David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
Table of content Thanks ........................................................................................................................................ 3 I°) Presentation of Samick Sports .............................................................................................. 4 A°) A little bit about the history of Samick Sports ................................................................ 4 B°) About Samick Sport......................................................................................................... 4 C°) Samick’s products............................................................................................................ 6 II°) My Work into Samick’s Sports ........................................................................................... 7 A°) Introduction ..................................................................................................................... 7 B°) Contacts with French Customers ..................................................................................... 8 C°) Designing a new Sander machine.................................................................................... 8 1°) Definition of the work .................................................................................................. 8 2°) How I organised my work ............................................................................................ 9 3°) Definition of the main shaft motor and ball bearing .................................................. 11 4°) Designing the High part with the pneumatic cylinder................................................ 12 5°) The Horizontal table....................................................................................................... 13 6°) the vertical Table ........................................................................................................ 13 7°) the different Draw ...................................................................................................... 14 D°) Designing a sanding belt machine................................................................................. 14 1°) Definition Of the work ............................................................................................... 14 2°) the system of roller ..................................................................................................... 15 3°) How to adjust the position of the roller? .................................................................... 16 4°) How to simplify the system to lock the two positions?.............................................. 16 E°) the second Sanding Belt Machine................................................................................. 17 1°) Definition of the work ................................................................................................ 17 2°) the base of the machine .............................................................................................. 18 3°) the system to adjust the Second guide........................................................................ 18 4°) the tables..................................................................................................................... 19 F°) the Stringing Machine .................................................................................................... 21 1°) Definition of the work ................................................................................................ 22 2°) the new system to string the limbs ............................................................................. 22 3°) the fixer....................................................................................................................... 23 G°) the automatic sawing machine....................................................................................... 24 1°) Definition of the work .................................................................................................... 24 2°) the principle of the machine ........................................................................................... 24 3°) How to easily make this machine automatic? ................................................................ 26 H°) Producing....................................................................................................................... 26 III°) what I learned with Samick Sports................................................................................... 27
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
Thanks
I would like to thank M Bong J Lee, president of Samick sports, for this great training. It was a really extraordinary experience to work in a so prestigious company, known all over the world for the quality of its products, and the talent of its archers. I have always wanted to work into a such company, in a domain that I know as a passionate archer. He gave me this chance, and I hope he enjoyed my work and my motivation all along my stay in his company. I would like to thank M Cha too, without who this training would be impossible. He was the one in Samick Sports speaking English. He was the first contact I had by Internet to find this training, and he was the one who helped me to come to Korea. In all moment of my training, he was behind me to assure my security, and also my comfort and my good health. I think I would be allowed to contact him often in the future. M Kim was the one who took care of me during the time I wasn’t at work. He lived in the same dormitory as me, and brought me all his help. On sunday, he was a great guide, and made me visit and discover Korea, a so beautiful country. This help really contributed for me to enjoy my training.
Many thanks to my teacher M Alexandru SAVA, for all the interest he had for my work. I know it wasn’t easy to take care of a student when he is at 10 000 Km of distance, but he managed to do it very well. He provided me some really useful advices. I would like to say how grateful I am to the president of jury, who give me a little bit of his precious time, to listen to my work. I guess he is really busy, but he found some time for me. Thank you to my mother and my sister, who sent me Email and brought me the support for a such experience. Sometimes I missed my country, and they were here. Finally, I would like to thank all the people of Samick sports for their support and help. Everybody took care of me, and made me feel at home in Samick Sports factory. I don’t speak Korean, but the communication was not so hard with them.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
I°) Presentation of Samick Sports
A°) A little bit about the history of Samick Sports 04 1975: foundation of a department of archery in the Samick Piano factory. 07 1977: Beginning of exportation to France and some others countries. 05 1985 : Beginning of production of “Progress 1” and “Progress 2”, most popular bow for beginner and intermediate archers. 04 1991: Became officially “Samick Sports Co ltd” 07 1992: Nominated by Korean authorities as the best company for Sports Equipment 04 1995: Beginning of the production of the “Agulla” 07 1999: Beginning of the production of “Ultra”, one of the greatest models of Samick for top archers. 09 2000: Olympic Games of Sydney. The team of Samick’s archers was the winner in individual games (both male and Women) and by team (Both Male and women), all with Agulla Bow.
