CN111774149B

CN111774149B - Symmetrical eccentric main shaft assembly hammer crusher

Info

Publication number: CN111774149B
Application number: CN202010627786.5A
Authority: CN
Inventors: 张春洪; 高志伟; 潘嘉亮
Original assignee: Liyang Hongyue Machinery Manufacture Co ltd
Current assignee: Liyang Hongyue Machinery Manufacture Co ltd
Priority date: 2020-07-02
Filing date: 2020-07-02
Publication date: 2022-02-08
Anticipated expiration: 2040-07-02
Also published as: CN111774149A

Abstract

The invention relates to a hammer mill with a symmetrical eccentric main shaft assembly, which comprises a milling bin, wherein a milling main shaft is arranged in the milling bin, the milling main shaft is sequentially divided into a left connecting section, a left eccentric section, a middle shaft shoulder, a right eccentric section and a right connecting section, and the left connecting section and the right connecting section are symmetrically arranged and are respectively inserted into two bearings on a shell of the milling bin; the central axes of the left connecting section, the right connecting section and the middle shaft shoulder are overlapped, the central axes of the left connecting section, the left eccentric section, the middle shaft shoulder, the right eccentric section and the right connecting section are parallel and positioned in the same plane, and the lengths and the diameters of the left eccentric section and the right eccentric section are equal; the eccentricity of the left eccentric section and the right eccentric section is equal, and the directions are opposite; the hammer piece is installed on left eccentric section and right eccentric section, the hammer piece of left eccentric section is central symmetry setting with the hammer piece of right eccentric section. The invention can be used for coarse crushing and micro crushing, thereby realizing two purposes of one machine.

Description

Symmetrical eccentric main shaft assembly hammer crusher

Technical Field

The invention relates to a hammer crusher with a symmetrical eccentric main shaft assembly, and belongs to the technical field of hammer crushers.

Background

The crushing of the feed raw materials is an important link in feed processing, the total surface area of raw material particles per unit mass can be increased through crushing, the solubility of feed nutrients in animal digestive juice is increased, and the digestibility of animals is improved. The hammer mill is a widely used feed mill, and the structure of the hammer mill generally comprises a feeding mechanism, a milling bin (a rotating shaft, a hammer, a sieve sheet and a toothed plate) and a discharging mechanism (a fan, a material collecting cylinder and a dust collecting cloth bag).

In a common hammer mill, a main shaft of the mill is a rotating shaft, a bearing, a hammer frame plate, a pin shaft, a hammer and other parts are arranged on the rotating shaft by taking the rotating shaft as a center to form a mill rotor assembly with balanced rotation, an arc-shaped (water drop-shaped) screen is further surrounded outside the rotor assembly, when a mill motor is started to enable the mill main shaft to rotate, the whole rotor assembly is driven to rotate, at the moment, gaps between end points of the hammer and corresponding points of the screen are unchanged, parameters of annular air flow generated due to high-speed rotation of the rotor assembly are also kept unchanged (air speed, air pressure, air quantity and the like), and accordingly the screening capacity of crushed materials rotating along with the annular air flow is also unchanged.

According to the crushing theory, the crushing yield can be improved by changing the crushing circulation parameters within each circle of rotation of the rotor assembly, the crushed material has stronger sieving capacity when the hammer sieve clearance is reduced, and the crushed material has weaker sieving capacity when the hammer sieve clearance is increased. In addition, the screen of the hammer mill is usually made of a thin steel plate or a punched hole made of an iron sheet, and according to the production process and the standard of the screen (for example, the screen aperture for producing fish, shrimp and aquatic feed is usually smaller than 1mm, and the thickness is usually smaller than 1 mm), when the screen is micro-ground, especially when the screen aperture is smaller than 1mm, the aperture ratio of the screen is lower, often smaller than 20%, at this time, the screen resistance is increased sharply, and the screening efficiency of the ground material is greatly reduced.

