JPS6146297Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of industrial application] The present invention relates to a mounting structure for a breather plug provided to release the internal pressure to the outside when the internal pressure in the case of a gear transmission for a vehicle increases. ,
In particular, it relates to a mounting structure with a dust deflector.

[Conventional technology]

In general, the pressure inside the case of a gear transmission for a vehicle changes depending on the usage conditions, and when the pressure becomes high, there is a risk that the lubricating oil inside the case may leak to the outside from the seal. A breather plug is provided to release the air to the outside.
However, since this breather plug communicates between the inside and outside of the case, there was a problem in that muddy water or the like from the outside could conversely enter the inside and mix with the lubricating oil. This breather plug problem becomes particularly noticeable when vehicles such as automobiles are used under harsh conditions such as wetlands and wastelands.

FIG. 1 shows a conventional breather plug mounting structure, in which 1 is the entire breather plug, 2 is a case of a gear transmission, and an opening hole 3 is bored in the upper part of the case 2. The insertion part 4a of the plug body 4 is press-fitted, and the breather plug 1 is inserted into the case 2.
installed on. The upper part of the plug body 4 is a valve seat 4b, and a valve cover 5a is seated on this valve seat 4b, thereby forming a valve 5. A coil spring 7 is interposed between the valve lid 5a and the cap 6, and a constant spring pressure is always applied to the valve 5.
The valve 5 is designed to open when the internal pressure exceeds a certain level. Further, 4c is a flange of the plug body 4, and the insertion portion 4a of the plug body 4 is connected to the case 2.
It plays the role of positioning when it is press-fitted into the opening hole 3 of.

In this conventional breather plug mounting structure, when the pressure inside the case 2 becomes high, the valve 5 of the breather plug 1 is opened to release the internal pressure to the outside to normalize the pressure inside the case 2. However, when an automobile or the like is used under the above-mentioned severe conditions, the breather plug 1 is often covered with muddy water thrown by the wheels, or even when crossing a river. Such muddy water enters the inside of the cap 6 through the flange portion 4c of the plug body 4 and mixes with the lubricating oil. Also, depending on the mounting position height of the part, it may be submerged in water, but in this case, since the valve 5 is always closed, muddy water will not enter the case 2 when it is in a stationary state. However, when a car or the like is running, muddy water is transmitted through the cap 6 to the valve cover 5a.
The valve cover 5a is also rocked, and muddy water may enter the case 2 from the valve 5 during this rocking motion.

Therefore, in order to prevent muddy water from entering the case through the breather plug, a dust deflector that surrounds the outer periphery of the breather plug as disclosed in Japanese Patent Application Laid-Open No. 55-64091 is attached to the breather plug, or It is conceivable to attach it directly to the gear transmission case with bolts, etc.

[Problem that the invention attempts to solve]

However, in order to attach the dust deflector to the breather plug, the structure of the breather plug must be changed, and even when the dust deflector is attached directly to the gear transmission case with bolts, it is difficult to attach the dust deflector to the gear transmission case. Bolt holes must be drilled in the machine case for bolt attachment. As described above, both of the former means require changes to existing members, and the dust deflector cannot be easily attached.

Therefore, an object of the present invention is to enable a dust deflector that prevents muddy water, etc. from entering a gear transmission case through a breather plug to be easily installed without making any changes to existing members. It is in.

[Means for solving problems]

Therefore, the present invention is characterized in that the dust deflector can be attached using a breather plug.

Specifically, the breather plug mounting structure of the vehicle gear transmission of the present invention has a dust deflector,
It is formed into a cylindrical shape having a bottom portion, and a mounting hole is bored in the bottom portion into which the insertion portion of the breather plug is inserted and fitted. The bottom of the dust deflector is interposed and fixed between the flange of the breather plug and the gear transmission case.

[Effect]

As a result, the dust deflector is clamped and fixed between the gear transmission case by the flange of the breather plug, so the dust deflector can be installed without making any changes to the breather plug or the gear transmission case. This can be done at the same time as installing the breather plug to the gear transmission case.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a sectional view of an embodiment of the present invention, in which:
1 is the breather plug, 2 is the gear transmission case, 8
is a dust deflector.

The breather plug 1 is the same as the conventional one shown in FIG. It is composed of a cap 6, a coil spring 7, etc.

