Hiroyuki Nishimoto

Prediction Method for Temporal Change in Fiber Orientation on Cylindrical Braided Preforms

An advantage of braided fabrics is that the fiber bundle orientation angle, called the “braiding angle,” can be changed. Because the braiding angle affects the fabric’s mechanical properties, changing the angle is an important means of adjusting the stiffness distribution as required. However, when the braiding angle is changing from an initial braiding angle to a targeted braiding angle designated by the longitudinal velocity of the mandrel, some delay occurs before the actual braiding angle reaches the targeted braiding angle. Previously, several models have been developed in order to predict braiding angles, although a prediction method for a temporal change in braiding angle caused by the mandrel velocity change has not been presented. In order to obtain the temporal change in braiding angle under unsteady-state conditions, this paper presents a step response model in braiding angle on a cylindrical braided fabric. Furthermore, the method is verified with the experimental data. As a consequence, the model has proved effective for predicting fiber orientation on a cylindrical braided preform under unsteady-state conditions.

Comparison of Braiding Skills Between Expert and Non-experts by Eye’s Movement Measurement

A braiding rope is the Japanese traditional rope that a quality and beauty of them have depended on the skill and experience of a braider. In this research, the skill of a expert and two non-experts who practice the braiding everyday and every week, respectively were measured and compared through the eye’s movement measurement and observed the braiding rope quality. The measurement was carried out every month for three times. It was found that the expert show the constant of eye’s focus at the center of marudai plate and reveled a complete pattern of braiding rope. For two non-experts, their eye’s movement wobbled around marudai plate for all trials. However, the braiding speed and quality were developed by the regular training. There are no the defects in the ropes in the trial 2 and 3.

The Analysis of Removal Efficiency of Polishing Work Motion for Cold Forging Die with Simple Axial Symmetric Form

A stable quality control that accurately follows the specifications of the drawing is required in the tools that are used for mass production of parts, such as a forging die. In order to satisfy such parts processing requirements, establishment of die production system that can repeatedly recreate the same processing conditions, including the processing time, is necessary. Thus, it is of importance to prevent the processing discrepancy caused by proficiency levels of workers. In this report, we analyzed the work of an expert and non-expert, using a Finger TPS sensor system. The analysis results of the factors that influence their work efficiency are reported.

Comparison Knitting Skills Between Experts and Non-experts by Measurement of the Fabric Quality

This research focused on the developing the capacity of knitting skill. The comparison of skill between the experts with non-experts was studied. The movement of arms was measured to investigate the effect of arm movement on quality of knitting fabric. The experiment was carried out with a video camera to record and analyze the differences of the knitting speed and manner in knitting. The quality of the fabric was measured by a loop of fabric to see the consistency of the loop fabric, which is important for beautiful fabrics. The results revealed the procedure used to crochet knitting machines were very different in appearance, knitting and speed. The quality of the fabric was beautiful, similar to the use of the knitting as machine knitting. The main difference between them was only part of the seams.

The Analysis of Polishing Process of Cold Forging Die in Axial Symmetric Form and Axial Non-symmetric Form

In forging parts production, the die life is important for the production efficiency. If the die is fractured under production accidentally, it may cause a big damage to the productivity. One of die broken mode is a scratch on die surface caused by polishing in order to meet the design. It is for finishing the pre-mature die by polishing. It is required for more skillful craftspeople because the die life depends on damage of scratches. Therefore it is important to succeed their expertise constantly. It takes several years for craftspeople to be the expert on the job training. In this study, in order to accelerate their expertise transferring, we analyzed their expertise in focusing on quality of polishing in a forging part.

The Analysis of Repeatability of Polishing Work Motion for a Cold Forging Die with Simple Axial Symmetric Form.

In order to create the environment where effective transfer of proficient skill to the next generation, we conducted the analysis of the work of expert and non-expert in the polishing work, which influences the lifespan of a cold forging die. As most of polishing work employs files or abrasives, it can be described as a removal processing of the processed parts. In this study, polishing work is regarded as a removal processing, and used the impulse, which is attained as the product of multiplying polish processing force by operation time, for the comparison of removal volumes. As a result, the possibility for preventing the discrepancy in operation time by maintaining a constant processing force was shown.

Comparison Knitting Skills Between Experts and Non-experts by Measurement of the Arm Movement

This research focused on the developing the capacity of knitting skill. The comparison of skill between the experts with non-expert was study. The movement of arms was measure to investigate the effect of arm movement on quality of knitting fabric. The experiment was carried out on a video camera to record and analyze the differences of the knitting speed and manner in knitting. The quality of the fabric is measured by a loop of fabric to see the consistency of the loop fabric is important and beautiful fabrics. The result is a procedure used to crochet knitting machines are very different in appearance, knitting and speed. The quality of the fabric is beautiful, similar to the use of a knitting machine knitting. The main difference between them is only part of the seams.

Improvement of Needle Bar in Textile Machine by Hitting Process

The research conducted was to study the hitting process of a needle bar used within textile machinery and how to improve its efficiency and performance. A needle bar consists of a brass bar attached with a number of small pins. The primary focus was learning technique while straightening the needle bar. In order to join pins and brass bar together, the soldering is applied. The result from the heat transfer during soldering process can cause the brass pins to bend, which is undesirable for finished product. A soldering expertise uses hitting movement technique to modify and straighten the brass bar. Even though soldering process is the only step in making the brass bar; however, its method is considered very complicated and requires refinement and specialization from the maker.

Evaluation Method for Mechanical Properties of Polymeric Brush as Cushioning Material on Conveying Equipment

A steal bearing unit on conveying equipment in a turret punch press basically has noise problems. One of the solutions is a usage of polymeric brush instead of steal bearing, which works as the cushioning material. However, the loading characteristic is not clear because the concrete evaluation method for polymeric brush is not established. The variation on the head of each fiber in the brush makes the deviation in terms of the mechanical properties. Besides, our expectation to the heavy load is increasing in recent years. Therefore, the purpose of this study is to propose new method to evaluate the mechanical properties of the polymeric brush. Basically, the start point of stress increase on each fiber varies because of the different length of fibers on one brush. It makes difficulty on zero point adjustment according to each brush with different properties. Then we developed new zero point adjustment based on comparing with preloading and unloading characteristics. The experimental results show the validation that new evaluation method improves the predictive accuracy and imply more efficient designing in the conveyer equipment.Copyright