In order to improve the sieving efficiency and increase the micro-crushing yield, the gap between the hammer sieve and the sieve needs to be reduced, but after the gap between the hammer sieve and the sieve is reduced, the sieve blocking fault can often occur, and the crusher can not work due to the sieve blocking fault in both coarse crushing and micro-crushing. Although the blockage is easy, the gap between the hammer and the sieve must be reduced to increase the sieving efficiency when the existing hammer crusher is used for micro crushing, the sieve is difficult to block due to larger aperture of the sieve net, large aperture ratio and small resistance of the sieve net during coarse crushing. Based on the above reasons, the common hammer mill is usually used during coarse grinding, a screen with a larger aperture is selected, special micro-mills with different designs are used during micro-grinding, screens with an aperture smaller than 2mm are adopted, and the gap between the hammer and the screen is simultaneously reduced, or an airflow classification mechanism is used for replacing a micro-aperture screen with a very large resistance to obtain a large micro-grinding yield, so that the cost is high, the occupied space is large, the operation is troublesome, and the working efficiency is reduced.

Disclosure of Invention

The invention aims to solve the technical problems that: provided is a hammer mill which can be used for both coarse grinding and fine grinding and which can be used as a single machine.

In order to solve the technical problems, the technical scheme provided by the invention is as follows: a symmetrical eccentric main shaft assembly hammer piece crusher comprises a crushing bin, wherein a crushing main shaft, a screen and a plurality of hammer pieces arranged on the crushing main shaft are arranged in the crushing bin, and two ends of the crushing main shaft are arranged on a shell of the crushing bin through two bearings; the crushing main shaft is sequentially divided into a left connecting section, a left eccentric section, a middle shaft shoulder, a right eccentric section and a right connecting section, and the left connecting section and the right connecting section are arranged in a bilateral symmetry mode and are respectively supported in two bearings on the crushing bin shell; the central axes of the left connecting section, the middle shaft shoulder and the right connecting section are overlapped, the central axes of the left connecting section, the right connecting section, the left eccentric section, the right eccentric section and the middle shaft shoulder are parallel and positioned in the same plane, and the lengths and the diameters of the left eccentric section and the right eccentric section are equal; the eccentricity of the left eccentric section and the right eccentric section is equal, and the directions are opposite; the hammer piece is arranged on the left eccentric section and the right eccentric section.

The center of the rotor assembly of the invention adopts a symmetrical eccentric main shaft (crushing main shaft), and the gap of the hammer screen can be periodically changed within the range of each rotation (360 degrees) of the rotor assembly, so that the crushing annular airflow can be actively destroyed by the rotation of the rotor assembly, thereby increasing the speed difference between the hammer sheet and the crushed feed, and further increasing the hitting force of the hammer sheet on the crushed material.

Meanwhile, when the invention is used, the crushing main shaft can make the hammer screen clearance undergo dynamic change from small to large and then from large to small within one rotation (360 degrees). Compared with the common coarse powder hammer crusher, the hammer sieve clearance is smaller than that of the common coarse powder hammer crusher in most of time due to the periodic dynamic change of the hammer sieve clearance, so that the sieving efficiency is improved; compared with a special micro-crushing hammer piece crusher, due to the fact that crushing annular airflow is actively destroyed, parameters of the annular airflow can change in the rotating process of a crushing main shaft, the speed difference between a hammer piece and crushed feed is increased, the hammer sieve gap changes dynamically, and therefore the pressure applied to a screen changes all the time, vibration of the screen is facilitated, screen blocking faults are greatly reduced, micro-crushing yield can be greatly improved, and obvious economic benefits can be obtained. Therefore, the invention can be used for coarse crushing and micro crushing, realizes dual purposes by replacing screens with different apertures, does not need to replace a crusher or change the positioning size of the hammer on the rotor assembly, and improves the working efficiency.

Drawings

The invention will be further explained with reference to the drawings.

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

Fig. 2 is a sectional view a-a in fig. 1.

Fig. 3 is an enlarged view of a portion B in fig. 2.

Reference numerals: the crushing device comprises a screen 1, a discharge port 2, a crushing bin 3, a crushing main shaft 4, a left connecting section 4-1, a left eccentric section 4-2, a middle shaft shoulder 4-3, a right eccentric section 4-4, a right connecting section 4-5, a bearing seat 5, a feed port 6, a hammer sheet 7, a pin shaft 8, a hammer frame plate 9, a coupler 10, a motor 11 and a bearing 12.

