WO1992000841A1

WO1992000841A1 - A crate and a mould therefor

Info

Publication number: WO1992000841A1
Application number: PCT/SE1991/000491
Authority: WO
Inventors: Jan Landqvist
Original assignee: Boxett Materialhantering Ab
Priority date: 1990-07-12
Filing date: 1991-07-12
Publication date: 1992-01-23
Also published as: SE9002426D0

Abstract

A plastic crate for bottles has an opening in the sidewall, the wall above the opening forming a handle. The lower bearing surface (23, 24) of the handle facing towards the hand is widened by an inward bulge (24) in the crate wall above the wall opening. It has been possible to form the inward bulge since the mould used for the crate has a matrix core which extends up on the inside of the crate wall and forms a lower mould surface for said inward bulge of the handle. The core (51) forms an opening through the bottom of the crate and the crate bottom (13) must be planned taking into account the opening for the core (51).

Description

A crate and a mould therefor

The present invention relates to an injection-moulded plastic crate to hold bottles, with a handle for carrying it, and a mould for producing said crate, as described in the preamble to the appended independent claims.

When injection-moulding plastic crates for bottles, the mould space is defined by an upper mould half, the patrix, defining upwardly facing surfaces of the crate, a lower mould half, the matrix, defining downwardly facing surfaces of the crate, and lateral punches defining openings or recesses in the side walls of the crate. Usually optimal use of the bottom surface for bottles is strived for and a handle or grip is normally provided on each of two opposite walls of the crate, e.g. the end walls, by an opening being provided in the side wall close to the upper edge of the wall, allowing the remaining upper frame to be easily gripped by the hand.

One problem is that the resultant bearing surface of the handle, via which the load of the crate is transmitted to the carrier's hand, is usually only the same width as the wall thickness of the crate, said thickness being limited for reasons of space and to save material. The grips or handles in conventional crates are therefore uncomfortable.

An object of the invention is to present a crate with an improved grip, wider thatn the wall thickness of the crate, and being shaped to fit the hand, as well as possibly offering resilient adjustment to the shape of the hand.

Another object of the invention is to present a mould permitting simple manufacture of such a crate. The inven¬ tion and embodiments thereof are defined in the appended claims.

As is clear from the claims, the invention fundamentally comprises planning the bottom of the crate so that a space free from bottles is obtained close to the wall in which the handle is to be arranged and opposite the proposed location of the handle.

The bottom construction of the crate is designed so that an opening can be made through the bottom of the crate at said free spaces.

A core on the matrix extends through the opening up to the lower surface of the handle. The patrix is provided with a mould part defining a counter surface to the upper surface of the core. An external punch is provided with a groove, the lower surface of which connects with the upper surface of the core. The punch groove defines a lower flange which constitutes the lower bearing surface of the handle. The punch may also be provided with a nose to give the upper part of the crate wall a uniform thickness in cooperation with corresponding mould parts in the upper surface of the core and the patrix. The bottom of the groove may be on a plane defining the outer surface of the crate wall, and the part of the wall located above the wall opening is therefo¬ re provided with an upper and a lower outwardly directed flange connected by a mid-section, the lower, inner part of which bulges out over the punch.

Alternatively the punch may be arranged on the inside of the crate wall, i.e. horizontally movable on the patrix, thereby constituting the equivalent to the known mould part, in which case the upper frame of the crate in prin- ciple acquires a profile facing in the opposite direction. By means of the invention the inner, lower part of the grip can be rounded, making it comfortable to hold. An important advantage of the invention is that the bearing surface of the grip is considerably larger than the thickness of the crate wall.

The invention will be described in the following with reference to an embodiment illustrated schematically.

Figure 1 shows schematically a crate for bottles from above.

Figure 2 shows schematically a detail of the crate accor¬ ding to Figure 1.

Figure 3 shows an end view of the crate, taken along the line III - III in Figure 2.

Figure 4 shows a partial section through the crate, taken along the line IV - IV in Figure 2, and a corresponding schematically illustrated mould in which the crate is manufactured.

Figure 5 shows a section corresponding to Figure 4, through a different embodiment.

Figure 1 shows a crate 1 arranged to receive bottles in positions defined by recesses 2 in the bottom 13 of the crate.

The recesses 2 are arranged in three parallel rows 4, 5, 6 comprising two outer rows 4 and 6 with three recesses 2 each, and a central row 5 with two recesses 2. The recesses in the central row 5 are displaced by the width of half a recess in relation to those in the outer rows 4, 6. A trapezoidally shaped area 12 is thus obtained at the short ends of the rectangular bottom of the crate, between the short wall 11 and adjacent recesses 2.

According to the invention an opening is made through the crate bottom 13 within this area 12, close to the inner surface of the crate wall. The crate wall 11 is provided with a side opening 15 (see Figure 3), defining an upper frame 21 which can be used as a handle. According to con- ventional technology, the grip 21 has a width correspon¬ ding to the thickness of the wall 11. According to the invention, the frame 21 comprises an upper 21 and a lower horizontal flange 23, connected by a mid-section 24. Accor- ding to the invention at least the lower part of the mid- section 24 is bent in over the triangular opening 12 in the crate bottom. The ends of the bent-in mid-section 24 can be connected via mid-sections 25 of the wall to the outer, unbent parts of the vertical mid-section joining the flang- es 21, 23.

