JPH06117594A - Drain valve structure - Google Patents

Abstract

PURPOSE:To provide a drain valve structure made of resin, which can be fastened by an optimum torque only in a manual operation, and which is hard to be loosened even through vibration acts thereon. CONSTITUTION:A drain valve structure comprises a resin cylindrical part 12 having a drain hole, and a resin valve part 5 having a shank part including a seal ring 53 and a head part 52 and adapted to be threadedly engaged in the cylindrical part 12 so as to make the seal ring 53 into pressure contact with the inner peripheral surface thereof in order to seal between a main passage and a drain hole. A convex part 56 and a concave part 14 adapted to be engaged with each other are formed respectively on the opening end face of the cylindrical part 12 and the opening end face of the head part 52, which are opposed to each other. Since a large fastening force is required when the surface other than the concave part overrides the convex part 56, the condition in which the concave part is engaged with the convex part is distinguishable. Accordingly, the fastening force may be controlled by feeling. Further, since the loosening thereof requires the same force, thereby it is hard to be loosened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a drain valve provided in a flow path of engine cooling water of an automobile,
Specifically, it relates to a resin valve structure.

[0002]

2. Description of the Related Art A water drain valve is provided in a flow path of engine cooling water of an automobile so that the cooling water can be discharged from the flow path. Conventionally, the water drain valve was often provided in the lower part of the radiator, but when the distance between the radiator and the engine is large, it is necessary to add a water drain valve to the cooling water circulation circuit on the engine side. Also,
Due to the complicated engine control in recent years, the branching of the hose is often used.

However, the branch portion is usually formed by fixing a rubber hose to a metal pipe with a metal clip, and the water drain valve portion is also composed of a metal main body and a metal water drain valve. There was a demand for improvement in terms of manufacturing and man-hours. Therefore, it is considered that the branch part is made of resin and the drain valve is made of resin to reduce the weight, and the assembling is integrated into the assembling workability and the assy shape accuracy.

[0004]

By the way, a drain valve is generally attached by screwing, and the drain hole is closed by tightening the screw, and the drain hole is opened by loosening the screw to enable draining. There is. However, even with a water drain valve that is tightened, there is a concern that the screw may loosen and water may leak due to vibration. Therefore, it is necessary to tighten strongly, but in the case of a resin drain valve,
Tightening the screw more than necessary may damage the screw. Therefore, it is necessary to tighten with the optimum torque, but it is difficult to tighten with the optimum torque only by manual work.

The present invention has been made in view of the above circumstances, and in a water drain valve structure made of resin, it can be tightened with an optimum torque only by manual work, and is loosened even when vibration is applied. The purpose is to make the structure difficult.

[0006]

The water drainage valve structure of the present invention for solving the above problems has a drainage penetrating a peripheral wall having a tubular shape branched from a main flow path and having an internal thread formed at one end thereof. A resin cylindrical portion having a hole, a shaft portion having a seal ring at one end and a male screw formed at the other end side, and a head portion having a diameter larger than that of the shaft portion formed at the other end of the shaft portion, It is composed of a resin valve part that seals between the main flow path and the drainage hole by being screwed into the opening of the cylinder part and the seal ring is pressed against the inner peripheral surface of the cylinder part. The surface facing the open end surface of the end surface and the head portion is characterized by having a concave portion and a convex portion that engage with each other. If the convex portions are intermittently formed on the concentric circles of the opposing surfaces, the convex portions become concave portions and engage with each other.

[0007]

In the water drainage valve structure of the present invention, when the valve portion is tightened to the tubular portion, the convex portion provided on one of the surfaces facing the opening end surface of the tubular portion and the opening end surface of the head portion is the other surface. Abut. When tightened further, a large tightening force is required when the convex portion and the surface other than the other concave portion are in contact with each other, and when the concave portion and the convex portion are engaged, they are loosened to some extent. When it is further tightened, a large tightening force is required when the surface other than the concave portion crosses the convex portion, and the person who is tightening can clearly distinguish the state in which the concave portion and the convex portion are engaged.

