JP2009062904A - Injector - Google Patents

Abstract

By simple means, movement of an adjusting screw after adjustment is prevented to prevent fluctuation or readjustment of the basic flow rate characteristic of the injector.
An electromagnetic valve 2 serving as a driving source is constituted by a yoke 21, a core 22, and a movable valve 23, and an injection nozzle having an injection port for injecting fuel with a valve provided at the tip of the movable valve 23 is disposed. The injection valve is formed, and a biasing force of the return spring is applied to the movable valve 23 to move the movable valve 23 against the biasing force of the return spring for a predetermined time, thereby opening the injection valve and the injection nozzle. In the injector having the adjusting screw 3 for adjusting the urging force of the return spring screwed into the shaft hole 24 of the core 22 from the opening 25 on the base end side, the gaseous fuel is injected into the engine from the shaft hole 24 of the core 22. By filling and solidifying the adhesive 5 from the opening 25 on the end side, the base end portion 31 exposed from the opening 25 of the adjusting screw 3 is covered to prevent loosening of the adjusting screw 3 and readjustment.
[Selection] Figure 1

Description

  The present invention relates to an injector for supplying gaseous fuel to an engine, and more particularly to an injector for injecting fuel from an injection nozzle by opening and closing a valve provided at the tip of a movable valve constituting the electromagnetic valve by an electromagnetic valve and a return spring. is there.

  Conventionally, for example, as disclosed in Japanese Patent Laid-Open Nos. 55-40391, 6-336916, 7-1551034, etc., the fuel injection amount to the engine is adjusted by an electromagnetic valve and a return spring. For example, as shown in FIG. 2, these injectors constitute an electromagnetic valve 2 serving as a drive source by a yoke 21, a core 22, and a movable valve 23. An injection nozzle having an injection port for injecting fuel with a valve at the tip is disposed to form an injection valve (not shown), and a biasing force of a return spring (not shown) to the movable valve 23 And the movable valve 23 is moved for a predetermined time against the urging force of the return spring to open the injection valve and inject gaseous fuel from the injection nozzle into the engine. .

  In the conventional injector, the biasing force of the return spring to the movable valve 23 is adjusted by the adjusting screw 3 screwed into the shaft hole 24 of the core 22 constituting the electromagnetic valve 2 from the opening 25 on the proximal end side. By doing so, the basic flow rate characteristics of the injector are adjusted.

  Therefore, if the adjusting screw 3 is operated, the basic flow characteristics of the injector will change and affect the engine characteristics, exhaust gas characteristics, etc. Therefore, readjustment of the adjusting screw 3 is prevented after delivery of the product. For example, as shown in Japanese Utility Model Publication No. 5-26300, the fixing nut 5 is screwed onto the protruding portion on the proximal end side of the adjusting screw 3 and an adhesive is applied thereto. The loosening of the adjusting screw 3 is prevented and the readjustment is prevented.

  However, in the fixing means for the adjusting screw 3 in the injector using the conventional fixing nut 5 together with the adhesive, the fixing nut 5 can be removed relatively easily. Since a very thin material is used, if it is removed, the thread is damaged due to the effect of the adhesive, and the removal becomes impossible.

In addition, as disclosed in, for example, Japanese Patent Laid-Open No. 10-9093, etc., means for preventing readjustment by covering the shaft hole of the core into which the adjustment screw is screwed is also adopted. There is a problem that the size increases and the price increases.
JP 55-40391 A Japanese Patent Laid-Open No. 6-336961 Japanese Unexamined Patent Publication No. 7-155104 Japanese Utility Model Publication No. 5-26300 JP-A-10-9093

  The present invention has been made in view of the above circumstances, and an inexpensive injector capable of preventing movement of the adjustment screw after adjustment and preventing fluctuation and readjustment of the basic flow rate characteristic of the injector by simple means. It is an issue to provide.

  In order to achieve the above object, the present invention provides an injection nozzle comprising a yoke, a core, and a movable valve serving as a drive source, and having an injection port for injecting fuel with a valve built into the tip of the movable valve. The injection valve is disposed, and a biasing force of a return spring is applied to the movable valve to move the movable valve for a predetermined time against the biasing force of the return spring, thereby opening the injection valve. An injector having an adjustment screw for injecting gaseous fuel from the injection nozzle into the engine and adjusting an urging force of the return spring screwed into the shaft hole of the core from a base end side opening. The adhesive screw is filled with an adhesive from the opening on the base end side and solidified to cover the base end portion exposed from the opening of the adjustment screw and prevent the adjustment screw from being loosened and prevented from being readjusted. And

  In the present invention, when the adhesive is an ultraviolet curable adhesive, not only can the productivity and work efficiency be improved in terms of handling and work processes, but the adhesive itself is completely cured. The adhesive is difficult to break because it has a certain degree of viscosity after being fixed, so the adhesive cannot be peeled off from the screw groove or operation groove of the adjusting screw, making re-adjustment extremely effective. It is possible to prevent.

