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WO-2026093824-A1 - PRESSING MEMBER, IN PARTICULAR FOR SINTERING PRESSES

WO2026093824A1WO 2026093824 A1WO2026093824 A1WO 2026093824A1WO-2026093824-A1

Abstract

A pressing member, in particular for a pressing assembly of a sintering press for performing sintering of electronic components on a substrate, comprises a rigid stem (10) and an end foot (12; 112) coupled to the rigid stem by means of a ball joint (16) which allows an oscillation of the end foot with respect to the rigid stem. The ball joint consists of a ball (18) housed in a ball seat (20; 120) jointly formed by an end stem surface (22; 122) and by an apical foot surface (24; 124) facing said end stem surface.

Inventors

  • SCHIVALOCCHI, Nicola

Assignees

  • AMX - AUTOMATRIX S.R.L.

Dates

Publication Date
20260507
Application Date
20250926
Priority Date
20241031

Claims (15)

  1. 1. A pressing member, in particular for a pressing assembly of a sintering press for sintering electronic components on a substrate, comprising a rigid stem (10) extending along a stem axis (X) , and an end foot (12; 112) connected to one end of the rigid stem (10) , the end foot (12; 112) being coupled to the rigid stem (10) by means of a ball joint (16) which allows the end foot to oscillate with respect to the rigid stem, characterized in that the ball joint consists of a ball (18) accommodated in a ball seat (20; 120) jointly formed by an end stem surface (22; 122) and an apical foot surface (24; 124) facing said end stem surface.
  2. 2. Pressing member according to claim 1, wherein the centre of the ball belongs to the stem axis (X) .
  3. 3. Pressing member according to claim 1 or 2, wherein the end stem surface (22; 122) forms a concave stem surface (22a; 122a) in the shape of a spherical cap complementary to the ball (18) .
  4. 4. Pressing member according to any one of the preceding claims, wherein the apical foot surface (24) forms a concave foot surface (24a) in the shape of a spherical cap complementary to the ball.
  5. 5. Pressing member according to any one of claims 1-3, wherein the apical foot surface (124) forms a concave foot surface (124a) having a radius of curvature greater than the radius of the ball (18) .
  6. 6. Pressing member according to claim 4 or 5, wherein said apical foot surface (24, 124) comprises an annular peripheral portion (24b; 124b) of f rustoconical shape converging into the concave foot surface (24a; 124a) .
  7. 7. Pressing member according to any one of the preceding claims, wherein at least one release recess (28a, 28b) is obtained in the ball seat, which reduces the contact surface between the ball (18) and the ball seat (20; 120) .
  8. 8. Pressing member according to claim 7, wherein at least one release recess (28a, 28b) is obtained about the stem axis (X) in the end stem surface and/or in the apical foot surface .
  9. 9. Pressing member according to any one of the preceding claims, wherein the rigid stem (10) and the end foot (12; 112) are made of a first material and the ball (18) is made of a second material different from the first material .
  10. 10. Pressing member according to claim 9, wherein the second material has a lower friction coefficient than the friction coefficient of the first material.
  11. 11. Pressing member according to any one of the preceding claims, further comprising: - axial connection means (30) suitable for axially constraining and with clearance the end foot (12; 112) to the rigid stem (10) ; - elastic alignment means (32) acting axially between the rigid stem and the end foot so that the end foot is movable between an advanced resting position, in which it is axially urged by said elastic alignment means (32) so as to be engaged by the axial connection means (30) to take a position coaxial to the stem axis (X) , and an active retracted position, in which it is disengaged from the axial connection means (30) and engaged by the ball (18) .
  12. 12. Pressing member according to claim 11, wherein said axial connection means (30) comprise: - a pair of lateral coupling arms (34) opposite to each other extending axially from the end of the rigid stem towards the end foot and each forming a respective radial tooth (34' ) facing the stem axis (X) ; - a pair of radial recesses (36) obtained in the end foot, each radial recess (36) being axially engaged, with clearance, by a respective radial tooth (34' ) .
  13. 13. Pressing member according to any one of claims 11-12, wherein said elastic alignment means comprise at least one pair of helical springs (40) opposite to each other with respect to the stem axis (X) and extending parallel to the stem axis (X) into respective spring seats (42) obtained partly in the rigid stem and partly in the end foot.
  14. 14. Pressing member according to any one of the preceding claims, wherein the end foot forms, on the opposite side with respect to the rigid stem, a flat end surface (14) suitable for abutting against an object to be pressed.
  15. 15. Pressing member according to any one of the preceding claims, wherein the distance between the apical foot surface (24; 124) and the flat end surface (14) is less than or equal to twenty times the radius of the ball (18) .

