WO2001047683A1

WO2001047683A1 - Injection mold key lock

Info

Publication number: WO2001047683A1
Application number: PCT/US2000/035462
Authority: WO
Inventors: Norman H. Cohan; Endido A. Gomez; Eugene L. Foltuz
Original assignee: Security Plastics, Inc.
Priority date: 1999-12-29
Filing date: 2000-12-28
Publication date: 2001-07-05
Also published as: AU2741001A

Abstract

A universal locking mechanism for injection mold machines for use with any type of mold machine comprising a mold plate (12) with a plurality of mold cavities (14), and a plurality of locking channels (16), a plurality of elongated locking bars (18), each locking bar (18) comprising a plurality of locking notches (20) and a plurality of locking slots (22), a plurality of interchangeable mold tools (30), each mold tool (30) having mold tools (30) dimensioned to receive each locking notch (20), a plurality of tool locking notches (34) dimensioned to fit into the locking slots (22) and a tool locking channel (36), and a means to slideably move the locking bar from a first open locking position to a first closed locking position or from a second closed locking position to a second open locking position. Alignment of the locking notches (20) within the tool slots (32) and the tool locking notches (34) within the locking slots (22) permits movement of the locking bar (18) within the toll locking channel (36) resulting in misalignment of the locking slots (22) with the tool notches (32) and the locking notches (20) with the tool slots (32) thereby securing the mold tools (30) to the mold plate (12). Means to slideably move the locking bar may be manual or automated.

Description

INJECTION MOLD KEY LOCK

FIELD OF INVENTION

The present invention relates generally to a locking device for injection mold systems, specifically for rigidly fixing interchangeable mold tools.

BACKGROUND OF THE INVENTION

This invention is directed to injection mold systems, and more specifically, heterocavity injection mold systems.

An object of this invention is to provide a quick-change mechanism to interchange one or more molds between production cycles. Previous attempts have been made to provide a mold locking mechanism such as described in U.S. Patent No. 4,202,522 to Hanas et al. ('522 patent); U.S.

Patent No. 4,472,127 to Cyriax et al. ('127 patent); U.S. Patent No. 4,473,346 to

Hehl ('346 patent); U.S. Patent No. 4,500,274 to Cyriax et al. ('274 patent); U.S.

Patent No. 4,500,275 to Ruhl ('275 patent); U.S. Patent No. 4,678,158 to Brock (' 158 patent); U.S. Patent No. 4,737,093 to Hori et al. ('093 patent); U.S. Patent No.

4,810,182 to Groll ('182 patent); U.S. Patent No. 4,881,891 to Luther ('891 patent);

U.S. Patent No. 4,929,166 to DiSimone et al. ('166 patent); U.S. Patent No.

5,012,568 to DiSimone et al. ('568 patent); U.S. Patent No. 5,044,921 to Micelli et al. ('921 patent); U.S. Patent No. 5,114,335 to Tinsley ('335 patent); U.S. Patent No. 5,494,435 to Vandenberg ('435 patent); and all of which are incorporated herein by reference.

The '522 patent to Hanas et al. describes a device for accepting various sizes of molding die inserts in an injection mold machine using a pair of injection die support frames to hold either injection molding die insert fitting directly into corresponding recesses in fronting faces of the dies support frames or second injection molding die insert combined with respective injection die insert adapters fitting into the recesses in the die support frames.

The '127 patent to Cyriax et al. describes an injection-molding machine whose mold-carrying plates are provided with quick-release locking devices whereby a carriage is displaceable along the machine and has roller conveyors and a device for drawing a mold from the machine onto the roller conveyor or pushing a mold from the roller conveyor onto the machine.

The '346 patent to Hehl describes a mechanism for the clamping attachment of interchangeable injection molds to the mold base whereby a plurality of clamping plungers in axial guide bores of the mold base engage the injection molds wherein each clamping plunger has a clamping nose coupled to a clamping shoulder of an oversized back plate of the mold base.

The '274 patent to Cyriax et al. describes a rapid-change system for injection-mold machines whereby a pair of adapter plates are secured to the respective mold parts which engage in guides of the mold-carrying plates of the machine. Locks on the mold carrying plates hold the adapter plates in position and the plates can be provided with service fittings which interconnect and disconnect upon insertion and removal of the mold together with the respective adapter plates.

The '275 patent to Ruhl describes an injection molding machine having opposed station and moveable plates adapted to receive, mount and secure a sectional plastic mold having stationary moveable clamp plates.

The '158 patent describes an injection mold assembly including a plurality of locking bars for securing the mold sidewalls in a mold closed position. The locking bars project from one mold plate and are positioned outwardly of the mold sidewalls and include ends adapted to engage the other mold plate when the mold is closed and to function as wedges preventing outward movement of the mold sidewalls.

