Gripper for handling hollow bodies and manufacturing method

Abstract

A branch of a clamp for handling hollow bodies in a plant manufacturing containers made of plastic material, the handling clamp comprising two branches intended to be held by a holding member and being intended to grip a hollow body, the branch comprising a base, and a jaw extending from the base. The base has a front edge intended to be in contact with the hollow bodies. The branch is formed by a metal core extending in the jaw set back from the front edge, and a plastic supplement at least partially covering the metal core, the plastic supplement constituting at least the front edge and being secured to the metal core.

Claims

1. A clamp (1) comprising two branches (10) held by a portion thereof for gripping hollow bodies, each branch (10) comprising: a base (2) having cooperation means (20) to cooperate with the portion of the clamp; a jaw (3) extending from the base (2) and having a front edge (30) in contact with the hollow bodies; wherein each branch (10) is formed by: a metal core (4) at least partially constituting the cooperation means (20), the metal core (4) extending in the jaw (3) set back from the front edge (30); a plastic supplement (5) at least partially covering the metal core (4), the plastic supplement (5) constituting at least the front edge (30) and being secured to the metal core (4); and wherein the metal core (4) comprises: a metal block (45) at least partially constituting the cooperation means (20); a metal rod (46) coupled to the metal block (45) and extending from the metal block (45) into the jaw (3).

2. The clamp (1) as claimed in claim 1, wherein the metal block (45) has two housings (45) each capable of receiving the metal rod (46) for coupling the rod to the metal block (45), the housings (45) being symmetrical relative to one another with respect to a central plane (P) of symmetry of the metal block (45).

3. The clamp (1) as claimed in claim 2, wherein the metal core (4) is embedded in the plastic supplement (5).

4. The clamp (1) as claimed in claim 3, wherein the plastic supplement (5) is a one-piece part.

5. The clamp (1) as claimed in claim 3, wherein the plastic supplement (5) is obtained by additive manufacturing in plastic.

6. The clamp (1) as claimed in claim 1, wherein the metal core (4) is a flat metal sheet.

7. The clamp (1) as claimed in claim 6, wherein the metal core (4) has at least one through-hole (42, 43) formed in a thickness of the core, the plastic supplement (5) having two faces situated on either side of the through-hole (42, 43) and being secured through the through-hole (42, 43).

8. The clamp (1) as claimed in claim 1, wherein the metal core (4) has at least one through-hole (42, 43) formed in a thickness of the core, the plastic supplement (5) having two faces situated on either side of the through-hole (42, 43) and being secured through the through-hole (42, 43).

9. The clamp (1) as claimed in claim 1, wherein the metal core (4) is embedded in the plastic supplement (5).

10. The clamp (1) as claimed in claim 1, wherein the plastic supplement (5) is a one-piece part.

11. The clamp (1) as claimed in claim 1, wherein the plastic supplement (5) is obtained by additive manufacturing in plastic.

12. A method for manufacturing each branch (10) of the clamp (1) for handling hollow bodies as claimed in claim 1, wherein the method comprises: obtaining the metal core (4); securing the plastic supplement (5) to the metal core (4), the plastic supplement (5) being produced as at least partially covering of the metal core (4).

13. The manufacturing method as claimed in claim 12, further comprising a step of additive manufacturing of the plastic supplement (5).

14. The manufacturing method as claimed in claim 13, wherein the additive manufacturing step comprises: a first substep of printing of an intermediate form of the plastic supplement (5), the intermediate form having an imprint of the metal core (4) open on a face of the intermediate form; a second substep of printing of a final form of the plastic supplement (5) from the intermediate form; and wherein the method further comprises an insertion step of inserting the metal core (4) into the imprint offered by the intermediate form, the insertion step being interposed between the first printing substep and the second printing substep.

15. The manufacturing method as claimed in claim 14, wherein the metal core (4) is heated prior to the insertion step.

16. The manufacturing method as claimed in claim 15, wherein the metal core (4) is at least partially covered by a printing lacquer prior to the insertion step.

