JPH10115373A - Manufacture of sealing device and sealing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the generation of molding burr on a surface of a reinforcement ring, by comprising a circular inclination part inclined and connected to at least one edge of a contact face of the reinforcement ring installed in a sealing device, loading the reinforcement ring on a die comprising a circular projection to be kept into contact with the circular inclination part, and performing the molding by the closing. SOLUTION: In the molding of a sealing device for sealing a gap of a shaft to be inserted into a housing member, a connecting part 11d of a reinforcement ring 11 is supported on a ring-shaped projection 51b of a lower die 51, and then an inner peripheral edge of a contact face 11c of the reinforcement ring 11 is supported on a positioning part 51c. Then a rubber elastic member R is loaded on a specific position of a circular cavity C formed by the lower die 51 and a medium die 53, and then an upper die 52 is closed. A radial part 11b is pressed to the circular projection 51b and the positioning part 51c by the pressure of the softened rubber elastic member R. When the engagement part is formed thereby, the approaching of the boundary of the engagement part to a position ahead of the contact area of the connecting part 11d and the circular projection 51b, is prevented, and the generation of the molding burr on the contact face 11c can be inhibited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sealing device manufactured by molding a rubber-like elastic material, and relates to a manufacturing method and a product thereof in which molding burrs do not occur on the surface of a reinforcing ring.

[0002]

2. Description of the Related Art Conventionally, as a sealing device for sealing between a housing member and a shaft inserted through the housing member,
There is a sealing device 101 as shown in FIG. In the sealing device 101, the housing 102 and the shaft 103 move relatively in the axial direction by the action of hydraulic oil such as high-pressure oil. Prevents oil leakage.

[0003] A sealing device 101 includes a reinforcing ring 1 having an L-shaped cross section.
A lip portion 110 is provided on the inner peripheral side of the housing 11, and a fitting portion 1 is provided on the outer peripheral side thereof for maintaining the sealing performance when fitting the housing member 102.
12 are provided. These lip portion 110 and fitting portion 11
Numeral 2 is formed by vulcanization molding, and a rubber-like elastic material, which is a material inside the mold at the time of molding, heats and flows, gets over the axial portion 111a of the reinforcing ring 111, and becomes integral. I have.

[0004] Reference numeral 120 denotes a spring for maintaining the tension of the lip tip 110a of the lip 110.
Reference numeral 130 denotes a support ring for preventing the lip 110 from turning or turning when sliding.

[0005] Such a sealing device 101 is fitted on the inner peripheral surface of the housing member 102, but the radial portion 111 b of the reinforcing ring 111 is abutted against the end surface 104 a of the member 104 so as not to move due to the pressure of the hydraulic oil. Is pressed against.

[0006]

In this type of sealing device 101, however, the rubber-like elastic material which has wrapped around the reinforcing ring 111 during molding flows to the radial portion 111b of the reinforcing ring 111, There is a problem that the radial portion 111b is covered as a thin film-shaped molding burr. This problem is a general problem that occurs at the time of rubber molding. Conventionally, there is no effective solution. It has been necessary to take measures such as stripping or manually removing thin molding burrs after molding.

[0007] However, as shown in FIG.
If the thin burr 113 is incorporated into a product with the thin burr 113 remaining, the burr 113 is compressed by being sandwiched between the reinforcing ring 111 and the end surface 104 a of the abutting member 104.

In a use environment where a constant compression state is maintained, the molding burr 113 can be used so as to function as a joining member or a seal, and there is no problem in some cases. In a moving or vibrating use environment, that is, when the pressure fluctuation of the hydraulic oil is large, a fluctuating load is applied to the sandwiched molding burr 113, and the molding burr 113 is damaged, such as deterioration or peeling. . When the broken molding burr 113 becomes a foreign matter from between the reinforcing ring 111 and the end surface 104a of the abutting member 104 and enters the sealing area, it mixes with the hydraulic oil to block the hydraulic path, and the lip 110 of the sealing device 101 It is conceivable that a problem such as a decrease in sealing performance due to biting occurs.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and an object of the present invention is to eliminate molding burrs generated on the surface of a reinforcing ring at the time of molding, and to remove burrs after molding. It is an object of the present invention to provide a highly reliable sealing device which can be made unnecessary and prevent generation of foreign matters due to deterioration or peeling of molding burrs during use, and to disclose a method of manufacturing the sealing device.