Detailed Description

Examples

The symmetrical eccentric main shaft assembly hammer piece crusher of the embodiment, as shown in fig. 1-3, comprises a crushing bin 3, wherein the crushing bin is internally provided with a crushing main shaft 4, a screen 1 and a plurality of hammer pieces 7 arranged on the crushing main shaft 4, the crushing bin 3 is fixed on a base, the upper part of the crushing bin is a feed inlet 6, the lower part of the crushing bin is a discharge outlet 2, the left side and the right side of the crushing bin 3 are fixedly connected with a bearing seat 5 respectively, and two ends of the crushing main shaft 4 are arranged on a shell of the crushing bin 3 through two bearings 12.

The crushing main shaft 4 is an integral part and is sequentially divided into a left connecting section 4-1, a left eccentric section 4-2, a middle shaft shoulder 4-3, a right eccentric section 4-4 and a right connecting section 4-5, the left connecting section 4-1 and the right connecting section 4-5 are arranged in bilateral symmetry and also serve as bearing stops, and the left connecting section 4-1 and the right connecting section 4-5 are respectively supported on two bearings 12 on a shell of the crushing bin 3, so that the axial fixation is kept, and the free rotation is realized.

The central axes of the left connecting section 4-1, the middle shaft shoulder 4-3 and the right connecting section 4-5 are overlapped, the central axes of the left connecting section 4-1, the middle shaft shoulder 4-3, the right connecting section 4-5, the left eccentric section 4-2 and the right eccentric section 4-4 are parallel and positioned in the same plane, and the lengths and the diameters of the left eccentric section 4-2 and the right eccentric section 4-4 are equal; the eccentricity of the left eccentric section 4-2 and the right eccentric section 4-4 is equal, and the directions are opposite. The hammer 7 is arranged on the left eccentric section 4-2 and the right eccentric section 4-4. Preferably, the hammer sheet of the left eccentric section 4-2 and the hammer sheet of the right eccentric section 4-4 are arranged in a central symmetry manner.

In implementation, the hammer frame plates 9 with the same size, the same number and the same interval are respectively and fixedly connected to the left eccentric section 4-2 and the right eccentric section 4-4, the pin shafts 8 with the same size and the same number are respectively and fixedly connected to hammer pin holes uniformly distributed on the hammer frame plates 9, the hammer sheets 7 with the same size and the same number are respectively sleeved on the pin shafts 8, the hammer sheets 7 can freely swing around the pin shafts 8, and the installation mode of the hammer sheets 7 is the prior art and is not described again. The rotational dynamic balance precision of the rotor of the crusher can be ensured by the conventional dynamic balance process correction of the rotor of the crusher, namely, the symmetric eccentric rotor assembly of the crusher consisting of the crushing main shaft 4, the hammer frame plate 9, the hammer pin shaft 8, the hammer sheet 7 and other related parts achieves the rotational dynamic balance precision, when the symmetric eccentric rotor assembly rotates for a circle (360 degrees), the inertial centrifugal force and moment generated by the left eccentric section 4-2, the hammer frame plate 9 connected with the left eccentric section, the hammer pin shaft 8 and the hammer sheet 7 are equal in magnitude and opposite in direction to the inertial centrifugal force and moment generated by the right eccentric section 4-4, the hammer frame plate 9 connected with the right eccentric section, the hammer pin shaft 8 and the hammer sheet 7, and the rotation center of the symmetric eccentric rotor is superposed with the center line of the symmetric main shaft and is in a dynamic balance state.

As shown in fig. 2 and 3, the screen mesh 1 is fixedly connected to the inside of the pulverizing bin 3, the symmetrical eccentric spindle rotor assembly is arranged inside the screen mesh 1, the minimum gap between the screen mesh 1 and the hammer 7 is δ, the eccentricity of the left eccentric section 4-2 and the right eccentric section 4-4 is e, when the symmetrical eccentric rotor assembly rotates around the central axis of the left connecting section and the right connecting section for one circle, the hammer-screen gap changes from δ to δ + e, and then returns to δ from δ + e, that is, when the hammer-screen gap at the tail end of the hammer on the left eccentric section is δ, the hammer-screen gap at the tail end of the hammer on the right eccentric section is δ + e, and vice versa.