17. The manufacturing method as claimed in claim 14, wherein the metal core (4) is at least partially covered by a printing lacquer prior to the insertion step.

Description

(1) Other features and advantages of the invention will emerge more clearly on reading the following description of two preferential embodiments of the invention, given as illustrative and nonlimiting examples, and the attached drawings in which:

(2) FIG. 1 is a top perspective view of a hollow body handling clamp having two branches according to the invention;

(3) FIG. 2 is a top perspective view of a branch comprising a metal core and a plastic supplement covering the metal core, the plastic supplement being represented in partial cross section, according to a first embodiment;

(4) FIG. 3 is a top perspective view of the metal core, according to the first embodiment;

(5) FIG. 4 is a bottom perspective view of a hollow body handling clamp, comprising two branches according to a second embodiment of the invention, one of the branches being without its plastic supplement and the other of the branches having its metal reinforcement visible by transparency through its plastic supplement;

(6) FIG. 5 is a top perspective view of a metal block of the metal reinforcement of the branch according to the second embodiment;

(7) FIG. 6 is a top perspective view of the plastic supplement of the branch according to the second embodiment.

(8) The expression hollow body is employed hereinbelow to denote both a preform and a final container having undergone a blow-molding operation or a stretch blow-molding operation.

(9) Referring to FIG. 1, a hollow body handling clamp 1 is represented. Such a handling clamp 1 is used in a plant manufacturing containers made of plastic material comprising the following machines: blowing machine, filling machine, labelling machine, etc.

(10) This handling clamp 1 comprises two branches 10.

(11) These two branches 10 are designed to be held by a holding member (not represented) of the manufacturing plant. Each of the branches 10 to this end comprises cooperation means 20 intended to cooperate with the holding member to establish a coupling of the branch 10 to the holding member.

(12) The branches 10 are intended to grip the hollow bodies by their neck. These two branches 10 jointly delimit a space 100 for receiving hollow bodies when they are gripped.

(13) The hollow bodies are essentially fitted in this receiving space 100.

(14) More specifically, each of the branches 10 is held in position by the holding member and the branches 10 have only a relative mobility with respect to one another to allow the insertion, the conveying and the removal of the hollow bodies.

(15) Referring to FIGS. 1, 2 and 4, each branch 10 comprises: a base 2; a jaw 3 which extends from the base 2.

(16) The base 2 has the cooperation means 20 intended to cooperate with the holding means to establish a coupling of the branch 10 to the holding member. These cooperation means take the form of a hole passing through the base 2.

(17) This base 2 has an essentially rectangular parallelepipedal form.

(18) The jaw 3, for its part, has a front edge 30 which is intended to enter into contact with the hollow bodies.

(19) More particularly and with reference to FIGS. 1, 2 and 4, a jaw 3 comprises: a body 310 extending directly from the base 2; a head 311 situated at the end of the body 310 opposite the base 2 with respect to the body 310, and which has the front edge 30.

(20) As illustrated by FIGS. 1, 4 and 6, the front edge 30 comprises a setback 300. The necks of the hollow bodies gripped by a handling clamp 1 rest on the setback 300 offered by each of the branches 10 of the handling clamp 1.

(21) The form of the branch 10 of the handling clamp 1 according to the invention is thus identical to that of the branches of the original metal handling clamps.

(22) These original metal handling clamps are produced by precision mechanical machining. When a branch of the original clamp breaks, the branch 10 according to the invention is intended to temporarily replace it.

(23) According to the principle of the invention and referring to FIGS. 1 to 6, the branch 10 is formed by a metal core 4 and a plastic supplement 5.

(24) The metal core 4 at least partially constitutes the base 2 and the cooperation means 20.

(25) Referring to FIGS. 2 and 4, this metal core 4 extends in the jaw 3 set back from the front edge 30. The function of the metal core 4, by extending in the jaw 3, is to stiffen this jaw.

