摘要:
A mechanical part comprises a sliding section and a sleeve section which are prepared separately. The sliding section is made of a wear resisting material such as ceramics and formed with a planar sliding surface at one of the sides thereof. The sliding section is further formed with a joining portion at the outer periphery thereof. The sleeve section is made of metal and formed with a joining portion at the inner periphery thereof. The joining portions of the sliding section and the sleeve section are joined by interference fit or the like, whereby to allow the sliding surface of the sleeve section to be formed into a crowned shape.
摘要:
A solder piece that has a rectangular parallelepiped shape formed by a punching process. Any one of the four surfaces of the rectangular parallelepiped other than the surface on which the shear droop portion generated by the punching process is formed and a surface opposite to the surface on which the shear droop portion is formed is sucked surface.
摘要:
The invention is a cellulose derivative wherein some of the carboxyl groups of the cellulose derivative carboxymethylcellulose are replaced with —CO—NH—X—CO—Y—Z, and a hydrogel of the same. In the formula, X is a C1-10 divalent hydrocarbon group, Y is a divalent group derived from polyalkylene oxide having oxygen atoms at both ends, and Z is a C1-24 hydrocarbon group or —CO—R4, where R4 is a C1-23 hydrocarbon group. The hydrogel has excellent viscoelasticity and can be injected into prescribed sites with injecting devices such as syringes, and it can thus be utilized as a medical gel or adhesion barrier.
摘要:
A cellulose derivative which has a suitable elastic modulus and viscosity when it is dissolved in water and is useful as an adhesion barrier.The cellulose derivative has a molecular weight of 5×103 to 5×106 and is composed of a repeating unit represented by the following formula (1): wherein R1, R2 and R3 are each independently selected from the group consisting of the following formulas (a), (b), (c) and (d) in predetermined amount: (X in the formula (c) is an alkali metal, and R4 and R5 in the formula (d) are each independently an alkyl group or alkenyl group having 10 to 28 carbon atoms).
摘要:
This discloses an electronic component of a miniature size to be used as e.g. automobile engine peripheral components, such as an exhaust gas oxygen sensor, a heat sensor, and a heater. More specifically, the invention provides an electronic component integral with a heat resistant terminal that is pressure-fitting or shrink-fitted on a ceramic element of the electronic component. This electronic components shows great mechanical and electrical performance, withstanding the high temperature environment over 400 and up to 800.degree. C. to which the ceramic element of the component required expose.The terminal incorporated in this high temperature electronic component comprises a plurality of metal wire leads that electrically connect to a surface of a bar-like ceramic element, at least two ceramic insulators that surround the leads, and a thermal resistant metal ring that shrink-fits or pressure-fits around the ceramic insulators so that the metal leads press in a radial direction holding the element firmly.The thermal resistant metal ring to be used for this shrink fit or pressure fit is preferably made of an alloy, such as Incoloy 909, Inconel 650, and Waspaloy, and the like, thereby preventing the metal leads from coming off at high temperature.The terminal integrated with the ceramic element by the shrink fitting method according to the invention, minimizes the number of parts, attaining a miniaturization of such high temperature electronic component at a low cost.
摘要:
A wire electric discharge machining method capable of improving a machining accuracy of a corner portion. A machining feed speed is gradually reduced from a point A before entering a corner portion machining between points C and D, and in the corner portion between points C and D the machining is performed at a fixed feed speed. The feed speed is gradually increased from the point D, where the machining of the corner portion is completed, and is restored to the original speed. In accordance with the change of the feed speed, an off-state time of the voltage applied between a wire and a workpiece is increased from a point B and is reduced from a point E after completing the corner portion machining, to restore the original off-state time at a point F. Further, a flow rate of machining fluid is reduced depending on the corner portion. The feed speed, the off-state time and the flow rate of the machining fluid are controlled by automatically changing them in dependence on a curvature of the corner portion. A warp of the wire electrode is substantially prevented at the beginning of and during the corner portion machining, to thereby improve the machining accuracy of the corner portion.