The dust deflector 8 has a mounting plate 8a at its lower end.
(bottom) is integrally formed into a cylindrical shape,
It surrounds the breather plug 1 and is arranged on its outer periphery. The height of the cylinder is somewhat higher than that of the breather plug 1, and the upper end of the cylinder is open in the front. A mounting hole into which the insertion portion 4a of the breather plug 1 is inserted and fitted is bored in the center of the mounting plate 8a. ,
By inserting and fitting the mounting hole of the mounting plate 8a into the insertion portion 4a of the breather plug 1 in advance, it is possible to fix it to the gear transmission case 2 at the same time. Furthermore, four small holes 9 are provided protruding from the lower part of the dust deflector 8 at 90° intervals.

As described above, in the present invention, a mounting hole is formed in the mounting plate 8a (bottom part) of the dust deflector 8 to insert and fit into the insertion part 4a of the breather plug 1, and the mounting hole is inserted into the upper opening hole 3 of the breather plug 1. When installing and fixing, insert and fit the mounting hole of the dust deflector 8 into the insertion part 4a of the breather plug 1 in advance,
Since the flange 4c of the breather plug 1 is interposed and fixed between the breather plug 1 and the upper opening hole 3, the dust deflector 8 can be attached and fixed to the gear transmission case 2 at the same time as the breather plug 1 is attached. Therefore, the dust deflector 8 can be easily arranged on the outer periphery of the breather plug 1 without making any changes to the breather plug 1 or the gear transmission case 2.

In addition, since the dust deflector 8 is arranged surrounding the breather plug 1, even if muddy water or the like is splashed, this dust deflector 8 protects the breather plug 1. Therefore, it is possible to prevent muddy water and the like from entering the gear transmission case 2.

Furthermore, even if the breather plug 1 is submerged in water, the amount of muddy water that causes vibrations to the cap 6 of the breather plug 1 is only the muddy water inside the dust deflector 8, so even when the cap 6 of the breather plug 1 is submerged in water, the amount of muddy water that causes vibrations is limited to the muddy water inside the dust deflector 8. 6 hardly swings, and muddy water or the like can be prevented from entering into the gear transmission case 2. In addition, dust deflector 8 may be damaged due to submersion in water.
After the muddy water that has entered inside the dust deflector 8 escapes from that state, it is naturally drained outside through a small hole 9 protruding from the lower part of the dust deflector 8.

Although a specific embodiment of the present invention has been described above, the present invention is not limited to this embodiment, and includes various embodiments within the scope of the claims for utility model registration. For example, instead of the pressurizing type breather plug having the valve 5, a conductive type breather plug not having the valve 5 may be used. Further, the dust deflector 8 may have a cylindrical shape with the upper end fully open, or may have a conical shape, or may have the upper end closed with a lid or the like. Further, the tubular shape may be a cylindrical shape or a rectangular shape such as a quadrangle or a hexagon.

[Effect of idea]

As described above, according to the present invention, the dust deflector, which is disposed surrounding the outer periphery of the breather plug, is interposed and fixed between the gear transmission case and the flange of the breather plug. Therefore, the dust deflector can be installed without making any changes to the breather plug or the gear transmission case, which facilitates commercialization and improves ease of assembly.

Furthermore, the dust deflector can be easily attached to conventional products that do not have a dust deflector.

Furthermore, compared to the case where the dust deflector is retrofitted by welding, etc., it does not require welding equipment, etc., so it can be handled with existing production equipment without changing production equipment, improving productivity. be able to.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing a conventional breather plug mounting structure, and FIG. 2 is a sectional view showing an embodiment of the present invention. 1... Breather plug, 2... Gear transmission case, 3... Upper opening hole, 4... Plug body, 4a
...insertion part, 4b...valve seat, 4c...flange,
5...Valve, 6...Cap, 7...Coil spring, 8...Dust deflector, 8a...Mounting plate (bottom), 9...Drain small hole.

Claims (1)

[Claims for Utility Model Registration] The gear transmission includes a breather plug having an insertion portion that is press-fitted into an upper opening hole of a gear transmission case, and a flange that locks the insertion portion from being inserted into the upper opening hole. Attached to the upper opening hole of the case,
In the breather plug mounting structure for a gear transmission for a vehicle, in which a dust deflector having a small drainage hole surrounding the breather plug is arranged and mounted on the outer periphery of the breather plug, the dust deflector is a cylinder having a bottom portion. A mounting hole is formed in the bottom of the dust deflector into which the insertion portion of the breather plug is inserted and fitted, and the bottom of the dust deflector is connected to the flange of the breather plug. A breather plug mounting structure for a gear transmission for a vehicle, characterized in that the breather plug is interposed and fixed between the gear transmission case and the gear transmission case.