WO2005056388A1

WO2005056388A1 - Pincer, in particular for holding bags

Info

Publication number: WO2005056388A1
Application number: PCT/IT2003/000829
Authority: WO
Inventors: Stefano Rolleri
Original assignee: Levati Food Tech S.R.L.
Priority date: 2003-12-11
Filing date: 2003-12-17
Publication date: 2005-06-23
Also published as: ITPR20030108A1; AU2003300733A1

Abstract

A pincer (1), in particular for holding envelopes, comprising at least a pair of gripping elements (2, 3) operating between a first operative configuration for holding the envelopes and a second operative configuration for their release. The pincer (1) comprises a support structure (4) for a first (2) of said gripping elements (2, 3), said support structure (4) having at least a guide (5). The pincer (1) is equipped with a cursor (6) provided with a second gripping element (3) and movable with rotary-translatory motion within the guide (5), to move the gripping elements (2, 3) closer to and further away from each other. The guide (5) and the cursor (6) are associated with means able to activate the rotary-translatory motion of the cursor (6) itself.

Description

PINCER, IN PARTICULAR FOR HOLDING BAGS

TECHNICAL FIELD AND BACKGROUND ART.

The present invention relates to a pincer, in particular for holding envelopes, of the type described in the preamble to claim 1.

In the food and/or pharmaceutical industry, there is a particularly felt need for automatic machines capable of filling envelopes or bag packages, preferably of the flexible kind, with products of any nature, be they liquids, solids, or in powder form. To perform their assigned task, such machines must first of all be provided with means capable of gripping and holding the envelopes and/or the bags to be filled, or otherwise processed.

Currently, envelopes are held by means of pincers or mechanical hands, which grip the lateral and opposite edges of a package, in order to keep it in position, for example during the opening or filling operations. Especially in this latter case it is necessary to keep the package firmly in position, to allow the insertion of a filling valve which dispenses the product directly into the interior of the package.

According to the prior art, there are numerous types of pincers or mechanical hands, all generally constituted by a pair of jaws pivotally engaged to each other and actuated by gears and/or leverage mechanisms, typically operated by cams and/or by elastic elements, the latter being both of the linear and torsional kind.

DISCLOSURE OF THE INVENTION.

An object of the present invention is to make available a pincer, in particular for holding envelopes, which is extremely simple to build and, in particular, which has a reduced number of mechanical components. In particular, a pincer in accordance with the present invention has the goal of reducing the number of leverage mechanisms and gears currently present in prior art pincers.

Another object of the present invention is to provide a pincer which is universal, i.e. which, appropriately dimensioned, can be used to hold envelopes of any size. An additional object of the present invention is to propose a pincer which is reliable and economical to produce.

Said objects are fully achieved by the pincer, in particular for holding envelopes, of the present invention, which is characterised by the contents of the appended claims. BEST MODE FOR CARRYING OUT THE INVENTION.

These and other objects shall become more readily apparent from the following description of a preferred embodiment illustrated, purely by way of non limiting example, in the accompanying drawing table in which: - Figure 1 shows a partially sectioned lateral view of a pincer in accordance with the invention, in an operative configuration for releasing an envelope; - Figure 2 shows a partially sectioned lateral view of the pincer shown in Figure 1, in an operative configuration for holding an envelope.

With reference to the figures, the pincer for holding envelopes in accordance with the present invention is globally designated with the number 1 and is preferably made of stainless steel.

The pincer 1 comprises a pair of gripping elements 2, 3, operating between an operative configuration for releasing the envelopes (Figure 1) and an operative configuration for holding the envelopes (Figure 2).

The pincer 1 is also provided with a support structure 4 for a first grip element 2. In particular, said support structure 4 has a guide 5 for cursor 6, whereon is fastened a second gripping element 3. In the illustrated example, both the cursor 6 and the guide 5 develop according to a same axis 100, substantially longitudinal, and have a preferably circular cross section.

In particular, the cursor 6 has an end portion 7, positioned externally to the guide 5, and an operative portion 8, or stem, inserted within the guide.

In the illustrated example, the second gripping element 3 is integrally connected to the cursor 6, in correspondence with its end portion 7. In particular, the gripping element 3 is positioned externally to the guide 5 and is in substantially offset position relative to the axis 100 of longitudinal development of the cursor 6.

The first gripping element 2 is integrally connected with the support structure 4, in correspondence with its end 11. Specifically, the first gripping element 2 is positioned externally to the guide 5 and is substantially offset relative to the longitudinal axis 100 thereof.

With reference to the figures, to make the gripping elements 2, 3 offset relative to the longitudinal axis 100, each of them is installed on respective plates 22,33 and integrally fastened therewith by means of bolts 42, 43. In new and absolutely original fashion, the cursor 6 moves with rotary-translatory motion within the guide 5, in order to move the gripping elements 2,3 closer to and farther away from each other.

In the preferred embodiment, to activate the rotary-translatory motion of the cursor 6 are employed means which are appropriately positioned both on the cursor and within the guide 5.

Specifically, within the guide 5 is housed an abutment element 9 which co-operates with a groove 10 having at least a curvilinear segment 10a, wound on a lateral surface of the stem 8 of the cursor 6. In the illustrated embodiment, the abutment element 9 is preferably a pin having substantially circular cross section. The groove 10, coming in sliding contact with the pin 9, substantially serves as a cam, inducing the rotary-translatory motion of the cursor 6.

