Jet mill

Abstract

The utility model discloses a jet mill in the technical field of particle crushing, and aims to solve the problem that a Laval nozzle of a jet mill in the prior art cannot detect whether the Laval nozzle can work normally or not. The device comprises a support and a crushing cylinder arranged on the support, a plurality of Laval nozzles communicated with external high-pressure gas are arranged in an inner cavity of the crushing cylinder, a perspective window is arranged on the crushing cylinder and close to the Laval nozzles, a laser Doppler flow velocity measuring instrument is arranged at the perspective window, and a laser Doppler flow velocity measuring instrument is arranged on the laser Doppler flow velocity measuring instrument. Laser of the laser Doppler flow velocity measuring instrument can penetrate through the perspective window to point to the front end position of an air jet port of the Laval nozzle; the monitoring device is used for monitoring the working state of the Laval nozzle in the operation of the jet mill, can remind the Laval nozzle to be replaced in time when the Laval nozzle is abnormal, is favorable for ensuring the efficient and normal operation of the jet mill, and can save the use cost of the nozzle.

Description

Technical Field

[0001] The utility model relates to an air flow pulverizer, belonging to the technical field of particle crushing and pulverizing. Background Art

[0002] Air flow mill is a device that uses high-pressure air flow to blow out fine particles and cause them to collide, thereby achieving particle crushing. In order to achieve high-intensity air flow, a Laval nozzle is often used to spray the air flow at a supersonic speed. However, during the use of this nozzle, the powdered particles in the air will constantly rub against the nozzle. Even if a little wear is caused at the nozzle position, it will have a significant impact on the nozzle's airflow. Therefore, the nozzle needs to be replaced after a period of time to ensure the normal operation of the equipment.

[0003] However, since there are a large number of nozzles in the equipment and some of the nozzles may not be worn, if they are replaced uniformly and regularly, the use cost of the equipment will increase. If they are not replaced uniformly, it will be difficult to determine whether the nozzles in the grinder are working properly. Once inefficiency occurs, it is difficult to determine which nozzle has a problem. Therefore, a nozzle flow rate monitoring device is urgently needed to determine whether the nozzle is working properly, so as to manually replace only the damaged nozzles, thereby saving the application cost of the equipment. Summary of the invention

[0004] The purpose of the utility model is to overcome the deficiencies in the prior art and to provide an air flow pulverizer for monitoring the working status of the Laval nozzle during the operation of the air flow pulverizer. When an abnormality occurs in the Laval nozzle, a prompt replacement can be given in time, which is beneficial to ensuring the efficient and normal operation of the air flow pulverizer and can save the use cost of the nozzle.

[0005] In order to achieve the above purpose, the utility model is implemented by adopting the following technical solutions:

[0006] The utility model provides an air flow pulverizer, comprising a bracket and a pulverizing tube arranged on the bracket, the inner cavity of the pulverizing tube is provided with a plurality of Laval nozzles connected to external high-pressure gas, a perspective window is provided on the pulverizing tube and close to the Laval nozzle, a laser Doppler flow velocity meter is provided at the position of the perspective window, and the laser of the laser Doppler flow velocity meter can point to the front end position of the Laval nozzle jet outlet through the perspective window.

[0007] Specifically, the perspective window is annularly arranged on the circumference of the pulverizing cylinder or the perspective window is provided with a plurality of windows corresponding to each of the Laval nozzles. The laser Doppler flow meter is movably installed on the outer circumference of the pulverizing cylinder. The laser Doppler flow meter can be moved so that the laser it emits points to the air outlet position at the front end of each Laval nozzle and the distance between the pointing position of the laser and the corresponding Laval nozzle is equal.

[0008] Specifically, it includes an annular track fixedly mounted on the outer wall of the pulverizing cylinder and a movable part slidably mounted on the annular track. The movable part can slide along the annular path provided by the annular track, and the laser Doppler flow meter is fixedly arranged on the movable part.

[0009] Specifically, the annular track includes at least two splicing parts that can be spliced ​​together to form an annular track, the splicing parts include an arc-shaped positioning plate and a support rod arranged on the arc-shaped positioning plate and extending toward the outer side of the arc-shaped surface, the support rod is positioned and installed with an arc track, the splicing parts are spliced ​​together through the arc-shaped positioning plates to form an annular body for being embedded in the surface of the grinding barrel, the arc track forms a circular track after splicing, and the movable part can slide on the circular track.

