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Volume 29, Issue 344
Displaying 1-9 of 9 articles from this issue
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Shear Stress in the Crack-type CuttingAkio KAMOGAWA1963 Volume 29 Issue 344 Pages 611-616
Published: September 05, 1963
Released on J-STAGE: February 16, 2010
JOURNAL FREE ACCESSBy examining cutting surface profile, the shear stress of plastics in the crack-type cutting was determined, that is,
τc=Fc/A·sin φc·cos φc
τc=Shear stress
Fc=Cutting resistance in the horizontal direction
A=Area of cut
φc=Fracture angle
The results show that the shear stress of epoxy-resin is lower than that of acrylic resin.View full abstractDownload PDF (2960K) -
Mineko IWASAKI1963 Volume 29 Issue 344 Pages 617-622
Published: September 05, 1963
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe relation between the surface roughness and Abbott's bearing curve is examined by introducing a model of the profile curves of some finished surfaces. Profile curves of almost all kinds of finished surfaces, except such special surfaces as milled ones and turned ones by a round nose tool, can be assumed to be made up of a series of triangles, the height of which is nearly equal with each other. In these cases the bearing curve can be drawn as a main straight line with broken lines at either end of it, and the broken lines disappear when the peaks and the valleys of the cross sectional curve are on two straight lines parallel to the center line of the cross sectional curve. The existence of the broken line has a secondary effect on the estimation of the center line average roughness, while it has important effect on the estimation of the maximum height roughness. Hence the center line average roughness can easily be calculated graphically, neglecting the broken lines of the bearing curve.
It is found that the above theory can be applied for the surfaces which are finished by abrasive grains, that is, by emery cloth, abrasive belt, grinding wheel and sand blasting.View full abstractDownload PDF (779K) -
Statical Friction of Ball Screw under Heavy LoadZenzaburo MURASE1963 Volume 29 Issue 344 Pages 623-632
Published: September 05, 1963
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIn this part, the results of the studies on the moment due to the statical friction of a ball screw under heavy load by the double nut procedure are reported and the followings are included.
1) The relation between the moment due to the statical friction of a ball screw and the load acting upon it is expressed by a linear equation.
2) The statical friction of the ball screw is mainly composed of sliding friction.
3) The efficiency of the ball screw is over 95 %, and sometimes reaches to 99%.
4) The coefficient of the statical friction lubricated with motor oil is about 0.003.
5) The greater the curvature of the screw surface profile at the contact point of the lace-way and the ball, the better for the frictional character of the ball screw.
6) To use motor oil is most suitable for the diminishing of the moment due to the statical friction of the ball screw under light load range, and grease is most suitable under heavy load range.
7) A slight decrease of the radius or the number of balls inserted between the laceways influences little to the moment due to the statical friction.
8) A slight difference in the accuracy of the lace-way gives little influence to the moment due to the statical friction lubricated with grease.View full abstractDownload PDF (1382K) -
Hiroshi SAITO1963 Volume 29 Issue 344 Pages 633-638
Published: September 05, 1963
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSIn order to study further differences of the shearing force and the side-force acting on the die-edge and those of other phenomena, the experiment was done of seven cases, i.e. cases of using six sorts of lubricants and a dry working.
The sheets of 14 mm thickness of nine different material were tested with the apparatus shown in Fig. 1 and 2.
Generally, for the most materials, higher the lubricating capability of lubricant, smaller the maximum value of shearing force and side-force becomes (Fig. 5·1, 5·2), and it is found to be a tendency that the sheared band of test pieces under the punch shows remarkable decrease (Fig. 6·1, 6·2) and upon the dies shows appreciable reduction (Fig. 7·1, 7·2).View full abstractDownload PDF (2734K) -
Variation of Chip Formation with Tool-Chip Contact LengthEiji USUI1963 Volume 29 Issue 344 Pages 639-648
Published: September 05, 1963
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSThe variation of chip formation with the artificial restriction of tool-chip contact length in machining with cut-away tools is analyzed based upon the slip line theory proposed in the previous papers.
The analysis appears to be in good agreement with experimental results in slow speed machining, however, it is not so well supported by experiments in high speed machining of steel.
In high speed machining, the slip line construction of the plastic field within the chip appears to be greatly affected by the temperature distribution, thus by the strength distribution in the plastic field.
The tool face friction in dry cutting of steel is found to be so severe that the real area of contact between the tool and the chip is very close to the apparent area. The reason why large shear angles and continuous chips are obtained in high cutting speed may be attributed to the lubricating action of a lowered strength region of the plastic field near the rake face due to higher cutting temperature.View full abstractDownload PDF (17130K) -
Kazuo NAKAYAMA, Kiyoshi TAMURA1963 Volume 29 Issue 344 Pages 649-652
Published: September 05, 1963
Released on J-STAGE: February 15, 2010
JOURNAL FREE ACCESSThe micro-Vickers-hardness test of the chips produced in the cuttings of steels and brass under usual cutting conditions reveals that:
(1) Within the spread of ± 4 %, the hardness is uniform all over the cross-section of a chip, and the cutting conditions have no effect on the hardness of chip.
(2) The hardness is proportional to the tensile strength for each kind of chip.
(3) (1) and (2) means that the chip is practically an ideally plastic material.
(4) Using the relation derived experimentally and found to be reasonable theoretically, the shear stress on the shear plane during the cutting of steel can be estimated from the hardness of the chip produced with a satisfactory accuracy. In the cutting of brass, however, the shear stress is somewhat lower than that estimated from this relation because of the softening by the temparature-rise during the cutting.View full abstractDownload PDF (2755K) -
The Mechanism of the Single Point Cutting Tool with Side-cutting Edge AngleTaketo YOKOYAMA, Fumio HASHIMOTO, Naoki YAMASAKI1963 Volume 29 Issue 344 Pages 653-661
Published: September 05, 1963
Released on J-STAGE: February 15, 2010
JOURNAL FREE ACCESSIn the case of the single point cutting tool with side-cutting edge angle, the relationship between the chip flow angle and the cutting resistance and frictional force on the rake face of tool has been investigated in the part 1 and 2 of this report.
Since the mechanics of the single point cutting tool is not sufficiently made clear, notwithstanding the orthogonal cutting theory have made steady progress, the examination on the three-dimensional cutting is applied, in this part 3, in the same way as Dr. Shaw's examination about the oblique cutting.
That is, the effective rake angle of the single point cutting tool and effective shear angle are geometrically researched, and the formulae calculating the mean shear stress, shear strain and others are led.
Moreover, the experimental results calculated with these formulae are investigated in comparison with the orthogonal cutting.View full abstractDownload PDF (6535K) -
[in Japanese]1963 Volume 29 Issue 344 Pages 662-667
Published: September 05, 1963
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSDownload PDF (1255K) -
1963 Volume 29 Issue 344 Pages 670-672
Published: September 05, 1963
Released on J-STAGE: June 30, 2009
JOURNAL FREE ACCESSDownload PDF (606K)
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