In the preferred embodiment, the groove 10 has a curvilinear development able to cause a rotation of the cursor 6 by about 90° about its own longitudinal axis 100. Specifically, the groove 10 has a helical development with a predetermined pitch, preferably such as to allow an advance of the cursor 6 by about 60 millimetres with a complete revolution (i.e. an angle of 360°) of the cursor 6 about its own longitudinal axis 100. However, since in the preferred embodiment the groove 10 has a curvilinear development the rotation of cursor 6 about its own longitudinal axis 100 is about 90°, the cursor advances by about 15 millimetres. In the illustrated example, the groove 10, in addition to having a curvilinear and substantially helical segment 10a, also has a rectilinear segment 10b with a length of about 10 millimetres. Said rectilinear segment 10b assures greater precision when gripping the envelopes and prevents any improper positioning. In the illustrated embodiment, the gripping elements 2,3 are constituted by a pair of buffers, made of rubber.

In operative conditions, the pincer 1 is associated to means for actuating the cursor 6, to enable the groove 10 to interact with the pin 9, to induce the rotary-translatory motion of the cursor 6 and to allow the gripping elements 2,3 to move closer/farther away. In the preferred embodiment, said means for actuating the cursor 6 are obtained by means of a pneumatic cylinder defined by the guide 5 itself and by a portion 6a of the cursor 6, which acts substantially as a piston. Specifically, the portion 6a of the cursor divides the guide 5 into two chambers 5a,5b, within which is alternatively sent pressurised air to induce the sliding of the cursor 6 within the guide 5. The operation of the invention is as follows. The pressurised air sent into a first chamber 5 a thrusts the cursor 6 within the guide 5, in such a way that the groove 10 interacts with the pin 9, which, following the profile of the groove, determines a rotary-translatory motion of the cursor 6 and hence of the gripping element 3. Once the cursor 6 has completed a rotation of about 90° about its longitudinal axis 100 and as substantially reached the end of its travel within the guide 5 (Figure 2), the gripping element 3 is in contact with the corresponding gripping element 2 integral with the support structure 4. In this way, the gripping elements 2, 3 are able to grip and firmly to hold an envelope previously interposed between them. To release the envelope, it is sufficient to send pressurised air into the second chamber

5b, in such a way that the cursor 6 is actuated in the opposite direction. The gripping element 3 thereby moves away from the element 2 and simultaneously rotates by effect of the interaction between the groove 10 and the pin 9. The invention achieves important advantages. First of all, a pincer according to the invention is extremely simple to build and has a reduced number of mechanical components. In particular, such a pincer requires no wheel mechanisms, lever mechanisms and/or transmissions, unlike prior art pincers. Secondly, the rotary-translatory motion of the cursor 6 (and hence of the gripping element 3 integral therewith), together with the offset of the gripping elements 2,3 relative to the longitudinal axis 100 of the guide 5, enables easily to release an envelope from the action of the gripping elements.

An additional advantage of the present invention is that such a pincer is universal, i.e. it can be employed to hold envelopes of any size. Advantageously, a pincer according to the present invention is economical to produce and reliable.

Claims

CLAIMS 1. A pincer (1), in particular for holding envelopes, comprising at least a pair of gripping elements (2,3) operating between a first operative configuration for holding the envelopes and a second operative configuration for their release, characterised in that it comprises: a support structure (4) for a first (2) of said gripping elements (2,3), said support structure (4) having at least a guide (5); a cursor (6) provided with a second gripping element (3) and movable with rotary-translatory motion within the guide (5), to move the gripping elements (2,3) closer to and farther away from each other; and means associated to the guide (5) and to the cursor (6) to activate the rotary- translatory motion of the cursor (6) itself.

2. A pincer as claimed in claim 1, characterised in that said means for activating the rotary-translatory motion of the cursor comprise: an abutment element (9) housed in the guide (5); a groove (10) having at least a curvilinear segment (10a) wound on an operative portion (8) of the cursor (6) inserted within the guide (5), said groove (10) being in sliding contact with said abutment element (9) and serving substantially as a cam.

3. A pincer as claimed in claim 2, characterised in that said abutment element (9) is a pin having a substantially circular cross section. 4. A pincer as claimed in claim 2, characterised in that said groove (10) has at least a second, substantially rectilinear segment (10b). 5. A pincer as claimed in claim 1 , characterised in that each of said cursor (6) and said guide (5) develops according to a substantially longitudinal axis (100). 6. A pincer as claimed in claim 5, characterised in that said second gripping element (3) is integrally connected with the cursor (6) in correspondence with its end (7) which is external to the guide (5) and in substantially offset position relative to said longitudinal axis (100). 7. A pincer as claimed in claim 5, characterised in that said first gripping element (2) is integrally connected in proximity to an end (11) of said support structure

(4), in a position that is external to the guide (5) and substantially offset relative to said longitudinal axis (100) of the guide (5). 8. A pincer as claimed in claim 2, characterised in that said curvilinear segment (10a) of the groove (10) has a substantially helical development able to cause a rotation of the cursor (6) by about 90° about its longitudinal axis (100) of development. 9. A pincer as claimed in claim 1, characterised in that each gripping element (2,3) comprises at least a buffer. 10. A pincer as claimed in claim 1, characterised in that it is associated to means for actuating the cursor (6). 11. A pincer as claimed in claim 9, characterised in that said means for actuating the cursor (6) comprise: at least a pneumatic cylinder; at least a piston, slidably inserted within said cylinder. 12. A pincer as claimed in claim 11, characterised in that the pneumatic cylinder is defined by said guide (5) and the piston is defined by a portion (6a) of said cursor (6).