WO1988003078A1

WO1988003078A1 - Tool for folding a plate member projecting at an angle from a surface, especially a locking tab for containers of plywood

Info

Publication number: WO1988003078A1
Application number: PCT/SE1987/000500
Authority: WO
Inventors: Kurt Moberg
Original assignee: Kurt Moberg
Priority date: 1986-10-27
Filing date: 1987-10-27
Publication date: 1988-05-05
Also published as: SE455055B; SE8604574L; SE8604574D0; AU8175787A

Abstract

A tool for folding a sheet-metal member projecting at an angle from a surface comprises a body (8) having a first part (9) for engaging said surface (4), and a second part (10) projecting at an angle to the first part of the tool body. With the body there is associated at least one arcuate guide (14) for guiding a push means (19) which is movable back and forth, in an arcuate path of movement about an edge portion which defines said surface and from which the sheet-metal member projects upwards. The sheet-metal member is foldable by the action of said push means, through at least about 180° from its upright position.

Description

TOOL FOR FOLDING A PLATS MEMBER PROJECTING AT AN ANGLE : FROM A SURFACE, ESPECIALLY A LOCKING TAB FOR CONTAINERS; OF PLYWOOD

Background of the invention

Plywood packings in the form of boxes comprise, in addition to four walls and a bottom, also a lid which can be sealed to the walls by means of locking tongues of sheet metal. More specifically, these sheet- metal tongues project upwards from the top edges of the walls and when the lid is put in place, the tongues are inserted through oblong slots provided in an edge fitting extending along the four side edges of the lid, such that locking can be effected by folding the tongues, with the lid correctly positioned, down through 180° from their upright state to a position in which they engage the outer sides of the walls. Hitherto, such folding of the locking tongues has been performed manually with a hammer, which inter alia is most detri¬ mental to the working environment. Thus, there are often many people present on the premises where the box-sealing work is carried out, and these people will be exposed to an extremely high noise level because of the hammer blows. Furthermore, working the locking tongues with a hammer means that the tongues are often folded in a non-uniform or incomplete fashion and that the tongues are deformed in such a way that reuse of the packing is made more difficult or even impossible. Also, people or objects coming in contact with the packing may easily be cut by such incompletely folded tongues .

Brief account of the inventive concept The present invention aims at overcoming the above- mentioned drawbacks by providing a suitable tool by means of which locking tongues or similar sheet-metal members can be folded in a rapid, efficient and silent manner. This is achieved by means of a tool which according to the inventive concept is characterized more specifically in that it comprises a body which has a first part for engaging said surface and a second part projecting at an angle to said first part, and which is associated with at least one arcuate guide for guiding a push means which is movable back and forth, in an arcuate path of movement about an edge portion which defines said surface and from which the sheet-metal member projects upwards, said sheet- metal member being foldable by the action of said push means, through at least about 180° from its up¬ right position.

Brief description of the accompanying drawings

In the drawings. Fig. 1 is a perspective view of the tool according to the invention shown together with a portion of a packing in the form of a box, Fig. 2 is a side view showing the tool in a starting position, Fig. 3 is a similar side view showing the tool during the final stage of a folding operation, and Fig. 4 is a cross-section taken along the line IV-IV in Fig. 2.

Detailed description of a preferred embodiment of the invention

In Fig. 1, reference numeral 1 generally designates a tool according to the invention and 2 designates a box, suitably of plywood, which has a number of walls 3 and a lid 4. Along the side edges of the lid, an edge fitting in the form of a sectional member of L-shaped cross-section is stationarily mounted and formed with longitudinal slots 6 for a respective one of a number of locking tongues 7 fixed to the outer side of the walls 3. In an initial position, these tongues project upwards substantially at right angles to the plane of the -lid 4 (i.e. in the extension of the plane of the walls 3). When the lid should be locked relative to the walls, each tongue 7 is folded down through 180° to a position in which it engages the outer side of the wall or, more precisely, of the fitting 5, as illustrated to the right in Fig. 1.

As appears more clearly from Figs. 2-4, the tool 1 has a body, generally designated 8, which includes a first part 9 engageable with the lid 4 and a second part 10 projecting at an angle to the.first part 9, suitably approximately at right angles thereto. The body 8 is formed with a substantially circular arc- shaped recess 11 defined by two spaced-apart side walls 12, 12' which are dismountably fixed to the body, e.g. by hexagon socket screws 13 (see also Fig. 1). A guide groove 14, 14' is milled or otherwise counter¬ sunk in the inner side of each of the walls 12, 12'. The grooves 14, 14' are arcuate at their forward end and merge rearwards into a substantially rectilinear portion extending not only along a certain part of the dismountable side walls 12, 12' but also along parts of wall portions which are fixedly associated with the body part 9 and define a substantially pa- rallelepipedal recess 11' in the body part 9. As ap- pears from Fig. 2, the guide groove 14 has a radius which, in conjunction with the straight portion of the groove, is relatively large and thereafter suc¬ cessively decreases in the direction of the lower, rearwardly directed end of the groove.