Description

DESCRIPTION "PRESSING MEMBER, IN PARTICULAR FOR SINTERING PRESSES" [ 0001 ] The present invention relates to a pressing member, in particular, but not exclusively, for a pressing assembly of a sintering press for sintering electronic components on a substrate . [ 0002 ] The pressing member forming the subject-matter of the present invention can be used in all applications in which it is necessary to exert a pressing action on an object that may have a pressing surface, on which the pressing member acts , that is not orthogonal to the direction of the applied force . One of these applications is the sintering of electronic components on a substrate . [ 0003 ] As is known, in certain electronic applications , integrated electronic components , for example diodes , IGBTs , thermistors , MOSFETs , are fixed to a substrate by interposing a sintering paste . In order for each component to be properly sintered, it must be pressed with a force proportional to its projection surface and subjected to a predetermined temperature for a certain time interval . An example of a sintering press employing pressing members forming the subject-matter of the present invention is described in WO2018122795A1 , in the name of the same Applicant . [ 0004 ] Since the layer of sintering paste on which the electronic components to be sintered are positioned may have a non-uniform thickness , it may happen that some electronic components are inclined with respect to the support , i . e . they have respective flat pressing surfaces that are not perfectly orthogonal to the direction of the force exerted by the pressing members . [ 0005 ] In order to reduce such drawback, Italian patent 102018000007256 in the name of the same Applicant proposed a pressing member having a terminal part provided with a spherical portion so as to be able to tilt with respect to the upper portion of the pressing member itself so as to adapt to the component to be sintered . [ 0006 ] This technical solution, however, proved to be complex to implement and in any case subject to undesirable friction forces acting in particular on the spherical portion . [ 0007 ] The object of the present invention is to provide a pressing member of the type mentioned above, thus capable of overcoming the problem of adapting the pressing member to possible unforeseen inclinations of the flat pressing surfaces of the objects to be pressed with respect to the direction of the force exerted by the pressing members , but free from the drawbacks mentioned above with reference to the prior art . [ 0008 ] This object is achieved by a pressing member according to claim 1 . The dependent claims describe preferred or advantageous embodiments of the pressing member according to the invention . [ 0009 ] The features and advantages of the pressing member according to the invention will in any case become evident from the following description of preferred embodiments thereof , given by way of example and not limitation, with reference to the accompanying figures , in which : [ 00010 ] - Figure 1 is an axial section of an end portion of a pressing member according to the present invention, in a first embodiment ; [ 00011 ] - Figure 2 is an axial section of the pressing member of Figure 1 , according to a sectional plane orthogonal to that of Figure 1 ; [ 00012 ] - Figure 3 is a perspective axial section of the end portion of the pressing member of Figures 1 and 2 , according to the sectional plane of Figure 1 ; [ 00013 ] - Figure 4 is an axial section of a pressing member according to the present invention, in a second embodiment and according to the same sectional plane as Figure 1 ; [ 00014 ] - Figure 5 is an elevation view of a pressing member according to the present invention, in an active configuration; and [ 00015 ] - Figure 6 is an axial section of a pressing member according to the present invention, according to the same sectional plane as Figure 1 . [ 00016 ] In the following description, all directional references ( for example, upper, lower, upward, downward, left , right , to the left , to the right , top, bottom, above, below, vertical, horizontal, clockwise and counterclockwise ) are used solely for identification purposes to assist the reader in understanding the described embodiments and do not constitute limitations , particularly with regard to the position, orientation or use of the described embodiments . [ 00017 ] The connecting references ( for example, fixed, coupled, connected and the like ) must be interpreted broadly and may include intermediate elements between a connection of elements and relative movement between elements . Therefore, the connecting references do not necessarily imply that two elements are directly and fixedly connected to one another . [ 00018 ] Furthermore, elements common to the described embodiments will be indicated with the same reference numerals . [00019] In the accompanying drawings, 1; 100 denote a pressing member according to