APPARATUS FOR PRESSING CHEEK PLATES AND APPARATUS FOR MANUFACTURING COMPACTED IRONS COMPRISING THE SAME

Technical Field The present invention relates to an apparatus for pressing cheek plates and an apparatus for manufacturing compacted iron including the same, and more specifically to an apparatus for pressing cheek plates that prevents direct reduced iron from being scattered through the cheek plate and an apparatus for manufacturing compacted iron including the same. Background Art

Since a blast furnace method for producing molten iron has a lot of problems such as environment pollution, a smelting reduction process, which can replace the blast furnace method, has been researched. In the smelting reduction process, raw coal is directly used as a fuel and a reducing agent and iron ore is directly used as an iron source, and thereby molten iron is manufactured. After the iron ore is converted into reduced iron in a reduction reactor, the reduced iron is charged into a melter-gasifier. Then, the reduced iron is melted therein, and thereby molten iron is manufactured.

Here, direct reduced iron DRI is compressed to the compacted iron by using an apparatus for manufacturing compacted iron and then the compacted iron is charged into the melter-gasifier in order to secure permeability therein. The apparatus for manufacturing compacted iron includes a pair of rolls. The direct reduced iron enters into a gap formed between the pair of rolls and is then compressed therein, and thereby the compacted iron is manufactured. Meanwhile, when the direct reduced iron is compressed, the direct reduced iron can be scattered outside since a strong pressure is applied to the pair of rolls. Therefore, cheek plates are installed at both ends of the gap, thereby preventing the direct reduced iron from being scattered. DISCLOSURE

Technical Problem

An apparatus for pressing cheek plates for efficiently preventing

direct reduced iron from being scattered is provided. In addition, an apparatus for manufacturing compacted iron including the above described apparatus for pressing cheek plates is provided. Technical Solution An apparatus for pressing cheek plates according to an embodiment of the present invention includes i) a bar that is configured to press a cheek plate installed at one end of a gap formed between a pair of rolls that compress direct reduced iron and manufacture compacted iron, to the gap; ii) a piston that is configured to press and push the bar to the gap; and iii) a cylinder that receives the piston. The piston is configured to move along a direction in which the bar is extended by a pressure of an inner space of the cylinder.

The inner space of the cylinder may include first and second spaces. The first and second spaces may be separated from each other by the piston, and the first space may be closer to the bar than the second space. Air may enter into the second space and then press the piston to the gap. The air in the first space may be ventilated to the outside of the cylinder from the first space when the air enters into the second space.

An apparatus for pressing cheek plates according to an embodiment of the present invention may further include i) an air compressor that supplies air to the second space; and ii) a control valve that provides the air supplied from the air compressor to the second space and ventilates the air in the first space to the outside of the cylinder at the same time.

An apparatus for pressing cheek plates according to an embodiment of the present invention may further include i) an air compressor that supplies air to the first space; and ii) a control valve that provides the air supplied from the air compressor to the first space and ventilates the air in the second space to the outside of the cylinder at the same time.

An apparatus for pressing cheek plates according to an embodiment of the present invention may further include i) a supporting member through which the bar is penetrated; ii) a rotating member that is hinge-combined with the supporting member based on an axis extended along a direction

crossing a direction along which the bar is extended; and iii) a jaw that is located between the piston and one end of the bar. The supporting member supports and fixes the bar, and the rotating member is provided with a penetrated opening through which the piston is penetrated. The rotating member may be located between the supporting member and the cylinder, and is fixed to combine with the cylinder.

An apparatus for pressing cheek plates according to an embodiment of the present invention may further include a dust cover that is combined with the jaw and covers the jaw and the piston. A concave groove may be formed at the one end of the bar. The jaw may include a protruding portion directed to the concave groove. The protruding portion may be inserted into the concave groove. An apparatus for pressing cheek plates according to an embodiment of the present invention may further include a bolt that is inserted into a screw opening formed in the protruding portion and the screw groove formed in the piston. The jaw and the piston may be combined together by the bolt. The diameter of the penetrated opening may be less than the diameter of the jaw.

