Our company is a manufacturer of gear, processing gear from lathe turning to heat treatment process. The root of this technology, which has accumulated since its establishment in 1931, and by using all of these technologies, we have obtained the trust of our customers in various fields. Before start working, we constantly striving as follows:



この石碑は本社玄関にあり、このような文字が刻まれています。「送迎に 笑を浮かべた 草を木を 愛し育て 心の友に 社長」「草を木を愛する気持ちと、同じくらいの気持ちで歯車づくりをして欲しい」社長はそんな気持ちで仕事に臨んで欲しいのかもしれません。

歯車づくりの「奥義」とは 奥義その一 歯車づくりの「奥義」とは 奥義その一

 At first, we buy round steel and forging steel, then cut them into the size as requestment, and put them into the next step. In this step, we decide the basic materials, and continue processing until finish as drawings, in some cases, material must be chosen to suit application. This is rarely case, so be careful in choosing. In addition, according to materials, in order to reduce the amount of distortion or change weight during heat treatment process, it may require a multi-step called " Thermal refining " to equalize the different molecules of the material. This is a work that requires "experience and intuition", too.

歯車づくりの「奥義」とは 奥義その二 歯車づくりの「奥義」とは 奥義その二

 In turning processing step, we use lathe machine and milling machine to cut round steel and forging steel, and of course these machines also being used in cutting gear. Further, after the heat treatment process, dimension shall be changed, so this should be considered, too. Moreover, in cutting gear and engraving mark step, cutting gear is the step need to be made attention most, in processing gear, the biggest problem is the indentation on gear surface, so in order to prevent this matter and make gear to be sharpen, it need to process sharp gear surface “Semi-topping hobbing” or “Semi-topping pinion cutter” in the same time with cutting gear. Because if gear have any indentation, it shall be non-usable product, so it should be make attention to pack and transport step.

歯車づくりの「奥義」とは 奥義その三 歯車づくりの「奥義」とは 奥義その三

 After processing all gear surfaces, gear shaving step is the last processing step. Due to this shaving process, we could adjust dimension of gear with high accuracy. In order to process dimension of gear surface near the required dimension, it is necessary to give the precise specification. Of course, we also think careful about dimension being changed after heat treatment process. For the 3rd Parties, this shall be boring works. Due to this shaving process, we could make decision about the gear surface, teeth of gear is the same or not, then we could know the using time of gear. Besides that, before shaving gear, in some cases, we have to sharpen gear surface, this step is considered as a step make gears match to each other.

歯車づくりの「奥義」とは 奥義その四 歯車づくりの「奥義」とは 奥義その四

 As I mentioned as above, most of the gear is subjected to heat treatment process to be shipped. It could increase the hardness, but if over temperature, gear shall be broken easily, otherwise, not enough temperature, the hardness shall be not enough. By microscope, through molecule inspecting data, heat treatment process shall be done carefully after inspection of heat treatment process gear sample. After heat treatment process, dimension of products shall be changed, so it could be calculate carefully for this changement during processing. About heat treatment process, there are many methods, for example: carburizing hardening and tempering, fire, gas nitriding, induction hardening, … According the type of material and usage purpose, we could choose the processing method. For example: It needs about 900℃ and 8 hours for carburizing hardening. For tempering, it needs about 300℃ and 2 hours. This is a work require experience and high technique level.

歯車づくりの「奥義」とは 奥義その五 歯車づくりの「奥義」とは 奥義その五

 Gear surface dimension and shape is decided after shaving processing step. However, if you consider about turning of gear, it also has another important factors for example: offset prevention during turning, it needs to be processed outside diameter and inside diameter. In order to make such as processing, using grindstone with high speed. It seems so simple, but it shall make increase the accuracy of gear transmission. The accuracy of this processing is up to micro. Up to this step, it is nearly to finish processing gear.

歯車づくりの「奥義」とは 奥義その六 歯車づくりの「奥義」とは 奥義その六

 After these above steps, at last is the inspection step before finishing. We shall use the newly gear inspecting machine to check again the uniformity of gear surface and teeth, consider that incorrectness is in tolerance or not. Of course, we also check again the dimension of each gear. Up to this step, if everything is correct, we shall export products. However, besides gear axis, we also inspect the articulation between gears, gear axis. If waste products still could be fixed, we should sharpen gear and teeth of gear before finish. But if it couldn’t be fixed, everything shall be nothing. This is not in gear processing, but it is considered as the dangerous in processing work, right ? Above is the simple explaination about processing gear, but may be you could understand a little about this work? We are so happy to give you the other think about processing gear, a necessary products in normal life.