JP7101405B2 - Manufacturing method of obstacle nails and obstacle nails and gaming machines - Google Patents

Description

The present invention relates to a method for manufacturing obstacle nails and obstacle nails to be driven into a game board of a gaming machine such as a pachinko machine according to a predetermined arrangement, and a game machine in which the obstacle nails are driven into the game board.

Conventionally, in Patent Document 1, an obstacle nail having a head and a shaft portion as an obstacle nail to be driven into a game board of a gaming machine such as a pachinko machine according to a predetermined arrangement, and an intermediate portion of the shaft portion is inserted from the head portion. Obstacle nails with high hardness are described. This obstacle nail reduces the change in the repulsive force when the game ball collides with the obstacle nail, and can improve the durability of the obstacle nail while maintaining the game performance of the gaming machine.

Japanese Unexamined Patent Publication No. 2011-139783

However, the conventional obstacle nail described in Patent Document 1 is formed of brass even if the intermediate portion of the shaft portion has a high hardness, so that it is easily plastically deformed by receiving an external force. rice field. For this reason, with the conventional obstacle nails, the nails that intentionally bend the obstacle nails can be adjusted on the side of a game hall such as a pachinko parlor, and the winning probability can be adjusted. The pachinko machine with the adjusted winning probability is far from the winning probability set by the pachinko machine maker, and there is a problem that the planned game content cannot be reproduced.

The present invention has been made in view of the above points, and an object of the present invention is to provide an obstacle nail which is difficult to be plastically deformed and which is difficult to adjust the nail on the side of a game hall such as a pachinko parlor.

The obstacle nail according to the present invention is made of a steel material having a carbon content of 0.4 to 1.5%, and has an elastic limit stress of 0.5 to 1.4 kN / mm ² in a tensile test. And.

According to the obstacle nail of the present invention, the stress of the elastic limit is 0.5 to 1.4 kN / mm ² , and the plastic deformation does not occur even if the stress is less than the stress of the elastic limit. It can be difficult to adjust the nails with.

Here, in the obstacle nail, the stress of the tensile strength in the tensile test can be assumed to be 1.6 kN / mm ² or less.

According to this, it is more difficult to adjust the nails on the pachinko parlor or other amusement park side because the obstacle nail breaks when the amusement park side such as a pachinko parlor forcibly attempts plastic deformation. can.

Here, the method for manufacturing the obstacle nail is the method for manufacturing the obstacle nail, in which the first step of forming the steel material after wire drawing and annealing into a nail shape and the steel material formed into a nail shape are performed. It can include a second step of quenching.

According to this, since the steel material formed into the nail shape in the first step is quenched in the second step, the obstacle nail can increase the hardness of the steel material in the nail shape state. Therefore, the steel material forming the obstacle nail can be a steel material having a high elastic limit stress in the tensile test.

Further, in the method for manufacturing an obstacle nail, the quenching temperature can be 900 to 1200 ° C.

According to this, the hardness of the steel material forming the obstacle nail is preferably increased, and the stress of the elastic limit can be set to 0.5 to 1.4 kN / mm ² .

Here, in the gaming machine according to the present invention, it can be assumed that the obstacle nail is driven into the gaming board.

According to this, since the obstacle nail of the game machine is hard to be plastically deformed, it is difficult to adjust the nail of the game machine on the side of a game field such as a pachinko parlor.

According to the obstacle nail of the present invention, the stress of the elastic limit is 0.5 to 1.4 kN / mm ² , and the plastic deformation does not occur even if the stress is less than the stress of the elastic limit. It can be difficult to adjust the nails with.

It is a side view of the obstacle nail of embodiment of this invention. It is a figure which shows the stress-strain curve of the tensile test of the obstacle nail of the embodiment of this invention, and the conventional obstacle nail.

Hereinafter, the obstacle nail according to the embodiment of the present invention will be described. As shown in FIG. 1, the obstacle nail of the embodiment has a spiral head portion 3 having a round head shape formed at the rear end portion of the body portion 2, and a spiral spiral portion 5 driven into a game board on the tip end side of the body portion 2. Is formed. The head portion 3 and the spiral portion 5 are processed by the first step of forming into a nail shape in the nail making step described later. The length of the obstacle nail is 34 mm ± 0.5 mm, and the diameter of the body portion 2 is 1.8 mm ± 0.05 mm. When the obstacle nail is driven into the game board, the portion up to 15 mm from the tip of the obstacle nail is buried in the game board.

