JP2752299B2 - Seal ring - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal ring for preventing oil and dust from entering.

[0002]

2. Description of the Related Art As a seal ring for an annular gap formed between two members in the form of a rotating body which are relatively slid in the axial direction, for example, a shaft member for sealing between a shaft member and a cylindrical member is used. An externally fitted seal structure that externally fits and locks into a cylindrical member, and an internally fitted seal structure that internally fits and locks into a cylindrical member to seal between the shaft member and the cylindrical member are known as general types. .

[0003]

Therefore, when the seal rings having the above two structures are used in an apparatus, an outer seal structure and an inner seal structure are required. However, in this case, each seal ring is created as a dedicated part, and there are disadvantages in terms of mold cost, part cost, and management thereof. Therefore, when the seal diameter is not much different, two types of seal rings are set. It seems uneconomic to do so and there is room for improvement.
An object of the present invention is to reduce the cost by using a single seal ring for both the outer fitting seal structure and the inner fitting seal structure.

[0004]

In order to achieve the above-mentioned object, the present invention provides a seal ring for an annular gap formed between two members in the form of a rotating body which is slid relative to each other in the axial direction. An outer peripheral seal portion for a seal function on the inner peripheral surface of the member and an inner peripheral seal portion for a seal function on the outer peripheral surface of the inner fitting side member form a seal main body. It is characterized in that a fitting portion for attachment to the end is formed so as to protrude in the axial direction.

[0005]

According to the above-mentioned characteristic structure, the seal ring is constructed in such a state that both the externally fitted seal structure and the internally fitted seal structure can be applied. For example, as shown in FIG. Fixed pulley piece 4A and movable pulley piece 4
A seal ring R attached to the end of the movable pulley piece 4B to seal the gap with the movable pulley piece 5B and the end of the movable pulley piece 5B to seal the gap between the movable pulley piece 5B and the rotary cylinder shaft 11 in the passive pulley 5. It becomes possible to use it by attaching it. That is, as shown in FIG.
With the idea that either one of the o and the inner peripheral seal part ri is used as an actual use surface and the other side is left idle, a single seal ring R can exert two different sealing functions under different conditions. Became.

[0006]

As a result, it is possible to reduce the cost of the mold due to the common use of the parts, thereby reducing the cost as the unit cost of the parts. Further, since the seal rings used for different parts can be covered by a single part, there is no erroneous combination. There is an advantage.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings when applied to a belt continuously variable transmission of a rice transplanter. FIG. 1 shows a belt continuously variable transmission A extending over an engine output shaft 7 and a transmission input shaft 8, wherein 4 is a split driving pulley composed of a fixed pulley piece 4A and a movable pulley piece 4B, and 5 is a fixed pulley piece 5A. A passive split pulley composed of a movable pulley piece 5B, a belt 6, a clutch 7, and an interlocking shift mechanism 16 for slidingly adjusting the movable pulley pieces 4B, 5B as a set. More specifically, the drive split pulley 4 has a fixed pulley piece 4A externally fitted integrally with the drive side base shaft 9 externally fitted to the engine output shaft 7 in a rotating state by a key connection, and the movable pulley piece 4B The movable pulley piece 4 </ b> B is slidably and externally fitted, and the movable pulley piece 4 </ b> B is slid by the driving cam mechanism 10 fitted to the driving base shaft 9 outside the spline. The passive split pulley 5 has a fixed pulley piece 5A spline-fitted on a passive-side base shaft 11 fitted externally to the transmission input shaft 8 so as to rotate integrally therewith, and a movable pulley piece 5B is slidably fitted on the passive input shaft 8 so as to slide freely. In this structure, the movable pulley piece 5B is slid by the passive cam mechanism 12 fitted to the base shaft 11 via a key connection. In the drive split pulley 4, each movable pulley 4A is located between the fixed pulley piece 4A and the movable pulley piece 4B, and in the passive split pulley 5, between the movable pulley piece 5B and the passive base shaft 11.
A seal ring R is provided to prevent foreign matter such as dust from entering the gaps between the base shafts 9 and 11 and the base shafts 9 and 11. Next, the seal structure will be described.

[0008] As shown in FIG.
And a seal main body Rh formed by an inner peripheral seal portion ri for a seal function with respect to the outer peripheral surface of the inner fitting side member,
A fitting portion Rt protruding in the axial direction on the seal body Rh.
To form a seal ring R. Fitting part R
At t, a fitting peripheral groove m is formed. Drive split pulley 4
Then, as shown in FIG. 2, the seal ring R is mounted on the left end portion of the movable pulley piece 4B in a state where the seal ring R is prevented from being removed by fitting into the peripheral groove m, and the inner peripheral surface 13 of the fixed pulley piece 4A is provided. An outer fitting seal structure is adopted so that a sealing function is generated by sliding contact between the outer peripheral seal portion ro. In the passive split pulley 5, as shown in FIG.
The seal ring R is attached to the right end portion of the base shaft 11 in a state where the seal ring R is prevented from coming off by fitting with the fitting peripheral groove m, and the passive-side base shaft 11
The inner fitting seal structure is adopted so that the sealing function is generated by the sliding contact between the outer peripheral surface 11a and the inner peripheral sealing portion ri. In the drive split pulley 4, the movable pulley piece 4
At the base of B, a contact surface 14 is formed for determining the state in which the winding diameter of the belt 6 is maximized by contact with the fixed pulley piece 4A.

[Other Embodiment] In order to mount the movable pulley pieces 4B and 5B by press fitting, the seal ring R may have a fitting portion Rt having a simple protruding shape. In this case, it is convenient to embed the reinforcing fitting.

[0010] In the claims, reference numerals are provided for convenience of comparison with the drawings, but the present invention is not limited to the configuration of the attached drawings by the entry.

[Brief description of the drawings]

FIG. 1 is a structural diagram showing a belt continuously variable transmission of a rice transplanter.

FIG. 2 is a cross-sectional view of a drive split pulley showing an externally fitted seal structure.

FIG. 3 is a cross-sectional view of a passive split pulley part showing an inner fitting seal structure.

FIG. 4 is a sectional view showing the shape of a seal ring.

[Explanation of symbols]

 Rh seal body ro outer seal part ri inner seal part Rt fitting part

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F16J 15/16 F16H 9/12 F16H 55/56

Claims (1)

(57) [Claims] 1. A seal ring for an annular gap formed between two members in the form of a rotator that is slid relative to each other in an axial direction, and an outer peripheral seal portion for a seal function on an inner peripheral surface of an outer fitting side member. (Ro) and an inner peripheral sealing portion (ri) for a sealing function with respect to the outer peripheral surface of the inner fitting side member, form a seal main body (Rh), and attach the seal main body (Rh) to the sliding member end. A seal ring having a fitting portion (Rt) to be mounted on the device, formed so as to protrude in the axial direction.