An apparatus for manufacturing compacted iron according to an embodiment of the present invention includes i) a pair of rolls that compress direct reduced iron and manufacture compacted iron; ii) a cheek plate that is installed at one end of a gap formed between the pair of rolls; iii) a casing that receives the pair of rolls and the cheek plate; and iv) at least one apparatus for pressing cheek plates that is configured to be installed at an outer surface of the casing to press the cheek plate to the gap. The apparatus for pressing cheek plates includes i) a bar that is configured to press the cheek plate to the gap while penetrating the casing; ii) a piston that is configured to press and push the bar to the gap; and iii) a cylinder that receives the piston. The piston is configured to move along a direction in which the bar is extended by a pressure of an inner space of the cylinder. The inner space of the cylinder may include first and second spaces.

The first and second spaces may be separated from each other by the piston. The first space may be closer to the bar than the second space. Air may

enter into the second space and then press the piston to the gap. The air in the first space may be ventilated to the outside of the cylinder from the first space when the air enters into the second space.

An apparatus for manufacturing compacted iron according to an embodiment of the present invention may further include i) an air compressor that supplies air to the second space; and ii) a control valve that provides the air supplied from the air compressor to the second space and ventilates the air in the first space to the outside of the cylinder at the same time. The at least one apparatus for pressing cheek plates may include a plurality of apparatuses for pressing cheek plates, and the number of control valves is one.

An apparatus for manufacturing compacted iron according to an embodiment of the present invention may further include i) an air compressor that supplies an air to the first space; and ii) a control valve that provides the air supplied from the air compressor to the first space and ventilates the air in the second space to the outside of the cylinder at the same time.

An apparatus for manufacturing compacted iron according to an embodiment of the present invention may further include i) a supporting member through which the bar is penetrated; ii) a rotating member that is hinge-combined with the supporting member based on an axis extended along a direction crossing a direction in which the bar is extended; and iii) a jaw that is located between the piston and one end of the bar. The supporting member may support and fix the bar and is fixed on the outer surface of the casing. The piston is penetrated through the rotating member. The rotating member may be located between the supporting member and the cylinder, and be fixed to combine with the cylinder. Advantageous Effects

Since a bar is pressed by using air pressure, a gap formed between the pair of rolls is sealed by the cheek plates and then the direct reduced iron is prevented from being scattered.

DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic perspective view of the apparatus for manufacturing compacted iron according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view along a line II-II of FIG. 1.

FIG. 3 is a schematic view illustrating a state in which the cheek plates are pressed by the apparatus for pressing cheek plates according to an embodiment of the present invention.

FIG. 4 is a schematic view illustrating a state in which the apparatus for pressing cheek plates according to an embodiment of the present invention is released.

FIG. 5 is a partial exploded view of the apparatus for pressing cheek plates of FIG. 1.

FIG. 6 is a combined view of the apparatus for pressing cheek plates of FIG. 5.

FIG. 7 is a schematic cross-sectional view cutting along a line VII-VII of FIG. 6.

FIG. 8 is a schematic view illustrating a state in which the apparatus for pressing cheek plates of FIG. 2 is disassembled. BEST MODE

Exemplary embodiments of the present invention will be explained in detail below with reference to the attached drawings in order for those skilled in the art in the field of the present invention to easily perform the present invention. However, the present invention can be realized in various forms and is not limited to the embodiments explained below. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

All terms including technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of

the relevant art and the present disclosure, and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The direct reduced iron means reduced materials containing iron. The materials containing iron may be iron itself or all materials containing iron. For example, the materials containing iron may further contain additives. The materials containing iron include iron ore. In addition, the iron can be pure iron, oxidized iron, or reduced iron. A reducing ratio of the reduced iron is not limited. Therefore, the reduced iron may be partly reduced or completely reduced. FIG. 1 is a schematic perspective view of an apparatus for manufacturing compacted iron 100 according to an embodiment of the present invention. A structure of the apparatus for manufacturing compacted iron 100 shown in FIG. 1 is merely to illustrate the present invention and the present invention is not limited thereto. Therefore, the structure of the apparatus for manufacturing compacted iron 100 can be modified into other forms. For example, direct reduced iron can enter into a gap between a pair of rolls 20 without using a charging hopper 10.