The obstacle nail has an elastic limit stress of 0.5 to 1.4 kN / mm ² in the tensile test so that the nail cannot be adjusted to bend the obstacle nail intentionally on the playground side such as a pachinko shop. It is difficult to adjust the nail because it does not undergo plastic deformation even if it receives a stress less than the stress of. If the stress of the elastic limit is less than 0.5 kN / mm ² , it may be possible to adjust the nail on the playground side. On the other hand, if the stress at the elastic limit exceeds 1.4 kN / mm ² , it will be difficult to manufacture as a steel material and it will be difficult to use it. More preferably, the stress at the elastic limit of the steel material is 0.8 to 1.2 kN / mm ² , and even more preferably 0.9 to 1.1 kN / mm ² .

The obstacle nail is formed of a steel material having a tensile strength stress of 1.6 kN / mm ² or less in a tensile test so that the obstacle nail breaks due to an excessive force and the nail cannot be adjusted. As a result, the obstacle nail will break if the nail is forcibly adjusted. When the stress of tensile strength exceeds 1.6 kN / mm ² , the steel material becomes too hard, and when the nail is forcibly adjusted on the game hall side, it is not the obstacle nail but the obstacle nail is driven into the game board. Damage such as cracks may occur. More preferably, the tensile strength is 1.55 kN / mm ² or less, and even more preferably 1.5 kN / mm ² or less.

Here, the elastic limit stress is the maximum stress that can be elastically deformed, and is the stress in the maximum elastic deformation region. That is, when a stress exceeding the elastic limit stress is applied, the obstacle nail is plastically deformed. From the time when the stress of the elastic limit is applied to the time when the stress of the tensile strength is applied, the steel material undergoes plastic deformation. The stress of tensile strength is the stress of the maximum tensile strength, and in the case of steel materials, the maximum tensile strength is shown immediately before the steel material breaks. The stress of the tensile strength becomes a value equal to or larger than the stress of the elastic limit. In the figure showing the stress-strain curve of the obstacle nail of the embodiment of the present invention and the conventional obstacle nail of FIG. 2, the elastic limit of the obstacle nail (example) and the conventional obstacle nail (comparative example) of the embodiment is shown. Ee and Ec are shown, and the tensile strengths of Examples and Comparative Examples are shown by Te and Tc. A stress of 0.5 kN / mm ² on an obstacle nail with a diameter of 1.8 mm is the same stress as a 130 kg weight hanging on an obstacle nail under the gravity of the earth. .. Since the game board to which the obstacle nails are fixed is made of wood or synthetic resin material that can be plastically deformed, the fulcrum is plastically deformed and cannot be determined. Therefore, the stress measurement was not based on the bending test, but on the tensile test (JIS G 3532 (iron wire): 2011 11.2 tensile test) in which a force is applied to the outside in the axial direction of the obstacle nail.

The steel material used for the obstacle nail should be hardened due to its carbon content of 0.4 to 1.5%, and should have a high elastic limit stress of 0.5 kN / mm ² or more. can. As a result, the steel material constituting the obstacle nail becomes a steel material that is not easily plastically deformed, and it is possible to make it difficult to adjust the nail on the playground side. If the carbon content of the steel material is less than 0.4%, the steel material may become soft and the stress at the elastic limit may be less than 0.5 kN / mm ² . On the other hand, if the carbon content exceeds 1.5%, the steel material becomes hard, and there is a possibility that the steel material cannot be deformed in the first step of forming into a nail shape. More preferably, the carbon content is 0.7 to 1.2%, and even more preferably 0.9 to 1.1%. The carbon content can be adjusted by selecting the steel material.

Further, the steel material used for the obstacle nail preferably has a chromium content of 10 to 20%. As a result, the obstacle nail can be made to have excellent wear resistance and can be prevented from being deformed due to wear. If the chromium content of the steel material is less than 10%, the wear resistance of the obstacle nail may not be sufficiently improved. On the other hand, if the chromium content exceeds 20%, chromium is an expensive raw material and may be uneconomical. More preferably, the chromium content of the steel material used for the obstacle nail is 12 to 17%.

Martensitic stainless steel can be used as the steel material used for the obstacle nail. Preferably, SUS440A, SUS440B, SUS440C and SUS440F can be used.

Next, a method for manufacturing an obstacle nail according to the embodiment will be described. The method for manufacturing an obstacle nail includes a first step of forming a nail-shaped steel material after wire drawing and annealing, and a second step of quenching the nail-shaped steel material. , Including.

As the steel material used for the obstacle nail, the steel material that has been drawn and annealed is used. The shape of the wire-drawn and annealed steel material is a rod-shaped body having a diameter of 1.8 mm ± 0.05 mm and a circular cross section.

