TWI858031B - (無) - Google Patents

Abstract

The accumulation of powder of the solid raw material on the inner surface of the introduction part is suppressed. The pulverizing unit (11) includes: a pulverizing part (26) for pulverizing cocoa nibs (45) introduced into the inlet part (33) of the conical mortar (27) by the conical mortar (27); and an introduction part (25) having an opening part (25a) at the lower end with a diameter smaller than the inner diameter of the outer mortar (30) of the inlet part (33), and for introducing the cocoa nibs (45) from the opening part (25a) into the inlet part (33) of the conical mortar (27).

Description

Crusher

The present invention relates to a pulverizer for pulverizing solid raw materials such as cocoa beans.

As such a pulverizer, for example, an electric mill disclosed in Patent Document 1 is known. This electric mill includes: an input portion including an opening into which a pulverized object is input and sent to a lower stage; a coarse grinding portion for coarsely grinding the pulverized object from the introduction adjustment portion; a fine grinding portion for further finely grinding the pulverized object pulverized by the coarse grinding portion; and an adjustment portion for adjusting the amount of the pulverized object introduced into the fine grinding portion.

Furthermore, in Patent Document 1, the temperature of the introduction zone is configured to be lower than the temperature of the oil content contained in the pulverized material, and the temperature of the discharge zone is configured to be higher than the temperature of the oil content contained in the pulverized material, thereby preventing the cocoa bean powders from sticking to each other.

[Patent Document 1] Japanese Patent Publication No. 2018-69136.

However, the above-mentioned conventional grinders include the following problems. FIG. 10 is a longitudinal sectional view showing the structure of the main parts of the conventional grinder. The grinder 101 shown in FIG. 10 includes a conical mortar 111 including an inner mortar 121 which is a rotating mortar and an outer mortar 122 which is a fixed mortar. Solid raw materials to be ground are introduced from the introduction part 112 into the inlet part 123 between the inner mortar 121 and the outer mortar 122. The introduction part 112 is cylindrical, and the inner diameter of the lower end is substantially the same as the inner diameter of the outer mortar 122. The solid raw materials are, for example, cocoa nibs. Cocoa nibs are roasted cocoa beans that have been coarsely ground. Cocoa beans have an oil content of about 50% and a melting point of about 35°C.

In such a grinder 101, in order to grind the cocoa nibs 113, if the inner mortar 121 rotates, the cocoa nibs 113 are grinded by the inner mortar 121 and the outer mortar 122. In this case, when the cocoa nibs 113 exceeding the grinding capacity of the conical mortar 111 are put into the inlet 123, the cocoa nibs 113 that cannot be completely entered into the conical mortar 111 and the cocoa powder formed by the grinding of the cocoa nibs 113 by the conical mortar 111 flow back from the inlet 123 of the conical mortar 111 to the introduction part 112 as shown by the arrows in FIG. 10. In addition, the cocoa powder has heat due to being ground, and the conical mortar 111 has heat due to friction during the grinding action, and the heat of the conical mortar 111 is transferred to the introduction part 112. Therefore, the oil is dissolved from the cocoa powder, and the cocoa powder is accumulated on the inner surface of the introduction part 112 (the accumulated powder 114 in FIG. 10 ). As a result, the supply of the cocoa nibs 113 from the introduction part 112 to the conical mortar 111 cannot be smoothly performed.

Fig. 11 shows the state of general problems caused by the increase of the accumulated powder 114 shown in Fig. 10. Fig. 11 (a) shows the state where a rat hole is generated, Fig. 11 (b) shows the state where a bridge is generated, Fig. 11 (c) shows the state where agglomeration is generated, and Fig. 11 (d) shows the state where adhesion residue is caused.

An aspect of the present invention aims to realize a pulverizer capable of suppressing the accumulation of powder of a solid raw material when the solid raw material is introduced into the inner surface of an introduction portion of a conical mortar.

In order to solve the above-mentioned problem, a pulverizer of one embodiment of the present invention comprises: a pulverizing section, comprising a conical mortar including an inner mortar which is a rotating mortar and an outer mortar which is a fixed mortar, and a solid raw material containing oil to be fed into an inlet portion between the inner mortar and the outer mortar is pulverized by the conical mortar; and an introduction section, comprising an opening portion at the lower end portion, the diameter of the opening portion being smaller than the inner diameter of the outer mortar of the inlet portion, and the solid raw material to be supplied is fed into the inlet portion of the conical mortar from the opening portion.

According to one aspect of the present invention, it is possible to suppress accumulation of powder of a solid raw material when the solid raw material is introduced into the inner surface of the introduction portion of the conical mortar.

(Overview of pulverization of solid raw materials) The pulverization of solids such as cereals and beans has dramatically expanded its uses and is used for various foods. However, it is well known that it is difficult to grind uniform materials efficiently and prevent the deterioration of flavor. Not only does the grinding efficiency become uneven, the particles of the pulverized materials lose their smoothness for wheat flour, buckwheat flour, etc., and the quality of udon and buckwheat is reduced, but the excess heat applied during pulverization is also likely to cause oxidation and deterioration of flavor. When excess friction heat is applied to the pulverized materials during pulverization, the fresh flavor of tea is lost, and soy milk becomes a strong raw odor. The conventional idea of slowly rotating the mortar to grind the material is very reasonable in that it suppresses the generation of frictional heat and prevents the deterioration of the flavor of the material being processed.

The basic idea is the same even if the material of the so-called grinding method of adjusting the particle size of the ground material is changed from natural stone to ceramic or metal by the gap between the rotating grindstone and the fixed grindstone like a mortar. This is also true for dry grinding and wet grinding. Buckwheat fruit grinding in buckwheat production is done by dry method, and soybean grinding in tofu production is done by wet method. Grinding with a mortar method is used in various fields. Regardless of dry or wet method, the gap between the rotating grindstone and the fixed grindstone is adjusted and implemented so that the target particle size can be achieved in one stage. In addition, in a pulverizer made of metal such as stainless steel, the clearance between the rotating blade and the fixed blade is also designed and implemented so that the pulverized product has a target size by pulverizing in one stage.

For example, in the case of chocolate, cocoa beans are fermented, dried, roasted, and peeled to be processed into what are called cocoa nibs. When crushing in a chocolate workshop or other shop, the gap between the mortars is gradually adjusted using a mortar method. In order to obtain the desired smooth chocolate, it is necessary to repeat the crushing several times while gradually narrowing the gap. It is disadvantageous if the size of a single grain of cocoa, the raw material, is relatively large relative to the gap. In other words, since the cocoa is gradually finely crushed, it takes time to obtain the target particles.

In the grinding of cocoa, the melting point of cocoa is about 35℃. The friction heat between the mortar and the cocoa nibs during grinding is used to make the cocoa nibs liquid (paste), and wet grinding is adopted. The temperature of the cocoa and the mortar during grinding depends on the process and has not been controlled in the past. If the temperature is low, the cocoa beans cannot flow in the mortar and solidify in the groove, and cannot be ground, which increases the load on the motor. On the other hand, if the temperature is too high, the cocoa nibs will burn, and the quality of the cocoa beans will decrease.

[Implementation method 1] The following is a detailed description of an implementation method of the present invention. FIG. 1 is a perspective view of a pulverizing device 1 including a pulverizing unit 11 as a pulverizer of the present implementation method. FIG. 2 is a perspective view of the pulverizing unit 11 shown in FIG. 1. FIG. 3 is an exploded perspective view of the pulverizing unit 11 shown in FIG. 2. FIG. 4 is a perspective view including a longitudinal section of the pulverizing unit 11 shown in FIG. 2. FIG. 5 is a front view of a longitudinal section of the pulverizing unit 11 shown in FIG. 4.

(Overview of the pulverizing device 1) As shown in FIG1 , the pulverizing device 1 includes a pulverizing unit 11, a heat-insulating container 12, a hopper 13, a motor 14, and a powder extraction rod 15.

The grinding unit 11 is housed in a heat-insulating container 12, and a hopper 13 is mounted on the grinding unit 11. The hopper 13 houses a solid raw material. The present embodiment will be described with reference to a case where the solid raw material is cocoa nibs. The motor 14 is disposed at the bottom of the grinding device 1 to rotate the grinding portion 26 of the grinding unit 11. The powder extraction rod 15 is located at the side of the grinding device 1. The powder extraction rod 15 is rotated downward to extract the powder (cocoa powder) of the cocoa nibs crushed by the grinding unit 11 from the extraction port 16.

(Structure of the crushing unit 11) As shown in Figs. 2 to 5, the crushing unit 11 includes a housing 21 at the top and a recovery and conveying unit 22 at the bottom. The housing 21 includes a handle 23 used when the crushing unit 11 is put in and out of the heat-insulating container 12. Inside the housing 21, from top to bottom, a hopper receiving unit 24, an introduction unit 25, and a crushing unit 26 are provided.

The hopper receiving part 24 receives the hopper 13 disposed on the grinding unit 11. The hopper receiving part 24 includes an opening at the lower end. The hopper 13 contains cocoa nibs, and the introduction part 25 receives the cocoa nibs supplied from the hopper 13 through the hopper receiving part 24. The introduction part 25 includes an opening 25a at the lower end.

The grinding part 26 includes a conical mortar 27 in the center and a flat mortar 28 around the conical mortar 27. The conical mortar 27 includes an inner mortar 29 which is a rotating mortar and an outer mortar 30 which is a fixed mortar. The outer mortar 30 has a cylindrical shape, and the inner mortar 29 is inserted into the outer mortar 30, and has a shape in which the outer diameter gradually decreases from the bottom to the top. The inner side of the outer mortar 30 at the upper end of the conical mortar 27 serves as an inlet 33 for cocoa nibs. The conical mortar 27 grinds the cocoa nibs 45 (refer to FIG. 6 , solid raw materials) introduced from the introduction part 25 into coarse cocoa powder.

The flat mortar 28 includes a lower mortar 31 which is a rotating mortar and an upper mortar 32 which is a fixed mortar. The lower mortar 31 is fixed to the outer periphery of the inner mortar 29 and is integrated with the inner mortar 29. The upper mortar 32 is fixed to the outer periphery of the outer mortar 30 and is integrated with the outer mortar 30. A central axis 37 is provided at the center of the inner mortar 29 and the lower mortar 31. The flat mortar 28 pulverizes the coarse cocoa powder formed by the conical mortar 27 into fine cocoa powder.

The recovery conveying section 22 includes a material receiving section 34 at the upper part, a conveying passage 35 connected to the material receiving section 34, and a driving transmission section 36 below the material receiving section 34. The crushing section 26 is arranged above the material receiving section 34, and the material receiving section 34 receives the cocoa powder formed by the crushing section 26. The conveying passage 35 conveys the cocoa powder received by the material receiving section 34 downward. The driving transmission section 36 transmits the driving force of the motor 14 to the central axis 37 of the crushing section 26 placed on the material receiving section 34, so that the crushing section 26 (the inner mortar 29 and the lower mortar 31) rotates.

4 and 5 show a state in which the inner mortar 29 of the conical mortar 27 is provided with the adhesion prevention and stirring member 44 described in FIG. 7 .

(Detailed structure, operation and advantages of the crushing unit 11) FIG. 6 is an explanatory diagram showing the detailed structure of the crushing unit 11 shown in FIG. 5 and the operation of the crushing unit 11.

As shown in FIG6 , the diameter of the opening 25a of the introduction part 25 is smaller than the inner diameter of the outer mortar 30 of the entrance part 33 of the conical mortar 27. In the entrance part 33 of the conical mortar 27, the rotational force of the inner mortar 29 spreads the cocoa nibs 45 and the cocoa nibs 45 in the introduction part 25 are also moved. However, due to the above-mentioned structure, the cocoa nibs 45 put into the entrance part 33 of the conical mortar 27 and the cocoa powder formed by crushing the cocoa nibs 45 rotate in a small range in the entrance part 33 of the conical mortar 27 below the introduction part 25, and it becomes difficult to flow back to the introduction part 25, and the range of the rotational force diffusion can be suppressed. This is because the lower surface of the introduction part 25 becomes a so-called return, and the backflow of the cocoa nibs 45 and the cocoa powder to the introduction part 25 is suppressed. In addition, the friction between the cocoa nibs 45 can be reduced, and the generation of cocoa powder in the introduction part 25 can be suppressed. As a result, the accumulation of cocoa powder (powder of solid raw material) in the introduction part 25 can be suppressed, and the cocoa nibs 45 can be smoothly introduced from the introduction part 25 into the conical mortar 27. In addition, in the conical mortar 27, the backflow of the introduced cocoa nibs 45 to the introduction part 25 can be suppressed by the lower surface of the introduction part 25, and the introduced cocoa nibs 45 can be efficiently crushed.

Furthermore, the inner diameter of the introduction part 25 gradually decreases from the upper part toward the opening part 25a. That is, the inner surface of the introduction part 25 is an inclined surface whose diameter gradually decreases from the upper part toward the opening part 25a. The cocoa nibs 45 receive the rotational force diffused from the inlet part 33 of the conical mortar 27, and also rotate (rotate) in the introduction part 25 near the opening part 25a. The force that moves in the centrifugal (outward) direction by this rotation acts on the cocoa nibs 45, and the cocoa nibs 45 and the cocoa powder are pressed against the inner surface of the introduction part 25, and the cocoa powder is accumulated in a pressed and fixed manner. Therefore, the introduction part 25 includes an inclined surface, whereby the cocoa powder moves upward and avoids the force pressing the inner surface of the introduction part 25. Therefore, even if the cocoa powder has returned from the conical mortar 27 to the introduction part 25, the cocoa powder easily moves upward along the inclined surface of the introduction part 25, and it becomes difficult to accumulate at one place near the opening 25a of the introduction part 25.

The inclination angle relative to the horizontal plane of the inner surface of the introduction part 25 is preferably 45°>θ>75° if the inclination angle is set to θ. If the inclination angle θ is set to 45° or less, the diameter of the introduction part 25 becomes too large, and the cocoa nibs may remain on the inclined surface. On the other hand, if the inclination angle θ is set to 75° or more, the effect of releasing the force of the centrifugal force that presses and tightens the cocoa powder due to the rotation upward becomes less. Therefore, the cocoa powder that has returned from the conical mortar 27 to the introduction part 25 is difficult to move upward from the introduction part 25, and is easy to accumulate near the opening 25a.

The relationship between the inner diameter of the outer mortar 30 of the entrance portion 33 of the conical mortar 27 and the diameter of the opening portion 25a of the introduction portion 25 is preferably 0.5>d1/D1>0.8 if the inner diameter of the outer mortar 30 of the entrance portion 33 is set to D1 and the diameter of the opening portion 25a of the introduction portion 25 is set to d1. (Request item 3) The relationship between the gap between the lower surface of the introduction portion 25 and the upper surface of the inner mortar 29 and the outer diameter of the upper end of the inner mortar 29 is preferably 0.5>2h1/(D1-D2)>1 if the gap between the lower surface of the introduction portion 25 and the upper surface of the inner mortar 29 is set to gap h1 and the outer diameter of the upper end of the inner mortar 29 is set to D2.

If 2h1/(D1-D2) is less than 0.5, it becomes difficult for the cocoa nibs 45 to enter between the inner mortar 29 and the outer mortar 30 of the conical mortar 27. On the other hand, if 2h1/(D1-D2) is greater than 1, the cocoa nibs 45 introduced from the introduction section 25 into the inlet section 33 tend to return to the introduction section 25.

[Implementation Method 2] Other implementation methods of the present invention are described below. In addition, for the convenience of explanation, the same symbols are given to the components having the same functions as the components described in the above implementation methods, and their descriptions are not repeated.

(Detailed structure, operation and advantages of the crushing unit 11) Figure 7 is an explanatory diagram showing the detailed structure of the crushing unit 11 of this embodiment and the operation of the crushing unit 11.

As shown in FIG. 7 , the pulverizing unit 11 of the present embodiment includes a rotatable adhesion prevention protrusion member 41 between the inner mortar 29 and the outer mortar 30 of the conical mortar 27. The adhesion prevention protrusion member 41 has one end portion fixed to the upper surface of the inner mortar 29 by a screw, and the other end portion is bent obliquely downward so as to enter between the inner mortar 29 and the outer mortar 30. The other end portion of the adhesion prevention protrusion member 41 is used to scrape off the accumulated powder 42 caused on the inner peripheral surface of the outer mortar 30. Thus, in the pulverizing unit 11, it is possible to suppress the decrease in the pulverizing efficiency in the conical mortar 27 caused by the accumulation of powder 42 in the conical mortar 27.

If the cocoa nibs 45 are ground for a long time in the conical mortar 27, powder 42 is accumulated on the inner peripheral surface of the outer mortar 30 at the inlet 33, and the grinding efficiency in the conical mortar 27 is reduced. The reason why the powder 42 is accumulated is that, as in the case described with reference to FIG. 10 , the cocoa powder generates heat by being ground, and the conical mortar 27 generates heat by friction during the grinding operation, and the oil is dissolved from the cocoa powder by the heat, and the cocoa powder is accumulated on the inner peripheral surface of the outer mortar 30 at the inlet 33. Therefore, in the grinding unit 11 of the present embodiment, the inner mortar 29 is provided with the adhesion preventing protrusion member 41, and the accumulated powder 42 is scraped off by the adhesion preventing protrusion member 41 rotating together with the inner mortar 29.

In addition, the adhesion preventing projection member 41 is not limited to a structure that is provided on the mortar 29 and rotates together with the mortar 29, and may be a structure that is driven to rotate by other mechanisms.

[Third embodiment] Another embodiment of the present invention is described below. In addition, for the convenience of explanation, the same symbols are given to the components having the same functions as the components described in the above embodiments, and their descriptions are not repeated.

(Detailed structure, operation and advantages of the crushing unit 11) Figure 8 is an explanatory diagram showing the detailed structure of the crushing unit 11 of this embodiment and the operation of the crushing unit 11. Figure 9 is a three-dimensional diagram showing the attachment prevention and installation state of the stirring member 44 to the inner mortar 29 of the conical mortar 27.

As shown in FIG8 , the pulverizing unit 11 of the present embodiment includes a rotating rod-shaped stirring member 43 provided in the moving path of the cocoa nibs 45 to the introduction portion 25. In the present embodiment, the stirring member 43 is connected to one end of the adhesion preventing protrusion member 41 and is configured as a part of the adhesion preventing and stirring member 44 including the adhesion preventing protrusion member 41 and the stirring member 43.

The stirring member 43 is inserted into the inside of the introduction part 25 from the opening 25a of the introduction part 25 and reaches the lower part of the funnel receiving part 24. The stirring member 43 is provided in the inner mortar 29 and rotates together with the inner mortar 29. Thus, the cocoa nibs 45 are prevented from being retained in the moving path of the cocoa nibs 45 to the introduction part 25, and the cocoa nibs 45 are smoothly put into the conical mortar 27 through the introduction part 25.

In addition, the stirring member 43 is not limited to being provided as a part of the adhesion prevention and stirring member 44, but may be provided separately. In addition, the stirring member 43 is not limited to being provided in the mortar 29 and rotating together with the mortar 29, but may be driven and rotated by other mechanisms.

[Summary] The pulverizer of scheme 1 of the present invention comprises: a pulverizing section, comprising a conical mortar including an inner mortar as a rotating mortar and an outer mortar as a fixed mortar, wherein a solid raw material containing oil to be fed into an inlet portion between the inner mortar and the outer mortar is pulverized by the conical mortar; and an introduction section, comprising an opening at a lower end portion, wherein the diameter of the opening is smaller than the inner diameter of the outer mortar at the inlet portion, wherein the solid raw material to be fed is fed into the inlet portion of the conical mortar from the opening.

The pulverizer of the second aspect of the present invention may also be configured as follows: in the first aspect, the inner diameter of the introduction portion gradually decreases from the upper portion toward the opening portion.

The pulverizer of Scheme 3 of the present invention may also be configured as follows: In Scheme 1 or 2 above, if the inner diameter of the outer mortar of the inlet portion is set to D1, and the diameter of the opening of the introduction portion is set to d1, then 0.5>d1/D1>0.8 holds true.

The grinder of Scheme 4 of the present invention can also be configured as follows: in any of Schemes 1 to 3 above, if the gap between the lower surface of the introduction portion and the upper surface of the mortar is set to gap h1, and the outer diameter of the upper end portion of the mortar is set to D2, then 0.5>2h1/(D1-D2)>1 holds.

The pulverizer of scheme 5 of the present invention may also be configured as follows: in any one of schemes 1 to 4 above, if the inclination angle of the inner surface of the introduction portion is set to θ, then 45°>θ>75° holds true.

The pulverizer of claim 6 of the present invention may also be configured as follows: In any one of claims 1 to 5, a rotatable adhesion preventing protrusion member is included between the outer mortar and the inner mortar.

The pulverizer of Scheme 7 of the present invention may also be configured as follows: in any one of Schemes 1 to 6 above, it includes: a hopper, which is above the introduction portion and supplies the solid raw material to the introduction portion; and a rotating rod-shaped stirring component which is arranged on the path of the solid raw material to the introduction portion.

1: Crushing device 11: Crushing unit (crusher) 13: Funnel 22: Recovery and conveying part 24: Funnel receiving part 25: Introducing part 25a: Opening part 26: Crushing part 27: Conical mortar 28: Flat mortar 29: Inner mortar 30: Outer mortar 31: Lower mortar 32: Upper mortar 33: Inlet 34: Material receiving part 35: Conveying passage 41: Attachment prevention protrusion part 42: Powder accumulation 43: Stirring part 44: Attachment prevention and stirring part 45: Cocoa nibs (solid raw material)

FIG. 1 is a perspective view of a pulverizing device including a pulverizing unit of a pulverizer as an embodiment of the present invention. FIG. 2 is a perspective view of the pulverizing unit shown in FIG. 1. FIG. 3 is an exploded perspective view of the pulverizing unit shown in FIG. 2. FIG. 4 is a perspective view including a longitudinal section of the pulverizing unit shown in FIG. 2. FIG. 5 is a front view of a longitudinal section of the pulverizing unit shown in FIG. 4. FIG. 6 is an explanatory diagram showing the detailed structure of the pulverizing unit shown in FIG. 5 and the operation of the pulverizing unit. FIG. 7 is an explanatory diagram showing the detailed structure of the pulverizing unit of another embodiment of the present invention and the operation of the pulverizing unit. FIG. 8 is an explanatory diagram showing the detailed structure of the pulverizing unit of another embodiment of the present invention and the operation of the pulverizing unit. FIG9 is a perspective view showing the installation state of the adhesion prevention and stirring parts for the inner mortar of the conical mortar shown in FIG8. FIG10 is a longitudinal sectional view showing the structure of the main parts of the conventional pulverizer. FIG11 is a diagram showing the state of general problems caused by the increase of the accumulated powder shown in FIG10, FIG11 (a) is the state of the guide hole, FIG11 (b) is the state of the bridge, FIG11 (c) is the state of the agglomeration, and FIG11 (d) is the state of the adhesion residue.

25: Introduction

25a: Opening

26: Crushing Department

27: Conical mortar

28: Mortar

29: acetabulum

30: External mortar

31: Lower mortar

32: Upper Mortar

33: Entrance

37: Center axis

45: Cocoa nibs (solid raw material)

D1: Inner diameter of the outer mortar at the entrance

d1: The diameter of the opening of the introduction part

h1: Gap

θ: Tilt angle

D2: The outer diameter of the upper end of the acetabulum

Claims (7)

A pulverizer includes: a pulverizing section having a conical mortar composed of an inner mortar as a rotating mortar and an outer mortar as a fixed mortar, wherein a solid raw material having oil content is fed into an inlet between the inner mortar and the outer mortar and is pulverized by the conical mortar; and an introduction section having an opening at the lower end, wherein the diameter of the opening is smaller than the inner diameter of the outer mortar of the inlet, and the solid raw material to be supplied is fed into the inlet of the conical mortar from the opening; the wall surface constituting the introduction section includes: a planar lower surface extending laterally from the opening; and a cylindrical inner surface inclined in such a manner that the inner diameter of the introduction section gradually decreases from the upper portion toward the opening, wherein the lower surface covers the entire surface of the inlet of the conical mortar, and in the introduction section, the inner surface and the lower surface form a sharp angle. A pulverizer as described in claim 1, wherein the inner diameter of the introduction portion gradually decreases from the upper portion toward the opening portion. A grinder as claimed in claim 1 or 2, wherein if the inclination angle of the inner surface of the introduction portion is set to θ, then 45°<θ<75° holds true. A grinder as described in claim 1 or 2, wherein a rotating attachment preventing protrusion component is included between the outer mortar and the inner mortar. A pulverizer, comprising: a pulverizing section having a conical mortar composed of an inner mortar as a rotating mortar and an outer mortar as a fixed mortar, wherein a solid raw material having oil content is fed into an inlet between the inner mortar and the outer mortar and pulverized by the conical mortar; and an introduction section having an opening at a lower end, wherein the diameter of the opening is smaller than the inner diameter of the outer mortar at the inlet, wherein the solid raw material to be fed is fed into the inlet of the conical mortar from the opening; The wall surface constituting the introduction part includes: a planar lower surface extending laterally from the opening; and a cylindrical inner surface inclined in a manner such that the inner diameter of the introduction part gradually decreases from the upper part toward the opening. The lower surface covers the entire surface of the entrance part of the conical mortar. If the inner diameter of the outer mortar of the entrance part is set to D1 and the diameter of the opening of the introduction part is set to d1, then 0.5<d1/D1<0.8 holds true. A pulverizer comprises: a pulverizing section having a conical mortar composed of an inner mortar as a rotating mortar and an outer mortar as a fixed mortar, wherein a solid raw material having oil content is fed into an inlet between the inner mortar and the outer mortar and is pulverized by the conical mortar; and an introduction section having an opening at a lower end, wherein the diameter of the opening is smaller than the inner diameter of the outer mortar at the inlet, wherein the solid raw material to be fed is fed into the inlet of the conical mortar from the opening; and The wall surface includes: a planar lower surface extending laterally from the opening; and a cylindrical inner surface inclined in a manner such that the inner diameter of the introduction portion gradually decreases from the upper portion toward the opening, and the lower surface covers the entire surface of the entrance portion of the conical mortar. If the gap between the lower surface of the introduction portion and the upper surface of the inner mortar is set to gap h1, and the outer diameter of the upper end of the inner mortar is set to D2, then 0.5<2h1/(D1-D2)<1. A pulverizer, comprising: a pulverizing section having a conical mortar composed of an inner mortar as a rotating mortar and an outer mortar as a fixed mortar, wherein a solid raw material having oil content is fed into an inlet between the inner mortar and the outer mortar and pulverized by the conical mortar; and an introduction section having an opening at the lower end, wherein the diameter of the opening is smaller than the inner diameter of the outer mortar at the inlet, wherein the solid raw material to be fed is fed into the inlet of the conical mortar from the opening; the wall of the introduction section is The pulverizer includes: a planar lower surface extending laterally from the opening; and a cylindrical inner surface inclined in a manner that the inner diameter of the introduction portion gradually decreases from the upper portion toward the opening portion, and the lower surface covers the entire surface of the inlet portion of the conical mortar. The pulverizer also includes: a hopper on the introduction portion to supply the solid raw material to the introduction portion; and a stirring component, which is arranged on the path of the solid raw material to reach the introduction portion and is in the shape of a rotating rod.