As shown in fig. 1, the right end of the crushing main shaft 4 is fixedly connected with a motor 11 through a coupling 10, the motor 11 is fixed on a foundation, the motor 11 is started to drive the symmetrical eccentric rotor assembly to rotate stably, and the hammer crusher works normally.

Compared with the prior art, the common rotor assembly is replaced by the symmetrical eccentric main shaft rotor assembly, and other components such as the crushing bin, the screen, the coupling, the motor and the like are kept unchanged. Through the improvement, the hammer sieve gap can undergo dynamic change from small to large and then from large to small within one rotation (360 degrees) of the crushing main shaft, and compared with an ordinary coarse powder hammer crusher, the hammer sieve gap dynamic change (the hammer sieve gap of the ordinary coarse powder hammer crusher is approximately equivalent to the largest hammer sieve gap in the embodiment, so the hammer sieve gap in the use process of the embodiment is equivalent to be reduced), so the sieving efficiency is improved; compared with a special micro-crushing hammer piece crusher, the speed difference between the hammer piece and the crushed feed is increased due to the active damage of the crushing annular airflow, and the hammer sieve clearance is dynamically changed, so that the sieve blocking fault is greatly reduced, and the micro-crushing yield is greatly improved. The embodiment can be used for coarse crushing and micro crushing, can realize dual purposes only by replacing screens with different apertures, does not need to replace a crusher or change the positioning size of the hammer on the rotor assembly, and therefore improves the production efficiency.

As shown in fig. 1, the central axis of the middle shaft shoulder 4-3 coincides with the central axes of the left connecting section 4-1 and the right connecting section 4-5, that is, the left eccentric section 4-2 and the right eccentric section 4-4 of the crushing main shaft 4 are separated by the middle shaft shoulder 4-3, and the middle shaft shoulder 4-3 not only can make the crushing main shaft 4 easier to manufacture and process, facilitates the positioning of the crushing main shaft 4 during the installation, but also reduces the stress concentration at the joint of the left eccentric section 4-2 and the right eccentric section 4-4.

The present invention is not limited to the specific technical solutions described in the above embodiments, and other embodiments may be made in the present invention in addition to the above embodiments. It will be understood by those skilled in the art that various changes, substitutions of equivalents, and alterations can be made without departing from the spirit and scope of the invention.

Claims

1. A symmetrical eccentric main shaft assembly hammer piece crusher comprises a crushing bin, wherein a crushing main shaft, a screen and a plurality of hammer pieces arranged on the crushing main shaft are arranged in the crushing bin, and two ends of the crushing main shaft are arranged on a shell of the crushing bin through two bearings; the method is characterized in that: the crushing main shaft is sequentially divided into a left connecting section, a left eccentric section, a middle shaft shoulder, a right eccentric section and a right connecting section, and the left connecting section and the right connecting section are symmetrically arranged and are respectively supported on two bearings on the crushing bin shell; the central axes of the left connecting section, the middle shaft shoulder and the right connecting section are overlapped, the central axes of the left connecting section, the left eccentric section, the middle shaft shoulder, the right eccentric section and the right connecting section are parallel and positioned in the same plane, and the lengths and the diameters of the left eccentric section and the right eccentric section are equal; the eccentricity of the left eccentric section and the right eccentric section is equal, and the directions are opposite; the hammer piece is arranged on the left eccentric section and the right eccentric section.

2. The symmetrical eccentric spindle assembly hammer mill of claim 1, wherein: the hammer sheet of the left eccentric section and the hammer sheet of the right eccentric section are arranged in a centrosymmetric manner.

3. The symmetrical eccentric spindle assembly hammer mill of claim 2, wherein: the distance between the adjacent hammer sheets of the left eccentric section is equal, and similarly, the distance between the adjacent hammer sheets of the right eccentric section is also equal.