JPH0740090Y2 - Oil removal device for piston rod surface - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for removing hydraulic oil attached as an oil film on the surface of a piston rod of a hydraulic cylinder.

[0002]

2. Description of the Related Art In a hydraulic cylinder provided in a hydraulic molding machine, even if a seal is provided on a lid member of a hydraulic cylinder into which a piston rod is inserted, the working oil in the hydraulic cylinder is in the form of an oil film and is on the surface of the piston rod. Adhere to.

Although the amount of oil adhered to the surface of the piston rod is slight, if the piston rod is stopped for a long time while it is still moving forward, the oil will naturally gather under the surface of the piston rod and collect. It becomes a drop and comes to drop on the upper surface of the machine base.

Therefore, conventionally, an oil absorbing member by a felt is provided together with a dust seal between the lid member of the hydraulic cylinder in which the piston rod is inserted and the lower side surface of the piston rod, so that the surface of the piston rod is attached. The oil is wiped off using the forward / backward movement of the piston rod.

The oil absorbing member is fitted in the drain groove on the lid member front side of the dust seal, and the oil absorbed by the felt is collected as a drain from the discharge passage formed in the drain groove.

[0006]

The problem with this conventional device is that if the piston rod is repeatedly moved forward and backward over a long period of time, the oil absorption by the oil absorbing member will decrease, and the flow will deteriorate and the oil will leak from the drain groove. That's what it means.

This is due to the limit of the absorption of the oil adhered by the felt, and in the felt which has reached the saturated state, the absorption capacity is lowered due to the swelling, and the flow resistance is increased to make the natural flow difficult.

[0008] This decrease in the absorption capacity cannot be improved unless the felt is returned to the unsaturated state by some means, so that the conventional technique is to replace the felt.

This invention was conceived in order to solve the above-mentioned conventional problems, and its purpose is to remove adhering oil on the surface of the piston rod not by absorption but by induction flow, and use for a long period of time. Even if the adhering oil does not leak from the drain groove, a new adhering oil removing device is provided.

[0010]

According to the features of the present invention, the oil guide member formed of a non-oil absorbing mesh structure is provided on the lower surface of the piston rod fitted into the lid member of the hydraulic cylinder. It is provided by being fitted in the drain groove provided in the.

[0011]

In the above device, when the piston rod moves, the oil adhering to the surface of the piston rod, which is in contact with the oil guiding member, travels through the linear portion forming the mesh structure to the oil guiding member side, It flows down naturally into the drain groove and is removed from the surface of the piston rod.

Further, since the oil guiding member has no oil absorption, the linear portion does not absorb oil and become saturated.

[0013]

1 and 2 show an embodiment in which an oil guide member is fitted to the inner peripheral side of a lid member, in which 1 is a hydraulic cylinder, 2 is a piston rod, and 3 is a hydraulic cylinder 1. It is a lid member that closes the open end.

A lid member 3 having the piston rod 2 inserted therethrough
A seal ring 4 and a dust seal 5 are provided on the inner peripheral side of the above, and a drain groove 6 is recessed inside the lid member facing the lower side of the piston rod outside the dust seal 5.

At the bottom of the drain groove 6, an oil discharge passage 7 is provided.
And the oil guide member 8 is located in the groove.

The oil guiding member 8 has a cell size of 6 to 2
It has a mesh structure of 0 cells / inch, and each cell is made of an elastic porous body made of a polymer such as urethane, which is open. Further, since it is composed of a large number of open cells 8a and a linear portion 8b in a bridged state that forms each open cell 8a in a mesh shape,
Water repellent and poorly absorbed.

The oil guiding member 8 is provided between the lower surface of the piston rod 2 and a deep groove in the drain groove so that the inner end surface of the oil guiding member 8 always maintains a proper contact and is provided between the oil guiding member 8 and the lid member 3. Has been.

The oil guiding member 8 may be installed outside the lid member 3. In this case, as shown in FIG. 3, a drain groove 6 having a discharge passage 7 is provided on the lower surface of the piston rod 2. Along the outer surface of the lid member 3, the oil guiding member 8 is housed in the drain groove.

In the above structure, even if the oil adhered to the upper surface and the side surface of the piston rod 2 flows to the lower surface while the piston rod 2 is stopped in the forward state, the inner surface of the oil guide member 8 is Since it is always in contact with the surface of the piston rod, the adhered oil flows through the linear portion 8b to the oil guiding portion when it comes into contact with the oil guiding member 8 due to the retreat of the piston rod 2, and further the drain groove. It will run down to 6.

Further, since the oil guide member 8 having a mesh structure does not have a function of absorbing or adsorbing the adhered oil, it does not become saturated like a felt even when it is used for a long period of time, and the adhered oil does not adhere to the member. The oil is guided to the linear portion 4b and is collected from the drain groove 6 as a discharge passage 7 and a flow drain.

Therefore, most of the oil adhered to the lower surface of the piston rod is removed by the oil guiding member 8 each time the piston rod 2 moves, so that the upper surface and the side surface adhere to each other while the piston rod 2 moves backward. Even if the oil gathers on the lower surface, it is difficult to form drops, and it is extremely rare to drop on the machine base.

Although the oil guiding member 8 is provided only on the lower side of the piston rod 2 in the above embodiment, it may be provided around the piston rod in some cases. At this time, the oil guiding member 8 is provided together with the deep groove. It may be formed in a ring shape.

Further, even if the oil guiding member 8 is not made of a polymer such as urethane but has a mesh structure of metal wool, the same effect can be obtained. Therefore, in the present invention, the oil guiding member is made of a polymer. It is not limited to one.

[0024]

As described above, according to the present invention, the lower surface of the piston rod 2 fitted into the lid member 3 of the hydraulic cylinder 1 is
Since the oil guide member 8 made of a non-oil absorbing mesh structure is fitted into the drain groove 6 provided on the lid member side, the drawback of removing the adhered oil by absorption is eliminated, and the lower surface Not all of the attached oil is removed,
The oil that adheres to the portion that does not come into contact with the linear portion remains as an oil film, so it does not affect the forward / backward movement of the piston rod.

Further, since the linear portions forming the net-like structure are separated by the gaps such as cells, it is difficult for the adhered oil to be absorbed and adsorbed by the capillary phenomenon, and the adhered oil flows down without staying in the gap. Therefore, collection as a drain becomes easy.

Furthermore, when a polymer porous material is used as the oil guiding member, since the oil guiding member has elasticity, the condition of contact with the piston rod surface is good and it is also strong against friction, so that it is used for a long period of time. It also has the advantage that it does not require frequent replacement.

[Brief description of drawings]

FIG. 1 is a half sectional view of a hydraulic device equipped with a device for removing adhering oil on the surface of a piston rod according to the present invention.

FIG. 2 is a sectional view of an adhered oil removing portion.

FIG. 3 is a cross-sectional view of an adhered oil removing portion of another embodiment. 1 Hydraulic Cylinder 2 Piston Rod 3 Lid Member 4 Seal Ring 5 Dust Seal 6 Drain Groove 7 Discharge Path 8 Oil Induction Member 8a Open Cell 8b Linear Part

 ─────────────────────────────────────────────────── ───Continued from the front page (56) Bibliographic data Sho 56-158561 (JP, U) Real development Sho 56-111302 (JP, U) Real development Sho 52-139995 (JP, U)

Claims (1)

[Scope of utility model registration request] 1. An oil guiding member made of a non-oil absorbing mesh structure is provided on a lower surface of a piston rod fitted into a lid member of a hydraulic cylinder by being fitted in a drain groove on the lid member side. A device for removing oil on the surface of the piston rod.