• 마이크로전자및패키징학회지
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• 제26권3호
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• pp.63-69
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• 2019

전자부품에 대한 보드실장은 아직까지 솔더를 이용한 접합기술을 주로 이용하고 있다. 그러나, 솔더의 크? 및 피로특성으로 인한 접합부 내구한계로, 자동차 전장모듈에서는 반영구적인 접합기술인 프레스 핏(Press-fit) 접합기술 적용을 확대하고 있다. 프레스 핏 접합은 프레스 핏 금속단자를 보드내 쓰루 홀(Through hole)에 기계적으로 삽입하여 체결하는 접합기술로써, 적절한 금속단자의 소성변형으로 쓰루 홀 내부 표면접합을 밀착시킴으로써 강건한 접합을 유도한다. 본 논문에서는 보드내 쓰루 홀 크기 및 표면처리에 따른 프레스 핏 접합 특성 및 신뢰성을 솔더링과 함께 비교하기 위해, 보드 쓰루 홀 크기에 따른 삽입강도 및 삽발강도를 평가하였으며, 열충격 시험을 통한 실시간 저항변화를 통해 프레스 핏 및 솔더링 접합부의 저항변화를 관찰하였다. 또한, 각 접합부위 분석을 통한 프레스 핏 및 솔더링 접합열화를 분석하여 주요 파손모드를 고찰하고자 하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.226-231
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• 2004

Press fitting method for joining of a hybrid tube and steel ring with small teeth for automotive aluminum/composite hybrid propeller shaft was devised to improve reliability and to reduce manufacturing cost, compared to other joining methods such as an adhesively bonded joint, bolted joint or welded joint. To obtain high strength of the press fit joint, an optimal design method for the teeth was devised with respect to number and shape of the steel teeth. Torsional static, fatigue tests and finite element analysis of the press fit joint were performed with respect to experimental variables. The developed optimal design method predicted well the static torque capability and failure mode of the press fit joint. Also, it provided design guide line of press fit joint for improving torsional static and fatigue characteristics.

• 오토저널
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• 제15권1호
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• pp.89-99
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• 1993

In this research, important mechanical characteristics of Compliant Press-Fit Pin and PHT are studied through the analysis of deformation mechanisms of Press-Fit Pin and by elastic-plastic finite element method. The direct data for the optimal design of pin was obtained without interfere with the criterion on insertion force and retention force. Also, the insertion force and retention force of new type pin were measured by precision type tensile testing machine and it revealed good agreement with analytical results. In conclusion, it is believed that above results will contribute satisfactorily to the practical design of Press-Fit Pin.

• 한국해양공학회지
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• 제14권4호
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• pp.79-85
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• 2000

Press-fit pin connection is the solderless interference-fit between pins and plated through holes(PTH) in the printed curcuit board(PCB). Because of not only its simple assembly and absence of problems associated with soldering, but also its good mechanical and electrical characteristics, the press-fit pin connection technology has quickly gained wide acceptance in the telecommunications and computer industries. In this paper, the contact stress characteristics of the domestic CPF pin when inserted into the friction coefficients were compared and the stress variations of the compliant part of the pin, which have an influence on the performance, were displayed with the time and arc length after complete connected. It is supposed that the results will provide useful data to improve the performance of the pin-PCB interconnection mechanism.

• Clinics in Shoulder and Elbow
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• 제26권3호
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• pp.245-251
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• 2023

Background: For anatomic total arthroscopic repair, cementless humeral fixation has recently gained popularity. However, few studies have compared clinical, radiographic, and patient-reported outcomes between cemented and press-fit humeral fixation, and none have performed follow-up for longer than 5 years. In this study, we compared long-term postoperative outcomes in patients receiving a cemented versus press-fit humeral stem anatomic arthroscopic repair. Methods: This study retrospectively analyzed 169 shoulders that required primary anatomic total shoulder arthroplasty (aTSA). Shoulders were stratified by humeral stem fixation technique: cementation or press-fit. Data were collected pre- and postoperatively. Primary outcome measures included range of motion, patient reported outcomes, and radiographic measures. Results: One hundred thirty-eight cemented humeral stems and 31 press-fit stems were included. Significant improvements in range of motion were seen in all aTSA patients with no significant differences between final cemented and press-fit stems (forward elevation: P=0.12, external rotation: P=0.60, and internal rotation: P=0.77). Patient reported outcome metrics also exhibited sustained improvement through final follow-up. However, at final follow-up, the press-fit stem cohort had significantly better overall scores when compared to the cemented cohort (visual analog score: P=0.04, American Shoulder and Elbow Surgeon Score: P<0.01, Simple Shoulder Test score: P=0.03). Humeral radiolucency was noted in two cemented implants and one press-fit implant. No significant differences in implant survival were observed between the two cohorts (P=0.75). Conclusions: In this series, we found that irrespective of humeral fixation technique, aTSA significantly improves shoulder function. However, within this cohort, press-fit stems provided significantly better outcomes than cemented stems in terms of patient reported outcome scores. Level of evidence: III.

• Hip & pelvis
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• 제34권2호
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• pp.106-114
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• 2022

Purpose: While initial fixation using a press-fit of the acetabular cup is critical for the durability of the component, restoration of the hip center is regarded as an attributable factor for implant survival and successful outcome. In protrusio acetabuli (PA), obtaining both restoration of the hip center and the press-fit of the acetabular cup simultaneously might be difficult during total hip arthroplasty (THA). We tested the hypothesis that use of a medialized cup, if press-fitted, will not result in compromise of the implant stability and outcome after cementless THA of PA. Materials and Methods: A total of 26 cementless THAs of 22 patients with PA were reviewed. During THA, press-fit of the cup was prioritized rather than hip center restoration. A press-fit was obtained in 24 hips. A pressfit could not be obtained in the two remaining hips; therefore, reinforcement acetabular components were used. Restoration of the hip center was achieved in 17 cups; 15 primary cups and two reinforcement components; it was medialized in nine cups. Implant stability and modified Harris hip score (mHHS) between the two groups were compared at a mean follow-up of 5.1 years (range, 2-16 years). Results: Twenty-six cups; 17 restored cups and nine medialized press-fitted cups, remained stable at the latest follow-up. A similar final mHHS was observed between the restored group and the medialized group (83.6±12.1 vs 83.8±10.4, P=0.786). Conclusion: Implant stability and favorable results were obtained by press-fitted cups, irrespective of hip center restoration. THA in PA patients showed promising clinical and radiological results.

• 한국항행학회논문지
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• 제18권3호
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• pp.248-252
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• 2014

본 논문에서는 자동차 부품업체의 조립 공정에서 압입이나 볼트, 너트 체결에 주로 사용되는 프레스와 너트러너는 정밀도와 생산성 향상이 지속적으로 요구한다. 여러 대의 압입 시스템을 복합적으로 구성한 후 동기화를 통하여 일괄적인 제어를 수행하는 생산 시스템으로 시리얼 통신을 이용한 저속의 멀티 서보 프레스 시스템을 개발하였다. 그 결과로 정밀도와 생산성이 향상되었고 제품에 대한 품질향상을 이룰 수 있었다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.397-402
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• 2005

The NDT(Non-Destructive Testing) is valid for the defect detection of rolling stocks because it can be used to detect the defect in many invisible parts. For example, fatigue cracks are initiated in press fit parts that suffer from fretting fatigue damage such as the wheel seat and the NDT technique can detect those cracks. But the conventional ICFPD method can not apply to detect such cracks in press fit parts of the axle by some technical problems. In this study, we have introduced the new concept ICFPD method that can be applied in press fit parts of the axle. And we have shown the basic techniques of FEM about the new concept ICFPD method.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.481-485
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• 2000

A new type of compliant press-fit pin has been developed and evaluated for use packaging of electronic telecommunications equipments. Main requirements for design are defined the upper limit of pin insertion force and the lower limit of pin retention force. Upper limit of pin insertion force is set to protect the copper plate of the inner PTH wall. Lower limit of pin retention force is set to satisfy a wire-wrapping specification. Results are represented by insertion force and retention force variations according to the front angle, rear angle and material, etc.

• The Journal of Advanced Prosthodontics
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• 제7권3호
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• pp.233-239
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• 2015

PURPOSE. This study aimed to evaluate the fit of zirconia ceramics before and after veneering, using 3 different veneering processes (layering, press-over, and CAD-on techniques). MATERIALS AND METHODS. Thirty standardized zirconia CAD/CAM frameworks were constructed and divided into three groups of 10 each. The first group was veneered using the traditional layering technique. Press-over and CAD-on techniques were used to veneer second and third groups. The marginal gap of specimens was measured before and after veneering process at 18 sites on the master die using a digital microscope. Paired t-test was used to evaluate mean marginal gap changes. One-way ANOVA and post hoc tests were also employed for comparison among 3 groups (${\alpha}$=.05). RESULTS. Marginal gap of 3 groups was increased after porcelain veneering. The mean marginal gap values after veneering in the layering group ($63.06{\mu}m$) was higher than press-over ($50.64{\mu}m$) and CAD-on ($51.50{\mu}m$) veneered groups (P<.001). CONCLUSION. Three veneering methods altered the marginal fit of zirconia copings. Conventional layering technique increased the marginal gap of zirconia framework more than pressing and CADon techniques. All ceramic crowns made through three different veneering methods revealed clinically acceptable marginal fit.