[0010] Specifically, the support rod and the circular arc track are symmetrically distributed on the upper and lower sides of the arc-shaped positioning plate. The arc-shaped positioning plate is provided with an opening for leaking a perspective window on the crushing cylinder. The movable part includes a plate body and circular arc-shaped holding plates arranged on the upper and lower sides of the plate body. The two circular arc-shaped holding plates are respectively embedded and slidably arranged on the circular arc tracks on the upper and lower sides. The laser Doppler flow meter is installed on the plate body.

[0011] Specifically, the plate body includes a first plate body and a second plate body, the arc-shaped holding plates located on the upper and lower sides are respectively arranged on the first plate body and the second plate body, and the first plate body and the second plate body are connected by bolts.

[0012] Specifically, there is a gap between the first plate body and the second plate body.

[0013] Specifically, a first positioning hole is provided on the circular arc track, and a second positioning hole is provided on the circular arc-shaped holding plate.

[0014] Specifically, the support rod has an L-shaped structure.

[0015] Compared with the prior art, the utility model has the following beneficial effects:

[0016] The utility model arranges a perspective window on the pulverizing cylinder, and arranges a laser Doppler flow velocity measuring instrument at the perspective window position to detect the airflow velocity at the Laval nozzle position, and can warn the nozzle at the abnormal flow velocity position, so as to facilitate the maintenance of the equipment and reduce the frequency of replacing the nozzle, thereby realizing the cost saving of the long-term application of the airflow pulverizer. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the airflow pulverizer provided by the embodiment of the utility model;

[0018] Figure 2 It is a schematic diagram of the overall structure of the pulverizing cylinder provided in the embodiment of the utility model;

[0019] Figure 3 It is a front view of the air flow pulverizer provided by the embodiment of the utility model;

[0020] Figure 4 This utility model Figure 3 A cross-sectional view of the airflow pulverizer provided in the embodiment along the AA direction;

[0021] Figure 5 It is a structural schematic diagram of the splicing piece provided by an embodiment of the utility model;

[0022] Figure 6 It is a schematic diagram of the overall structure of the movable parts provided by the embodiment of the utility model;

[0023] Figure 7 It is a side view of the movable part provided by the embodiment of the utility model;

[0024] Figure numerals: 1. bracket; 2. crushing cylinder; 3. perspective window; 4. laser Doppler flow meter; 5. circular track; 501. arc positioning plate; 502. support rod; 503. opening; 504. arc track; 505. first positioning hole; 6. movable part; 601. first plate body; 602. second plate body; 603. mounting plate; 604. arc holding plate; 605. second positioning hole; 606. bolt. DETAILED DESCRIPTION

[0025] The utility model is further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the utility model, and cannot be used to limit the protection scope of the utility model.

[0026] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0027] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances. Example

[0028] The utility model provides an air flow pulverizer, which can monitor the working state of the Laval nozzle during operation and promptly remind replacement when the Laval nozzle is abnormal, which is conducive to ensuring the efficient and normal operation of the air flow pulverizer and can save the use cost of the nozzle. In order to realize the structural function of the device, the device is provided here including a bracket 1 and a pulverizing tube 2 arranged on the bracket 1, and the inner cavity of the pulverizing tube 2 is provided with a plurality of Laval nozzles connected to the external high-pressure gas, such as Figure 2As shown, a perspective window 3 is provided on the pulverizing cylinder 2 and near the Laval nozzle, and a laser Doppler flow meter 4 is provided at the position of the perspective window 3. The laser of the laser Doppler flow meter 4 can point to the front end of the Laval nozzle jet through the perspective window 3. When the device is working, the monochromatic laser emitted by the laser Doppler flow meter 4 shines on the injection area of ​​the particles at the front end of the nozzle through the perspective window 3. The light scattered by the particles in the fluid is then received by the optical receiver and converted into an electrical signal. The obtained electrical signal is amplified, filtered, and spectrum analyzed, and finally the relevant information of the fluid velocity is extracted. It should be noted that when the device is in use, the outlet end of the Laval nozzle is continuously diffused along the outlet direction, and the flow velocity is continuously reduced. The laser pointing position of the laser Doppler flow meter 4 should point to the position where the airflow diffuses to avoid the situation where the airflow velocity is too large and the device cannot meet the measurement requirements.