Therefore, with the concave portion and the convex portion engaged,
By designing the seal ring to be in a sealed state by pressing against the inner peripheral surface of the tubular part when tightened until a feeling of being tightened to some extent is obtained,
It can be securely tightened and is prevented from being excessively tightened. In addition, in order to loosen the engaged state of the concave portion and the convex portion, the same large force as when the surface other than the concave portion crosses the convex portion is required during tightening, so that it is prevented from loosening due to vibration or the like. .

[0009]

EXAMPLES The present invention will be specifically described below with reference to examples. Figure 1
2 shows a water drain valve structure of one embodiment of the present invention. This drainage valve structure is composed of a branch pipe 1 made of fiber reinforced nylon, two rubber hoses 2, a covering portion 3 and a flange portion 4 made of fiber reinforced nylon, and a valve 5 made of fiber reinforced nylon. Has been done.

As shown in FIG. 4, the branch pipe 1 is composed of a pair of branch cylinders 10 and 11 which are respectively inserted into the hose 2, and a cylinder portion 12 which communicates with the branch cylinder 10 and the branch cylinder 11. The cylindrical portion 12 has a drain hole 13 penetrating the peripheral wall thereof, and four projections 14 are formed on the tip end surface of the cylindrical portion 12. A female screw 15 is formed on the inner peripheral surface up to the upper part of the water drain hole 13, and a tapered surface 16 having a gradually decreasing diameter is formed on the lower part of the water drain hole 13. This tube 1
A valve 5 is screwed into the valve 2, as shown in FIG.

A plurality of ring-shaped projections 17 for preventing the hose from coming off are formed on the outer peripheral surfaces of the branch cylinders 10 and 11, respectively, and the hose insertion positioning is performed at the ends of the branch cylinders 10 and 11 opposite to the openings. Each of the collars 18 for use is formed. The hose 2 is a bypass hose, and the branch tubes 10 and 1
1 is inserted respectively.

The covering portion 3 covers the end portion of the hose 2 inserted through the branch cylinders 10 and 11, covers the outer peripheral surface of the cylinder portion 12, and the integrally formed flange portion 4 is opposite to the branch cylinder 10. Extends to. This coating 3 is formed by injection molding nylon reinforced with glass fiber,
The hose 2 is sandwiched between the branch cylinders 10 and 11 by the injection pressure during molding and the contraction during cooling, and the hose 2 is firmly fastened.

The flange portion 4 is plate-shaped and has a bolt hole 40 into which a mounting bolt is inserted. A metal ring 41 for reinforcement is integrally fixed to the bolt hole 40 by insert molding. In addition, the flange part 4
A rib 42 extending from a portion that covers the cylindrical portion 12 is formed on the inner surface of the outer peripheral portion of the outer peripheral portion of the outer peripheral portion to reinforce the flange portion 4. The valve 5 is shown in FIG.
3, the shaft portion 51 having the male screw 50 and the shaft portion 5
1 has a large-diameter head portion 52 formed at one end thereof, and a rubber seal ring 53 is held at the other end of the shaft portion 51. In addition, a grip portion 54 for gripping with a finger is provided on the upper surface of the head 52.
4 are formed on the lower surface 55, as shown in FIG.

The water drain valve structure was manufactured as follows. First, the branch pipe 1 is formed by injection molding, and the hoses 2 are inserted into the branch cylinders 10 and 11, respectively.
The insertion depth is a position where the end surface of the hose 2 is in contact with the collar portion 18. Next, the branch pipe 1 having the hose 2 inserted therein is arranged in the split mold, and the metal ring 41 is arranged at a predetermined position to integrally form the covering portion 3 and the flange portion 4 by injection molding. The molten resin filled in the cavity is cooled and solidified while compressing the end portion of the hose 2 by injection pressure, and the end portion of the hose 2 is strongly pressed against the surfaces of the branch cylinders 10 and 11 by the covering portion 3 along with contraction due to cooling. And firmly conclude.