As shown in FIG. 1, the steel material used for the obstacle nail is formed by crushing the rear end portion of the steel material to form the head 3 by the first step of forming the nail shape by the nail making process, and the spiral portion is formed on the tip side. 5 is formed.

The steel material used for the obstacle nail is subjected to a second step of quenching after the first step of forming the nail shape. The nail-shaped steel material is hardened to increase the hardness of the steel material in the nail-shaped state, and has a high elastic limit stress of 0.5 to 1.4 kN / mm ² . It can be made of steel. The quenching temperature is preferably 900 to 1200 ° C. If the quenching temperature is less than 900 ° C., it may not be possible to make the stress of the elastic limit high. On the other hand, if the quenching temperature exceeds 1200 ° C., excessive heat is applied to the steel material, which may be uneconomical. More preferably, the quenching temperature is 950 to 1100 ° C, and even more preferably 1000 to 1050 ° C. Further, the time for quenching the steel material is preferably 30 to 120 minutes. If the time for quenching the steel material is less than 30 minutes, the stress of the elastic limit may not be high. On the other hand, if the time for quenching the steel material exceeds 120 minutes, excessive heat is applied to the steel material, which may be uneconomical. More preferably, the time for quenching the steel material is 45 to 75 minutes.

After the steel material that has been subjected to the second step of quenching is cooled, it can be tempered as a third step. By tempering the hardened steel material, the steel material is imparted with tenacity and toughness, and the brittleness of the steel material can be reduced. The tempering temperature is preferably 150 to 300 ° C. If the tempering temperature is less than 150 ° C., the brittleness of the steel material may not be reduced. On the other hand, if the tempering temperature exceeds 300 ° C., excessive heat is applied to the steel material, which may be uneconomical. More preferably, it is 170 to 200 ° C. The time for tempering the steel material is preferably 60 to 180 minutes. If the tempering time is less than 60 minutes, the brittleness of the steel material may not be reduced. On the other hand, if the tempering time exceeds 180 minutes, excessive heat is applied to the steel material, which may be uneconomical. More preferably, the tempering time is 90 to 150 minutes.

For the obstacle nail as a steel material, the hardness of the surface of the steel material constituting the obstacle nail can be adjusted by adjusting the carbon content on the surface of the steel material. The carbon content on the surface of the steel material can be adjusted by carburizing to increase the carbon content of the steel material or decarburizing to reduce the carbon content, and either of them can be applied if necessary. The carburizing process increases the carbon content in the furnace at the time of quenching, thereby increasing the carbon content on the surface of the steel material and increasing the hardness of the surface of the steel material. The decarburization process reduces the carbon content on the surface of the steel material by increasing the amount of oxygen in the furnace during quenching, and lowers the hardness of the surface of the steel material.

The obstacle nails manufactured as described above are driven into the gaming board according to a predetermined arrangement, and when the gaming machine is used, the gaming ball collides with the obstacle nails and is repelled, improving the pachinko pachinko machine's palatability. ..

In the gaming machine into which the obstacle nail of the embodiment is driven, the stress of the elastic limit of the obstacle nail is 0.5 to 1.4 kN / mm ² even if the game is played for a long time, and the obstacle nail is hard to be plastically deformed. Therefore, it is not necessary to adjust the nails to return the faulty nails to the factory state. In addition, even if a person on the playground side intentionally adjusts the obstacle nail by applying an external force to the obstacle nail, the stress at the elastic limit of the obstacle nail is 0.5 to 1.4 kN / mm ² . , Obstacle nails are not easily plastically deformed and nails cannot be adjusted. On the other hand, when a person on the playground side applies an unreasonable external force to the obstacle nail and tries to adjust the nail, the stress of the tensile strength of the obstacle nail is 1.6 kN / mm ² or less, so the obstacle nail is easy. It breaks into. In addition, since the so-called plastic deformation range from the stress of the elastic limit to the stress of the tensile strength is narrow, it is difficult to adjust the force to the force in the plastic deformation range depending on the human force adjustment ability. It is extremely difficult to transform it.

Hereinafter, the present invention will be described in more detail by way of examples. In the examples, martensitic stainless steel SUS440C was used as the steel material for the obstacle nail. As a comparative example, brass (Cu65%, Zn35%) was used as the steel material of the conventional obstacle nail. The steel material of the obstacle nail of the example was wire-drawn and annealed, and was quenched at 1030 ° C. × 60 minutes and tempered at 180 ° C. × 120 minutes. The composition (%) of the steel material (SUS440C) of the example is shown in Table 1.

For the obstacle nails of Examples and Comparative Examples, the stress was measured by a tensile test, and the obstacle nails were actually driven into the game board to confirm whether or not the obstacle nails could be adjusted.