The body 9 is further connected to a suitably compressed air-operated piston and cylinder assembly, generally designated 15, having a piston rod 16 which is movable back and forth. The free end of the piston rod 16 is hingedly connected to a link 17, in. turn connected to two rollers or rolling means 18, 19 the leading one of which serves as push means for folding the sheet-metal tongue 7. As best seen in Fig. 4, the rolling means 19 (like the rolling means 18) has two spaced-apart wheels 20, 20' which are rotatably mounted on a common pivot pin 21 the opposite ends of which project from the opposite ends of the rolling means and each engage in one of the guide grooves 14, 14". Between the rolling means 18 and the rolling means 19, on the one hand, and the main link 17, on the other hand, there are provided intermediate links 22, 23 which, when the piston rod 16 is advanced in the manner shown in Fig. 3, allow the rolling means and the main link 17 to move in relation to each other and to follow the arcuate path of movement defined by the guide grooves 14, 14'. In this context, it should be pointed out that both the rolling means 18 and the main link 17 have hinge pins, engaging in the guide grooves, of the same type as the pin 21 of the leading rolling means 19.

In the transition between the two body parts 9 and 10, there is provided an L-shaped recess 24 in which the edge fitting 5 of the lid 4 can be accom¬ modated. It should also be noted that each sheet-metal or locking tongue 7 has a width which is at least slightly less than the smallest distance between the two side walls 12, 12' so as to provide sufficent room for the tongue between these walls.

At the rear end of the upper, horizontal portion of the L-shaped recess 24, there is formed a suitably sharp-edged projection 25 for abutting against the rear edge of the edge fitting 5, thus forming an abut¬ ment the function of which will be described in more detail hereinbelow.

The body part 9 is hingedly connected to an operat¬ ing part 26 in the form of a handle which when pressed against the body part 9 actuates a control valve 27 for controlling the supply of compressed air to the piston and cylinder assembly 15. In practice, this assembly may either be of the single-acting type and have a mechanical spring for returning the rolling means 18, 19 from an active to an inactive position, or be of the double-acting type, where the rolling means are pneumatically advanced and retracted.

Operation and advantages of the inventive tool

When a locking tongue should be folded, the tool 1 is applied with the tongue located in the space defined between the side walls 12, 12' and with the projection 25 abutting against the rear edge of the edge fitting 5 of the lid 4. When the control valve 27 is activated by the depression of the handle 26 in the manner shown in Fig. 3, the piston rod 16 is moved out of its cy¬ linder, whereby the leading rolling means 19 is applied against the tongue 7 and' progressively bends it from its upright state (Fig. 2) down through 180° to its folded state shown in Fig. 3. By a suitable selection of the curvature of the guide grooves 14, 14' and the diameters of the rolling means, not only the lead¬ ing rolling means 19 but also the following rolling means 18 will assist in distinctly folding the tongue, the leading rolling means 19, during its contact with the tongue, rolling along the tongue to the outer end thereof, and the following rolling means 18 acts on the tongue 7 during the final phase of the folding operation. When the leading rolling means 19 approaches the end^' of the arcuate guide formed by the grooves 14, 14', the tool is subjected to a force tending to move the tool in its entirety in an outward direc¬ tion away from the lid 4 and the edge fitting 5. This force is however taken up by the projection 25 serving as an abutment engaging behind the edge fitting and retaining the tool in position without the operator having to use bodily force to counteract the tendency of displacement of the tool.

In practice, the entire folding operation described above can be performed in an extremely rapid and silent manner by a simple advancing movement of the piston rod used.

Possible modifications of the invention

The invention is of course not restricted only to the embodiment described above and illustrated in the drawings. Thus, it is conceivable, for instance, to replace the rolling means by other push means for folding the tongue, it being also conceivable to use other means for advancing the push means than precisely a piston and cylinder assembly. In the case where the push means, as is preferred in practice, consists of a rolling means, it may consist of a single roller instead of the double rollers as exemplified in the drawings. Further, it is possible to design the guides other than as grooves.

Claims

1. A tool for folding a sheet-metal member, espe¬ cially a locking tongue on a plywood packing, which projects at an angle from a surface thereof, c h a ¬ r a c t e r i z e d in that it comprises a body (8) which has a first part (9) for engaging said surface (4) and a second part (10) projecting at an angle to said first part, and which is associated with at least one arcuate guide (14, 14' ) for guiding push means (19) which is movable back and forth, in an arcuate path of movement about an edge portion which defines said surface and from which the sheet-metal member (7) projects upwards, said sheet-rmetal member being foldable by the action of said push means, through at least about 180° from its upright position.

2: Tool as claimed in claim 1, c h a r a c t e r ¬ i z e d in that the push means consists of at least one roller (19) mounted on a pivot pin (21) the opposite ends of which project from the opposite ends of the roller and engage in two grooves (14, 14') forming said guide and designed or formed in two separate side walls (12, 12') of the tool body (8).

3. Tool as claimed in claim 2, c h a r a c t e r - i z e d in that the roller (19) of the push means is movable at least forwards towards the sheet-metal member (7) by means of a suitably compressed-air ope¬ rated piston and cylinder assembly (15) whose piston rod (16) is connected to the roller (19) of the push means by the intermediary of a number of links (17, 18) articulated to each other by hinge pins which, like said roller pin (21), engage in said guide grooves (14, 14' ).

4. Tool as claimed in any one of the preceding claims, c h a r a c t e r i z e d in that there is provided in the transition between the first and the second part (9, 10) of the tool body an L-shaped recess (24) for accommodating an edge fitting (5), also of L-shaped cross-section, of a plywood packing or the like.

5. Tool as claimed in claim 4, c h a r a c t e r - i z e d in that there is provided at the end of the portion of the L-shaped recess (24) which is associated with the first body part (9 ) , a suitably sharp-edged projection (25) for engaging against the rear edge of said edge fitting (5) so as to form an abutment preventing the tool from being displaced when the push roller (19), while folding the sheet-metal member (7), approaches the end of the arcuate guide (14, 14*).