As shown in FIG. 1, the apparatus for manufacturing compacted iron 100 includes a charging hopper 10, a pair of rolls 20 (shown in FIG. 2, the same hereinafter), and an apparatus for pressing cheek plates 90. Here, the apparatus for pressing cheek plates 90 includes first, second, and third apparatuses for pressing cheek plates 901, 902, and 903. The first, second, and third apparatuses for pressing cheek plates 901, 902, and 903 press the cheek plates 80 (shown in FIG. 2, the same hereinafter) at positions of apexes of a triangle. That is, since a shape of the cheek plate 80 is similar to a triangle, all surfaces of the cheek plate 80 can be uniformly pressed if the cheek plate 80 is pressed with a form of a triangle. Therefore, the cheek plate 80 is closely adhered to the pair of rolls 20, and thereby direct reduced iron does not leak. The direct reduced iron is charged into the charging hopper 10 through an opening 16 located at a center thereof along a direction indicated by an arrow. A ventilation opening 14 is formed at an upper side of the

charging hopper 10. Gas generated from the direct reduced iron entering into the charging hopper 10 is ventilated outside of the charging hopper 10 through the ventilation opening 14.

As shown in FIG. 1, screw feeders 12 are installed to be slanted at an acute angle in the charging hopper 10. The screw feeders 12 rotate to transfer the direct reduced iron to a gap formed between the pair of rolls 20 by force. Therefore, compressive density of the direct reduced iron can be increased by the screw feeder 12.

The pair of rolls 20 rotate to be combined with each other by the gear 26. The pair of rolls 20 are received in a casing 24. The pair of rolls 20 compress the direct reduced iron and manufacture compacted iron, and discharge them to the outside.

The apparatus for pressing cheek plates 90 is installed at an outer surface of the casing 24 in order to press the cheek plates 80 installed at both ends of the gap formed between the pair of rolls 20. Therefore, the direct reduced iron can be prevented from being scattered and leak from the apparatus for manufacturing compacted iron 100.

FIG. 2 schematically shows a cross-sectional structure along a line II- II of FIG. 1. As shown in FIG. 2, the screw feeder 12 is provided with a scraper

124. When the screw feeder 12 rotates, the scraper 124 rotates with the screw feeder 12 while removing direct reduced iron adhered to an inner wall of the charging hopper 10. Therefore, the direct reduced iron is prevented from being attached to and stacked on the inner wall of the charging hopper 10.

As shown in FIG. 2, the apparatus for pressing cheek plates 90 is installed at an outer surface of the casing 24 and then presses the cheek plate 80. Therefore, the direct reduced iron is prevented from being scattered from the pair of rolls 20. As shown in FIG. 2, the apparatus for pressing cheek plates 90 includes a bar 91. Since the bar 91 is pressed to the gap, the cheek plate 80 can be closely adhered to the pair of rolls 20. Therefore, the direct reduced

iron is prevented from leaking and being scattered from the apparatus for manufacturing compacted iron 100.

The apparatus for pressing cheek plates 90 according to an embodiment of the present invention presses the cheek plate 80 by using air pressure. Therefore, the pressing force can be largely increased compared to a case in which the cheek plate 80 is pressed by mechanical combination. When the compacted iron is manufactured from the apparatus for manufacturing compacted iron 100, large vibration occurs. As a result, mechanical combination between components of the apparatus for pressing cheek plates 90 can be weakened. For example, as a bolt, which combines the elements together, is released, pressing force to the cheek plate 80 is weakened. Therefore, a gap is formed between the pair of rolls 20 and the cheek plate 80, thereby the direct reduced iron can be scattered.

On the contrary, the apparatus for pressing cheek plates 90 using air pressure is provided in an embodiment of the present invention. Therefore, since the apparatus for pressing cheek plates 90 presses the cheek plate 80 by air supplied from the outside, the apparatus for pressing cheek plates 90 is not influenced by a vibration of the apparatus for manufacturing compacted iron 100. Therefore, the cheek plate 80 can be continuously pressed by the apparatus for pressing cheek plates 90.

As shown in FIG. 2, the apparatus for pressing cheek plates 90 includes a cylinder 94, a control valve 51, an air compressor 98, and an air storage tank 99. The air compressor 98 supplies air to the inside of the cylinder 94, thereby pressing the cheek plate 80 by the bar 91. The air is supplied to the air compressor 98 from the air storage tank 99. The control valve 51 is connected to the cylinder 94 and the air compressor 98, thereby controlling input and output of the air. An operating state of the apparatus for pressing cheek plates 90 by air pressure will be described in more detail with reference to FIGs. 3 and 4. FIG. 3 is a schematic view showing a state in which the cheek plate 80

(shown in FIG. 2, the same hereinafter) is pressed by the apparatus for pressing cheek plates 90. FIG. 3 shows a state in which first, second, and

third apparatuses for pressing cheek plates 901, 902, and 903 are controlled together.