B°) About Samick Sport Samick sports is located in the City of Kimpo, a small city at about 40 Km from Seoul, the main City of this country. There are about 30 persons working into this company. The factory is open from Monday to Saturday, from 8:00 am to 20:00 pm. Samick Sports is one of the main manufacturers of bow in the world. This company export its bow into more than 50 countries all around the world. For Samick sports is France the place in Europe where they sell the most of bows. And they want to develop the commercial links with this country. By order of importance, the archery market is located in USA, Europe, and Asia. Europe is a quite important market The main customers in Europe of Samick Sports are LAS and SSA. SSA is a Belgium company, really important on the sport market in Europe. They resale the Samick bow all over Europe. A concurrent of SSA is LAS, based in Nederland. France is one of the European countries where archery is the more developed. It’s really important for Samick Sports to have good relationship with European sports companies.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
As a bow manufacturer, they are sponsoring a lot of famous great archers. Most of them are from Korea. This people like Kim soo yong, medalled in Sydney Olympic games 2000, or Chang Young Ho, world champion of 97. They are the sponsors too of some young and talented archers, who show some aptitudes and talents in junior competitions. During the Olympic games of Sydney, 2000, the 6 best archers owned to the great family of Samick‘s Archers. These archers help Samick to be the best, by testing the new models and giving advices to improve quality. Samick is now known as the more famous bow manufacturer of the world. It’s a quite normal think, when you know that Korea is said to be the land of archery. Their main concurrent are Hoyt USA, an American brand really expensive and really famous in archery world, and Win&win, a Korean Brand, growing really fast (they bought the old factory of Yamaha, in Japan and doubled their capacities of production this year). Archery market is dynamic, and Samick has to work hard to stay the best manufacturer. At the beginning of 2003, Samick Sports will open a great factory in China. This factory will be as big as the one in Korea. It won’t produce the same bows as Samick, but cheaper ones. The quality of these bows will be inferior of the quality of Samick’s bows. This would be for beginners and will be cheaper than actual products. That’s why they decided to create a new name for these bows. At the moment I wrote this word, they had not decided of the name. I was allowed to visit the new factory in China, but this factory is not opened now. Samick Sports is in a constant evolution. They just moved to a new factory (in Korea), with more space to create the new bow. Samick‘s team is growing every day. The government of Korea discerned them the price of the prominent company of Korea many times. They are one of the greatest bow manufacturers of the world, but they want to become the greatest one. By this way, the new Korean factory is quite big. The factory is located on the ground floor, and the administration on the first floor. On the first floor, there is too a flat, where I lived the 3 latest months. When I arrived the factory was new, and this flat wasn’t finished. They are diffusing a lot of advertisement in all the specialized press. In France, they use the newspaper of the French Federation of Archery (FFTA) to promote their goods.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
C°) Samick’s products The products of Samick Sports are really various. They make bows for beginner to top archers. And there are different kind of bows, all manufactured by Samick Sports. Samick Sports products Recurves Bows, Hunting Bows, Traditional bows and beginner bows. They are all described in detail on the web Site www.samicksports.com . The main products of Samick Sports are recurved Bows and hunting bows. The recurves bow are said Take Down, because they consist of 2 main parts: The Handles and the limbs. They are called “classical bows” too. Handles are made in Magnesium or Aluminium. These are some products as “Progress I and II”, or the Master, by example In 2002, Samick Sports added some new products to the catalogue, like the Master, or the Mizar. This new product are made to allowed Samick Sports to stay on the first step of archery. They manufacture some wooden bows too, as the jazz, for people who want performance but natural materials. They manufacture some long bows, which is a kind of mono-bloc bows, in wood. This is some traditional bow, like the old one you can see in movies. These bow are mainly used by hunters. It’s by example the SLB. That kind of bows doesn’t used things like sight, stabilizers. It’s the strict minimum in archery, to keep traditions. For beginners they make some special bows, adapted with low draw weight. This is the mind series. That kind of bows have some adapted price too. And the latest kind of bow is the traditional Korean Bow. These bows are very short and can be handling by right or left hand. It’s by example the SKB. The web site of Samick Sports presents some others products as sight or target. They aren’t made into Samick Factory but buy by Samick Sports and resold.
