RU2397019C1 - Grinder - Google Patents

Abstract

FIELD: technological processes.

SUBSTANCE: invention relates to devices for grinding of materials and may be used in various industries, in particular food, fish, chemical, processing industries, agriculture, etc., to process hard-to-grind materials and products. Grinder comprises cylindrical vessel with cover and discharge window covered with deck in the form of separating plate with through holes, vertical supply nozzle connected to vessel, rotor working element, bump stops, and also receiving hopper for finished product. Through holes of separating plate are arranged in the form of truncated cones, smaller bases of which face towards vessel inside, besides ratio of through holes inlet and outlet diametre equals 1:1.5-1.6. Bump stops are arranged in the form of rectangular plates installed radially on upper cover of body, and receiving hopper is tightly joined by means of pipeline to container for finished product equipped with bag filter to develop directed gas dispersed flow from supply nozzle through working space of vessel into container for finished product. Ratio of vessel height and diametre makes 1:3-4.

EFFECT: increased efficiency of hard-to-grind materials grinding, making product of uniform granulometric composition, increased efficiency of operation, improved labour conditions due to reduction of workplace dustiness and reduced losses of ground material.

2 cl, 2 dwg

Description

The invention relates to devices for grinding materials and can be used in various industries, in particular in the food, fish, chemical, processing industries, agriculture, etc. for the processing of difficult to grind materials and products.

A device is known [US Pat. RF №2313394, publ. 2007.12.27] for the preparation of feed and the processing of grain waste, including a housing, a rotor, a cylindrical sieve shell, in which the rotor is made in the form of an impeller with two blades, rods are installed uniformly over the entire height of the working shell around the height of the working chamber, having the shape of a regular prisms, moreover, the housing, the rotor, the shell are combined in the upper module connected to the lower module, which is a housing with a through hole having the shape of a truncated cone, inside of which are longitudinal the basics, cutters. The known device is difficult to manufacture and operate and energy-intensive, as it includes two electric motors. In addition, the known device does not provide effective crushing of durable materials.

Known chopper centrifugal rotor-knife type [US Pat. RF №2270057, publ. 2006.02.20.], Intended for grinding plant materials and bulk materials, including a housing in which two disks with alternating ring protrusions are horizontally and coaxially mounted, in which there are through grooves in the radial direction, and the grinding chamber contains two steps. A disadvantage of the known device is the impossibility of grinding bulk materials of high hardness, as well as the complexity of the design and its manufacture, high metal consumption.

The closest technical solution to the claimed is a material shredder [US Pat. RF №2304023, publ. 2007.08.10], comprising a cylindrical body with an unloading window, covered by a deck with through holes, a vertical feed pipe connected to the body, a rotary working body provided with radial blades, and chippers placed on the inner cylindrical surface of the body. The chopper is equipped with a hopper for the finished product.

A disadvantage of the known device is the insufficiently high grinding efficiency, especially in the processing of difficult to grind materials, the possibility of clogging the deck holes with crushed material at particle sizes close to the dimensions of the deck holes, which makes it difficult to obtain a finished product of a uniform particle size distribution, as well as high dustiness of the workplace during operation and loss of ground material.

The objective of the invention is the creation of a grinder with advanced technological capabilities, providing the grinding of difficult to grind materials, obtaining a product of uniform particle size distribution, which is crucial in assessing the quality of many grinded materials, increasing productivity, improving working conditions by reducing dustiness of the workplace and reducing losses of crushed material .

The technical result of the claimed invention is to prevent clogging of the holes through which the crushed material is removed, to increase the grinding efficiency, including difficult to grind materials, to reduce the residence time of the crushed material in the workspace, to prevent the discharge of the crushed material into the environment.

The specified technical result is achieved by the fact that in the grinder, containing a cylindrical body with a lid and an unloading window, blocked by a deck in the form of a separating plate with through holes, a vertical feed pipe connected to the body, a rotary working body, chippers, as well as a receiving hopper for the finished product , in contrast to the known one, the through holes of the separating plate are made in the form of truncated cones facing with smaller bases into the housing, and the ratio of the diameters of the inlet and outlet with the through holes is 1: 1.5-1.6, while the chippers are made in the form of rectangular plates mounted radially on the top cover of the housing, and the receiving hopper for the finished product is hermetically connected by means of a pipeline to the container for the finished product equipped with a bag filter to create directed gas-dispersed flow from the supply pipe through the working space of the housing into the container for the finished product.

Optimum is the ratio of the height and diameter of the chopper body, equal to 1: 3-4.

The essence of the claimed technical solution is illustrated by the drawing, where in Fig.1 shows a General view of the device, Fig.2 is a segment of a separating plate with a hole.

