Abstract: The present invention relates to an under bump structure comprising a wafer surface including a plurality of pads; a plurality of passivation layers covering the wafer surface around the pads; a dielectric layer covering the wafer surface and the passivation layers, each of the passivation layer and the dielectric layer having a first opening at a position corresponding to that of each pad for exposing the pad; and an under bump metallurgy layer covering the dielectric layer, the pads and the passivation layers to connect the pads.

Abstract: A silicon wafer has a B-stageable underfill material deposited on the active face of the wafer. The B-stageable underfill comprises a first composition with a lower curing temperature and a second composition with a higher curing temperature, characterized in that the first composition has been fully cured.

Abstract: A semiconductor chip having a planar active surface including an integrated circuit protected by an inorganic overcoat; the circuit has metallization patterns including a plurality of contact pads. Each of these contact pads has an added conductive layer on the circuit metallization. This added layer has a conformal surface adjacent the chip, including peripheral portions of the overcoat, and a planar outer surface; this outer surface is suitable to form metallurgical bonds without melting. The chip contact pads may have a distribution arrayed in the center of the chip in close proximity to the chip neutral line; the distribution may leave an area portion of the active chip surface available for attaching a thermally conductive plate. The chip may further have a non-conductive adhesive layer over the overcoat, filling the spaces between the added conductive layers on each contact pad.

Abstract: A semiconductor device, wherein the lowering, in comparison with a background art, of the resistance of a source line is achieved and a manufacturing method for the same are obtained.

Abstract: A system and method is disclosed for providing mechanical planarization of a sequential build up substrate for an integrated circuit package. A planarization plate is placed in contact with an uneven external surface of a dielectric layer that covers underlying functional circuit elements and filler circuit elements. A heating element in the planarization plate flattens protruding portions of the external surface of the dielectric layer to create a flat external surface on the dielectric layer. After the flat external surface of the dielectric layer has cooled, it is then covered with a metal conductor layer. The method of the present invention increases the number of sequential buildup layers that may be placed on a sequential buildup substrate.

Abstract: A wiring substrate (1) comprises an insulating base (10) with connection holes (11), buried conductors (12) provided in the connection holes (11) without reaching a rear surface of the insulating base (10), and wiring layers 14 connected to the buried conductors (12). The buried conductors (12) thicken the wiring layers (14), and can form aligning parts (110) on the rear surface of the connection holes (11) to be used for three-dimensional mounting structure. Each wiring layer (14) includes thin terminals (14A), wirings (14B) and thick electrodes (14C). Not only the terminals (14A) and wirings (14B) but also the buried conductors (12) are raised by the same manufacturing process. A semiconductor element (2) is attached to the electrodes (14C) of the wiring substrate (1).

Abstract: A semiconductor apparatus and method are provided. According to an embodiment, the apparatus includes a first contact extending from a first conductive element disposed in a substrate. A second contact extends from a second conductive element disposed in the substrate at least to a lower limit of a capacitor well. The capacitor well is formed in a pre-metal dielectric layer disposed on the substrate. The second contact is shorter than the first contact. The height of the capacitor structure may be substantially the same as the height of the pre-metal dielectric layer. A first metal layer is disposed on the pre-metal dielectric layer. Thus, the capacitor structure may extend from the lower limit of the capacitor well to the first metal layer. The first contact extends to the first metal layer.

Abstract: Disclosed is a semiconductor device comprising: a multiplicity of wiring levels, each wiring level comprising conductive wires and a multiplicity of conductive fill shapes embedded in a dielectric; at least some of the fill shapes in at least two adjacent wiring levels being co-aligned; and where the fill shapes on adjacent levels are aligned, one or more conductive vias extending between and joining each co-aligned fill shape in each adjacent wiring level. The joined fill shapes serve to reinforce and support the dielectric, which may be a non-rigid or low-k dielectric.

Abstract: A novel contact structure and method for a multilayer gettering contact metallization is provided utilizing a thin layer of a pure metal as the initial layer formed on a semiconductor cap layer. During formation of the contact structure, this thin metal layer reacts with the cap layer and the resulting reacted layer traps mobile impurities and self-interstitials diffusing within the cap layer and in nearby metal layers, preventing further migration into active areas of the semiconductor device. The contact metallization is formed of pure metal layers compatible with each other and with the underlying semiconductor cap layer such that depth of reaction is minimized and controllable by the thickness of the metal layers applied. Thin semiconductor cap layers, such as InGaAs cap layers less than 200 nm thick, may be used in the present invention with extremely thin pure metal layers of thickness 10 nm or less, thus enabling an increased level of integration for semiconductor optoelectronic devices.

