JPH0339455B2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a method for manufacturing a rubber sleeve having an inner surface rubber layer, a reinforcing layer, and an outer surface rubber layer and having an overall cylindrical shape. .

(Prior art) After completion of vulcanization molding, each end portion is airtightly connected to an inner cylinder and an outer cylinder, which are applied as a diaphragm of a door phragm type air spring and are relatively movable in the axial direction. An air spring can be constructed by In a conventionally known cylindrical rubber sleeve, each of the band-shaped reinforcing members, which have two inner and outer layers between an inner rubber layer and an outer rubber layer, and each of which has a reinforcing cord, has an intersection angle of 30° to 60° with the sleeve axis. In the reinforcing layer arranged in a spiral shape so as to be mutually symmetrical within the range of ゜,
In order to prevent punctures under the usage conditions after vulcanization molding, and to prevent a decrease in manufacturing accuracy due to misalignment of the reinforcing members, each reinforcing member is Since each side end portion of the reinforcing member overlaps with a width of 1 to 10 mm, the rigidity of each overlapping portion of the reinforcing member is higher than that of other portions when used as a diaphragm after vulcanization molding of the rubber sleeve. This change in rigidity in the longitudinal direction of the diaphragm causes local stress concentration on it, and this stress concentration often causes damage to the diaphragm.In addition, the overlapped portion of the reinforcing member causes damage to the rubber on the inner and outer surfaces. There were problems such as the layer being exposed and air leaking from there.

Therefore, without overlapping the widthwise end portions of the reinforcing member having the reinforcing cord, in other words, the reinforcing member of a predetermined width can be shaped into a cylindrical shape, with both end surfaces of the reinforcing member in contact with each other or separated from each other by some distance. A rubber sleeve has been proposed that is spirally wrapped around the outer circumferential side of an inner rubber layer, and this rubber sleeve can sufficiently solve the problem caused by the reinforcement members overlapping in the width direction. It is said that

(Problems to be Solved by the Invention) However, in reality, the technology for manufacturing the proposed sleeve accurately as expected has not yet been established, and in particular, the angle between the reinforcing member and the sleeve axis has not yet been established. Since it is extremely difficult to always reliably maintain a predetermined value, the intention is to have both side end surfaces of the reinforcing member contact each other, but as a result, both side end portions overlap, and the both end surfaces are Although it is intended to be separated by a predetermined distance, a gap of more than a predetermined amount often occurs between the side end surfaces, and the former phenomenon causes the same problem as with conventional rubber sleeves, and the latter phenomenon causes problems. In this case, the rubber material of at least one of the inner rubber layer and the outer rubber layer flows between both end surfaces of the spirally wound reinforcing member during vulcanization molding, and either the inner surface of the inner rubber layer or the outer surface of the outer rubber layer flows. There was a problem that cracks occurred on both sides of the comb.

This invention advantageously solves the problem of the prior art, and when winding a reinforcing layer forming material formed by rubber-coating a reinforcing cord around the outer periphery of a cylindrical inner rubber layer in a spiral manner, To provide a method for manufacturing a rubber sleeve that is free from problems caused by overlapping reinforcing layer forming materials and surface cracking of inner and outer rubber layers even if a slight error occurs in the angle. It is.

(Means for Solving the Problems) The method of manufacturing a rubber sleeve of the present invention is particularly characterized in that the rubber sleeve is made by rubber-coating a plurality of reinforcing cords, which are an example of a blind weave cord, and has a predetermined width and a width. The reinforcing layer is formed by spirally wrapping a reinforcing layer forming material having an ear rubber of a constant width on at least one side of the cylindrical surface around the outer periphery of an unvulcanized or vulcanized inner cylindrical rubber layer. The respective side edges of the reinforcing layer forming material are aligned so that the reinforcing cord located closest to the side edge of the reinforcing layer forming material overlaps the base of the ear rubber and both end surfaces of the reinforcing layer forming material are mutually aligned. The unvulcanized reinforcing layer is bonded between the contact point and the unvulcanized reinforcing layer.

(Function) In this manufacturing method, since a rubber band with a certain width is present at at least one side end of the reinforcing layer forming material, reinforcement is provided at the center of the rubber band with an appropriately selected width. In order to position the other side edge of the layer-forming material, when wrapping the reinforcing layer-forming material in a helical manner while overlapping each other, the winding angle may be slightly different from the intended angle. Even in this case, overlapping of the reinforcing cords in the reinforcing layer forming material and separation of both side edges of the reinforcing layer forming material from each other can be effectively prevented. In other words, by selecting the ear rubber width while anticipating the deviation in the wrapping angle, each side edge of the reinforcing layer forming material is set to the reinforcing cord located closest to the side edge of the reinforcing layer forming material. but,
They are always joined between the position that overlaps the base of the ear rubber and the position where both end surfaces of the reinforcing layer forming material touch each other, and therefore,
Even if the maximum deviation occurs, the reinforcing cord located closest to the side edge of the reinforcing layer forming material is the reinforcing cord located closest to the other side edge of the reinforcing layer forming material. The above-mentioned winding is performed in a state in which the reinforcing layer forming material is disposed adjacent to the reinforcing layer forming material, or in a state in which both end surfaces of the reinforcing layer forming material are in contact with each other.

(Example) This invention will be explained below based on the drawings.

FIG. 1 is a schematic plan view illustrating an embodiment of the present invention.

In addition to the method of forming the rubber sleeve using the equipment shown here, the inner rubber layer, reinforcing layer, and outer rubber layer can be sequentially laminated by hand without using any mandrels or forming rolls. A method of forming, using a forming roll, on which only rotational movement is performed at a predetermined position,
There have been widely known methods for workers to apply the inner rubber layer material, reinforcing layer material, and outer rubber layer material in sequence, and to use the apparatus disclosed in Publication of Utility Model Publication No. 56-25867. Although it is
For convenience of explanation, an example in which the illustrated apparatus is used will be described below.

In the figure, 1 is a molding table, and 2 is a mandrel placed on the molding table 1 in contact with it. This mandrel 2 is rotatably supported at both ends by bearings 3, 3, and these bearings are respectively oriented in the length direction of the forming table 1, in other words, in a direction perpendicular to the mandrel axis. It is slidably engaged with guide rails 4, 4 laid down on the molding table. Here, the mandrel 2 is guided by guide rails 4, 4 in its forward and backward movement with respect to the forming table 1, which involves rotational movement around its axis.

Here, when forming the unvulcanized inner rubber layer, reinforcing layer, and outer rubber layer on the mandrel 2, first, the inner rubber layer forming material 5, the reinforcing layer forming materials 6 and 6 are placed on the molding table 1. The outer rubber layer forming materials 7 are arranged one after another from the mandrel side at predetermined intervals.

The reinforcing layer forming material 6 here may be, for example, a blind weave cord coated with rubber. The molding table 1 is arranged with both side edges inclined with respect to the longitudinal direction of the molding table 1 so as to form a predetermined angle with respect to the axis of the molding table 1 . In this example, two reinforcing layer forming materials 6, 6 facing in opposite directions are arranged on the molding table 1, but the number of reinforcing layer forming materials 6, 6 can of course be changed as necessary. .

Furthermore, the reinforcing layer forming materials 6, 6 in this invention have one side or both sides in the width direction,
In the illustrated example, one side has an ear rubber 6a having a constant width according to requirements, and such a reinforcing layer forming material 6
When winding the reinforcing layer forming material 6 spirally around the outer circumferential side of the pre-formed inner rubber layer, the reinforcing layer forming material 6 is attached to the other side of the reinforcing layer forming material 6 at the widthwise center position of the ear rubber 6a in its width direction. It is placed on the forming table 1 at an angle of inclination that can bring about an overlapping condition of both side end portions, such that the side edges are exactly located.

Next, the mandrel 2 is rotated and moved forward with respect to the forming table 1, so that the forming materials 5, 6, and 7 of each layer are sequentially wound around the outer circumferential side of the mandrel 2 based on their inherent adhesive force. Then, an unvulcanized inner gum layer, two reinforcing layers, and an outer rubber layer are formed.

Here, the materials 5 and 7, which are arranged without being inclined with respect to the length direction of the forming table 1, are
To properly form an inner rubber layer and an outer rubber layer without being forced to change the arrangement posture due to the action of an external force on the rubber layer 7.

On the other hand, the reinforcing layer forming material 6, which is tilted and arranged on the molding table 1, is subjected to local compressive or tensile external force in the length direction of the molding table 1 due to the indirect contact of the mandrel 6 thereto. In many cases, the position of the reinforcing layer forming material 6 is changed slightly due to the existence of the ear rubber 6a whose width is selected in consideration of the change in position. Even if the reinforcing cords of the material 6 are changed, the reinforcing cords of the material 6 will not overlap with each other after the winding is completed, and conversely, the material 6 will not be separated from each other in its width direction.

In other words, when the reinforcing layer forming material 6 receives a local external force in the compression direction as shown by arrow A in the figure from the mandrel 2, its inclination angle α with respect to the forming table axis increases. , an arrangement that brings about an overlapping state in which the other side edge of the material 6 is exactly located at the center position in the width direction of the ear rubber 6a when the material 6 is placed in the above-mentioned position, that is, in the wrapped state of the material 6. Even if the posture is changed to the limit, each side end of the reinforcing layer forming material 6 after winding is completed.
As is clear from the reinforcing layer 16a of the inner layer shown in the cross-sectional view in FIG. 2, both end surfaces of the material 6 are joined with each other in contact with each other, and a gap is generated between the side end surfaces. Never. And vice versa,
When the reinforcing layer forming material 6 receives a local external force in the tensile direction and its inclination angle α becomes small to the limit, each side end of the material 6 after winding is the outer layer shown in FIG. As is clear from the reinforcing layer 16b, the reinforcing cord located closest to the side edge of the material 6 is joined to the base of the ear rubber 6a in an overlapping state, so that each side edge The reinforcing cords of the sections do not overlap each other.

Here, when the magnitude of the external force in the compression or tension direction is intermediate, the respective side ends of the material 6 are joined to each other at an intermediate position in each case described above. become.

The case where the reinforcing layer forming material 6 receives external forces in both compression and tension directions from the mandrel 2 has been described above, but when forming the reinforcing layers 16a and 16b, only one of these external forces acts on the material 6. Since it is common to
The arrangement posture of the material 6 on the molding table 1 can be compensated for by changing the posture in either direction, and as a result, the required width of the ear rubber is narrowed and the material yield is improved. be able to.

Note that the unvulcanized reinforcing layer 16a as described above,
16b can be formed regardless of whether or not the inner rubber layer 15 is vulcanized, and the reinforcing layers 16a and 16b are vulcanized and molded after the outer rubber layer 17 is formed. Each layer will be bonded to each other.

(Effects of the Invention) Thus, according to the present invention, even if there is some change in the posture of the reinforcing layer forming material placed on the molding table, one variation between rubber-coated reinforcing cords and reinforcing layer formation will be prevented. Separation of the side end surfaces of the material can be reliably prevented, and the durability of the product after vulcanization molding of the rubber sleeve can be significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic plan view illustrating an embodiment of the present invention, and FIG. 2 is an axial cross-sectional view showing a rubber sleeve according to the present invention. 5... Inner rubber layer forming material, 6... Reinforcement layer forming material, 7... Outer rubber layer forming material, 15... Inner rubber layer, 16a, 16b... