powerful to handle the size and weight of the press. If the size and weight of the press exceeds certain limits, the joining machines become so large and expensive that they make the entire press. economically disadvantageous operation.

Another disadvantage is the difficulty of properly pre-compressing the rigid frame side spacers during rolling.

The precompression of the lateral spacers is proportional to the applied stress on the flexible element and the total resistant section, ie the cross section of the flexible element multiplied by the number of windings. The desired pre-compression level can be obtained by little windings of a flexible section grid element, or by many windings of a small section flexible element.

To subject a large section flexible element to traction, very powerful and expensive joining machines are required. However, if a small section flexible element is used, a lot of time is required to accomplish all of the required winding turns.

Another disadvantage is the difficulty of replacing structural components of the press once it is assembled.

As the flexible element is directly wound over the rigid press structure, replacement of a structural element usually has to be preceded by disassembly of the flexible element following a new joining operation.

Another disadvantage is the poor accessibility of certain areas of the rigid press structure.

This is because the flexible element is wound around the rigid frame of the press in such a way as to form a resistance ring, the shaft of which is parallel to the longitudinal axis of the rigid frame, that is, parallel to the direction of entry and exit of articles in and out. out of the press.

The flexible element extends parallel to the upper transverse bar, runs adjacent along the lateral spacers, and passes below the same, forming one or more coils that are coaxial and substantially frame the portal defined by the rigid structure of the press.

This arrangement allows the portal passage to be left fully open, as well as to allow the entry and exit of articles, which pass internally to the resistance ring surrounding the portal.

On the negative side, the flexible element windings almost completely cover the sides of the rigid structure, some components of which are therefore hidden and accessible only if the flexible element is disassembled.

The rigid frame components should also be provided with a receiving channel for the elementoflex windings, which further complicates and limits the press geometry.

The object of the present invention is to prevent or at least mitigate the above disadvantages with a solution that is simple, rational and relatively inexpensive.

These objectives are achieved by the characteristics of the invention as reported in the independent claims. Dependent claims outline preferred and / or particularly advantageous aspects of the invention.

Firstly, the invention makes available a new method for assembling a rigid press structure comprising the stages of:

biasing the table and the upper crossbar of the press at a predetermined alternating starting distance by interposing at least one first spacer or other suitable device;

separately making at least one strength ring having adequate tensile strength characteristics;

coupling the resistance ring to the table and to the upper crossbar such that the ring is wrapped around at least a portion of the table and at least a portion of the upper crossbar;

alternately distancing the table and the upper crossbar in opposition to the resistance ring so as to subject the ring to traction; and

interpose between the table and the upper crossbar at least one second spacer in order to adjust an alternating distance between them that is greater than the initial distance to maintain the tensile strength ring. The second spacer may be added to the first spacer or can replace the first spacer.

Thanks to this solution, the main disadvantages in the prior art are avoided.

Firstly, the resistance ring can be coupled to the rigid frame without rotating the press to wind the flexible element.

It follows that rigid frame turning machines are not required, which reduces costs and solves the difficulties connected with pre-compression of large presses.

Secondly, the resistance ring can be mounted on the rigid structure of the press without being put into tension at the same time, as it is already in tension thanks to the following alternate spacing between the table and the upper crossbar.

In a particularly advantageous aspect of the invention, the resistance ring is coupled to the crossbar and table with the anelsendo axis oriented transversely to the longitudinal axis of the press, in order to realize a configuration in which the inlet and outlet direction of the manufactured articles does not pass through the resistance ring

The invention, however, does not exclude the possibility that the resistance ring may be coupled to the crossbar and table with its axis oriented parallel to the longitudinal axis of the press, thereby obtaining a configuration which is similar to that of the prior art, in which the direction of entry and output of manufactured articles passes through the resistance ring.

The resistance ring may also be a modular ring intended to be stacked in a bundle together with other identical resistance rings.

As mentioned hereinabove, the resistance ring is realized by one or more windings of a flexible element, such as, for example, a cable or steel strip. In particular, the performance of the resistance ring preferably comprises stages of: predisposing an assembly rigid decomposers to form a provisional support frame; and

wrap the flexible member around the provisional support frame to connect the rigid components together.

Thanks to this solution, the table and the upper crossbar of the press can be simply and quickly connected while preparing the provisional support frame separately with the flexible element wrapped thereon, and then assembling the group thus obtained directly onto the press.

The shape and dimensions of the group formed by the provisional support frame and the flexible element can be selected and optimized so as not to interfere with the other press components and not create accessibility difficulties.

The group formed by the temporary support frame and the flexible element can also be disassembled and reassembled on the press without having to repeat the joining operation, thus facilitating the maintenance and / or, if necessary, replacement of the other structural organs of the press.

During winding of the provisional support frame, the flexible element may be subjected to light traction which, however, does not correspond to the final pre-pull that is desired for the press, but only to hold the rigid components of the provisional support frame together, and to enable easy group movement.

Therefore, the rolling of the flexible resilient element over the provisional support frame can be performed using much smaller, simpler and cheaper machines than those used in the prior art.

The invention also makes a new type of press available. The press is commonly provided with a rigid hatch structure comprising a table, a rigid upper crossbar and at least two interposed side spacers defining together with the table and the upper crossbar a passage having a longitudinal axis, which is the longitudinal axis of the press.

With the invention, the upper crossbar and the table are alternately connected by at least two resistance rings, each of which coils around at least a portion of the upper crossbar and at least a portion of the table, such that axes of the resistance rings are oriented transversely with respect to the axis of the press, and are preferably perpendicular thereto.

The resistor rings are further spaced alternately such that at least partially open the passageway defined by the table and the upper crossbar with the interposed side spacers.

Thanks to this solution, the two resistance rings can effectively connect the table and the upper crossbar, thus significantly reducing accessibility problems and geometric constraints of the press.

When they extend with a transverse axis, the resistance rings cover only the small portion of the press's rigid structure, which is thus almost entirely accessible without having to disassemble them.

Also, when they are alternately spaced apart, the resistance rings guarantee a stable joint, while nevertheless leaving the passage free to advance the manufactured articles at both inlet and outlet.

Resistance rings arranged with a transverse shaft also have much smaller dimensions than the prior art single strength ring, and can therefore be made much more easily.

While it is preferable to make such resistance rings as the inventive method outlined above, the invention also includes the possibility of producing the rings directly on the press using traditional methods.

Other features and advantages of the invention will emerge in a better manner from reading the following description, provided by way of non-limiting example, with the help of the figures illustrated in the drawing tables.

Figure 1 is a schematic front view of an invention press.

Figure 2 is section II-II of figure 1.

Figure 3 is a schematic front view of a resistance ring of the invention.

Figure 4 is section IV-IV of figure 3.

Figures 5, 6, 7 and 8 are schematic front views of the press of figure 1, shown during four successive stages to achieve pre-compression.

Figures 5A, 6A, 7A and 8A are respectively section V-V of figure 5, section VI-VI of figure 6, section VII-VII of figure 7, and sectionVIII-VIII of figure 8.

In the accompanying figures of the drawings, a ceramic die press 1 is illustrated, without excluding the possibility that the invention may also be applied to other press types, for example, metal cold forming presses and other plastic material presses.

Press 1 comprises a rigid structure substantially shaped as a portal delimiting a passage 100 having a longitudinal axis A.

The fabricated articles to be pressed are advanced through passage 100 in an inlet and outlet direction that is parallel to the long axis A.

The rigid structure schematically comprises a table 2e and a rigid upper crossbar 4 which are held parallel to each other by two vertical pieces or side spacers 3.

A movable crossbar 5 is connected to the upper transverse bar 4, which movable crossbar is activated by hydraulic actuators 6 to move vertically with respect to the underlying tables.

The rigid structure of the press is designed to support a ceramic die, which generally comprises a lower die which is fixed on the table 2 and an upper die which is fixed on the movable crossbar 6.

In the invention, the table 2 and the upper crossbar 4 are arranged at a predetermined alternating starting distance.

In the illustrated example, this operation is achieved by assembling the structure of figures 1 and 2, such that the lateral spacers 3 interposed between the table and the upper crossbar 4 define an initial distance.

Alternatively, the starting distance may be obtained by positioning the table 2 and the upper crossbar 4 over a mounting template.

The invention then includes predisposing two groups 10 of the type illustrated in FIGS. 3 and 4.

Each connection group 10 comprises a support frame 20, which is in the form of a frame.

The shorter sides of the support frame 20 are formed by a pair of semicircular block elements 21 arranged and specifically relative to each other, while the longer sides are made up of a pair of provisional parallel side bars 22 separating the two semicircular elements 21.

Each connecting group 10 further comprises a flexible element 30, provided with good strength and tensile characteristics, which is wound around the support frame 20 so as to fully realize a resistance ring.

The resistance ring develops in a plane that is parallel to the installation plane of the support frame 20 and is received and maintained in a channel 23 which is delimited by two flanges configured along the outer sides of the semicircular elements 21.

In the illustrated example, the flexible element 30 is a small plate or a ring-wound steel strip forming a single circumference around the support frame 20.

Alternatively, the flexible element 30 could be comprised of several winding circumferences of a cable or cable, or any other suitable element.

Generally speaking, the cross section and number of windings of the flexible element 30 around the support frame 20 are chosen based on the level of tension to be clamped after being installed over the rigid structure of the press 1.

In preparing the connection group 10, the flexible element 30 is wrapped around the support frame 20 so as to connect the circular elements 21 and the side bars 22 in a packet form, thereby obtaining a structural stability that is sufficient to move the disconnect group. as a single body.

This feature facilitates the following assembly operations of the connection group 10 on the rigid structure of the press 1, and additional fastening devices between the semicircular elements 21 and the superfluous side rails 22. For connection or joining, the flexible element 30 is preferably subjected to slight traction during the winding stage of the support frame 20.

This traction does not correspond to the pre-traction to be obtained on press 1, but only serves to block the elementosemicircular 21 against the sidebars 22.

It follows that the traction to which the flexible element 30 is subjected is somewhat small.

In particular, the traction values at stake are such that they do not lead to substantial technical difficulties, thus allowing the use of very simple and economical joining machines, including in the case where a flexible element 30 having a rather large section is chosen.

As illustrated in Figure 5, a first connection group 10 is inserted into a flank of the rigid frame of press 1 such that the support frame 20 contains an upper crossbar shoulder 4, a table shoulder 2, and the spacer side 3 that is brought between them.

The second connection group 10 is inserted in the same manner opposite the rigid structure of the press 1.

In this way, the resistance rings formed by the flexible elements 30 are oriented transversely, that is, they have axes which are transverse to the longitudinal axis A of press 1, and in the present perpendicular example.

The resistance rings are further alternately spaced along the direction of their axes so as not to obstruct the passageway defined by the rigid structure of the press and thus allow the manufactured articles to advance.

In particular, the resistor rings are positioned at opposite ends of upper crossbar 4 and table 2, where a respective lateral spacer 3 surrounds.

As illustrated in Figure 5A, the support frames 20 of the connection groups 10 are initially coupled to the rigid structure of press 1 with a small amount of vertical play.

After coupling of the connection groups 10, a hydraulic jack 7 is inserted vertically oriented between the table 2 and the upper crossbar 4.

In the illustrated example, the hydraulic jack 7 is supported on the table 2 and acts directly against the movable crossbar 5, which is supported on the upper crossbar 4 by interposing two rigid blocks 8.

The hydraulic jack 7 is activated to raise and distance the upper transverse handle 4 from the side spacers 3 and the table (see figure 6A), in contrast to the flexible elements 30 of the disconnect groups 10.

In this way, the resistance rings formed by the flexible elements 30 are placed in tension and slightly elongated.

The semicircular elements 21 of the support frame 20 thus alternately sedicate, protruding from the relative vertical parts 22.

During maintenance of the raised upper crossbar 4, the sidebars 22 of both of the connecting groups 10 are removed, after which two other rigid spacers 9 of the same thickness are disposed, which are inserted separately into the free space left between the spacer 3 and the upper crossbar 4 of the press (figure 7A).

When these operations are completed, the hydraulic jack 7 is shortened and removed, such as to let the upper crossbar 4 rest on the rigid spacers 9 and 3. In this way, the upper crossbar 4 is required to be a distance from the table 2 , which is greater than the initial distance by the same amount as the thickness of the spacers 9.

This thickness is chosen in such a way that the resisting rings formed by the flexible elements 30 remain in tension, compressing the side spacers 3 between the upper crossbar 4 and the table 2, and thus preloading the entire rigid structure of the press 1.

Of course, the thickness of the spacers 9 is chosen based on the preload value to be applied to the rigid structure of press 1.

Of course, one skilled in the art could carry numerous modifications of a technical-application nature to press 1 and the relative mounting method, without departing from the scope of the invention as claimed here below.

If, for example, the table 2 and the upper crossbar 4 were initially positioned over a mounting jig, it would be possible to place the resistance rings made by the flexible elements 30 into traction, and then to interpose only two height spacers between the upper crossbar 4 and Table 2, equal to the sum of the previously described spacers 3 and 9.

Claims (14)

1. Method for mounting a press frame, the press frame comprising a table (2), an upper crossbar (4), and at least two interposed side spacers (3) defining together with the table (2) and upper crossbar (4) A passageway (100) having a longitudinal axis (A), characterized in that it is for mounting the press structure comprising a step of pre-disposing the table (2) and the upper crossbar (4) at a predetermined alternating starting distance defined by spacers. (3) between the table and the transverse rail, characterized in that it comprises the additional steps of: separately making at least one resistance ring (30), making said resistance ring comprising the step of realizing a support frame ( 20) comprising at least two block members (21) separated by two side bars (22), and of wrapping a flexible element around the support frame (20) to connect the blocking elements (21) and the side bars (22) together; coupling the support frame (20) to the press structure such that the resistance ring (30) surrounds at least a portion of said portion (2) and at least a portion of the upper crossbar (4); alternately distancing the table (2) and the upper transverse bar (4) in contrast to the resistance ring (30) such that the resistance ring (30) is subjected to traction; and interposing at least one other spacer (9) between the table (2) and the upper crossbar (4) in order to interpose between them an alternating distance which is greater than the initial alternating distance so as to keep the resistance ring (30) in traction. Method according to claim 1, characterized in that the resistance ring (30) is coupled such that an axle itself is oriented parallel to the longitudinal axis (A) of the depressed structure. Method according to claim 1, characterized in that the resistance ring (30) is coupled such that the axle itself is oriented transversely to the longitudinal axis (A) of the press structure. Method according to claim 3, characterized in that it comprises making at least two of the resistor rings (30), and coupling them to the press structure in such a way that they are spaced apart from each other in order to leaving the passage (100) of the press structure at least partially open. Method according to claim 1, characterized in that the resistance ring (30) comprises one or more windings of a flexible element. Method according to claim 5, characterized in that the flexible element is a flexible cable. Method according to claim 5, characterized in that the flexible element is a flexible tape. A method according to claim 5, characterized in that making the resistance ring (30) comprises stages of: predisposing a set of rigid components (21, 22) to form the support frame (20); and wrapping the flexible element around the support frame (20) to connect the rigid components (21, 22) constituting the flexible element together. The method according to claim 8, characterized in that the support frame (20) comprises at least one receiving channel (23) for the flexible element which is wound around said support frame (20). 10. Press, comprising a rigid structure comprising a table (2), and at least two interposed side spacers (3) defining, together with the table (2) and a top crossbar (4), a passageway (100) having a longitudinal axis (A), characterized in that the upper crossbar (4) and the table (2) are alternately connected by at least two resistance rings (30), these resistance rings (30), each of which comprises a flexible element winding around the support frame (20), which is coupled to the press structure such that the resistance ring (30) is wrapped around at least a portion of the upper crossbar (4) and at least a portion of the table (2) and such that the axis of the resistance ring (30) is oriented transversely with respect to the longitudinal axis (A) of the press structure, each support frame comprising at least two block elements (21). ) separated by r two available side bars (22) made together by the flexible element wound thereon. Press according to claim 10, characterized in that the resistor rings (30) are positioned at opposite ends of the upper crossbar (4). Press according to claim 10, characterized in that each of the resistance rings (30) is wound around a respective lateral spacer (3) of the press structure. Press according to claim 10, characterized in that each of the resistor rings (30) comprises one or more windings of a flexible element. Press according to claim 10, characterized in that the lateral spacers comprise two aligned portions (3, 9).