Abstract: A method of manufacturing a printed circuit board through-hole connection includes forming a through-hole by removing material from the first side of the printed circuit board until the backing and then slightly into the first side of the backing providing a hole. Next, plating through the hole connecting the backing layer, ground layer, and signal layer. Now the plating of the signal layer is removed without removing the connection from the ground layer to the backing. Finally, the hole is filled from the first side of the printed circuit board.

Abstract: In a semiconductor device having a wire structure, the thickness of a first insulation film substantially corresponds to the depth of a contact hole. A surface of a second insulation film serves as a bottom face of a wire groove. Regarding the contact hole, only a side wall portion intersecting a direction of the wire groove has a substantial taper angle. This configuration can be attained under conditions where an etching selectivity of the first insulation film to the second insulation film is set to be slightly lower and a portion of the second insulation film where a opening edge of an opening portion is exposed is slightly etched during etching process of the wire groove. With a semiconductor device having this structure, a conductive material embedding characteristic can be enhanced, while preventing possibility of short-circuit even when an interval between wires is reduced.

Abstract: A lead pin with an Au—Ge based brazing material including a lead pin made of a copper-containing metal is provided. The lead pin including a joining surface to a substrate, at least the joining surface of the lead pin being plated with nickel and gold, and including an Au—Ge based brazing material being fused on top of the gold plating, wherein the lead pin after plated with nickel is subjected to heat-treatment and then plated with gold to fuse the brazing material.

Abstract: A semiconductor device comprising: a semiconductor element having a plurality of electrodes; a passivation film formed on the semiconductor element in a region avoiding at least a part of each of the electrodes; a conductive foil provided at a given spacing from the surface on which the passivation film is formed; an external electrodes formed on the conductive foil; intermediate layer formed between the passivation film and the conductive foil to support the conductive foil; and wires electrically connecting the electrodes to the conductive foil; wherein a depression tapered in a direction from the conductive foil to the passivation film if formed under a part of the conductive foil that includes the connection with the external electrodes.

Abstract: A radiation-emitting semiconductor component has a semiconductor body containing a nitride compound semiconductor, and a contact metallization layer disposed on a surface of the semiconductor body. In this case, the contact metallization layer is covered with a radiation-transmissive, electrically conductive contact layer. The radiation generated is coupled out through the contact metallization layer or through openings in the contact metallization layer.

Abstract: A method of forming an identifying mark on a semiconductor wafer. The identifying mark, for example a bar code or a character of patterns or words, is formed on the side wall of the semiconductor wafer to avoid contamination and the creation of failure dies during the formation of the identifying mark.

Abstract: A resist pattern for alignment measurement being shrunk by a heat flow comprises a plurality of positive type or negative type line patterns. Widths of spaces between the line patters are greater than twice those of the line patterns. Alternatively, the resist pattern comprises a box-shaped or slit-shaped measurement pattern and a pair of box-shaped or slit-shaped auxiliary patterns provided inside and outside the measurement pattern, respectively.

Abstract: In a method of producing a data storage medium with an optically writeable and readable information carrier which comprises a polymer film whose refractive index can be altered locally by heating, to the polymer film being assigned an absorber which is set up so as at least partly to absorb a write beam and to emit the generated heat at least partly, locally, to the polymer film, first of all a storage film (11) is prepared. The storage film (11) comprises the polymer film (34) and the absorber (35) assigned to the polymer film (34). Subsequently, the storage film (11) is adapted to the geometry provided in the data storage medium.

Abstract: A method and apparatus are disclosed for slip-form casting a concrete product, the product being made from at least two different grades of concrete so that the concrete mix grade can be changed in an uninterrupted fashion during casting at a desired point along the length of the casting bed.