[0010]

In order to achieve the above object, in a method of manufacturing a sealing device according to the present invention, a reinforcing ring having a contact surface when the sealing device is mounted, and a reinforcing ring formed integrally with the reinforcing ring. A sealing portion made of a rubber-like elastic member,
In the method for manufacturing a sealing device provided with, the reinforcing ring,
The reinforcing ring is mounted on a mold having an annular sloping portion that is inclinedly connected to at least one end of the abutting surface and provided with an annular ridge that abuts on the annular sloping portion of the reinforcing ring. And forming the reinforcing ring while pressing the reinforcing ring against a forming die.

According to this manufacturing method, since the annular ridge portion of the molding die comes into contact with and is pressed against the annular inclined portion of the reinforcing ring during molding, a sealing property is obtained by the contact pressure. And
The rubber-like elastic member flowing at the time of molding is molded without protruding to the contact surface side with the portion where the annular ridge of the annular inclined portion abuts as a boundary.

Further, the molding die may be provided with a positioning portion which comes into contact with a contact surface of the reinforcing ring. Accordingly, it is possible to prevent inclination and displacement when the reinforcing ring is set in the molding die. As the positioning portion, it is preferable to apply a seating surface that comes into contact with the contact surface at the opposite end to which the annular inclined portion of the reinforcing ring connects, or a positioning shaft that is inserted into the inner diameter end of the reinforcing ring.

Further, the annular ridge of the molding die may include a plurality of ridges facing each other along the annular inclined portion of the reinforcing ring. With the annular ridge having such a shape, even if there is some variation in the size of the annular inclined portion of the reinforcing ring, any one of the ridges comes into contact with the annular inclined portion of the reinforcing ring. It is possible to ensure the sealing performance by pressure. Further, the flow path of the rubber-like elastic member is gradually narrowed by the annular ridge portion which is close to the annular inclined portion but does not abut, and the pressure of the rubber-like elastic member at the boundary portion is reduced. It is prevented from protruding further to the contact surface side.

It is also possible that the reinforcing ring is pressed against the mold by the pressure generated by the rubber-like elastic member during molding after the mold is closed.

On the other hand, in the sealing device, a reinforcing ring having a contact surface when the sealing device is attached, a sealing portion made of a rubber-like elastic member integrally formed with the reinforcing ring,
In the sealing device, the reinforcing ring includes an annular inclined portion that is inclined and connected to at least one end of the contact surface, and the seal portion includes a boundary portion of the rubber-like elastic member on the annular inclined portion. The reinforcing ring is formed on the opposite side of the contact surface of the reinforcing ring from the boundary.

Therefore, the rubber-like elastic member does not exist on the contact surface of the sealing device, and stable mounting can be performed.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on the illustrated embodiment.

(Embodiment 1) FIG. 1 is a sectional view showing a state in which a sealing device 1 according to a first embodiment of the present invention is applied to an inner peripheral portion of a housing member 2. This sealing device 1 seals between a housing member 2 and a shaft 3 inserted through the housing member 2.

The housing member 2 and the shaft 3 are relatively moved in the axial direction by the action of hydraulic oil such as high-pressure oil.
The lip 10 of the sealing device 1 hits the sliding surface of the shaft 3 to prevent leakage of hydraulic oil.

The sealing device 1 has a lip portion 10 as a sealing portion on the inner peripheral side of a reinforcing ring 11 having an L-shaped cross section, and a sealing portion on the outer peripheral side for maintaining the sealing performance when fitted to the housing member 2. Is provided. The lip portion 10 and the fitting portion 12 are formed by, for example, vulcanization molding, and a rubber-like elastic material serving as a material is heated and flows inside the mold at the time of molding, and the axial portion 11a of the reinforcing ring 11 is formed. It has become an integral part of getting over.

Reference numeral 20 denotes a lip tip portion 10 of the lip portion 10.
This is a spring for maintaining the tension of a. Also,
Reference numeral 30 denotes a support ring for preventing the lip 10 from turning or turning when sliding.

The sealing device 1 is fitted to the inner peripheral surface of the housing member 2, but the radial portion 11b of the reinforcing ring 11 is abutted against the end surface of the member 4 so as not to move in the axial direction due to the pressure of the hydraulic oil. 4a.

The radial portion 11b of the reinforcing ring 11 has a surface opposite to the lip portion 10 as an abutting surface 11c which abuts against the end surface 4a of the abutting member 4. Also, the axial portion 11a
A connecting portion 11d between the radial direction portion 11b and the radial direction portion 11b functions as an annular inclined portion inclined from the contact surface 11c, and has a round shape in the present embodiment.

The boundary 12a of the fitting portion 12 is located at the connecting portion 11d,
a is not in contact.

Therefore, the sealing device 1 can be positioned in the axial direction by the contact surface 11c where the rubber-like elastic member does not exist, and the sealing device 1 is moved or vibrated in the axial direction. Even in the used environment, there is no thin molding burr according to the prior art on the contact surface 11c, and it is possible to suppress the problem due to the generation of foreign matter and to reduce the sealing performance, and improve the reliability of the sealing device 1.

(Embodiment 2) FIG. 2 is a view for explaining a method of manufacturing a sealing device 1 to which the present invention is applied as a second embodiment. It is in a state molded inside.

The features of the manufacturing method according to the present invention mainly reside in an annular inclined portion provided on the reinforcing ring 11 of the sealing device 1 and a mold used for molding the sealing device 1.

The reinforcing ring 11 is the same as that described in the first embodiment, and is an annular member having a substantially L-shaped cross section.

The basic configuration of the molding die 50 is the same as that of the conventional one, and comprises a lower die 51, an upper die 52 and a middle die 53.

The lower mold 51 has an annular axial wall 51a forming the fitting portion 12 of the sealing device 1 and a reinforcing ring 11 on a base portion continuous from the rising portion of the axial wall 51a in the radial direction.
Annular ridge 51b supporting the connecting portion 11d of the
The positioning portion 51 that determines the axial position of the reinforcing ring 11 together with the annular ridge portion 51b by holding the first contact surface 11c.
c, and the inner diameter end 11e of the radial portion 11b of the reinforcing ring 11
Is provided with a cylindrical positioning stud 51d that fits into the positioning stud 51d.

A concave portion is formed between the annular ridge portion 51b and the positioning portion 51c.
It is preferable to limit the elastic deformation region in which the shape 1 returns to the original shape even if it is bent by the pressure at the time of molding.

The upper mold 52 is provided with a protruding portion 52a which forms a shape of the lip portion 10 on the side where the spring 20 is fitted when the mold is closed. The outer diameter side is the lower mold 51
Abuts on the upper end surface 51e of the axial wall 51a,
It is in contact with the outer peripheral upper end 53a of the middle die 53. In order to easily open the mold, the upper mold 52 is divided into a plurality of pieces in a radial manner as appropriate.

The middle mold 53 has a groove 1 into which the lip tip 10a of the sealing device 11 and the support ring 30 are fitted.
0e is formed. The middle mold 53 is removably positioned at the center of the lower mold 51 by means of a stainless steel fitting.

Therefore, when the mold is closed, the lip portion 10 and the fitting portion 12 which are the seal portion of the sealing device 1 are formed by the axial wall 51a of the lower mold 51, the lower surface of the upper mold 52, and the outer periphery of the middle mold 53. Thus, an annular cavity C is formed.

The molding process of the sealing device 1 is as follows.
First, the mold is opened and the cylindrical positioning stud 5 of the lower mold 51 is opened.
1d is fitted into the reinforcing ring 11 with the contact surface 11c facing downward. Then, the annular ridge portion 51 b is connected to the connecting portion 1 of the reinforcing ring 11.
1d, and the positioning portion 51c supports the inner peripheral end of the contact surface 11c of the reinforcing ring 11.

Next, the middle mold 53 is fitted into the lower mold 51, and the upper part formed by the lower mold 51 and the middle mold 53 is fluidized and expanded at the time of molding into the annular cavity C whose upper side is open, and the hermetic seal filled in the cavity C is formed. A rubber-like elastic member R serving as a material of a seal portion of the device 1 is placed at a predetermined position (the position indicated by a two-dot chain line in the figure).

Then, the upper mold 52 is closed in the direction of the arrow A1, and molding involving pressurization and heating is performed. At the time of molding, the radial portion 11b of the reinforcing ring 11 is pressed against the annular ridge portion 51b and the positioning portion 51c of the lower mold 51 by the pressure (arrow A2) of the rubber-like elastic member R softened by heat. At this time, the molding pressure is 200 to 400 (kgf / cm
² ) Since about pressure is applied, the connecting portion 11 of the reinforcing ring 11
d is in contact with the annular ridge portion 51b so as to bite and is sealed with a high contact pressure. By pressing the radial portion 11b with the molding pressure, for example, the upper die 52 is provided with a pressing portion for pressing the reinforcing ring 11, and the influence of the dimensional variation of the reinforcing ring 11 (for example, There is no height dimension of the axial portion 11a), and it can be stably pressed.

Therefore, when the rubber-like elastic member R flows outward to form the fitting portion 12, the boundary portion 12a is
It is possible to suppress the generation of molding burrs on the contact surface 11c without entering beyond the portion where 1d and the annular ridge 51b contact.