A skb, traditional Korean Bow.
The Agulla ultra handle
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
II°) My Work into Samick’s Sports A°) Introduction As a trainee, Samick Sports provided me a room into a dormitory. The first month, I shared a flat with a Chinese girl and the mother of M Bong J. Lee, president of Samick Sports. Ms Bong is the one who created the company. She is the owner of the place too. This dormitory was at 5 minutes walking from the factory. I lived the rest of the time in a new dormitory into Samick Sports factory. It was really great to live so close of my working place. Every day, lunch was provided by the company. And during the week, many diners were provided by the company too. I began to work every day at about 8:00 am. Lunch was at 12:30 am, and dinner at 5:10 pm. The end of the working day depended of the day. In general, we stopped working at about 19h00. During my stay into the company, I had the opportunity to get participate at different stages of activity, from the design of machines to the production and customers relation.. My different assignments were : -
designing 6 new machines (main job) Participate at the production Having contact with French customers Translating the homepage into French
My activities were really large, and I wasn’t affected in a particular department. It allowed me to discover all the parts of this company. In this paper, I will try to explain what I did during the different assignments. When I arrived, I was really proud to join to a so great company. Even if nobody spoke English, except of my responsible M Cha, I was quite confident. But later, I sometime missed my country. I think every abroad trainee gives that kind of feeling (and that was confirmed by my E-mail’s friend). But it was really occasionally, and I really enjoyed my trainee. I learned many things during my stay. Korea is a really beautiful country, and Samick Sports will always be for me the number one on archery market.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
B°) Contacts with French Customers During my stay, I was able to be a privileged contact for French company. It was easier for them to speak French with me, to make me understand their wishes. I had the chance to talk to important people, (from by example) the French federation of archery (FFTA). I learned how to have some professional contacts with customers. It was one of the first things I did when I was into Korea. I was able to help Samick sports and some customers too. It allowed me to have some important contacts, maybe useful for my future professional life, as an engineer. I was in contact by example with Ms Laurence Frere, the responsible for communication of the French Federation of archery. I had some talks with the president of SSA, the greatest company in Europe selling Samick bows and others brands of bows. He’s from Belgium and was pleased to find somebody speaking French here (even if he speaks very good English). One day he went to Samick Sports during a business trip, and we were both pleased to speak French, and about archery. I discovered that speaking in the native language of a customer can made the relationship easier. It was a work all over my training.
C°) Designing a new Sander machine 1°) Definition of the work The second mission I had to do was to design a new sander machine in order to replace an old one. There isn’t any developing department for machine in Samick Sport. Only a fixing department. And people of this department were too busy to design this machine. So this project was given to me. This machine was used to prepare a special layer of wood placed into the limbs, the parts in bows that are bending. It was really important to respect the dimensions of these pieces of wood. The machine had to sand the wood by a come and back movement. Then it allows to work with 4 pieces of wood each time. With that capacity the production rate will be increased. On the following picture called picture 1, you can see the old sanding machine, that I had to replace.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
Picture 1 : the old sanding machine
2°) How I organised my work At the beginning I tried to imagine a new concept of sanding machine, with a moving head, but it wasn’t the wish of Samick Sports. The thing I had to do was to design a machine with a mix of the different solutions existing which I could find in the factory, on other machines. I had many discussions with an engineer from Samick Sports, explaining me what he expected for this machine. We chose to keep the system of moving table. It was easy to design with an infinite screw. For the paper, we chose to move the head of the machine up and down with the same system. By this way, the table and the head would be locked when the machine is turned off. Nobody can be hurt. I drew a three dimensions model with the CAD software Pro-Engineer, from PTC. It was software well known, because I learned it at school. By this way I was able to concentrate on the design of the new sanding machine, instead of learning new software. I think this assignment allowed me to learn a lot of things on solution I didn’t know in construction.
I used the help of Internet to find all the documentations I need. By example, I had to find the normalized dimensions of ball bearing, and such elements like pulley and linear guide. I tried to find these elements which were already designed in such web sites like www.Traceparts.com , or www.Web2CAD.com, But they used a file format not acceptable by Pro/Engineer. But on these two web sites, I found most of the dimensions I needed. I had to redraw by myself all the normalized elements. I used the web site www.tec.nsk.com to find the dynamical characteristics of the ball bearing. But I found some elements, like the big screw, on the website www.centralproe.com . It was one of the longest things to do.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
I found the system to move the table on the website of Rexnorth, a company of Bosch. I chose some runners, in function of the dynamical charge on it. On the site, there were STEP files, than I could import in Pro/Engineer.