From Figure 4 it can be seen that the mould comprises a matrix defining downwardly facing surfaces of the crate, a patrix defining upwardly facing surfaces of the crate, and side punches defining the outer surfaces of the crate walls and openings through the crate walls.

A prominent feature of the invention is that the matrix 50 is provided with a core 51 extending through the trapezoi- dally shaped space between the short wall 11 of the crate and three adjacent recesses 2 for bottles (see Figure 2).

The core 51 thus produces an opening through the crate bottom, close to the short wall 11, and extends upwardly to the level of the lower surface of the handle. The handle is conventionally defined by a side punch 34 which forms an opening through the crate wall, thus giving the bearing surface of the handle a width corresponding to the thick¬ ness of the crate wall 11. In the embodiment shown, the punch 34 is provided with a groove 33 which defines a lower handle flange 23 within the wall thickness of the crate wall.

Besides mould parts defining the bottom and upper frame of the crate, the patrix 40 also has a mould part 41 corre¬ sponding to the upper part of the core 51 in order to ensure uniform material thickness in the upper wall part 21 of the crate.

Above the side opening 15 of the crate wall, the wall and handle 21 consist of a thin, solid wall section 21 having upper and lower outwardly directed flange parts 22, 23. A mid-section 24 extends between these flanges, the lower part of which bulges over the trapezoidally shaped opening 12 in the crate bottom, i.e. over the upper surface of the core 51. The punch 34 has a nose 31 which defines the outside of the mid-section 24, and also a groove 32 for the upper flange 22.

The ends of the bent-in part 24 of the handle may be joined to the mid-section of the wall outside the outwardly bul¬ ging part 24 via the connecting piece 25.

Although the design of the crate bottom shown here particu¬ larly facilitates producing a wider bearing surface for the handle, it should be clear that other embodiments are possible. The essential point is that when planning the crate bottom, a space is left on the inside of the wall in which the handle is to be arranged, in which space a through-opening can be arranged for a core defining the part of the bearing surface of the handle which bulges to the inside of the wall.

Figure 5 shows an embodiment in which the profile of the upper frame 21 is turned the other way. The outside of teh frame is defined by a fixed mould part 500 and the wall opening by a side punch 340. The punch 510 extending through the bottom opening of the crate corresponds to the punch 51. The patrix 400 corresponds to the patrix 40 but has an internal side punch 310 which defines the undercut inner side of the upper frame 21 and the upper side of the widened grip flange, the lower side of which is substanti¬ ally defined by the core 510. The internal punch 310 is provided with grooves 311 forming reinforced fins for the grip flange. 300 denotes a space in the patrix for the punch 310.

Claims

C l a i m s

1. An injection-moulded plastic crate to hold bottles, said crate comprising a bottom (13) and at least two oppo- site walls with openings (15) defining handles (21) with a downwardly facing bearing surface (23), the width of which corresponds to the thickness of the crate wall (11), w h e r e i n the handle has an extended bearing surface extending inwardly past the inner defining surface of the crate wall beneath, and wherein the bottom of the crate has a through opening which at least corresponds to said ex¬ tended bearing surface of the handle, immediately beneath said extended surface.

2. A mould for injection-moulding a plastic crate, said crate being open at the top and having a bottom (13) and side walls (11) with openings through the walls (11) to provide handles (21) with a bearing surface the width of which corresponds to the thickness of the crate wall, said mould comprising a matrix (50) defining downwardly facing surfaces of the crate, a patrix (40) defining upwardly facing surfaces of the crate, and side punches (34) defi¬ ning surfaces of the side walls of the crate and any ope¬ nings through the side walls, w h e r e i n the matrix (50) has a core (51) extending through the bottom of the crate up to the inner surface of the side wall in which the handle is to be arranged, the upper surface of the core (51) defining a horizontal enlargement of the bearing surface of the handle (21) inside the inner surface of the crate wall (11) beneath, within the contour of the core cross-section.

3. A mould as claimed in claim 2, w h e r e i n the patrix (40) is provided with a counter surface (41) corre- sponding to the upper surface of the core (51), said coun¬ ter surface defining a junction between the inner part of the handle and the inner surface of the crate wall (11) above the downwardly facing bearing surface of the handle.

4. A mould as claimed in claim 2 or 3, w h e r e i n the side punch (34) has a nose which, together with the upper surface of the core (51) and the counter surface (41) of the patrix, defines a uniform wall thickness for the handle and the part of the crate wall located above the opening (15).

5. A mould as claimed in claim 2 or 3, w h e r e i n the side punch is applied on the patrix and forms both the upper surface of the flange of the handle located inside the inner wall surface of the crate, and also a recess on the inside of the crate wall.

6. A mould as claimed in claim 5, w e r e i n the side punch is provided with vertical grooves oriented in the direction of movement of the punch which form reinfor¬ cing fins between the crate wall and the flange of the handle.