(26) Thus, the end of the metal core 4, in the jaw 3 and more specifically in the head 311 of the jaw 3, has a portion situated set back from and along the front edge 30.

(27) According to the principle of the invention and with reference to FIGS. 1 to 6, the plastic supplement 5: at least partially covers the metal core 4; constitutes at least the front edge 30 of the jaw 3.

(28) The expression the plastic supplement constitutes at least the front edge is understood to mean that only the plastic supplement forms the front edge 30. The metal core 4 does not form or does not constitute at least a part of this front edge 30. Thus, only the plastic supplement 5 of the branch 10 of the handling clamp 1 according to the invention can enter into contact with a hollow body.

(29) This plastic supplement 5 is secured to the metal core 4.

(30) According to the embodiment illustrated by FIGS. 1 to 3, the plastic supplement 5 totally covers the metal core 4 apart from a first through-hole 41 situated in the base 2.

(31) Referring to FIGS. 1 and 2, the metal core 4 is partially embedded in the plastic supplement 5.

(32) This plastic supplement 5 is notably a single-piece part and is in particular obtained by additive manufacturing in plastic.

(33) In other words, the plastic supplement 5 is produced by three-dimensional printing (3D printing) around the metal core 4.

(34) The plastic supplement 5 has an imprint of the metal core 4 allowing it to accommodate the latter.

(35) The imprint corresponds notably to the outer form of the metal core 4 plus a gap of 0.1 mm.

(36) Referring to FIG. 2, the metal core 4 is flat and is more particularly produced in a flat metal sheet.

(37) The metal core is also more specifically obtained by laser cutting of a flat metal sheet.

(38) This metal core 4 comprises: the first through-hole 41 which is intended to contribute to the formation of the cooperation means 20; a second through-hole 42; a third through-hole 43.

(39) The second hole 42 and the third hole 43 contribute to the securing of the plastic supplement 5 on the metal core 4.

(40) In fact, the plastic supplement 5 has two faces situated on either side of the second hole 42 and the third hole 43, and it is secured through these holes 42, 43.

(41) More specifically, the metal core 4 extends longitudinally with, in succession: a first section 401 comprising the first hole 41; a second section 402 comprising the second hole 42 and the third hole 43; a third section 403.

(42) According to FIGS. 2 and 3, in cooperation with the plastic supplement 5: the first section 401 of the metal core 4 contributes to forming the base 2 of the branch 10; the second section 402 of the metal core 4 contributes to forming the body 310 of the jaw 3; the third section 403 of the metal core 4 contributes to forming the head 311 of the jaw 3.

(43) The third section 403 of the metal core 4 notably has a curved form closely following the form of the front edge 30 formed by the plastic supplement 5.

(44) According to the second embodiment illustrated by FIGS. 4 to 6, the plastic supplement 5 partially covers the metal core 4.

(45) Furthermore, according to this second embodiment, the metal core 4 comprises: a metal block 45; a metal rod 46 coupled to the metal block 45.

(46) The metal block 45 at least partially constitutes the base and the cooperation means.

(47) The metal rod 46 extends from the metal block 45 in the jaw 3.

(48) The metal block 45 has a first through-hole 41 which is intended to contribute to the formation of the cooperation means 20.

(49) To allow the coupling of the metal rod 46, the metal block 45 has two housings 450 each capable of receiving the metal rod 46.

(50) Referring to FIG. 5, these housings 450 are formed on either side of a central plane P of symmetry of the metal block 45.

(51) As can be seen in FIG. 4, the metal block 45 is designed to be used to manufacture a right branch 10a or a left branch 10b of a hollow body handling clamp 1.

(52) This metal block 45 can be reused if the plastic supplement 5 were to give way.

(53) This metal block 45 can be produced by precision mechanical machining.

(54) To manufacture a right branch 10a or a left branch 10b, the metal rod 46 must be inserted into the appropriate housing 450.

(55) The plastic supplement 5 then totally covers the metal rod 46 and partially covers the metal block 45.