I worked about 6 weeks on the mechanical conception. The most difficult thing for me was to define the motors. I worked a lot of time to find a mathematic model to calculate the different efforts while working.
On the next page, you can see the picture of the new sanding machine (picture 2). This is a 3 dimensions view from Pro/Engineer.
Picture 2 : General view of the new Sanding machine
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
3°) Definition of the main shaft motor and ball bearing The main motor, used to sand the wood, was the most difficult one to choose. Because the power depended the quantity of wood sanding, I knew that I was able to choose any motors, but a too small one will reduce the capacity of the machine, and a too big one will cost too much money. To dimension this motor, I found this solution. The table was moving due to the screw. The couple of the screw was known when I chose the motor of this screw. This motor was easy to determinate with the speed in work, and I choose the max torque transmitted to the screw: 20 Nm. It was quite the same as another sanding machine, in the factory. With that information, I was allowed to calculate the maximum horizontal force of the Table (and then the wood) on the main cylinder. This force was given by the diameter of the screw and the maximal torque. With a coefficient of friction approximated of 0.5, in worst conditions, I determined the vertical force of the cylinder on the wood. I had the vertical and horizontal forces, so I was allowed to determine the power of the motor. But with this power the motor would stop the rotation of the shaft. So I decided to choose a motor twice more powerful that this value. The choice of the coefficient of security (2) was a personal choice. I thought it was a good choice. With this information, I was allowed to check the ball bearing on the main shaft. In a such small place, and due to the conception, I could put only one ball bearing. So I decided to choose a double ball bearing with angular contact. I found all the dimensions on the trace parts web site. It’s a ball bearing made by SNR, a French brand. The calculus said me it will work without any problem during about 8 years, 11 hours a days, 6 days a week. I knew that the machine would not work a so long time every day, but I would like to maximize the lifetime, and due to the mistake of the calculus it was a quite good approximation.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
4°) Designing the High part with the pneumatic cylinder
This part was made to guide the sanding paper. The pneumatic cylinder is here to make the change of the paper easier. When you need to change the paper, stop the air pressure. The cylinder axis will go down, and the tension in the paper stopped. The cylinder is a Rexnorth one, a brand own by the great group Bosch, a symbol of quality. I take a cylinder which can also guide the whole element in translation. Here is the view of the system : First of all I found an approximation of the weight of the whole part. With the software, and some approximations, I estimated than in the worse case it would be 15 Kg (all in Steel, estimation made with Pro/engineer ). Picture 3 : roller, detailed view
So I chose a Cylinder able to have a force a little bit more important, to give a tension to the paper. If the weight of the system is less important, we would be able to add a system to reduce the pressure with a pneumatic system. But the pressure can only be decrease, and not increase. The air pressure in the factory was of 8 kgf, something like 0.8 Mpa. So with a diameter of 20 mm, the cylinder will give a tension of about 100 N in the paper. With this tension, I was able to calculate the ball bearing life time. This ball bearing had no axis charge, and the only charge was the weight and the 100N tension. With this calculus, I determined that this ball bearing (simple row by SNR) will work a really long time (more than 30 Years…)
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
5°) The Horizontal table To make the horizontal table moving, I chose a system with a screw and a nut. It would be easy to fix the speed of the table with the pitch of the screw (4mm). With a so small pitch compared to the diameter (22 mm), the screw would be not reversible, giving safety to user. The table can not move without the movement of the motor, and would be locked. To guide the table, I chose some rail and runner, by Rexnorth again. This system is really small and miniaturised. Even if it’s really small, it can support a quite high load, like 6000 N each. There were 4 runners under the table, and compared to the load calculated on the first part, it was really sufficient. Picture 4 : The moving table system
On the picture 4 (previous page) you can see the table in red, the runners and rails in grey, the screw in blue and the nut in green. This view is from the bottom of the machine.