[0029] The air flow pulverizer provided by the embodiment of the utility model is not suitable for setting a laser Doppler flow meter 4 at the position of each nozzle in consideration of the high equipment cost of the laser Doppler flow meter 4. However, in order to realize the flow velocity monitoring of all nozzles, at least the laser Doppler flow meter 4 needs to be set to be able to point the light source at the corresponding nozzle positions of multiple nozzles to realize the monitoring of each nozzle. As a preferred embodiment, a perspective window 3 is set in an annular shape on the peripheral side of the pulverizing cylinder 2 or a plurality of perspective windows 3 are set respectively corresponding to each Laval nozzle. At this time, the laser Doppler flow meter 4 is set to the corresponding nozzle position of each nozzle. The velocity measuring instrument 4 is movably installed on the outer peripheral side of the grinding cylinder 2. The laser Doppler velocity measuring instrument 4 can move so that the laser it emits is directed to the air outlet position at the front end of each Laval nozzle respectively, and the distance between the pointing position of the laser and the corresponding Laval nozzle is equal. By controlling the movement of the laser Doppler velocity measuring instrument 4, the distance between the pointing position of the laser and the position of the Laval nozzle is equal. If a large change in the flow velocity fluctuation range occurs at the detection position, or the change amplitude exceeds the set threshold, it can be determined that the flow velocity of the nozzle here is abnormal, and the nozzle at this position can be replaced according to the actual situation.

[0030] An air flow pulverizer provided by an embodiment of the utility model is designed to avoid a difference in the distance between the laser Doppler flowmeter 4 and the Laval nozzle after the laser Doppler flowmeter 4 moves, thereby causing a large change in the flow rate difference detected by the laser Doppler flowmeter. A corresponding movable mechanism is provided here to include an annular track 5 fixedly installed on the outer wall of the pulverizing cylinder 2 and a movable part 6 slidably installed on the annular track 5, wherein the movable part 6 can slide and move along the annular path provided by the annular track 5, and the laser Doppler flowmeter 4 is fixedly arranged on the movable part 6. By controlling the movable part 6 to move in a circle on the annular track 5, it is ensured that the distance between the laser Doppler flowmeter 4 and the pulverizing cylinder 2 is maintained at a specific distance, thereby avoiding a change in the pointing position of the laser of the laser Doppler flowmeter 4 after the position change, thereby causing inaccurate gas flow rate detection.

[0031] The air flow pulverizer provided by the embodiment of the utility model specifically provides a ring track 5 structure. Since the ring track 5 is a ring structure and needs to be relatively fixedly arranged on the outer peripheral side of the pulverizing tube 2, in order to facilitate installation, the ring track 5 is provided here to include at least two splicing pieces that can be spliced ​​to form the ring track 5. Specifically, the splicing pieces provided here include an arc-shaped positioning plate 501 and a support rod 502 arranged on the arc-shaped positioning plate 501 and extending to the outer side of the arc surface, such as Figure 5 As shown, a circular arc track 504 is positioned and installed on the support rod 502, and the splicing parts are spliced ​​together through the arc positioning plate 501 to form a ring-shaped body for being embedded in the surface of the grinding cylinder 2. The circular arc track 504 forms a circular ring track after splicing. In order to ensure the stability of the splicing of the circular ring track, a corresponding connecting rod joint can be set at the splicing position. At this time, the movable part 6 can be set to be able to slide on the circular ring track.

[0032] The air flow pulverizer provided in the embodiment of the utility model specifically provides a joint structure of a movable part 6 and an annular track 5 so that it can slide on the arc track 504. Specifically, the support rod 502 and the arc track 504 are symmetrically distributed on the upper and lower sides of the arc positioning plate 501. Figure 5 As shown, an opening 503 is provided on the arc-shaped positioning plate 501 for exposing the perspective window 3 on the grinding cylinder 2, and a movable part 6 is provided, including a plate body and arc-shaped holding plates 604 arranged on the upper and lower sides of the plate body. The two arc-shaped holding plates 604 are respectively fitted and slidably arranged on the arc tracks 504 on the upper and lower sides. The arc trend path of the arc-shaped holding plates 604 coincides with the arc path of the arc track 504. The cross-section of the arc-shaped holding plates 604 is semicircular so that it can be hooked on the arc track 504. Under the comprehensive effect, it can slide along the arc track 504. At this time, the laser Doppler flow meter 4 can be installed on the plate body. Its installation can refer to Figure 6As shown, an opening is provided on the plate body, and a mounting plate 603 is provided on the opening. The mounting plate 603 is used to install the laser Doppler flow meter 4.

[0033] An air flow pulverizer provided by an embodiment of the utility model, in order to facilitate the installation of the movable part 6 on the circular track 5, a plate body is provided here including a first plate body 601 and a second plate body 602, specifically, the arc-shaped holding plates 604 located on the upper and lower sides are respectively arranged on the first plate body 601 and the second plate body 602, and the first plate body 601 and the second plate body 602 are connected by bolts 606. This arrangement method can first hook the arc-shaped holding plates 604 of the first plate body 601 and the second plate body 602 on the arc track 504, and then splice and install the first plate body 601 and the second plate body 602. A gap can be set between the first plate body 601 and the second plate body 602, and by ensuring that there is enough gap between the two, so that when adjusting the bolts 606, the two plates are locked with a sufficient distance to prevent their loose fit from causing unstable position.

[0034] An air flow pulverizer provided by an embodiment of the utility model is provided with a first positioning hole 505 on the circular arc track 504, and a second positioning hole 605 on the circular arc holding plate 604, in order to facilitate fixing the movable part 6 at a relatively stable position on the circular arc track 504 so that the laser Doppler flow meter 4 installed thereon can accurately point to the detection position. The first positioning hole 505 and the second positioning hole 605 can be aligned by inserting a positioning pin, and the position of the movable part 6 corresponding to the nozzle can be fixed by presetting the position of the first positioning hole 505.

[0035] In order to prevent the arc-shaped holding plate 604 from colliding with the support rod 502 during the movement of the air flow pulverizer provided in the embodiment of the utility model, the support rod 502 can be specifically configured to have an L-shaped structure, such as Figure 5 As shown, the diameter of the support rod 502 can also be set to be smaller than the diameter of the arc track 504, so as to increase the coverage range of the arc-shaped holding plate 604 on the arc track 504.

[0036] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A jet mill, characterized in that: The invention comprises a support (1) and a pulverizing tube (2) arranged on the support (1); the inner cavity of the pulverizing tube (2) is provided with a plurality of Laval nozzles communicating with external high-pressure gas; a perspective window (3) is arranged on the pulverizing tube (2) and close to the Laval nozzle; a laser Doppler flow meter (4) is arranged at the position of the perspective window (3); and the laser of the laser Doppler flow meter (4) can pass through the perspective window (3) and point to the front end position of the Laval nozzle jet outlet.

2. A jet mill according to claim 1, characterized in that: The perspective window (3) is annularly arranged on the circumference of the pulverizing cylinder (2) or the perspective window (3) is provided with a plurality of corresponding to each of the Laval nozzles. The laser Doppler flow velocity measuring instrument (4) is movably mounted on the outer circumference of the pulverizing cylinder (2). The laser Doppler flow velocity measuring instrument (4) can be movably moved so that the laser light emitted by it is respectively directed to the air outlet position at the front end of each Laval nozzle, and the distance between the laser pointing position and the corresponding Laval nozzle is equal.

3. A jet mill according to claim 2, characterized in that: It comprises an annular track (5) fixedly mounted on the outer wall surface of a pulverizing cylinder (2) and a movable part (6) slidably mounted on the annular track (5), the movable part (6) being able to slide along an annular path provided by the annular track (5), and the laser Doppler flow meter (4) being fixedly arranged on the movable part (6).

4. A jet mill according to claim 3, characterized in that: The annular track (5) comprises at least two splicing pieces that can be spliced ​​together to form the annular track (5), the splicing pieces comprising an arc-shaped positioning plate (501) and a support rod (502) arranged on the arc-shaped positioning plate (501) and extending toward the outer side of the arc-shaped surface, the support rod (502) being positioned and mounted with an arc track (504), the splicing pieces being spliced ​​together via the arc-shaped positioning plate (501) to form an annular body for embedding in the surface of the grinding cylinder (2), the arc track (504) forming an annular track after splicing, and the movable part (6) being able to slide on the annular track.

5. A jet mill according to claim 4, characterized in that: The support rods (502) and the circular arc tracks (504) are symmetrically distributed on the upper and lower sides of the arc-shaped positioning plate (501); the arc-shaped positioning plate (501) is provided with an opening (503) for leaking out the perspective window (3) on the pulverizing cylinder (2); the movable member (6) comprises a plate body and circular arc-shaped holding plates (604) arranged on the upper and lower sides of the plate body; the two circular arc-shaped holding plates (604) are respectively slidably arranged on the circular arc tracks (504) on the upper and lower sides; and the laser Doppler flow meter (4) is mounted on the plate body.

6. A jet mill according to claim 5, characterized in that: The plate body comprises a first plate body (601) and a second plate body (602), the arc-shaped holding plates (604) located at the upper and lower sides are respectively arranged on the first plate body (601) and the second plate body (602), and the first plate body (601) and the second plate body (602) are connected by bolts (606).

7. A jet mill according to claim 6, characterized in that: There is a gap between the first plate body (601) and the second plate body (602).

8. The air flow pulverizer according to claim 5, characterized in that: The arc track (504) is provided with a first positioning hole (505), and the arc-shaped holding plate (604) is provided with a second positioning hole (605).

9. The air flow pulverizer according to claim 5, characterized in that: The support rod (502) has an L-shaped structure.

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