The '093 patent describes a die locking mechanism for a molding apparatus including stationary and movable die assemblies, including a stop bar movable back and forth with respect to the stationary frame structure in a direction parallel with the direction of movement of the movable die assembly, and a locking member rockable between first and second angular positions above a fixed pivot axis.

The '182 patent describes a quick changing and quick gripping device that includes at least one locking bar which is movable mounted in a mold half and which automatically engages a locking bar engagement means mounted in the other mold half by means of a biasing force, such as a spring.

The '891 patent describes a mold assembly having a support member which is moveable in a direction of travel both toward and away from an end plate and supporting individual mold side walls which are slideably moveable along a path of travel from a mold open to a mold closed position; and a locking member is selectively moveable into movement restraining relation relative to the individual mold side walls thereby positioning the individual mold sidewalls in the mold closed position.

The '166 patent describes a key/slot arrangement for facilitating installation and removal of a central mold portion. The key/slot arrangement includes nonuniform width key elements on frame members which support the central mold portion and non-uniform width slots in side portions of the central mold portion for engaging the key elements. Additionally, the '166 patent describes a rack/gear drive arrangement for insuring proper positioning of the mold elements at all times. The '921 patent describes a locking device mounted in the interior portions of a mold that allows the mold to be easily locked and unlocked, and prevents material from seeping out from the joint between the two mold sections.

The '335 patent describes a mechanical locking mechanism for an injection mold for holding a core rod in place in the mold cavity to resist movement caused by the injection molding pressures. The '435 patent describes a positive internal latch lock for an injection mold having outer, intermediate, and inner plates movable between open and closed mold positions. The latch lock includes a mechanism for securing the outer and intermediate plates at a predetermined spaced distance when the mold is opened at a first parting line between the outer and intermediate plates.

Most of the above listed references describe a locking apparatus or injection molding machine that include a complex means to lock or secure mold tools to a mold machine. None of the devices described above describe a locking mold device that comprises an easy means to secure and release mold tools to and from a mold machine.

Consequently, there is a need in the art for an easy to use mold locking device.

There is a further need in the art for such a universal mold locking device that is easy to use and inexpensive to manufacture. SUMMARY OF INVENTION

The present invention solves significant problems in the art by providing a simple and easy means to secure interchangeable mold tools within a mold machine. The present invention is a locking mechanism for injection mold machines. In a preferred embodiment the locking mechanism comprises a mold plate having a plurality of mold cavities, a plurality of locking channels, a plurality of elongated locking bars, each locking bar having a plurality of locking notches, and a plurality of locking slots, a plurality of interchangeable mold tools, each mold tool having mold slots dimensioned to receive each locking notch, a plurality of tool locking notches dimensioned to fit into the locking slots and a tool locking channel, and a means to slideably move the locking bar from a first open locking position to a first closed locking position or from a second closed locking position to a second open locking position. Once each mold tool is inserted into each mold cavity, alignment of the locking notches within the tool slots and the tool locking notches within the locking slots permits movement of the locking bar within the tool locking channel resulting in misalignment of the locking slots with the tool notches and the locking notches with the tool slots thereby securing the mold tools to the mold plate. The locking mechanism further comprises a retainer plate and retainer key to provide further support for securing the mold tool into the mold plate. Means to slideably move the locking bar may comprise manually sliding the locking bar from a first open locking position to a first closed locking position or from a second closed locking position to a second open locking position. Alternate means to slideably move the locking bar comprises a movable sliding key plate, wherein the plurality of locking bars are fixed to the sliding key plate, a plurality of air cylinders, each air cylinder affixed to the sliding key plate by a connecting bar, wherein automated movement of the key plate results in the movement of the locking bars from the first open locking position to the first closed locking position or from the second closed locking position to the second open locking position.

An object of the present invention is to provide a simple method to secure and release mold tools in and from a mold machine without the need to dismantle the entire mold plate.

Another object of the present invention is to provide a universal locking device for use in all types of mold machines.

Another object of the present invention is to provide a simple locking device for use in mold machines that is inexpensive and simple to manufacture. These and other objects, features, and advantages of the present invention may be more clearly understood and appreciated from a review of the following detailed description of the disclosed embodiments and by reference to the appended drawings and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of the preferred embodiment of the locking device according the present invention.

FIG 2. is a perspective view of the mold plate of the locking device according to the present invention. FIG.3 is a bottom view of the mold plate of the locking device according to the present invention.

FIG. 4 is a cross sectional view along the line A- A of the locking channel of the locking device according to the present invention.

