JPH04307181A - Seal structure - Google Patents

Abstract

PURPOSE:To provide a seal structure capable of decreasing a load for locking a pair of members with a seal body interposed, and of exhibiting sufficient sealing performance for a long time. CONSTITUTION:Between a top cowl 26 and a bottom cowl 22, a seal body 24 composed of a base 38, a side lip 40, and a main lip 42 is interposed. About the lower half of a ring 54 of the main lip 42, which requires little strength, and a projected piece 56 are formed by sponge rubber 54A, and the other parts of the seal body 24 are formed by soiled rubber 54B.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal structure for press-contacting a pair of members through a seal body, and more particularly to improvements in the material of the seal body.

0002

2. Description of the Related Art As an example of a conventional seal structure, a seal structure for an outboard motor is known, for example, as described in Japanese Patent Laid-Open No. 2-292575. In this conventional example, a seal body is interposed between a top cowl that covers the upper part of the engine and a bottom cowl that covers the lower part of the engine. By having a configuration including a protruding piece that extends from the bottom cowl, the pressing force when attaching the top cowl to the bottom cowl is reduced as much as possible. In order to improve the sealing performance of the outboard motor and to provide sufficient strength to prevent the occurrence of cracks, etc., the seal body is made of hard solid rubber.

0003

[Problems to be Solved by the Invention] However, when the seal body is made of solid rubber, the load required to lock the bottom cowl and top cowl when the cowling is attached, that is, the locking load, is still high, making it difficult to lock the cowl. There was a problem. Furthermore, when solid rubber is used for a long period of time under a high locking load, permanent deformation occurs, resulting in a problem in that the sealing function deteriorates. Therefore, in order to reduce the locking load, it is conceivable to form the seal body with soft rubber, but doing so causes a decrease in sealing performance and a decrease in the durability of the seal body.

[0004] Therefore, the present invention provides a seal structure that requires a low load to lock a pair of members with a seal body interposed therebetween, and that can provide sufficient sealing performance over a long period of time. Its purpose is to provide.

[0005]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a seal structure in which a pair of members are brought into pressure contact through a seal body, in which a part of the seal body is formed of soft rubber. , the other parts are made of hard rubber.

[0006]

[Function] By forming one part with soft rubber and the other part with hard rubber, the sealing performance is maintained while ensuring the strength required for the sealing body, and the reaction of the sealing body during sealing is achieved. This reduces the force and further reduces the amount of permanent deformation of the entire seal body. Therefore, a seal structure having such a seal body can reduce the locking load and exhibit sufficient sealing performance over a long period of time.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to the accompanying drawings. FIG. 2 is a cutaway view showing the main parts of an outboard motor cowling equipped with an embodiment of the seal structure. Reference numeral 10 denotes an outboard motor, and its propulsion unit 12 is attached to the stern plate 14 of the hull via a clamp bracket 16 and a swivel bracket 18 so as to be rotatable vertically and horizontally. Reference numeral 13 indicates a tilt pin that supports the swivel bracket 18 so as to be able to rotate up and down with respect to the clamp bracket 16, and 15 indicates a steering bracket. An engine 20 is located at the top of the propulsion unit 12, and this engine 20 connects the bottom cowl 22 and the bottom cowl 2.
The top cowl 2 is attached to the top cowl 2 via the seal body 24.
6. In this embodiment, a recess 28 is provided at the front surface of the bottom cowl 22, and a clamp lever 30 that is operated when releasing the engagement/disengagement mechanism between the bottom cowl 22 and the top cowl 26 is disposed within the recess 28. . The outer surface shape of the clamp lever 30 is made substantially flush with the outer peripheral shape of the bottom cowl 22, and the abutting portions of both cowls are also made substantially flush with each other to improve the design.

Reference numeral 32 denotes a so-called latch-and-strike type engagement/disengagement mechanism provided at the front and rear portions of the cowling, respectively.The top cowl 26 is attached to the bottom cowl 22, and the front and rear portions of the top surface of the top cowl 26 are manually operated. By simply holding the top cowl down and applying a locking load, the approximately L-shaped hook 34 hanging down from the top cowl 26 is locked to the latch-type locking member of the bottom cowl 22, and when releasing this lock, By rotating the clamp lever 30, the locking member elastically opens the hook 34. Since this engaging/disengaging mechanism 32 is not an essential part of the present invention, a detailed explanation thereof will be omitted. The front and rear locking mechanisms are connected to each other via a wire 36 so that the rear locking mechanism 32 is also operated to release the hook 34 when the clamp lever 30 is operated.

FIG. 1 is a detailed view of the seal body of FIG. 2. The seal body 24 is mainly composed of a substantially U-shaped base 38, a side lip 40, and a main lip 42, and the base 38 is a seal that protrudes downward from the lower inner edge of the top cowl 26. The mounting rib 44 is fitted and held. Reference numeral 46 is formed on the U-shaped inner surface of the base portion 38;
This is a weather strip that presses against the seal portion mounting rib 44 while being bent. In addition, the code|symbol 62 is a core metal.

