JPS61157877A - Packing for sliding - Google Patents

Abstract

PURPOSE:To enhance the grease retaining function by providing ring-shaped division walls between a main grease groove and auxiliary grease grooves, and making the diameter at the edge part of the division wall nearly equal to the outside diameter of sliding part. CONSTITUTION:Ring-shaped division walls 13 and 14 are formed between a main grease groove 10 and each of auxiliary grease grooves 11 and 12, and the inside diameter of these walls is nearly equal to the outside diameter of a rod 2. Grease is supplied to a front main lip 8 from the front auxiliary groove 11 adjacent to it, and is supplied to a rear auxiliary lip 9 from the rear auxilia ry grease groove 12 adjacent to it. Further, to both auxiliary grooves 11 and 12, grease is gradually supplied from a main grease groove 10 which has a greater cross-sectional area than the auxiliary grooves.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a sliding packing used in a reciprocating actuator such as a pneumatic cylinder device or a hydraulic cylinder device, and particularly to a long-stroke oil-free sliding packing.

(Prior art and its problems) (Prior art and its problems) A conventional sliding packing is provided with lips 8.9 at both ends in the axial direction, for example, as shown in FIG. One annular grease groove 21 is provided. However, if there is only one grease groove 21, when the grease in the groove 21 decreases after long-term use, the grease in the grease groove 21 will be biased to one side in the axial direction, and both lips 8.9 will not be evenly lubricated. It disappears. Furthermore, when used for a long time in a long stroke device, the grease flows out quickly and there remains a problem in terms of grease retention.

(Object of the Invention) The object of the present invention is to enable the lips at both ends of the packing to always slide evenly a1, and to improve the grease retention function.

(Means for Achieving the Object) In order to achieve the above object, the present invention forms an annular lip that presses against the sliding member at both ends of the annular packing in the axial direction on the sliding surface side, and forms an annular lip between the inner annular lip. An annular main grease groove is formed in the center of the main grease groove, and annular sub-grease grooves having a smaller cross-sectional area than the main grease groove are formed on both sides of the main grease groove in the axial direction.
An annular partition wall is provided between the main grease groove and the sub-grease groove, and the diameter of the tip of the partition wall is set to be approximately equal to the outer diameter of the sliding member.

(Example) Fig. 1 is a partial vertical cross-sectional view of a pneumatic cylinder device to which the present invention is applied. In Fig. 1, 1 is a cylinder housing, 2 is a sliding rod, and the rod 2 is a cylinder housing. 1 through a sliding packing 3 so as to be slidable in the longitudinal direction of the rond. The housing 1 is provided with a working air chamber 1a. The sliding stroke of the rod 2 is, for example, a long stroke of 2500+a, and the working air pressure is, for example, 5 Kyf/l:i. An annular groove 4 for fitting a seal is formed on the inner peripheral surface of the housing 1.
The annular packing 3 is fitted into the annular groove 4.

The packing 3 is made of, for example, nitrile rubber, and an annular lip 5 on the outer diameter side is formed in a forward-protruding shape on the front end (pressure side) of the outer peripheral surface of the packing 3, and an annular protrusion 6 facing outward is formed on the front end (pressure side) of the outer peripheral surface of the packing 3. It is formed. An annular main lip 8 on the inner diameter side is formed at the front end in the axial direction of the inner peripheral surface of the packing 3, and the rear end (
An annular sub-lip 9 is formed on the atmospheric pressure side). An annular main grease groove 10 is formed in the center between both lips 8.9 on the inner diameter side, and auxiliary grease grooves 11 are formed on both sides of the main grease groove 10 in the axial direction, respectively close to each lip 8.9.
．． 12 are formed. An annular partition wall 13.14 is provided between the main grease groove 10 and each sub-grease groove 11.12.
is formed. Partition wall when installing packing 13.1
The inner diameter dimension D1 of the rod 2 is approximately the same as the outer diameter D2 of the rod 2, and it is preferable that the inner peripheral edge of the partition wall 13.14 abuts against the outer peripheral surface of the rod 2 with a substantially pressure O or is close to it. . The inner diameter dimension D3 of the front and rear lips 8.9 on the inner diameter side is smaller than the outer diameter D2 of the rod 2, and when the seal is attached, the lip 8.9 is compressed and seals against the surface of the rod 2 with a predetermined sealing pressure. Pressure contact.