  As described above, according to the present invention, the basic flow rate characteristic that has been set is maintained by preventing the adjustment screw that adjusts the pressing force to the movable valve of the injector from being loosened or readjusted with a simple and inexpensive means. be able to.

  Next, a preferred embodiment of the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows a preferred embodiment of the present invention. An injector 1 according to the present invention includes a yoke 21, a core 22, and a movable valve 23 as a driving source, similar to the conventional one shown in FIG. 2. An electromagnetic nozzle 2 is constructed, and an injection nozzle having an injection port for injecting fuel with a valve built in is provided at the tip of the movable valve 23 to form an injection valve (not shown) and the movable A biasing force of a return spring is applied to the valve 23 to move the movable valve 23 for a predetermined time against the biasing force of the return spring, thereby opening the injection valve and supplying gaseous fuel from the injection nozzle to the engine. By adjusting the urging force of the return spring to the movable valve 23 by the adjusting screw 3 screwed into the shaft hole 24 of the core 22 constituting the electromagnetic valve 2 from the opening 25 on the proximal end side. Injector basics It is to adjust the amount characteristics.

  In the present embodiment, in particular, the opening 25 on the proximal end side of the shaft hole 24 into which the adjustment screw 3 formed in the core 22 is screwed is at least the end face of the proximal end portion 31 of the adjustment screw 3 screwed. For example, an acrylic resin which is formed longer than the operation surface 41 formed in the base end direction and is filled and solidified in the base end portion 31 of the adjusting screw 3 exposed from the opening 25 on the base end side in the shaft hole 24. And an ultraviolet curable adhesive 5 such as epoxy resin.

  Therefore, since the base end portion 31 of the adjusting screw 3 is fixed to the shaft hole 24 at a predetermined screwing position by the solidified adhesive 5, there is no fear of loosening and it is difficult to readjust. Further, since the adjusting screw 3 is fixed by the ultraviolet curable adhesive 5 that cures with the predetermined viscosity, it is difficult to peel off the adjusting screw 3 even if the adhesive is broken. Cannot readjust.

  In the present embodiment, the adjusting screw 3 is screwed into the shaft hole 24 formed in the core 22 as described above and adjusted to a position where the basic flow characteristics of the injector can be obtained. It is adjusted by a simple operation such as filling the ultraviolet curable adhesive 5 having fluidity before curing from the opening 25 on the base end side and irradiating the ultraviolet ray generation lamp for a predetermined time to cure to a predetermined hardness. Since the screw 3 can be fixed, the operation is extremely simple and reliable. Further, the adhesive 5 alone does not require any extra parts, and the procurement and management of parts are unnecessary, which is economical.

  In this embodiment, since the UV curable adhesive that exhibits a certain viscosity after curing is used as the adhesive, the above-described excellent actions and effects are exhibited. However, the adhesive 5 is particularly UV curable. It is not limited to adhesives.

It is the perspective view which fractured | ruptured a part which shows embodiment of this invention, (a) is a general view, (b) is an enlarged view of the principal part. It is the perspective view which fractured | ruptured a part which shows a prior art example, (a) is a general view, (b) is an enlarged view of the principal part.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Injector, 2 Solenoid valve, 3 Adjustment screw, 5 Adhesive, 21 Yoke, 22 Core, 23 Movable valve, 25 Opening, 31 Base end part

Claims (2)

  The yoke, the core, and the movable valve constitute an electromagnetic valve serving as a drive source, and an injection nozzle having an injection port for injecting fuel with the valve built in is arranged at the tip of the movable valve to form the injection valve. In addition, a biasing force of a return spring is applied to the movable valve, and the movable valve is moved for a predetermined time against the biasing force of the return spring, thereby opening the injection valve and supplying gaseous fuel from the injection nozzle to the engine. In an injector having an adjusting screw for adjusting the biasing force of the return spring screwed into the shaft hole of the core and screwed from the opening on the base end side, an adhesive is applied to the shaft hole of the core from the opening on the base end side. An injector characterized in that, by filling and solidifying, the base end portion exposed from the opening of the adjustment screw is covered to prevent loosening and readjustment of the adjustment screw. 2. The fuel injection valve according to claim 1, wherein the adhesive is an ultraviolet curable adhesive.

Images