FIG. 5 is a view front view of a mold machine using the locking device according to the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

Referring initially to FIG. 1 of the drawings, in which like numerals indicate like elements throughout the several views, in a preferred embodiment the mold locking device of the present invention is referred generally as 10. As shown in FIG. 1 the mold locking device 10 comprises a mold plate 12 having a plurality of mold cavities 14, a plurality of locking channels 16, and a plurality of elongated locking bars 18, each locking bar 18 having a plurality of locking notches 20, and a plurality of locking slots 22, and a plurality of interchangeable mold tools 30, each mold tool 30 having a plurality of tool slots 32 dimensioned to receive each locking notch 20, a plurality of tool locking notches 34 dimensioned to fit into the locking slots 22, and a tool locking channel 36, and a means to slideably move the locking bar 18 from a first open locking position to a first closed locking position or from a second closed locking position to a second open locking position. The first and second open locking positions are positions in which the locking device 10 is unlocked ("open"). The first and second closed locking positions are positions in which the locking device is locked ("closed"), thereby securing each mold tool 30 to the mold plate 12.

Once each mold tool 30 is inserted into each mold cavity 14, alignment of the locking notches 20 within the tool slots 32 and the tool locking notches 34 within the locking slots 22 permits movement of the locking bar 18 within the tool locking channel 36 resulting in misalignment of the locking notches 20 with the tool slots 32 and the tool locking notches 34 with the locking slots 22 thereby securing the mold tools 30 to the mold plate 12. Misalignment of the locking notches 20 with the tool slots 32 and the tool locking notches 34 with the locking slots 22 prevents vertical movement of each mold tool 30 due to the obstruction of the locking notches 20 and the tool locking notches 34. The mold plate 12 further comprises a retainer plate 40 for further securing the mold tools 30 to the mold plate 12. The mold locking device 10 is inherent within the mold plate 12. However, as shown in FIG. 1, in order for the mold locking device 10 to function, the base of the mold tool 30 must be fabricated to have tool locking notches 34, tool slots 32 and tool locking channels 36. Similarly, the mold plate 12 must be fabricated to include locking notches 20, locking slots 22 and locking channels 16, dimensioned to fit into the corresponding tool slots 32 and tool locking notches 34, respectively. The types of mold machines that can be readily used with the present locking device include the Injection Molding Apparatus with Removable Hetero-Cavity Molding Tools, as shown in FIG. 5, and the Center Gating Injection Molding Apparatus with Removable Hetero-Molding Tools, which are the subject of patent applications Serial Nos. 09/223,854 and 09/224,264, respectively. Moreover, because the locking device 10 must be inherently manufactured within any injection molding machine, the present invention may be used in connection with virtually any injection molding machine, that comprises removable mold tools. The present invention may also be used to retrofit existing molding machines. FIG 2. shows a section of the mold plate 12 having a single mold cavity 14.

As shown in FIG. 2, the locking bar 18 protrudes out from the mold plate 12 at opposite sides of the mold plate 12, namely the side walls of the mold cavity 14.

Each mold tool 30 has two locking bars 18 located on opposite sides of the mold tool 30. FIG. 3 shows a bottom view of the mold plate 12 without the mold tool 30.

A cross sectional view along the line A-A, as shown in FIG. 4, shows the locking channel 16 of the locking mold device 10. As previously stated, the first or second open locking positions comprise alignment of the tool locking notches 34 within the locking slots 22, and the locking notches 20 within the tool slots 32. The foregoing alignment permits slideable movement of the locking bar 18 within the tool locking channel 36. Movement of the locking bar 18 results in the misalignment of the locking notches 20 with the tool slots 32 and the tool locking notches 22 with the locking slots 22 thereby securing the mold tool 30 to the mold plate 12. Vertical movement of the mold tool 30 from the mold plate 12 is restricted due to the misalignment of the tool locking notches 34 and locking notches 20. The foregoing comprises the first and second closed locking positions. Each mold tool 20 also has a plurality of retainer plates 40 and a plurality of retainer keys 42, each retainer plate 40 corresponding to the plurality of locking bars 18 located on opposite sides of each mold cavity 14. Means to slideably move the locking bar 18 from the first open locking position to the first closed locking position or from the second closed locking position to the second open locking position is also provided. Such means can be either manual or automatic (such as an air actuator). Horizontal movement of the locking bar 18 need only be slight, about approximately five eighths of an inch (5/8"). Due to such a slight movement, locking and unlocking an injection molding machine comprising the present locking device 10 provides a quick and easy method for interchanging mold tools.

