JPH0710999Y2 - Grommet seal structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a grommet seal structure for covering a connecting portion between a jacket tube and a hole cover in a steering device of an automobile.

[Prior Art] In many cases, a steering system of an automobile adopts a tilt type structure that can ensure an optimal driving position according to the body shape of an occupant. The tilt type structure includes a so-called foot tilt type and a hand tilt type. There are two formulas. The former is
The lower end of the steering column is swingably connected to and supported by the hole cover, and the latter is configured so that the upper end of the steering column can be bent around a tilt hinge of a clamp that supports the upper end.

The foot tilt type steering device, as shown in FIG. 5 , is provided between the hole cover 1 and the end portion of the lower tube 2.
The grommet 3 including a rubber seal cover is interposed. The hole cover 1 is fixed to the dash plate 4, the lower tube 2 is axially contractibly fitted to the upper tube 5 to form a column jacket, and the column jacket is vertically attached to a clamp 7 via a distance bracket 6. It is swingably supported. The clamp 7 is provided with a long hole 8 capable of moving the distance bracket 6 in the vertical direction, and a tightening bolt 9 penetrating the long hole 8 and the distance bracket 6 is provided, and the tightening bolt 9 has a tilt lever. I am wearing 10. Therefore, when adjusting the tilt, the tilt lever 10 is rotated to release the tightening between the clamp 7 and the distance bracket 6, and the steering wheel 11 is moved in the desired direction up and down, whereby the column jacket is fixed to the vehicle body. It rotates about the shaft 13 of the bracket 12. Then, the steering wheel 11 is stopped at a desired position,
When the tilt lever 10 is rotated in the opposite direction, the tightening bolt 9 tightens the clamp 7 to the distance bracket 6, and the clamp 7 is fixed by frictional engagement between the two.

[Devise a problem to be solved point] However, according to the conventional foot tilt type steering device, the grommet 3, as shown in FIGS. 3 and 4, a unique shape, hole cover Groove 3f that fits into the end of 1 and fits and fixes the tightening ring 14
Between the fitting end portion 3a having the above-mentioned shape and the fitting end portion 3b fitted into the lower end portion of the lower tube 2, convex portions 3c and 3d which are diametrically opposed to each other are formed on the peripheral side wall portion in a substantially circular shape. Cylinder 15 and
It is composed of an oval cylindrical body 16 which is eccentrically overlapped with this, and has a groove 3e to be fitted into the end portion of the lower tube 2 and a fitting end portion 3b.
When the lower tube 2 swings largely at the time of tilt adjustment, the follow-up performance of the fitting end portion 3b is poor and the fitting end portion that is pressed against the outer peripheral surface of the lower tube 2 is engraved on the inner peripheral edge of the lower tube 2. 3b
Is lifted from the outer peripheral surface of the lower tube 2, and a gap is formed in the seal structure, which causes a problem of reducing the sealing effect.

Therefore, this invention has been made for the purpose of improving the seal structure of the grommet in the above conventional example.

[Means for Solving the Problems] In order to solve the above problems, the present invention has a circular cylindrical body having a fitting end portion for fitting a lower tube and a fitting end for fitting a hole cover. A grommet that is eccentric with an oval cylinder that forms a portion, and is integrated by being overlapped with each other. The grommet is pressed against the lower tube at the inner peripheral edge of the fitting end portion into which the lower tube is fitted. A ring having a substantially circular cross section is formed, and at the fitting end portion for fitting the hole cover, an annular protrusion is formed on the inner peripheral surface thereof, and the outer peripheral surface thereof is fixed by tightening with a tightening ring, and A bellows portion is formed at a connecting portion between a circular cylinder body having a fitting end portion for fitting the lower tube and an oval cylinder body having a fitting end portion for fitting a hole cover. It is a grommet structure.

[Operation] According to the present invention having the above configuration, a circular cylinder having a fitting end for fitting the lower tube and an oval cylinder having a fitting end for fitting the hole cover. Since the bellows portion is formed at the connecting portion with, the circular cylindrical body having the fitting end portion is displaced following the displacement of the lower tube.

Therefore, it is possible to increase the rigidity of the circular cylindrical body having the fitting end portion and prevent the fitting end portion from coming off when the lower tube is displaced.

