Mechanical seal device

Abstract

A mechanical seal device comprising a stationary side sliding ring (10), a rotating side sliding ring (20) capable of rotating and sliding in firm contact with the stationary side sliding ring (10), and an O-ring (30) interposed between the inner hole of the rotating side sliding ring (20) and a rotating shaft (200). The mechanical seal device further includes an annular ring member (60a) having a gas permeability lower than that of the O-ring (30). The ring member (60a) is installed in the inner hole of the rotating side sliding ring (20) so as to be adjacent to the O-ring (30) on the atmosphere side, and fulfills the requirement of the following conditional expression (1). In the conditional expression (1), (D1) is the diameter of the rotating shaft (200), (D2) is the inner diameter of the ring member (60a), and (D3) is the inner diameter of a portion of the inner hole of the rotating side sliding ring (20), which portion is located closer to the atmosphere side than the ring member (60a). D1 < D2 < D3 ... Expression (1).

Description

technical field [0001] The invention relates to a high-pressure mechanical seal device that seals around the rotating shaft, especially relates to 2 Refrigerant CO enclosed in air-conditioning compressors, etc., where the gas is used as the refrigerant 2 mechanical seal device. Background technique [0002] Figure 7 is a cross-sectional view of a conventional mechanical seal device, Figure 8 yes Figure 7 Enlarged view of Section VIII. [0003] as a closed CO 2 Mechanical seals for high-pressure refrigerants such as Figure 7 The shown mechanical seal device 100 (for example, refer to Patent Document 1). The mechanical seal device 100 includes: an adapter ring 110 airtightly fixed on the casing 300 , a seal ring 120 that can rotate together with the rotating shaft 200 and slide closely with the adapter ring 110 , and a seal ring 120 clamped between the seal ring 120 and the rotating shaft 200 O-ring 130 in between. [0004] In this mechanical seal device 100, even wh...

AI Technical Summary

Problems solved by technology

[0005] However, since the refrigerant CO 2 is high pressure, therefore, as Figure 8 As shown, the O-ring 130 pressed toward the atmospheric environment Q side sometimes sinks into the gap g formed between the seal ring 120 and the rotating shaft 200

If the rotating shaft 200 moves in the thrust direction with the O-ring 130 caught in the gap g, the seal ring 120 will also move along with it, and as a result, the gap between the adapter ring 110 and the seal ring 120 will expand, sometimes Cannot ensure good sealing performance

[0006] In addition, the rubber constituting the O-ring has the property of being easily damaged by CO 2 Due to the nature of refrigerant penetration, sometimes the refrigerant will pass through the O-ring 130 and flow out to the atmospheric environment Q side, thus failing to ensure good sealing performance

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