As an example of the implementation of the present invention to a molding machine, FIG. 5 shows the locking device 10 as used with an Injection Molding Apparatus with Removable Hetero-Cavity Molding Tools. FIG. 5 shows the locking device 10 having an automated means to slideably move the locking bar 18 from the first open locking position to the first closed locking position or from the second closed locking position to the second open locking position. As shown in FIG. 5, the locking bars 18 are attached to a moving key plate 60. A plurality of air cylinders 62 are connected to the moving key plate 62 via a plurality of connecting bars 64. Movement of the moving key plate 60, by activation of the air cylinders 62, simultaneously moves each locking bar 18 from the first open locking position to the first closed locking position or from the second closed locking position to the second open locking position. As a result, activation of the air cylinders 62 simultaneously controls the locking and unlocking of each mold tool 30 to each mold plate 12.

Accordingly, it will be understood that the preferred embodiment of the present invention has been disclosed by way of example and that other modifications and alterations may occur to those skilled in the art without departing from the scope and spirit of the appended claims.

Claims

What is claimed is:

1. A locking mechanism for injection mold machines comprising: a mold plate having a plurality of mold cavities and a plurality of locking channels, each locking channel comprising an elongated locking bar having a plurality of locking notches and a plurality of locking slots; a plurality of interchangeable mold tools, each mold tool having a plurality of tool slots dimensioned to receive each locking notch, a plurality of tool locking notches dimensioned to fit into said locking slots and a tool locking channel; and a means to slideably move said locking bar from a first open locking position to a first closed locking position or from a second closed locking position to a second open locking position, whereby once each mold tool is inserted into each mold cavity, alignment of said locking notches within said tool slots and said tool locking notches within said locking slots permits movement of said locking bar within said tool locking channel resulting in misalignment of said locking slots with said tool notches and said locking notches with said tool slots thereby securing said mold tools to said mold plate.

2. The locking mechanism of claim 1, further comprising a retainer plate enclosed within said mold plate for securing said mold tool to said mold plate.

3. The locking mechanism of claim 1, wherein the means to slideably move said locking bar comprises manually sliding said locking bar from said first open locking position to said first closed locking position or from said second closed locking position to said second open locking position.

4. The locking mechanism of Claim 1, wherein said means to slideably move said locking bar comprises: a movable sliding key plate, wherein said plurality of locking bars are fixed to said sliding key plate; a plurality of air cylinders, each air cylinder affixed to said sliding key plate by a connecting bar, wherein automated movement of said key plate results in the simultaneous movement of said locking bars from said first open locking position to said first closed locking position or from said second closed locking position to said second open locking position.

5. A locking mechanism for injection mold machines comprising: a mold plate having a plurality of mold cavities and a plurality of locking channels, each locking channel comprising an elongated locking bar having a plurality of locking notches and a plurality of locking slots; a plurality of interchangeable mold tools, each mold tool having a plurality of tool slots dimensioned to receive each locking notch, a plurality of tool locking notches dimensioned to fit into said locking slots and a tool locking channel; a means to slideably move said locking bar from a first open locking position to a first closed locking position or from a second closed locking position to a second open locking position, wherein said means comprises manually sliding said locking bar from said first open locking position to said first closed locking position or from said second closed locking position to said second open locking position; and a retainer plate enclosed within said mold plate for securing said mold tool to said mold plate, whereby once each mold tool is inserted into each mold cavity, alignment of said locking notches within said tool slots and said tool locking notches within said locking slots permits movement of said locking bar within said tool locking channel resulting in misalignment of said locking slots with said tool notches and said locking notches with said tool slots thereby securing said mold tools to said mold plate.

6. A locking mechanism for injection mold machines comprising: a mold plate having a plurality of mold cavities and a plurality of locking channels, each locking channel comprising an elongated locking bar having a plurality of locking notches and a plurality of locking slots; a plurality of interchangeable mold tools, each mold tool having a plurality of tool slots dimensioned to receive each locking notch, a plurality of tool locking notches dimensioned to fit into said locking slots and a tool locking channel; a means to slideably move said locking bar from a first open locking position to a first closed locking position or from a second closed locking position to a second open locking position, wherein said means comprises a movable sliding key plate, wherein said plurality of locking bars are fixed to said sliding key plate, a plurality of air cylinders, each air cylinder affixed to said sliding key plate by a connecting bar, wherein automated movement of said key plate results in the simultaneous movement of said locking bars from said first open locking position to said first closed locking position or from said second closed locking position to said first open locking position; a retainer plate enclosed within said mold plate for securing said mold tool to said mold plate, whereby once each mold tool is inserted into each mold cavity, alignment of said locking notches within said tool slots and said tool locking notches within said locking slots permits movement of said locking bar within said tool locking channel resulting in misalignment of said locking slots with said tool notches and said locking notches with said tool slots thereby securing said mold tools to said mold plate.