Abstract: Disclosed herein is a system for momentarily heating the surface of a mold and system thereof. The system comprises a casting material feeder, upper and lower molds, a water-cooled system, first and second cores, a voltage generator, a electric resistance heater, a controller, an injection molding control, an air and gaseous fuel mixture and supply unit, an interface and a control panel. The casting material feeder serves to supply molten casting material. The injection molding control serves to control the upper mold and the lower mold. The air and gaseous fuel mixture and supply unit serves to supply compressed air and gaseous fuel simultaneously. The gaseous fuel mixture and supply control serves to control the operation of the air and gaseous fuel mixture and supply unit. The interface serves to interface the injection molding control and the gaseous fuel mixture and supply control. The control panel serves to visually display the control, condition and operation of the components of the system.

Abstract: The present invention provides a servo drive type automatic mold-adjusting control method. When a toggle of a mold-clamping unit of a servo drive type injection molding machine stretches straight, if a mobile moldboard exactly contacts a static moldboard, the mold-clamping force will be near zero at this time. Assume the toggle recedes a distance and a mold-adjusting board and the mobile moldboard move forwards another distance and are then fixed, if the toggle stretches straight at this time, the mobile moldboard cannot move forwards continually because it already contacts the static moldboard. Therefore, advance of the motor will result in deformation of tie bars, hence building the mold-locking force.

Abstract: The present invention concerns an adjustable shroud useful with any melt spinable polymers during their production. The adjustable shroud can be produced from different embodiments such as hinged wall sections, bellows, or collapsible or nesting walls. The adjustable shroud may be controlled by means of hydraulics, pneumatics, mechanical worm screws powered by an electrical motor or manually, or any other suitable means obvious to those skilled in the art. The length of the adjustable shroud functions such that it extends toward or away from the spinneret depending on the desired length of the shroud.

Abstract: A method is provided for producing a molded part that is deep drawn from a thermoplastic foil. An outer surface of the thermoplastic foil is provided with a positive depth structure, under the effect of heat and pressure, by means of a stamping or embossing roller that has a negative depth structure. In at least one extent of a surface of the embossing roller, the negative depth structure of the roller is compressed in such surface regions thereof that effect a stretching of the foil during deep drawing. Subsequently, at least a portion of the foil is deep drawn.

Abstract: A rapid throughput method for the preparation, analysis or both of libraries of material samples is provided. According to the method, a plurality of samples is provided. The plurality of samples is then formed into a plurality of films. Thereafter, the plurality of films is plastically deformed. Preferably, the plurality of films is deformed into a configuration appropriate for testing of properties or characteristics of the samples.

Abstract: For observing a flow of molten resin in an injection molding apparatus, a transparent cylinder, which is formed of transparent glass or transparent plastic material, is used in place of a mold of the apparatus. Because filling the transparent cylinder with the molten resin up to the cylinder's full capacity will burst the cylinder, the molten resin injection is terminated on the way when the injected molten resin has occupied a predetermined percentage, in a range of 50-90%, of the total volume of the cylinder, so that a burst of the cylinder can be avoided. The transparent cylinder provides for an increased resin-flow observation range because of its transparency, and can be less expensive because it is formed of inexpensive glass or plastic. As a consequence, there can be provided an efficient resin-flow observing experiment apparatus at lower cost.

Abstract: An apparatus for manufacturing lightweight concrete composite blocks includes a form, a station conveyor, a form-loading station, a form assembly station, a curing oven, and a block removal station. The station conveyor conveys the form or a multitude of forms around the apparatus in a continuous loop to produce a desired rate of production of lightweight concrete composite blocks. The form-loading station fills the form with a lightweight concrete composite. The form assembly station assembles the form to seal the composite within the form. The curing oven cures the lightweight concrete composite into a lightweight concrete composite block. The block removal station removes the lightweight concrete composite block from the form prior to the return of the form to the form-loading station for re-use.

Abstract: An adjustable core pin, and method of use thereof, for molding vials for use in levels, including an elongate rod with a barrel-shaped distal section having a crest at its cross section with the greatest diameter and a rod retainer with a cavity which receives the rod such that the distal end of the rod projects from a rod retainer distal opening, the rod being adjustable in relation to the rod retainer so that the crest can be adjustably placed at a preferred position in a molding cavity for vial molding.

Abstract: The invention concerns a continuous manufacturing method which consists in producing a blank (E) by extrusion, bringing said blank to a temperature for molecular orientation, passing said blank around a radial expansion mandrel (12); gauging and cooling while subjecting the blank to axial traction. The radial expansion produced on the mandrel (12) is partial so that the internal diameter (B) of the blank (E), when it leaves the mandrel, is less than the nominal internal diameter (D) of the finished tube, performing an additional radial expansion of the blank, up to its nominal diameter, by internal fluid pressure. In permanent operating conditions, the inner surface of the blank (E) is no longer in contact with the mandrel (12).