摘要:
A ceramic-steel joined body includes a ceramic body of silicon nitride, zirconia, silicon carbide, boron nitride, and alumina. The joined body also includes a steel body which has its surface carburized so that the hardness of the surface is greater than the hardness of the inside of the steel body. The ceramic body and the steel body are thermally joined using a brazing material of Ag--Cu--Ti, Ag--Cu--In--Ti, Ag--Ti, Cu--Ti, Ag--Cu--Ni--Ti, Ag--Cu or Ag--Cu--In.
摘要:
A wire disconnection position detecting apparatus of a wire feed path in which wire disconnection is caused and the causes of the disconnection in this section set in advance. Upon disconnection of a wire, as a voltage for disconnection position detection applied to the wire through a conductor is detected by a microprocessor through an electrode disposed on the lower-course side of the conductor (S3), the value in a register for rewinding amount storage is updated, with rewind of the wire by a rewinding motor, in accordance with pulses delivered from a rotary encoder (S4, S5), and thereafter, the rotation of the motor and the application of the voltage are stopped when a cut end of the wire passes the electrode (S6 to S8). Based on the result of comparison between a detected rewinding amount and the distances between the electrode and individual parts arranged along the wire feed path, the microprocessor detects the section of the wire feed path in which the wire is snapped (S9), and displays the wire disconnection section and the causes of the disconnection in this section, in the form of messages, on a CRT screen (S10).
摘要:
A wire discharge machining power source controls an average machining voltage value applied between a wire electrode (P) and a workpiece (W) to be zero to prevent galvanic corrosion of the workpiece (W). A reverse voltage application time control circuit (2) detects the average machining voltage value and generates a pulse (S5) having a pulse width corresponding to a detected value. A reverse voltage regulating circuit (1) detects a difference between a reference voltage and a voltage applied between a transistor (T2) and a resistor (R2) upon application of the reverse voltage through the transistor (T2) and the resistor (R2), and supplies a difference signal, which corresponds to the detected difference, as an ON control signal to the transistor (T2) for a period corresponding to the width of the pulse (S5), thereby controlling the reverse voltage value and setting the average machining voltage value to zero.
摘要:
A ceramic-aluminum alloy composite in which residual stress between the ceramic and aluminum components is substantially eliminated and strong cohesion is provided between the components of the composite over a wide temperature range. The composite of the invention is an integral combination of a ceramic element, a metallized layer, a cladding layer and an aluminum alloy layer. The metallized layer and the cladding layer are formed in that order on the surface of the ceramic element. The aluminum alloy layer is formed adjacent the cladding layer by pouring and solidification of a molten aluminum alloy. The metallized layer is a thin metal layer formed by any of vapor deposition of a metal, a high-melting metal method, and an activated metal method. The cladding layer is a three-layer laminated structure having top and bottom layers of Cu, Ag or Al and an intermediate layer of a metal dissimilar to the top and bottom layers. The ceramic element is preferably one of Si.sub.3 N.sub.4, SiC, Al.sub.2 O.sub.3, ZiO.sub.2, mica, LAS and crystalline glass.
摘要翻译:一种陶瓷 - 铝合金复合材料,其中陶瓷和铝组分之间的残余应力基本上消除,并且在宽温度范围内在复合材料的组分之间提供强的内聚力。 本发明的复合材料是陶瓷元件,金属化层,包覆层和铝合金层的整体组合。 金属化层和包覆层依次形成在陶瓷元件的表面上。 铝合金层通过熔融铝合金的浇注和固化形成在包覆层附近。 金属化层是通过气相沉积金属,高熔点金属法和活化金属法形成的薄金属层。 包层是具有Cu,Ag或Al的顶层和底层以及与顶层和底层不同的金属中间层的三层层压结构。 陶瓷元件优选为Si 3 N 4,SiC,Al 2 O 3,ZO 2,云母,LAS和晶体玻璃之一。