(56) The metal block 45 has a particular relief on its surface intended to be covered by the plastic supplement 5. This particular relief is intended to enhance the securing of the plastic supplement 5 to the metal block 45.

(57) More particularly and as illustrated by FIGS. 4 and 5, the metal block 45 comprises an end 47, from which the plastic supplement 5 extends, that has a T-shaped profile, and a groove 471 at right angles to the T-shaped profile.

(58) In other words, at its end 47 the block 45 has two tabs 470, one of which is situated on a top face of the end 47, and the other of which is situated on a bottom face of the end 47. The groove 471 extends at right angles to the tabs 470 running centrally through them.

(59) Referring to FIG. 6, the plastic supplement 5 has: two grooves 51 complementing the form of the tabs 470; a bead 52 complementing the form of the groove 471.

(60) Obviously, the plastic supplement 5 also has a hole 53 complementing the form of the metal rod 46.

(61) The branch 10 of the handling clamp 1 is obtained using the manufacturing method according to the invention.

(62) This manufacturing method comprises: a prior step of obtaining of a metal core 4; a step of securing of a plastic supplement 5 on the metal core 4, the plastic supplement 5 being produced at least partially covering the metal core 4.

(63) For the prior step of obtaining of a metal core 4, either the metal core 4 is manufactured, or it is acquired.

(64) For example, in the case where the metal core 4 comprises a metal block 45 produced by precision mechanical machining, this block 45 can be purchased.

(65) The manufacturing method advantageously comprises a step of additive manufacturing of the plastic supplement 5.

(66) The securing step can take place at the same time as the additive manufacturing step, for example if the plastic supplement 5 is a single-piece part and at least partially embeds the metal core 4.

(67) In this case, the additive manufacturing step comprises, in succession: a first substep of printing of an intermediate form of the plastic supplement 5; a second substep of printing of a final form of the plastic supplement from the intermediate form.

(68) The additive manufacturing step is advantageously parameterized using a three-dimensional rendering of the original handling clamp which is created by precision mechanical machining. This three-dimensional rendering is reworked by subtracting the volume of the metal core, which must be embedded at least partially, plus a gap of 0.1 mm.

(69) The intermediate form of the plastic supplement 5 has an imprint of the metal core 4 open on a face of the intermediate form.

(70) The manufacturing method then comprises a step of insertion of the metal core 4 in the imprint offered by the intermediate form of the plastic supplement 5.

(71) This insertion step is interposed between the first printing substep and the second printing substep so as to allow the metal core 4 to be at least partially embedded in the plastic supplement 5, and thus allow the metal core 4 and the plastic supplement 5 to be joined.

(72) To enhance the bond of the plastic supplement 5 on the metal core 4, the metal core 4 is heated prior to the insertion step.

(73) For example, if the material used to print the plastic supplement 5 has a heating print platen, then the metal core 4 is deposited on the platen prior to the first printing substep.

(74) Furthermore, the metal core 4 is at least partially covered with a printing lacquer prior to the insertion step.

(75) A printing lacquer corresponds to a product sprayed onto a surface intended to be in contact with the 3D-printed material. This printing lacquer makes it possible to enhance the adhesion (or in other words the bond) of the material printed on the surface sprayed with the lacquer.

(76) A plant manufacturing containers made of plastic material can incorporate a three-dimensional printer implementing the manufacturing method according to the invention.

(77) Advantageously, the printer comprises an interface for selecting a clamp to be produced and means of connection to a remote server hosting handling clamp plans.

(78) Thus, the manufacturing of a handling clamp is initiated using the selection interface which leads to connection to the remote server and downloading of the plan corresponding to the desired handling clamp.

(79) This remote server can be situated with the designer of the container manufacturing plant, and administered by this designer. Thus, the designer can rapidly make modifications to the various handling clamp plans, for example to correct identified manufacturing defects, all of this being transparent for the end user who only needs to initiate the manufacturing of a handling clamp.