Abstract: This invention includes a method of producing a thin, oriented layer of polymer material. The material is preferably produced by the method of introducing a shearing flow to a free surface in a predominantly monomeric solution of the self-assembling polymer sub-units, and inducing polymerization or growth of the monomer while in this shearing flow. The system for forming the oriented layer of material provides relative movement between a delivery system and the substrate on or over which the material is deposited. The rate of flow of the material from the delivery system and the relative velocity between the deposition surface and the material as it is delivered to the surface are controlled to properly orient the material at the desired thickness. These rates can be adjusted to vary the properties of the film in a controlled manner. Preferred embodiments include either angular or linear relative movement between the delivery system and the substrate.

Abstract: The invention relates to a process for determining pressing parameters for the pressing of compacts, whereby in one step a test compact is brought to the required density in order to achieve the nominal pressing force, and in order that consequently the machine is in a balanced deflected condition with regard to this nominal pressing force. In next step, in case a nominal height (hsi,Nominal) deviates from a height (hsi,Measure) measured on the test compact, there will be determined for the next pressing operation a required height (HPowderNew) of the material to be pressed in the pressing mold.

Abstract: Anti-microbial activity is permanently applied to the surfaces of polyolefin objects by incorporating anti-microbial metals and metal salts into the surfaces. This is achieved by coating the selected surface of a preformed polyolefin part with the anti-microbial composition of this invention and then heating the surface of the object to fuse the coating into the polyolefin wall. Alternatively, the composition can be applied to the interior surface of a manufacturing mold at the start of the molding cycle from where it is incorporated into the wall of the molded object during its manufacture. The antimicrobial composition comprises from 0.5 to 5 weight percent of an anti-microbial additive in a hydrocarbon resin or polyolefin having a low melt index. This composition can be diluted with an organic or aqueous carrier for ease of application.

Abstract: A method and apparatus for forming patterns in a flat, plastic material, such as, for example sheet vinyl, linoleum, and other flat sheet floor covering. The apparatus comprises a router die and trimmer base affixed to a router machine. The router die is comprised of two guiding members, a first guiding member that directs the router blade between an edge of a pattern and an edge of an overlay. A second guiding member follows the blade after the groove is cut.

Abstract: Windshield wiper apparatus and methods in accordance with various embodiments of the instant invention include forming a new edge on a worn wiper blade. The new edge increases the effectiveness of the wiper blade and thus extends the useful life of the wiper blade. An apparatus in accordance with one embodiment of the instant invention can be employed to form the new edge in accordance with one of various methods including trimming a worn edge from the wiper blade as well as molding a new edge onto the worn wiper blade. In accordance with yet another embodiment of the instant invention, a windshield wiper assembly includes a wiper blade and a heating element supported on the windshield wiper assembly, wherein the heating element is configured to heat the wiper blade so as to keep the wiper blade substantially clear of ice, snow and the like during winter driving conditions.

Abstract: A method of making polymeric particulates wherein polymeric scrap material, virgin polymeric material and mixtures thereof are supplied to intermeshing extruder screws which are rotated to transport the polymeric material along their length and subject the polymeric material to solid state shear pulverization and in-situ polymer compatibilization, if two or more incompatible polymers are present. Uniform pulverized particulates are produced without addition of a compatibilizing agent. The pulverized particulates are directly melt processable (as powder feedstock) and surprisingly yield a substantially homogeneous light color product.

Abstract: A panel-forming system including a plurality of bulkheads and one or more extensions. A first group of the bulkheads are used to define the overall dimensions and shape of the panel, while a second group are used to define at least one aperture formed into the panel. The extensions are made up of a bulkhead-engaging portion and a recess portion that extends from the bulkhead-engaging portion. The aperture extensions are configured to allow various-shaped recesses to be formed in the panels adjacent the apertures. In accordance with 37 CFR 1.72(b), the purpose of this abstract is to enable the United States Patent and Trademark Office and the public generally to determine quickly from a cursory inspection the nature and gist of the technical disclosure. The abstract will not be used for interpreting the scope of the claims.