A rib 48 is also formed along the outermost edge of the upper edge of the bottom cowl 22 to protrude upward, and the side lip 40 comes into pressure contact with the upper edge of the rib 48. The side lip 40 is formed thin and has a hanging part 50 that hangs down integrally from the base 38 at a position that projects slightly outward from the outer surface position of the top cowl 26, and a hanging part 50 that curves inward from the lower end of the hanging part 50. The horizontal portion 52 is formed into a generally L-shaped cross section as a whole.

The main lip 42 is approximately U of the base portion 38.
A ring part 54 extends integrally from the lower part of the shape and has a substantially pentagonal cross section with the lower part of the base part 38 as one side.
and a projection piece 56 formed by integrally extending one side of a pentagon obliquely downward from the lower end of the ring part 54. This main lip 42 is connected to a photo seal surface 70 inside the rib 48 of the bottom cowl 22.
is located opposite. This main lip 42 is the part that exhibits the most important waterproof performance of the seal body 24, and its total length in the vertical direction is the total length of the ring part 54 and the protruding piece 56. The reaction force at the time is reduced.

The substantially lower half of the ring portion 54 and the protruding portion of the seal body 24, which do not require relatively high strength, are made of sponge (foam) rubber 54A, which is soft rubber. On the other hand, approximately the upper half of the ring portion 54 is formed of solid rubber, which is hard rubber, integral with the base portion 38 and the side lip 40, since the portion connected to the base portion 38 requires strength to prevent cracks, etc. has been done. In order to form such a synthetic seal structure of solid rubber and sponge rubber, it is possible to fill a portion corresponding to approximately the lower half of the ring portion 54 with a resin containing a foaming agent and mold the ring portion 54 integrally.

Ring portion 54 and protrusion piece 5 of the seal body
6 is made of soft sponge rubber, so
It easily bends due to compressive force and bending stress when the cowling is locked, and can reduce the reaction force when the cowling is locked, and thus the locking load. Furthermore, sponge rubber has better elastic deformability than solid rubber, and can reduce permanent deformation caused by compressive force during sealing. On the other hand, since the approximately upper half of the seal body 24 on the top cowl side, which requires strength, is formed of solid rubber, even if the approximately lower half of the seal body, on the bottom cowl side, is formed of sponge rubber, the seal It is possible to maintain the necessary sealing performance while ensuring the necessary durability of the body. With the above configuration, the locking load when locking the top cowl 26 to the bottom cowl 22 can be reduced, and sufficient sealing performance can be exhibited over a long period of time.

The sealing body is made of butadiene polymer, butadiene and styrene copolymer, butadiene and acrylonitrile polymer, chloroprene polymer, isoprene polymer, isobutylene and isobrene copolymer, ethylene and propylene copolymer. It can be formed from a polymer or synthetic rubber such as a copolymer of ethylene, propylene, dicyclopentadiene, etc. The hardness of the portion of the seal body made of solid rubber that requires strength is preferably in the range of 60 to 80 Hs, particularly 7.
It is 0Hs. In addition, the parts of the seal body made of sponge rubber that do not require strength have a hardness of 15 to 20H.
The range is preferably 20Hs, particularly 20Hs. In addition, the density of the sponge rubber part is 0.6 to 0.7 g/
The specific gravity of the solid rubber portion is preferably within the range of 0.8 to 0.9 g/cm3.

[0015] Furthermore, as for the properties of the synthetic rubber, it is desirable that it has durability such as aging resistance and ozone resistance. Furthermore, it is desirable to use a thermosetting synthetic rubber (for example, urethane rubber) that has little temperature dependence, that is, is not thermoplastic. The reason why it is desirable to use synthetic rubber with less temperature dependence is because if the rubber hardness is high at low temperatures, the locking load of the cowling will be high, and this is to ensure that the locking load is low even in low-temperature regions.

In the above embodiment, both the hard part and the soft part of the seal body are made of the same material, and the soft part is made of sponge rubber to reduce the hardness. It may also be used with other synthetic rubber materials. Further, in this embodiment, the seal body of a cowling of an outboard motor has been described, but the present invention is not limited to this, and the present invention can be applied to any seal structure. Further, in this embodiment, the portion of the seal body that does not require relatively strength and can be formed of soft rubber is approximately the lower half of the ring portion 54, but these portions may be determined as appropriate depending on the type of the seal body. However, there are no particular limitations. Furthermore, the soft portion may be formed not only by using a foaming agent but also by changing the molding temperature.

[0017]

[Effects of the Invention] As explained above, according to the seal structure of the present invention, the parts of the seal body that do not require strength are made of soft rubber, so the locking load can be low and sufficient. It can exhibit sealing properties for a long period of time.

[0018]

[Brief explanation of drawings]

FIG. 1 is a detailed view of a seal body according to an embodiment of the seal structure of the present invention.

FIG. 2 is an overall view of the outboard motor equipped with the seal body shown in FIG. 1.

[Explanation of symbols]

10 Outboard motor 12 Propulsion unit 20 Engine 24 Seal body 38 Base of seal body 40 Side lip of seal body 42 Main lip of seal body 54 Ring part of seal body 56 Seal body protrusion piece

Claims (1)

[Claims] 1. A seal structure in which a pair of members are pressed into contact with each other through a seal body, wherein a part of the seal body is made of soft rubber and the other part is made of hard rubber.