The valve 5 is separately formed by injection molding. In this drainage valve structure, the valve 5 has the tubular portion 1.
It is screwed to 2. At this time, if the lower surface 55 of the head portion 52 abuts on the tip of the convex portion 14 during screwing and is further tightened,
When the convex portion 14 and the lower surface 55 are in contact with each other, a large tightening force is required, and when the concave portion 56 and the convex portion 14 are engaged with each other, they are loose to some extent. When it is further tightened, the surfaces of the lower surface 55 other than the concave portions 56 become convex portions 14.
A large tightening force is required when the force exceeds, and the difference between the state in which the concave portion 56 and the convex portion 14 are engaged can be clearly distinguished for the person who is tightening.

At this time, as the valve 5 is screwed, the seal ring 53 advances in the central hole of the cylindrical portion 12, and the tapered surface 1
6 gradually compresses and exerts a sealing property. Therefore, between the inside of the branch pipes 10 and 11 and the drain hole 13,
The seal ring 53 is pressed against the tapered surface 16 for sealing, and leakage from the water drain hole 13 is prevented. Also,
To loosen the state where the concave portion 56 and the convex portion 14 are engaged,
When tightening, the same large force as when the surface other than the concave portion 56 crosses the convex portion 14 is required, so that it is prevented from loosening due to vibration or the like.

In this embodiment, the convex portion 14 is provided on the tubular portion 12 and the concave portion 56 is provided on the valve 5, but conversely, if the concave portion is provided on the tubular portion 12 and the convex portion is provided on the valve 5, the same operation is performed.・ The effect is obtained. Further, the number of convex portions and concave portions is not limited to four and at least one convex portion may be provided, and the number of convex portions and concave portions may be different. Further, a plurality of concave portions are intermittently provided on the concentric circles on both opposing surfaces of the valve 5 and the cylindrical portion 12, and the convex portions are regarded as concave portions, and when the screws are screwed, the convex portions are opposite convex portions. It is also possible to make a judgment as to the tightening amount based on that feeling.

In the above embodiment, the taper surface 16 is formed in the center hole, and the seal ring 53 is pressed against the taper surface for sealing. However, the center hole has a large diameter portion and a small diameter portion. It is also possible to adopt a stepped hole provided with and seal the seal ring with the side surface when the seal ring is in the small diameter portion, and release the seal when retracting to the large diameter portion.

[0019]

In other words, according to the water drain valve structure of the present invention, since it is possible to manually tighten so as to obtain a substantially constant tightening torque, leakage is prevented and damage to the screw is prevented. Also, it is prevented from loosening due to vibration, etc., and water leakage is surely prevented.

Since it can be made of all resin,
Raw material cost and manufacturing cost can be reduced, and the product is lightweight and inexpensive.

[Brief description of drawings]

FIG. 1 is a perspective view of a water drain valve structure according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of the water drainage valve structure of one embodiment of the present invention before screwing the valve.

FIG. 3 is a cross-sectional view of the water drainage valve structure of the embodiment of the present invention after the valve is screwed.

FIG. 4 is a perspective view of a branch pipe used in an embodiment of the present invention.

[Explanation of symbols]

1: Branch pipe 2: Hose
3: Cover part 4: Flange part 5: Valve 1
2: Cylindrical part 13: Drain hole 14: Convex part 1
5: Female screw 16: Tapered surface 50: Male screw 5
1: Shaft part 52: Head part 53: Seal ring 5
6: recess

Claims (1)

[Claims] 1. A resin-made tubular portion having a tubular shape branched from a main flow passage, an opening having a female screw formed at one end, and a drainage hole penetrating the peripheral wall, and a seal ring at one end and the other end. A shaft portion having a male screw formed on the side thereof and a head portion formed at the other end of the shaft portion and having a diameter larger than that of the shaft portion. It is composed of a resin valve part that seals between the main flow path and the drain hole by being pressed against the inner peripheral surface of the cylindrical part, and the opening end surface of the cylindrical part and the opening of the head part. A water drainage valve structure characterized in that the surface facing the end face has a concave portion and a convex portion that engage with each other.