Grease is injected into the main grease groove 10 and the sub-grease grooves 11.12. Note that FIG. 1 shows the shape of the packing 3 in its natural state (uncompressed state).

(Function) When the rod 2 slides in the axial direction, the main lip 8 at the front is supplied with grease from the grease groove 11 at the front close to it, and the sub lip 9 at the rear is supplied with grease from the grease groove 11 at the front close to it. Grease is supplied from the rear grease groove 12.

Further, grease is gradually supplied to both side grease grooves 11 and 12 from the main grease groove 10 having a larger cross-sectional area. Therefore, the grease is not biased toward either the front or the rear, and both lips 8.9 are evenly and well lubricated.

From the main grease groove 10 in the center to the sub-grease grooves 11, respectively.
．． Since the grease is supplied to the front and rear lips 8.9 through 12, the amount of grease flowing out to the outside can be suppressed to a small amount, and the grease retention performance is good.

(Another Embodiment) (1) The embodiment shown in FIG. 2 is an example in which the rear sub-lip 9 is formed in a diagonal projecting shape to prevent dust from entering.

(2) Although the embodiments shown in FIGS. 1 and 2 are applied to a gasket that fits on the inner circumferential surface of a housing, the present invention can also be applied to a gasket that is attached to a fitting groove on the outer circumferential surface of a piston, etc. Applicable. In that case, the main grease groove, the sub-grease groove, the main lip, and the sub-lip are formed on the outer peripheral surface of the packing.

(3) Sky as shown. In addition to pneumatic cylinder devices, the present invention can be applied to various reciprocating actuators such as hydraulic cylinder devices.

(Effects of the Invention) (1) A1 grease grooves 11.12 are formed close to the annular lips 8.9 at both ends in the axial direction, and the main grease groove 10 with a large cross-sectional area is formed between the grease grooves 11.12 on both sides.
A main grease groove 10 and a sub-grease groove 11.12 are formed.
Since partition walls 13 and 14 are provided between the lips 8 and 9, even if the grease decreases after long-term use, the grease will not be distributed to either the front or the rear, and both lips 8 and 9 will always be spread evenly and well. Can be lubricated.

Therefore, good sealing performance and good lubrication performance can be ensured at the same time.

(2) Annular sub-grease grooves 11 and 12 having a smaller cross-sectional area than the main grease groove are formed on both sides of the main grease groove 10 in the axial direction, and main grease W410 and sub-grease tiii, 12 are formed.
The diameter of the tip of the partition wall 13.14 between the main grease groove 10 and each sub-grease groove 11.12 is set so that it contacts or approaches the sliding member with almost zero pressure when the seal is installed. Grease is supplied to each lip 8.9 in a two-stage manner through the , which prevents unnecessary flow of grease to the outside and allows good grease preservation.

Therefore, the lifespan of the packing is extended. By the way, as an experimental example of the present invention, the air pressure was 5.9f/ci and the stroke length was 2500J11. It has been confirmed that when the speed is set to 1.57 FL/S, the life span is longer than 5000/c111 runs.

[Brief explanation of the drawing]

FIG. 1 is a partial vertical cross-sectional view of a gasket to which the present invention is applied, FIG. 2 is a partial vertical cross-sectional view of a modified example of the gasket, and FIG. 3 is a partial vertical cross-sectional view of a conventional example. 2... O Rad (ll!! An example of a moving member), 3... Packing, 8.9... Lip, 10... Main grease groove, 11.12... Sub-grease groove, 13 .14...Partition wall patent applicant Dainichi Nippon Electric Cable Co., Ltd....Y-1st grade

Claims (1)

[Claims] An annular lip that presses against the sliding member is formed at both axial ends of the sliding surface side of the annular packing, an annular main grease groove is formed in the center between both annular ribs, and an annular main grease groove is formed at both axial ends of the main grease groove. An annular sub-grease groove with a smaller cross-sectional area than the main grease groove is formed in the groove, an annular partition wall is provided between the main grease groove and the sub-grease groove, and the diameter of the tip of the partition wall is set to the diameter of the sliding member. A sliding packing characterized by being set to be approximately equal to the outer diameter.