When the flow and crosslinking and curing of the rubber-like elastic member R are completed, the upper mold 52 is opened while being divided, the middle mold 53 is pulled out, and the molded sealing device 11 is taken out.

In the case where the axial portion 11a of the reinforcing ring 11 is formed as an annular contact surface, the present invention employs a method in which the rubber-like elastic member R is formed so as to wrap around from the radial portion 11b. It is possible to apply

(Embodiment 3) FIG. 3 is a view for explaining a method of manufacturing a sealing device 1 to which the present invention is applied as a third embodiment. As a feature of this embodiment, the annular ridge 51b provided on the lower die 51 of the molding die 50 in the second embodiment is formed as a plurality of protrusions 60 (three in this figure).

According to the ridge 60, even if there is a slight variation in the size of the connection portion 11d of the reinforcing ring 11, any one of the ridges comes into contact and the sealing performance by the contact pressure can be ensured. Becomes Further, a flow path of the rubber-like elastic member R is gradually narrowed by a ridge (a left-side ridge in this figure) which is close to but not in contact with the connection portion 11d, and the pressure of the rubber-like elastic member at the boundary portion 12a is gradually reduced. Is reduced, the boundary 1
2a is prevented from protruding toward the contact surface 11c from the ridge 60 contacting the connection portion 11d.

[0043]

According to the present invention described in the above embodiment, it is possible to eliminate molding burrs generated on the surface of the reinforcing ring at the time of molding, and the deburring operation becomes unnecessary. In addition, when the completed sealing device is used, it is possible to prevent the generation of foreign matter due to the deterioration or peeling of the molding burrs, so that the sealing performance is maintained and the reliability is improved.

The positioning portion abutting on the radial portion of the reinforcing ring of the molding die can prevent inclination and displacement when the reinforcing ring is set on the molding die.

The annular ridge provided with a plurality of ridges allows variation in the size of the reinforcing ring, reduces the pressure of the rubber-like elastic member at the boundary, and more reliably prevents the formation of molding burrs. Can be suppressed.

Since the reinforcing ring is pressed against the molding die by the pressure generated by the rubber-like elastic member at the time of molding, the annular inclined portion and the annular ridge portion are stably abutted, and the generation of molding burrs is suppressed.

[Brief description of the drawings]

FIG. 1 is an explanatory cross-sectional view of a sealing device according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a method for manufacturing a sealing device according to a second embodiment of the present invention.

FIG. 3 is a diagram illustrating a method for manufacturing a sealing device according to a third embodiment of the present invention.

FIG. 4 is an explanatory sectional view of a conventional sealing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Sealing device 2 Housing member 3 Shaft 4 Butt member 4a End surface 10 Lip part (seal part) 10a Lip tip part 11 Reinforcement ring 11a Axial part 11b Radial part 11c Contact surface 11d Connection part (annular inclined part) 11e Inner diameter End part 12 Fitting part 12a Boundary part 20 Spring 30 Support ring 50 Mold 51 Lower die 51a Axial wall 51b Annular ridge 51c Positioning part 51d Positioning stud 52 Upper die 53 Middle die 53a Upper end of outer periphery C cavity R Rubber-like elasticity Element

Claims (5)

[Claims] 1. A method of manufacturing a sealing device, comprising: a reinforcing ring having a contact surface when attaching a sealing device; and a sealing portion made of a rubber-like elastic member formed integrally with the reinforcing ring. The reinforcing ring includes an annular inclined portion inclined and connected to at least one end of the contact surface of the reinforcing ring, and a reinforcing die provided with an annular ridge that contacts the annular inclined portion. A method for manufacturing a sealing device, comprising: mounting a sealing ring on a mold; and pressing the reinforcing ring against a mold. 2. The method for manufacturing a sealing device according to claim 1, wherein the molding die is provided with a positioning portion that comes into contact with a contact surface of the reinforcing ring. 3. The sealing device according to claim 1, wherein the annular ridge portion of the molding die includes a plurality of ridges facing each other along the annular inclined portion of the reinforcing ring. Manufacturing method. 4. The sealing device according to claim 1, wherein the reinforcing ring is molded while being pressed against a molding die by a pressure generated by a rubber-like elastic member at the time of molding after closing the mold. Manufacturing method. 5. A sealing device comprising: a reinforcing ring having a contact surface when mounting a sealing device; and a sealing portion made of a rubber-like elastic member formed integrally with the reinforcing ring. The ring includes an annular inclined portion that is inclined and connected to at least one end of the contact surface, and the seal portion locates a boundary of the rubber-like elastic member on the annular inclined portion and moves the seal from the boundary. A sealing device formed on a side opposite to a contact surface of a reinforcing ring.