Further, since an annular body having a substantially circular cross section which is pressed against the lower tube is formed on the inner peripheral edge of the fitting end portion for fitting the lower tube, even if the lower tube swings largely, the lower tube has a substantially circular cross section. Since the inner peripheral edge is in close contact with the outer peripheral surface of the lower tube and no gap is formed, the sealability is improved.

[Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings. First
FIG. 2 and FIG. 2 show a first embodiment of the present invention,
Which corresponds to the FIGS. 3 and 4. The grommet 3 shown in the figure is basically a circular cylinder 30 and an oval cylinder 31 which are eccentric and superposed on each other so as to be integrated, and a fitting end 32 for fitting the lower tube 2 therein. The inner peripheral edge 33 is formed in an annular shape having a substantially circular cross section, and the fitting end 32
At the connecting portion of the circular tubular body 30 and the oval tubular body 31 having
A bellows portion 34 having a wavy cross section is integrally formed.

The fitting end portion 35 into which the hole cover 1 is fitted is engraved with a groove portion 36 into which the tightening ring 14 is fitted, and a rib-like projection portion 37 is formed in an annular shape on the inner circumferential surface, Stopper part 38 for stopping the edge of the hole cover 1
Are formed. And the peripheral side wall portion 3 of both fitting end portions 32, 35
9 is formed to be substantially flush and does not have a conventional protrusion protruding outward.

Therefore, according to the grommet 3 in the above-described embodiment, when the lower tube 2 swings in the vertical direction when the tilt is set, the inner peripheral edge 33 of the fitting end portion 32 is constantly in pressure contact with the outer peripheral surface of the lower tube 2, Lower tube 2 through the bellows 34
And the fitting end 35 into which the hole cover 1 is fitted has the protrusion 37 on the inner peripheral surface thereof pressed against the hole cover 1 to secure the sealing property of the grommet 3. .

[Effects of the Invention] According to the invention described above, a circular cylinder having a fitting end for fitting a lower tube and an oval cylinder having a fitting end for fitting a hole cover. Since the bellows portion is formed at the connecting portion with the body, the circular cylindrical body having the fitting end portion is displaced following the displacement of the lower tube. Therefore, it is possible to increase the rigidity of the circular cylindrical body having the fitting end portion and prevent the fitting end portion from coming off when the lower tube is displaced. Further, since an annular body having a substantially circular cross section which is pressed against the lower tube is formed on the inner peripheral edge of the fitting end portion for fitting the lower tube, even if the lower tube swings largely, the lower tube has a substantially circular cross section. Since the inner peripheral edge is in close contact with the outer peripheral surface of the lower tube and no gap is formed, the sealing performance can be improved.

[Brief description of drawings]

Perspective view of Figure 1 embodiment of this invention, Figure 2 is a vertical sectional side view thereof, FIG. 3 is a perspective view of a conventional example, FIG. 4 is a vertical sectional side view thereof, Fig. 5 feet tilt type It is an explanatory view of a steering device. 1 …… Hall cover, 2 …… Lower tube, 3 …… Grommet, 30,31 …… Cylinder body, 32,35 …… Fitting end, 33 …… Inner peripheral edge, 34 …… Bellow part, 36 …… Groove, 37 ... Protrusion, 38 ...
… Stopper part, 39 …… peripheral side wall part.

Claims (1)

[Scope of utility model registration request] 1. A circular cylinder body having a fitting end portion for fitting a lower tube and an oval cylinder body having a fitting end portion for fitting a hole cover are eccentric to each other and overlap each other. A grommet which is integrally formed together, and an annular body having a substantially circular cross section which is pressed against the lower tube is formed on an inner peripheral edge of a fitting end portion for fitting the lower tube, and the hole cover is fitted therein. The fitting end has a circular projection having an inner peripheral surface formed with an annular projection, the outer peripheral surface of which is tightened and fixed by a tightening ring, and a fitting end for fitting the lower tube is formed. A grommet seal structure, characterized in that a bellows portion is formed at a joint portion between a cylindrical body and an oval cylindrical body having a fitting end portion for fitting a hole cover.