Since the first and second apparatuses for pressing cheek plates 901 and 902 are located side by side along an x-axis direction, they are operated together by using the same control valve 51. As a result, the cheek plate 80 can be stably pressed. Since the third apparatus for pressing cheek plates 903 is located below the first and second apparatuses for pressing cheek plates 901 and 902, another control valve 53 is used. Therefore, the entire surface of the cheek plate 80 can be uniformly pressed. As shown in FIG. 3, the cylinder 94 receives the piston 941. The piston 941 can be moved along a direction indicated by an arrow, that is, a y- axis direction, by a pressure of the inner space of the cylinder 94. Here, the y-axis direction means a direction that the bar 91 (shown in FIG. 2, the same hereinafter) is extended. Therefore, the cheek plate 80 can be stably pressed. The cylinder 94 includes first and second spaces 947 and 949 that are separated from each other by the piston 941. The first and second spaces 947 and 949 are separated from each other by the piston 941. The first and second spaces 947 and 949 are connected to first and second air tubes 944 and 945, respectively. The first and second air tubes 944 and 945 are opened and closed by passing through the control valves 51 and 53. The first air tube 944 is connected to the air compressor 95, thereby supplying the air to the first space 947.

Although not shown in FIG. 3, the first space 947 is closer to the bar 91 compared to the second space 949. Therefore, air is supplied to the second space 949 through the second air tube 945 by operating the control valves 51 and 53, and thereby the piston 941 can be pressed along a direction indicated by an arrow. The air is supplied from the air compressor 98. Simultaneously, air of the first space 947 is ventilated outside of the cylinder 94 through the first air tube 944. FIG. 4 is a schematic view showing a state in which the apparatus for pressing cheek plates 90 is released. Since FIG. 4 is similar to FIG. 3, like reference numerals refer to like elements and a detailed description thereof is

omitted.

As shown in FIG. 4, when the apparatus for manufacturing compacted iron 100 (shown in FIG. 1, the same hereinafter) is amended, the apparatus for pressing cheek plates 90 is firstly disassembled. For this, a pressing state of the apparatus for pressing cheek plates 90 is firstly released.

That is, the control valves 51 and 53 are converted, and thereby the air is supplied to the first space 947 through the first air tube 944. The air compressor 98 supplies the air to the first space 947. Simultaneously, the air of the second space 949 is ventilated to the outside through the second air tube 945. As a result, the piston 941 is moved along a direction indicated by an arrow (y-axis direction), and thereby the apparatus for pressing cheek plates 90 is released. Therefore, the apparatus for pressing cheek plates 90 can be easily removed from the apparatus for manufacturing compacted iron 100. FIG. 5 shows a partly disassembled apparatus for pressing cheek plates 90 according to an embodiment of the present invention. The air compressor 98 (shown in FIG. 2) and the air storage tank 99 (shown in FIG. 2) are omitted in FIG. 5 for convenience. In addition, the bar 91 and the cylinder 94 are shown to be partly cut for detailed explanation. As shown in FIG. 5, the apparatus for pressing cheek plates 90 includes a bar 91, a supporting member 92, a jaw 95, a dust cover 96, a rotating member 93, a piston 941, and a cylinder 94. In addition, the apparatus for pressing cheek plates 90 may further include other necessary components. The bar 91 has a stick shape to be extended along one direction (y- axis direction). Since the apparatus for pressing cheek plates 90 includes the bar 91, many components of the cheek plate 80 (shown in FIG. 2, the same hereinafter) can be pressed by the bar 91. A concave groove 911 is formed on one end of the bar 91. A protruding portion 951 of the jaw 95 is inserted into the concave groove 911. Therefore, the bar 91 and the jaw 95 are combined with each other. The other end of the bar 91 contacts the cheek plate 80 while pressing and supporting the cheek plate 80.

As shown in FIG. 5, the bar 91 penetrates a penetrated opening 926 formed in the supporting member 92. Therefore, the supporting member 92 can support and fix the bar 91. A bolt 923 is inserted into a screw opening 924 formed in the supporting member 92, and thereby the supporting member 92 is fixed on the casing 24 (shown in FIG. 2). In addition, a hinge opening 925 is formed in the supporting member 92 in order for a hinge 934 to be inserted. Therefore, the supporting member 92 and the rotating member 93 are combined with each other by the hinge 934.

