Abstract: A covering device includes a surface-indented covering member with at least one groove formed in its surface. The at least one groove has a depth in the range of 0.2 to 0.4 microns and a width which is not more than the depth thereof and is greater than 0 and not more than 0.4 microns. Another covering device includes a surface-indented covering member with a groove formed in its surface, and a covering material disposed on the surface of the member to cover at least the groove thereunder. The depth of the groove is in a range from 0.12 to 0.3 microns, and the width thereof is not more than the depth and is greater than 0 and not more than 0.3 microns. The covering material is transparent and has a refractive index smaller than that of the covering member.

Abstract: A plastic optical element with good dimensional accuracy and no strain is produced by providing a mold having a cavity corresponding to a shape of the optical element and a feed passage which communicates with said cavity, at least one side of which mold for forming one surface of the optical element is made of a light transmitting material so that light can pass through said material into the mold cavity, charging a photocurable plastic material through said feed passage into said cavity, irradiating a central part of said cavity with light which initiates a photocuring reaction, and enlarging the light in the form of a ring until the lighted area reaches the periphery of the cavity so as to cure the entire photocurable plastic material. The light irradiation is carried out while a supplementary portion of the photocurable plastic material is maintained in said feed passage.

Abstract: A method for manufacturing an electronic device having therein a lead frame and a vibration-generating element integrally provided on the lead frame. The lead frame and the element are first provided in a metallic mold assembly comprising an upper mold portion and a lower mold portion, the upper and lower mold portions respectively having recess portions so as to form a cavity when the upper and lower mold portions are assembled with each other. A first sealing material is injected into the cavity so that the element is covered by the injected first sealing material, the first sealing material having a shrinkage property and a low adhesion property. After solidification of the injected first sealing material, they are removed from the mold assembly and then immersed in a second sealing material at a vacuum state so that the second sealing material is impregnated between the first sealing material portion and the lead frame.

Abstract: A lever pivoted at a support point receives force from pressure receiving members located at two positions along the direction of flow of resin in a flow passage without a metal mold. A physical property or condition of the resin flowed into the metal mold is determined as a function of the time during which the resin flows between the two pressure receiving members and of a difference pressure acting on the lever at the two positions.

Abstract: A mold clamping device includes a frame, a fixed base for supporting a first mold, the fixed base being fixedly mounted on the frame, a movable base for supporting a second mold, the movable base being movably mounted on the frame in confronting relation to the fixed base, first means on the frame for driving the movable base to move rectilinearly toward and away from the fixed base, a cam follower supported on the movable base, a cam supported on the frame and having a cam surface held in contact with the cam follower, and second means for driving the cam in a mold clamping stroke to displace the cam follower for enabling the movable base to clamp the second mold firmly against the first mold on the fixed base, the cam surface being defined by a cam follower displacement curve having a gradient which is greater at an initial stage of the mold clamping stroke and becomes smaller as the mold clamping stroke progresses.

Abstract: An aluminum electrolytic capacitor provided in a container including a resin casing integral with a pair of terminals perforating therethrough and a resin lid coupled to the resin casing with an element which includes an anode aluminum foil, a cathode aluminum foil and separators, which are superposed in layers, so that the anode aluminum foil and one of the terminals are connected electrically through a lead, the cathode aluminum foil and the other lead are connected similarly through another lead, and an electrolyte is impregnated into the separators, thereby obtaining the aluminum electrolytic capacitor which is well sealed, is very heat resistant and will not short circuit.

Abstract: A press molding apparatus and its method of operation for making an information carrier disc which comprises the steps of maintaining a mass of granular transparent synthetic material in a vacuum, radiating heat from an infrared heating unit to plasticize the synthetic material, and press-molding the plasticized synthetic material.

Abstract: A combined molding and assembling apparatus which comprises a conveyor movable from one position to another position spaced apart from such one position, a pallet frictionally engageable with the conveyor for movement together therewith, a catch mechanism releaseably engageable with the pallet to hold the pallet at a working position, a molding machine fixedly mounted on a bench of the apparatus adjacent the conveyor and including a movable plate movable in a direction perpendicular to the direction of movement of the conveyor means for selectively closing and opening a mold assembly, and a handling machine including a head capable of moving selectively into and away from the space, in which the mold assembly operates, during the opening of the mold assembly.