6°) the vertical Table
For the vertical movement, I used a screw and nut system, the same as the horizontal one. Because of the axis load on the ball bearing of a such mechanism, I chose a double row ball bearing, with angular contact. I tried to use the same as the one used for the main shaft. After checking by calculus, it worked. This shaft will be turned by a motor. A great reduction between the screw and the motor will allow 2 things: The speed of this table will be very slow and allow a good precision needed in this work. The high torque obtained will fight the weight of the mechanism and will move the system. Picture 5 : how the vertical table is linked to the machine base.
On the picture 5, you can see the screw used to move the vertical table. The screw has a small pitch, and is not reversible. It allowed me to not use a system of break to stop the position.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
7°) the different Draw As this machine would be build by an external company, I decided to save every draw (28 different pieces and some general views) in a universal file format, the DXF. When I looked after some normalized elements, I realized that it was the file format the more present on Internet. It’s a file format used by Pro/Engineer, AutoCAD, Solid Works… All the main CAD software used it. It was really easy to choose this file format. I chose not to draw the different motors, because I wasn’t able to find some 60 Hz motor on Internet. I joined an Excel File on the CD, giving the different characteristics of the motors. After choosing the motors, the company will have to had the fixation whole. I didn’t draw them because it depends of the motors. I tried to have some real size draws, and adjusted the size of the draw. But sometimes it was impossible, because of the size of the components.
D°) Designing a sanding belt machine 1°) Definition of the work This second main assignment took about 6 days to be finished. It was really faster than the first one, for many reasons. First of all, this machine was really easier to design than the first one. And the other think was that I had already the different information I need like where to find the ball bearing characteristics… A great part of my first assignment was to find every information and to be accustomed with the software. So I had to begin to design three new belt sanding machines by this one. It was a quite simple one: 3 rollers are used to guide the paper. One is quite big to sand big surfaces, the other one is small, to be used in part with small radius.
Picture 6 : The old belt sanding Machine 1
As you can se on the picture 6, this machine is really old. So they decided to give me this assignment.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
The main thing I had to change here was the size of the vertical rollers. According to the technician, it had to be higher to use a larger paper. I tried to make the design as simple as I was allowed to do. I split my study in 4 different parts: the 2 first parts were to design the system of rollers, with the ball bearing. Another part was to study the way to link the adjustable roller (in front on the picture, moved to change the paper). The next part was to know how to adjust the position of the adjustable roller. Latest point was to find how to simplify the system to lock or unlock the moveable part.
2°) the system of roller I designed the 2 systems of rollers in the same principle: 2 independent units add to the machine. Then it would be easy to mount, and easy to change or to maintain in function. The main charges on the ball bearing were axial, and not radials, that’s why I decided to use some angular contacts ball bearing. Because of the potential weight of the shaft, I chose double row ball bearing for the bigger subsystem, and simple row in the smallest one. I found all about them on the homepage of NSK at www.tec.nsk.com. Unfortunately there wasn’t any Pro/Engineer Files, so I had to do a small draw of the ball bearing. I did the calculus to check than this ball bearing will work during years. This calculus gave me a lifetime of around 22 years. Of course it’s just a statistic calculus, and there is certainly some mistake in the approximations of some forces, but I tried to do this calculus in the worst conditions.
Picture 7 : detailed view of the subsystem roller
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
This is a quite classical conception. The top ball bearing is locked with a cover, not drawn here because there is the machine base between the cover and the system. This allows the cover to lock the subsystem on the base, to centre it and to lock the ball bearing. The wedge in the down part is used to link a pulley. This is the part linked to the motor. This kind of conception is used for the 3 rollers.
3°) How to adjust the position of the roller? On the old machine, there was a mechanism I had to conserve, but to improve too. The angle between the roller and the vertical was variable, to be adjusted to the paper. The old mechanism was composed with a screw, but was a little bit unconventional. I decided to keep the principle of a screw, and to make this system more acceptable. So after some different tries, I decided to fix the shaft in the articulation of the roller system. By turning a nut, you are able to move in the two direction of the screw. A spring is here to maintain the system in place. We can see on this picture 8 a three dimension view of the system. For the comprehension of the view, there is no machine base.
Picture 8 : The positioning mechanism
4°) How to simplify the system to lock the two positions?