Abstract: A process for coextrusion-molding a multilayer article comprising coextruding at a selected coextuding temperature (i) a first outer polymer resin layer having a) a viscosity, b) a melting temperature, and c) a degradation temperature at the selected coextuding temperature, and (ii) a second inner polymer resin layer having a) a viscosity, b) a melting temperature, and c) a degradation temperature at the selected coextuding temperature, wherein the ratio of the outer polymer resin viscosity to the inner polymer resin viscosity at the coextuding temperature is less than or equal to about 1 and the coextuding temperature is above the melting temperature of the highest melting resin and below the degradation temperature of the lowest degrading resin to form a multilayer article.

Abstract: This method for the manufacture of hollow bodies which do not contaminate the products contained therein, consists of maintaining the heat of molding of a hollow body, forming a container having an embouchure and produced by molding a first thermoplastic synthetic resin, in which there is applied in the interior thereof, a set amount of a second thermoplastic synthetic resin having a melting point lower than the temperature of the hollow body due to the residual molding heat thereof, after which the second resin is rotary molded within the hollow body, which acts as a mold, until the second resin, after being melted by the residual heat, has solidified forming a lining applied over the entire inner surface of the hollow body and the entire inner periphery of the rim of the embouchure.

Abstract: Apparatus and method for molding a tire (110) with a radially expandable bead molding ring (252). When expanded, the bead molding ring has a circumferentially continuous radially outward-facing surface (259) for molding the bead. The bead molding ring comprises a plurality of segments (254, 256), half of the segments being first segments (254) that are complementary to, and circumferentially alternated with second segments (256). The first segments are wedge shaped, having circumferentially lateral faces (255) that converge towards the radially outward-facing bead molding surface of the bead molding ring, the first segment lateral faces being planar and oriented in the axial direction; and the second segments have lateral faces (257) that are complementary to the first segment lateral faces, such that radially outward movement of the first segments (254) causes radially outward movement of the second segments (256). Guide rods (260) restrict first and second segments to radial movement (310) only.

Abstract: A molding method for protective equipment includes seven steps. A first step is to prepare a mold consisting of an upper and a lower mold respectively provided with a mold hole. A second step is to heat the mold to a preset first temperature. A third step is to place a plastic plate and a foam member in the mold. A fourth step is to move the upper mold nearer to the lower mold, and then close up the upper mold on the lower mold in a preset time for the two materials to melt. A fifth step is to heat the mold to a second temperature higher than the first temperature so that the outer surface of the two materials may melt. A sixth step is to cool the mold to a preset temperature to let the two materials cool to form a shape. The seventh step is to open the mold and take out a finished product.

Abstract: Apparatus and method for molding a tire (110) with an expandable bead molding ring assembly (250) having a two-stage movement from a retracted and disengaged state, to a radially expanded state, to an expanded and engaged state for molding a tire bead (112b). The two-stage movement is accomplished using a simple assembly of easily manufactured parts, and is driven by a simple continuous downward (axially outward) movement (320) of a hub (209) of a mold press (220). A combination of annular elements with springs converts the hub movement to the desired two-stage movement of segments (254, 256) of a segmented bead molding ring (252). Frustraconical cam surfaces (258, 266) are used to divide axially directed forces (420a, 420b) from the mold press movement (320) into radial force components (410a, 410b) and axial force components (415a, 415b) for causing corresponding radial movements (310) and axial movements (315) during the two stage movement.

Abstract: It is to provide a method of manufacturing a rubber crawler which enhances a degree of freedom in the handling in a vulcanization-shaping of a crawler part and largely improves vulcanization shapability and operability and facilitates an arrangement of an auxiliary device or the like.

Abstract: A process for manufacturing a track formed from a circumferentially continuous belt made of elastomeric material and comprising an inner surface and an outer surface, the inner surface being provided with a plurality of drive blocks uniformly arranged on the circumference, the process comprising a step in which an inner mold (10) formed by first and second die-halves (11, 12) is assembled, the two die-halves being able to be moved relative to each other in the axial direction to come into contact with each other on a joint surface. The inner mold (10) comprises a radially external laying surface (100) provided with a plurality of uniformly spaced cavities (103) for molding the drive blocks, each cavity being delimited in the axial direction by two side walls (111, 121), the joint surface (13) of the two die-halves (11, 12) being axially closer to one side wall than to the other side wall. A device for stripping the track from the inner and outer molds is also disclosed.