The jaw 95 is located between the one end of the bar 91 and the piston 941 to connect them with each other. The jaw 95 includes a protruding portion 951 directed to the concave groove 911 of the bar 91. A screw opening 9511 is formed in the protruding portion 951. A bolt 953 is inserted into the screw opening 9511. The bolt 953 is inserted into the screw groove formed in the piston 9411, thereby combining the jaw 95 and the piston 9411 together. Therefore, a pressing force can act on the cheek plate 80 by consequently using the piston 9411, the jaw 95, and the bar 91.

The dust cover 96 is combined with the jaw 95. The dust cover 96 covers the jaw 95 and the piston 941, and thereby the direct reduced iron, which is scattered around the cheek plate 80, is prevented from entering into the cylinder 94. Therefore, the cylinder 94 can be stably protected.

As shown in FIG. 5, the rotating member 93 is located between the supporting member 92 and the cylinder 94. The rotating member 93 is combined with the supporting member 92 by the hinge 934. More specifically, the rotating member 93 is hinge-combined with the supporting member 92 based on an axis extended along a direction (x-axis direction) crossing a direction along which the bar 91 is extended (y-axis direction). Therefore, the rotating member 93 can rotate to upper and lower directions.

The rotating member 93 has a penetrated opening 935 through which the piston 941 penetrates. The piston 941 penetrates the rotating member 93 through the penetrated opening 935 to be combined with the jaw 95. Screw openings 938 are formed in the rotating member 93. Therefore, the bolts 937 are inserted into the screw openings 938 of the rotating member 93 and the

screw openings 942 of the cylinder 94, and thereby the rotating member 93 can be fixed to combine with the cylinder 94. As a result, since the rotating member 93 can stably support the piston 941 received in the cylinder 94, the piston 941 pushes the bar 91 well, and thereby the pressing force of the piston 941 can be transferred well.

FIG. 6 shows a combined apparatus for pressing cheek plates 90 of FIG. 5.

As shown in FIG. 6, the apparatus for pressing cheek plates 90 can be fixed on an outer surface of the casing 24 of the apparatus for manufacturing compacted iron 100 (shown in FIG. 1) by using bolts 923. Therefore, even if a large vibration occurs by operating the apparatus for manufacturing compacted iron 100, a position of the apparatus for pressing cheek plates 90 is stably maintained.

Meanwhile, as shown in FIG. 6, the rotating member 93 has a bending structure to cover side surfaces of the jaw 95 (shown in FIG. 5) and the dust cover 96 (shown in FIG. 5). Therefore, the direct reduced iron, which is scattered from the cheek plate 80 (shown in FIG. 2), is initially prevented from entering into the cylinder 94 by the rotating member 93.

FIG. 7 shows a schematic cross-sectional structure of the apparatus for pressing cheek plates 90 cutting along a line VII-VII of FIG. 6.

As shown in FIG. 7, a diameter d2 of the penetrated opening 935 of the rotating member 93 is less than a diameter di of the jaw 96. Therefore, the jaw 96 is limited in movement by the rotating member 93. As a result, when the apparatus for pressing cheek plates 90 is disassembled, a consuming time for reassembling the apparatus for pressing cheek plates 90 is reduced since all the components of the apparatus for pressing cheek plates 90 maintain an assembled state.

FIG. 8 schematically shows a state in which the apparatus for pressing cheek plates 90 of FIG. 2 is disassembled. A disassembling process of the apparatus for pressing cheek plates 90 of FIG. 8 follows that of the apparatus for pressing cheek plates 90 of FIG. 3.

If the piston 941 moves backward, the protruding portion 951 of the

jaw 96 is drawn out from the concave groove 911 of the bar 91 and is separated (refer to FIG. 7). Next, as shown in FIG. 8, after the rotating member 93 is rotated along a direction indicated by a curved arrow, the apparatus for pressing cheek plates 90 can be separated from the casing 24 by pulling the bar 91 out along a direction indicated by a straight arrow. In this case, since the cylinder 94 is combined with the rotating member 93, it rotates therewith. Since the apparatus for pressing cheek plates 90 can be easily disassembled by using the above-described method, maintenance time of the apparatus for manufacturing compacted iron 100 can be largely reduced.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

We Claim:

1. An apparatus for pressing cheek plates, the apparatus comprising: a bar that is configured to press a cheek plate installed at one end of a gap formed between a pair of rolls that compress direct reduced iron and manufacture compacted iron, to the gap; a piston that is configured to press and push the bar to the gap; and a cylinder that receives the piston, wherein the piston is configured to move along a direction in which the bar is extended by a pressure of an inner space of the cylinder.