To choose the position of the adjustable roller, I chose to simplify the existing system. It was a mix of spring and shaft, using a really complicated Cinematic. I Kept the spring (not drawn on the picture bellow) to assure the tension of the paper. This spring is fixed on the main Toggle.
I made a part to attach the last toggle when you want to change the paper. This system is safe and simple, I think. The 2 positions are stables. You can see this system on the next page, picture 9.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
Picture 9 : The general view of the belt sanding Machine
E°) the second Sanding Belt Machine 1°) Definition of the work This machine was used to sand long bow. The configuration of the machine was quite the same than the previous one, but with only 2 rollers to guide the paper. The tension of the paper is given by a pneumatic cylinder, which allows to easily change the piece of paper. I had to add to the new machine a system of table that we can easily put out and put on. This machine will be used for the longbow, and the operator needs a great table to work. So the work I had to do was to add the table, and to improve the system to adjust the position of the second cylinder. This system was quite curious, as I will explain later.
Picture 10 : General View of the sanding belt machine 2
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
2°) the base of the machine
I used my previous work for this machine. I used the same system of shaft with pulley and roller bearing to link to the motor. I had just to add another ball bearing on the shaft, which is used as a guide for support where the piece to sand is fixed. I keep the same diameter for the roller and this ball bearing than the old machine. By this way, there will be no need to change the different supports (adjusted to the machine). I mounted the second shaft on a cylinder, to allow the paper to be changed easily and safely.
3°) the system to adjust the Second guide On this machine, we need to adjust the position of the roller. The solution used on the old machine was “exotic”, in the sense that it would not work. It was hyper- Static. And it played with the deformation of the screw. It was for me a thing to improve. Finally, I found a solution iso- static. It uses a screw, guiding a small shaft. This shaft is in a groove on the shaft. The all system turn and is allowed to adjust the tension of the paper. It looks like this:
Picture 11: The system to adjust the second guide
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
The spring is here to push the system. A nut is used to compress this spring. And the whole roller turns. The system is attached to a special pneumatic cylinder, that can’t turn. Inside the roller, there is some ball bearing to guide the rotation of this one. And with this solution there is one more positive things : you protect the paper. If there is a too high pressure, the spring is compressed and the roller move.
4°) the tables The tables on the side were a real problem for me. I spent a lot of time, trying to thing how to lock and unlock them. Finally I decided to use a system of clip. 2 small shafts are put into some wholes to block the rotation of the table. The position of this Shaft is assured by two springs. When somebody wants to use or not the tables, he has only to pull the 2 shaft, and to put the table in position. These 2 Shafts have a sufficient section to resist to the charge. A long bow is not really heavy. This is a view of the system:
Picture 12 : main locker system
You can see on the picture 12 the locker system, using the spring. A nut (in violet) is used to lock the system on the base. Because this system was insufficient, I had a support to the table. The torque, depended of the weight of the longbow would break the locker system without this support. I used the same kind of locker to attach the support. So the support can be easily put out. When you want to use the side table, you have to lock the first system, and then to put the support. On the next page, you can see the picture 13, which is the view of the second locker system. The first on is to place the position of the table, the second one is used to support the weight of the system during the work.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
Picture 13 : the second system of locker
F°)The third Sanding Belt Machine 1°)Definition of my work This machine was quite the same as the previous one. The difference between this two machines were that on this one, there was no need to add some side tables. This machine is used to sand some small pieces of wood, and to create some angles. A fix support was on the old machine, used too to sand the part. But the immobility of this part was not good for the machine, because only one small part was working. To improve the lifetime of this machine, engineers asked me to design a new machine, with a movable part. 2°) The Movable part To make the support movable, I used the same runners as the other machines. Then I had to find a solution to stop the movement during the work on the wood. So I used the same quick fixing system than the one used to fix the table on the previous machine. By this way it’s really easy to move and lock the part. A guide with some whole is put at the on the machine base. The quick fixing system is fixed on the moveable part. The cylinder of this system come into a whole from the guide, and then fix the movable part. You can see a general view of the machine on the picture 12 next page. I won’t write about the other part of the machine, because I used exactly the same thing than in the previous machine. It would be more easy to build and less complicated to repair if there was a problem one day.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
The picture 14 is a general view of this machine. As you can see, this machine is quite the same as the previous one.