Abstract: An injection-molding die, which comprises a movable die platen guided via crossbeams is provided, wherein an adjusting element is positively connected to each crossbeam and can be adjusted axially relative to the crossbeam via a central drive and the position of the die platen changes relative to the crossbeams. An apparatus and method is provided in which at least one of the adjusting elements can be locked against an axial movement and against rotation by means of a fixing device. The fixing device may be a piston element in a closure cover arranged on the movable die platen.

Abstract: Pore-free rubber articles are prepared by dip-molding in a dipping medium that includes a vulcanizing agent, then by immersing the dip former in a heated liquid bath that is chemically inert. A particularly effective liquid bath is molten inorganic salt. In addition, the tensile properties of an article of vulcanized rubber can be improved to an unusually effective degree by immersing the already vulcanized article in a solution of a vulcanizing agent to cause the rubber of the article to absorb or imbibe the vulcanizing agent from the solution, and then immersing the rubber and the imbibed vulcanizing agent in a heated liquid bath to increase the degree of vulcanization.

Abstract: The present invention provides a tubing assembly having a sidewall having a first layer. The first layer is fabricated from a first polymer blend comprising a first component of a material not thermally responsive to laser beam and selected from the group consisting of polyolefins, ethylene and lower alkyl acrylate copolymers, ethylene and lower alkyl substituted alkyl acrylate copolymers, ethylene vinyl acetate copolymers, polybutadienes, polyesters, polyamides, and styrene and hydrocarbon copolymers. A second component of the blend is a laser responsive material having low solubility in aqueous medium; and the blend being sufficiently thermally responsive to exposure to a laser beam having a wavelength within a range of wavelengths from about 700 nm to about 1500 nm to melt upon exposure to the laser beam for a short period of time. The assembly also has an end cap film covering the fluid outlet.

Abstract: A device comprises a male mold, a male prepress board slidably fastened with the male mold, a female mold, and a female prepress board slidably fastened with the female mold. The device is used to make an air sac in such a way that a cylindrical polyurethane body is first flattened out by the prepress boards, and that a closed air sac body is formed in the slide holes of the prepress boards, and further that the air sac is finally formed in the mold cavities of the male mold and the female mold.

Abstract: An apparatus and method for vacuum blow molding that utilizes vacuum force to hold, and thus, preclude movement of the parison within the mold cavity, whereupon highly-pressurized or compressed air is utilized to forcefully pierce the parison for expansion and conformation of the parison to the mold interior, thus affording consistent and uninterrupted production of the desired blow molded product without dependency upon blow pins or hollowed needles as utilized in prior art methods and machinery for blow molding processes.

Abstract: The invention relates to the field of processing starch. In particular, the invention relates to a process for extruding starch to obtain a starch product having a certain intrinsic viscosity when dissolved or dispersed in water, which process requires less specific mechanical energy input than conventional extrusions of starch.

Abstract: The invention relates to an air damper for mobile furniture parts, such as drawers or doors, consisting of a cylinder that is open at one end and a piston with seal that is movable in the longitudinal direction in this cylinder and that is connected to a ram. According to the invention, there is a small drilled hole provided in the outer wall of the cylinder near the closed end section of the cylinder.

Abstract: An insert disposed between two cooperating leaf springs. The insert includes a body including a stem having a plurality of radially extending ribs inserted into an aperture in a first leaf spring. The body includes a face which slidably engages a second leaf spring. The face includes a plurality of circular protrusions extending therefrom. A pin is inserted into a central bore formed by cooperating fingers that form the body, causing an outwardly extending radial retention force to be exerted onto the surface of the aperture in the first leaf spring.

Abstract: Disclosed is a fluid-tight vibration damping device including a first and a second mounting member elastically connected with each other by an elastic body interposed therebetween, a primary fluid chamber filled with a non-compressible fluid and partially defined by the elastic body and a movable rubber plate partially defining the primary fluid chamber by one of its opposite surfaces. An engaging member is disposed to be opposed to the other surfaces of the movable rubber plate with a spacing therebetween. The engaging member is adapted to be engaged with an engaging portion integrally formed with the movable rubber plate to restrict an amount of displacement of the movable rubber plate in directions toward and away from the interior of the primary fluid chamber.