DEVICE FOR DOSING BULK MATERIAL

Abstract

A device for dosing bulk material, in particular plastic granules, for machines that process plastic granules, in particular for injection moulding machines. The invention provides a bulk material feed (1), a material hopper (3) formed by multiple, preferably four, individually removable material hopper containers (2) and arranged under the bulk material feed (1) and ending in a dosing base device (4), and, optionally, a weighing container with a scale in the dosing base device (4). The individual material hopper containers (2) are arranged on a support spider (5) and the support spider (5) is formed by support spider plates (11) arranged vertically and perpendicular to one another. The support spider is mounted on the housing of the dosing base device (4). The support spider (5) has a height (h), which is at least the height (h.sub.1) of the material hopper container (2), which extends over the dosing base device (4), and corresponds to the immersion depth (h.sub.2) of the material hopper (3) into the dosing base device (4). A material hopper cover (6) is provided on the end of the support spider (5) facing away from the dosing base device (4).

Claims

1. A device for dosing bulk material, in particular plastic granules, for machines that process plastic granules, in particular for injection moulding machines, wherein a bulk material feed, a material hopper formed by multiple, preferably four, individually removable material hopper containers and arranged under the bulk material feed and ending in a dosing base device, and, optionally, a weighing container with a scale in the dosing base device is provided, and said individual material hopper containers are arranged on a support spider and the support spider is formed by support spider plates arranged vertically and perpendicular to one another and the support spider is mounted on the housing of the dosing base device, characterized in that the support spider (5) has a height (h), which is at least the height (h1) of the material hopper container (2), which extends over the dosing base device (4), and corresponds to the immersion depth (h2) of the material hopper (3) into the dosing base device (4) and that a material hopper cover (6) is provided on the end of the support spider (5) facing away from the dosing base device (4).

2. Device according to claim 1, characterized in that the metal hopper cover (6) extends over the material hopper (3) or over individual material hopper containers (2).

3. Device according to claim 1, characterized in that the metal hopper cover (6) comprises openings (13) for feeding the bulk material from the bulk material feed (1) into the material hopper container (2).

4. Device according to claim 1, characterized in that material hopper cover (6) comprises an immersion pipe (7) in the direction of the dosing base device (4) for feeding the bulk material.

5. Device according to claim 1, characterized in that the material hopper (3) composed of multiple individual material hopper containers (2) is tapered, preferably pyramidal or conical, in the direction of the weighing container.

6. Device according to claim 1, characterized in that the sides (9) of each material hopper container (2) forming the outer lateral surface of the material hopper (3) are designed higher, namely by at least the immersion depth (h2) of the material hopper (3) into the dosing base device (4), in the area of the bulk material feed (1) than the sides (10) adjacent to the support spider (5) on the inside.

7. Device according to claim 1, characterized in that the sides (9) of each material hopper container (2) forming the outer lateral surface of the material hopper (3) in the area of the bulk material feed (1) are formed by sheet metal faceplates having a height which corresponds at least to the immersion depth (h2) of the material hopper (3) into the dosing base device (4).

8. Device according to claim 1, characterized in that fastening brackets (8) for the material hopper containers (2) are provided to the support spider (5).

Description

[0023] The invention is explained in more detail on the basis of the embodiment illustrated in the figure.

[0024] The figures show:

[0025] FIG. 1 a section through the device and

[0026] FIG. 2 a support spider with a material hopper cover and a dosing base device.

[0027] The invention for dosing bulk material, in particular plastic granules, for machines that process plastic granules, in particular for injection moulding machines, has a modular design. The invention according to FIG. 1 comprises a bulk material feed 1, for example a material separator, a material hopper 3 formed by multiple, preferably four, individually removable material hopper containers 2 and arranged under the bulk material feed 1. Said material hopper 3 ends in a dosing base device 4. Optionally, a weighing container with a scale in the dosing base device is provided. The individual material hopper containers 2 are arranged on a support spider 5, whereby the support spider 5 is formed by support spider plates 11 arranged vertically and perpendicular to one another and the support spider 5 is mounted in the dosing base device 4.

[0028] The support spider 5 has a height h, which is at least the height h.sub.1 of the material hopper container 2, which extends over the dosing base device 4, and corresponds to the immersion depth h.sub.2 of the material hopper container 2 into the dosing base device 4. A material hopper cover 6 is provided on the end of the support spider 5 facing away from the dosing base device 4. The metal hopper cover 6 extends over the material hopper 3. Naturally, it may also just extend over individual material hopper containers 2. Furthermore, the metal hopper cover 6 comprises openings 13 for feeding the bulk material from the bulk material feed 1 into the material hopper container 2.

[0029] Furthermore, the material hopper cover 6 comprises an immersion pipe 7 in the direction of the dosing base device 4 for feeding the bulk material. Said immersion pipe 7 serves for defining the height of the bulk cone in the material hopper container 2.

[0030] The individual material hopper containers 2 are held or stabilized in their position, in particular also if a vertical, upwardly directed opening force is exercised on the dosing valve, by fastening brackets 8.

[0031] The sides 9 of each material hopper container 3 forming the outer lateral surface of the material hopper 3 are designed higher, namely by at least the immersion depth h.sub.2 of the material hopper 3 into the dosing base device 4, in the area of the bulk material feed 1 than the sides 10 adjacent to the support spider 5 on the inside. Naturally, sheet metal faceplates could also be used instead of the higher sides 9.

[0032] For easier handling, each material hopper container 2 may comprise two handles. For more convenient cleaning and also for visual check, each material hopper container 2 may comprise an inspection glass. Furthermore, the material hopper container 2 may consist of wear-resistant stainless steel.

[0033] The material hopper 3 composed of multiple individual material hopper containers 2 is tapered, preferably pyramidal or conical, in the direction of the weighing container.

[0034] Each material hopper container 2 comprises a dosing valve at its lower end in the dosing base device 4. A weighing container connected with a scale may be arranged underneath, and a mixer underneath the weighing container. A platform load cell may be provided as scale and a ball mixer as mixers. The platform load cell may be connected with the dosing valve through a control unit.

[0035] The dosing valve may be designed as a self-closing dosing valve, whereby the dosing valve is opened through a pneumatic cylinder, preferably arranged on the dosing base device 4.

[0036] In the dosing device shown above, different amounts of different plastic granules are introduced in batches according to freely adjustable formulations. Each individual type of plastic granulate, such as for example new material, main batch, additive and/or material to be ground, is successively passed through the dosing valve into the weighing container from a material hopper container 2, weighed in the weighing container and the formulation is subsequently mixed in the ball mixer.

[0037] FIG. 2 shows the support spider 5, which is formed by rectangular, vertical plates 11. To save weight, these plates 11 may comprise recesses 12. The support spider 5 is mounted in the dosing base device 4. The material hopper cover 3 with openings 13 for feeding the bulk material is provided on the end facing away from the dosing base device 4.

[0038] The front material hopper containers 2 are lifted out in the graphically shown FIG. 2, hence not drawn, in order to illustrate the plate structure of the support spider 5. The rear material hopper container 2 is certainly shown, however.