The tensile test was determined in accordance with the tensile test (JIS G 3532 (iron wire): 2011 11.2 Tensile test), but the test piece had a rod shape with a diameter of 1.8 mm and a length of 250 mm and a circular cross section. I used what is a body. The distance between the chucks was 190 mm. The stress-strain curve of the tensile test is shown in FIG. 2, and the stress and displacement (strain) of the maximum elastic deformation region (elastic limit) and the breaking point (maximum tensile strength) are shown in Table 2.

The stress of the elastic limit Ec of the comparative example (brass) is 0.27 kN / mm ² , whereas the stress of the elastic limit Ee of the example (SUS440C) is 0.98 kN / mm ² , and the elastic limit of the example. It was confirmed that Ee did not undergo plastic deformation even at a stress 3.7 times that of the comparative example. The state where the obstacle nail with a diameter of 1.8 mm is stressed at 0.27 kN / mm ² is the state where the stress is the same as when a weight of 69 kg is hung on the obstacle nail under gravity. The stress of 0.98 kN / mm ² on the 1.8 mm obstacle nail is the same stress as when a 255 kg weight is hung on the obstacle nail under gravity.

The displacement in the plastic deformation region is 12.0 mm in the comparative example (displacement from Ec to Tc) and 1.6 mm in the embodiment (displacement from Ee to Te), and the obstacle nail in the example has the plastic deformation region. narrow. Therefore, it is difficult to plastically deform the obstacle nail by adjusting the nail by hand.

The stress of the tensile strength Tc of the comparative example is 0.55 kN / mm ² , which is 2.07 times the stress of the elastic limit Ec of the comparative example (0.27 kN / mm ² ). The stress of the tensile strength Te of the examples is 1.45 kN / mm ² , which is 1.47 times the stress of the elastic limit Ee (0.98 kN / mm ² ). Therefore, it can be confirmed that the obstacle nail of the example breaks immediately when it receives a stress exceeding the maximum stress in the elastic deformation region, as compared with the obstacle nail of the comparative example. In both the examples and the comparative examples, fracture was confirmed immediately after the stresses of the maximum tensile strengths Te and Tc were shown.

To confirm whether or not the obstacle nail can be adjusted, the obstacle nail was driven into the game board so that the driving size was 15 mm, and the obstacle nail was hit with a mallet to confirm whether or not the adjustment was possible. The size of the obstruction nail is the size of the obstruction nail that is generally distributed (length: 34 mm, body diameter: 1.8 mm, head diameter: 3 mm), and as shown in FIG. 1, spirals toward the tip side. The one provided with the spiral portion 5 formed in a shape was used. The obstacle nail in the comparative example was easily plastically deformed by hitting it with a mallet, and the nail adjustment was easy. On the other hand, the obstacle nail of the example did not plastically deform even when hit with a mallet, and it was impossible to adjust the nail. Further, when an adjustment was attempted with a large mallet as a trial, the obstacle nail of the example was broken (broken) before being plastically deformed.

(Modification example)
The obstacle nail of the embodiment can be implemented even in the following embodiments.

The obstacle nail of the embodiment is provided with a spiral portion 5 formed in a spiral shape on the tip end side, but a configuration in which the spiral portion 5 is not provided may be provided.

As the steel material used for the obstacle nail of the embodiment, a wire material that has been drawn and annealed is used, but a steel material sintered by MIM (Metal Injection Molding Method) can also be used. ..

In the obstacle nail of the embodiment, the wire wire which has been drawn and annealed is provided with the head 3 and the spiral portion 5 by the nail making process, but the block of the steel material is carved and hardened. Can also be manufactured by.

Although the obstacle nail of the embodiment is used as an obstacle nail for guiding a game ball, it can also be applied to a nail or the like which is a shaft of a wind turbine.

2 ... Body, 3 ... Head, 5 ... Spiral, Ee, Ec ... Elastic limit, Te, Tc ... Tensile strength.

Claims (5)

Obstacle nails made of steel with a carbon content of 0.4-1.5% and characterized by an elastic limit stress of 0.5-1.4 kN / mm ² in a tensile test. The obstacle nail according to claim 1, wherein the stress of the tensile strength in the tensile test is 1.6 kN / mm ² or less. The method for manufacturing an obstacle nail according to claim 1 or 2, wherein the steel material after wire drawing and annealing is formed into a nail shape, and the steel material is hardened into the nail shape. A method for manufacturing an obstacle nail, which comprises a second step. The method for manufacturing an obstacle nail according to claim 3, wherein the quenching temperature is 900 to 1200 ° C. A gaming machine characterized in that the obstacle nail according to claim 1 or 2 is driven into a gaming board.

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