The proposed device includes a vertical feed pipe 1, through which the crushed material is fed into the cylindrical body 2 mounted on the bed 3. The diameter of the cylindrical body 2 is three to four times its height. Inside the housing 2 in the working space is placed a rotary working body, including a shaft, which is driven by an AC electric motor 4 in rotation with a frequency of about 3000 rpm; with a knife 5 fixed to the shaft, which is a plate with bent ends, made of especially durable material, for example, wear-resistant steel (in particular, grades 12X13, 25X13H2, 12X18H9, etc.). On the lid 6 of the housing 2 on the inside there are four chippers 7 in the form of rectangular plates, also made of wear-resistant steel. The casing 2 is equipped with an unloading window located in its side wall, which is overlapped by a separating plate 8 made of wear-resistant steel with through holes in the form of truncated cones facing smaller bases into the casing, while the diameter of the outlet openings of the plate exceeds the diameter of the inlets.

To obtain crushed materials of varying degrees of dispersion, replaceable separating plates with an appropriate hole size are used. The insignificant thickness of the separating plate allows using the laser burning method to obtain holes of a given shape and size.

By means of an unloading window provided with a separating plate 8, the working space of the housing 2 is connected to the receiving hopper 9 and then through the unloading pipe 10 with the container 11 for the finished product, which is equipped with a bag filter 12 sealed to it.

The device operates as follows.

The crushed material, for example agar chips, is fed into the working space inside the cylindrical casing 2 through the vertical feed pipe 1. The agar chips, falling into the working space, are exposed to the knife 5 rotating at high speed, which leads to the grinding of the chips and the simultaneous formation of a swirling gas-powder stream ( gas dispersed) mixture. Agar particles, carried away by a swirling flow, hit the bumpers 7 with high speed, which leads to additional grinding of the particles.

Thus, grinding occurs due to the impact on the grinding material of a rotating knife 5, as well as the collision of particles with the walls of the chamber, their collisions with each other and with the plates of the radial chippers 7. The grinding effect of the chippers with an insignificant height of the casing in comparison with its diameter is most effective that in combination with the impact of impact-resistant made of wear-resistant material of the knife 5 and the separating plate 8 provides effective grinding of difficult to grind materials.

Moreover, the specified ratio of height and diameter of the housing 2 gives an additional advantage in the form of a general reduction in size and metal consumption of the grinder.

Rotary knife 5 plays the role of a swirl of air, which creates a swirling gas dispersed stream. Particles of material, such as agar, formed during grinding, moving in this swirling flow, are discarded to the walls of the casing 2 by the action of centrifugal force and then removed from it through an outlet in the wall, closed by a separating plate 8.

The difference in the size of the inlet and outlet of the through holes made in the form of truncated cones in the separating plate 8 prevents particles from clogging the holes, especially when producing fine powders, in particular with particle sizes less than 1 mm, while an optimal result is achieved with a diameter ratio the entrance and exit of the through holes equal to 1: 1.5-1.6 (figure 2). When entering a hole with a smaller diameter at the entrance, the particles freely move further towards the exit with a larger diameter, which effectively prevents clogging of the holes of the separating plate.

Particles of crushed material, for example agar, which have reached an appropriate size, pass through the openings in the separating plate 8 through the discharge window and enter the receiving hopper 9, from where they are collected in the container 11 for the finished product by means of the discharge pipe 10. Bag filter 12 allows you to create a directed gas-dispersed flow from the vertical feed pipe 1 through the working space into the container 11 for the finished product. The gas-dispersed flow is directed in the supply pipe 1 from top to bottom, in the grinder working space from the center to the periphery, in the receiving hopper 9 and discharge pipe 10 from the inlet to the outlet, due to which the bag filter 12 is inflated during operation of the device and takes the form shown in figure 1. After stopping, it “falls off”, while the finest pulverulent fraction of the crushed substance, such as agar powder, is retained by a bag filter.

The formation of a directed gas-dispersed flow, as well as the capture of a pulverized fraction of a crushed substance by a bag filter, increases the grinder's productivity by reducing the residence time of crushed particles in the workspace and avoids dustiness in the workplace, which improves working conditions.

Claims (2)

1. The chopper, comprising a cylindrical body with a lid and an unloading window, blocked by a deck in the form of a separating plate with through holes, a vertical feed pipe connected to the housing, a rotary working body, chippers, and also a receiving hopper for the finished product, characterized in that through the holes of the separating plate are made in the form of truncated cones facing with smaller bases into the housing, and the ratio of the diameters of the inlet and outlet of the through holes is 1: 1.5-1.6, while the bumpers are made us in the form of rectangular plates arranged radially on top of the housing, and the receiving hopper is sealingly connected via a pipe to a container for the finished product, equipped with a bag filter to create a directional flow of the feed gas-dispersion tube through the working space of the housing into the container for the finished product. 2. The chopper according to claim 1, characterized in that the ratio of the height and diameter of the housing is 1: 3-4.

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