2. The apparatus of Claim 1, wherein the inner space of the cylinder comprises first and second spaces, wherein the first and second spaces are separated from each other by the piston, and wherein the first space is closer to the bar than the second space.

3. The apparatus of Claim 2, wherein air enters into the second space and then presses the piston to the gap.

4. The apparatus of Claim 3, wherein the air in the first space is ventilated to the outside of the cylinder from the first space when the air enters into the second space.

5. The apparatus of Claim 2 further comprising: an air compressor that supplies an air to the second space; and a control valve that provides the air supplied from the air compressor to the second space and ventilates the air in the first space to the outside of the cylinder at the same time.

6. The apparatus of Claim 2, further comprising: an air compressor that supplies an air to the first space; and

a control valve that provides the air supplied from the air compressor with the first space and ventilates the air in the second space to outside of the cylinder at the same time.

7. The apparatus of Claim 1, further comprising: a supporting member through which the bar is penetrated, the supporting member supporting and fixing the bar; a rotating member that is hinge-combined with the supporting member based on an axis extended along a direction crossing a direction along which the bar is extended, the rotating member being provided with a penetrated opening through which the piston is penetrated; and a jaw that is located between the piston and one end of the bar, wherein the rotating member is located between the supporting member and the cylinder, and is fixed to combine with the cylinder.

8. The apparatus of Claim 7, further comprising a dust cover that is combined with the jaw and covers the jaw and the piston.

9. The apparatus of Claim 8, wherein a concave groove is formed at the one end of the bar, wherein the jaw comprises a protruding portion directing the concave groove and wherein the protruding portion is inserted into the concave groove.

10. The apparatus of Claim 9, further comprising a bolt that is inserted into a screw opening formed in the protruding portion and the screw groove formed in the piston, wherein the jaw and the piston are combined together by the bolt.

11. The apparatus of Claim 7, wherein the diameter of the penetrated opening is less than the diameter of the jaw.

12. An apparatus for manufacturing compacted iron, the

apparatus comprising: a pair of rolls that compress direct reduced iron and manufacture compacted iron; a cheek plate that is installed at one end of a gap formed between the pair of rolls; a casing that receives the pair of rolls and the cheek plate; and at least one apparatus for pressing cheek plates that is configured to be installed at an outer surface of the casing to press the cheek plate to the gap, wherein the apparatus for pressing cheek plates comprises a bar that is configured to press the cheek plate to the gap while penetrating the casing, a piston that is configured to press and push the bar to the gap, and a cylinder that receives the piston, and wherein the piston is configured to move along a direction in which the bar is extended by pressure of an inner space of the cylinder.

13. The apparatus of Claim 12, wherein the inner space of the cylinder comprises first and second spaces, wherein the first and second spaces are separated from each other by the piston, and wherein the first space is closer to the bar than the second space.

14. The apparatus of Claim 13, wherein air enters into the second space and then presses the piston to the gap.

15. The apparatus of Claim 14, wherein the air in the first space is ventilated to the outside of the cylinder from the first space when the air enters into the second space.

16. The apparatus of Claim 13, further comprising: an air compressor that supplies air to the second space; and a control valve that provides the air supplied from the air compressor

to the second space and ventilates the air in the first space to the outside of the cylinder at the same time.

17. The apparatus of Claim 16, wherein the at least one apparatus for pressing cheek plates comprises a plurality of apparatuses for pressing cheek plates, and wherein the number of control valves is one.

18. The apparatus of Claim 13, further comprising: an air compressor that supplies air to the first space; and a control valve that provides the air supplied from the air compressor to the first space and ventilates the air in the second space to the outside of the cylinder at the same time.

19. The apparatus of Claim 12, further comprising: a supporting member through which the bar is penetrated, the supporting member supporting and fixing the bar and being fixed on the outer surface of the casing; a rotating member that is hinge-combined with the supporting member based on an axis extended along as a direction crossing a direction in which the bar is extended, the rotating member having the piston penetrating therethrough; and a jaw that is located between the piston and the one end of the bar, wherein the rotating member is located between the supporting member and the cylinder, and is fixed to combine with the cylinder.