Picture 14 : general view of the sanding belt machine 3
On the following picture, number 15, you can see the mechanism in a more precise way. The spring id here to maintain the position of the fixer. The violet part is here to allowed the system to be well handled.
Picture 15 : detailed view of the fixer system
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
F°) the Stringing Machine 1°) Definition of the work The fifth machine I had to design was a stringing machine, which allowed making some sign on the limb, in order to finalize it. There was a machine doing this, but engineers from Samick would like to improve it. So they asked me to make some change. This system is used to bend the limb, as if it was mounted on a bow, to pace a string and check the alignment of the limb. Then the operator write a sign on the limb to finalize the work later on another machine. The engineers here were asking me to improve the security of the machine by rethinking the design of it. They was expecting a machine which allowed the worker to be far from the limb, in case it would break. If the limb break during this process (due to a default of fabrication), the worker could be injured. On the picture 16, you can see the old machine, used in the factory. The limb is bending by a cylinder. When the cylinder is in the high position, the operator put the string on the limb. It was not as safe way to proceed.
Picture 16 : the stringing machine
As you can see in the previous picture, the system used to string the limb was composed of a fixer, where was fixed the limb, a cylinder, bending the limb, and a string. With that system, the operator had to place the limb in tension, and he could be hurt.
2°) the new system to string the limbs For the new system, I tried to find a way to string the limb with the minimum of danger for the operator. I found a solution where the string was attached to the bow before to put into tension. The string is attached to a shaft, and this shaft is movable. A cylinder, from Bosch Rexnorth moves this part. As the limbs are quite different, depending of the model of bow, the string had to have a variable height. The shaft can be put up or down, and is fixed by a system of 2 pressure screws.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
Picture 17 : The stringing system
I chose a cylinder with a great course, and then the length of the string will be the parameter to change the tension of the limbs. This cylinder has two guide, which don’t allowed the system to rotate. By this way the movement would be only translation. As other part on others machines, it’s a normalized part form Rexnorth. The system to fix the string on the shaft was to redesign too. A nut and screw was used to fix it, but I thought it wasn’t a safe system. So I chose to make the shaft conic at the extremity. With a nut, people will be able to introduce a force on the string, and she will be fixed only by friction, and then easy to adjust.
3°) the fixer At the ask of people using it, I change the way to fix the limb. The limb was fixed with a system with a shaft put into a hole, and maintain in contact with a special part. According that the different limbs have different thickness, this special part had to be change for each kind of limbs. That was not really practical, and need some time to change. I decided to put a mobile part, moved by a screw. Then with this mobile part, the whole fixer can be adjusted to the limb. No need for a special part for every Limb. I also add a system of rulers, then people can have the indication of the different parameters for each limb, and they will be no need to adjust the fixer each time. The parameters you can adjust with this system are the high, the angle, and the horizontal position. This system will fit to every kind of limbs, even futures ones.
On the next page you can see the fixer system (picture 18).
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
Picture 18 : The fixer system
I used some runner to allow the system to move from left to right. I kept the same system than the old machine to put the system up and down. This 2 system can be moved with a screw.
G°) the automatic sawing machine 1°) Definition of the work The objectives of this machine were to design a machine which would be able to cut some great plane piece of wood in some small one, form 1 to 20 mm thick, with no one working on the machine. So I had to design a machine that can be easily piloted. First I began to design a machine still needed an operator. But after talking with the production manager here, I chose to make the blade movable. A circular blade would be able to move and cut the wood, which would be fixed on the table.
2°) the principle of the machine On this machine, people have to lock the piece of wood with the fixer system. This fixer system is link to a screw, and can be moved to adjust the dimension of wood to cut. The blade is fixed on a system which allows to adjust the width. Because the quality of the cut depend of this parameter. For a good cut, the blade has to be around 5 mm more high than the top of the piece of wood. The blade is moved by a motor. Page 24 on 27
David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
Picture 19 : General view of the machine
On this picture you can see the fixer system, in light green. Under the table is the blade system. The blade system is mounted on ball bearing runners. Then not a lot of energy will be lost in the movement.
Picture 20 : The system of blade
On the picture 18, you can see the system of blade. The blade is the Part in dark blue. The shaft will be moved by a motor not drawn here. The motor will take place under the system, and will move with it. The shaft and the motor will be linked by a system belt-pulley.
To protect the worker, I add a carter around the blade, on the top and the bottom of the machine. The security is quite important with that kind of machine, even if the worker has not to touch the machine when it works.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
3°) How to easily make this machine automatic? I tried to make this thing easy: The machine is piloted by three independent motors. One is making the blade turning, and has to be only put on or off. The second motor is to move the fixer, and adjust the dimension to cote. You can use an adjustable sensor, by example a light sensor, to detect the position of the fixer, or of the piece of wood. When the piece of wood is cut, it falls down through the hole in the base. Then the sensor sends information: no more wood. The motor push the fixer, until the piece of wood detects the wood again, and asks the motor to stop. By moving the sensor, you can easily adjust the dimension to cut. The third one can be pilot with only some end course sensors. I wasn’t in charge of the automatism command, but I tried to allow this work to be easy by designing in this way.
H°) Producing During the first week, to discover the factory, and waiting for an other assignment, I was affected to the production department. It was really interesting for me. As well as I spend my first industrial training in a small electricity company, I had never been into a production department. This short assignment allowed me to discover this world, and to be integrated into Samick‘s team. After finishing my first main project; which was to design the sanding machine, I came back to the factory, “downstairs” as we said in Samick Sports. I was able to discover all the different steps of the fabrication of a bow. The handle are made in USA, forged by external company, and send to Samick‘s factory, in Kimpo City. The limbs are made into the factory. It’s a mix of different woods, and some have carbon sheet, to improve the resistance and the quality. All the work on the bow is close to craftsman’s work. There are a lot of machine, but each part is carry by people of the factory, and a lot of different process can’t be automatism. By producing in this factory, I really understood the price of this bow. By example, I was allowed to make the adjustment of the alignment of the limbs and the sting. This is a really important adjustment for an archer, and this is made one handle by one handle. This is a quite long job, but an absolute need in the quality of the products.
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David MOULIN Industrial training - 4th year
2002/2003 Samick Sports, South Korea
III°) what I learned with Samick Sports The work experience that I had with Samick Sports allowed me to get a global view of the activity of a sport manufacturing company. First of all I discovered for the real first time the work of designing engineer. I was allowed to design some new machines, and it was the first time for me to do a such job. I did some draw into school, but no one to be really produced. So we didn’t take care for all little details. Now, with this work, I know now that designing a new machine is a very hard job. You have to think to all details. With that job I studied a lot of technologies I didn’t know, as linear guides, or pneumatics elements. I think it will be very useful for my future work as an engineer. I also learned how to have professional contacts. Since I work with Samick sports, I had many contacts with French customers. During the first week, I was able to produce in the factory. It was really interesting to see how people work in a such factory. Quality of Samick‘s bow is due to the knowledge of every Human workers here. This is not a big factory with a lot of people and where products were simply some products. Here it was a factory at human scale, and each bow was considered as a special one. It was the technical part. But this industrial training brings me more than some complements of my study. It was a really great adventure to live in a so far country, and I learned a lot of things about human relations. I think that I learned to be open minded, an absolute quality for engineer. As a foreigner I was able to discover the culture of this country, the hospitality of Korean people. It will be a very good international experience. I was able to discover a great world: Sport‘s world. I was an archer for so many years, and now to discover this world was so great. Samick Sports was one of my dreams, and now I can say that one of my dreams came true. It was so great to work in a such environment. I visited South Korea with M Kim, and I found this country really marvellous, and beautiful. It’s so strange to see a very old temple in the middle of a crossroad. The Korean culture is very rich; there were a lot of different aspect in this country. I think that I will remember this travel all my life long. I shot a lot of pictures, and I hope I will be allowed to come back again, another day. For me it was the first time I quit Europe, and the first time I travelled alone. This was one important thing of this training. I proved myself a lot of things, and particularly that I can live alone, really far of my family and my friends. I’m quite proud of my training. Personally, I enjoyed that training. I hope that Samick sports people, like M Cha and M Bong J Lee have appreciated my job, and that I will be allowed to keep in touch with them, at least by Email. As M Cha said to me “you come back in your country after 4 months of work here, but it won’t be the end of the story”. I thing it’s a good sentence to explain my general feelings.
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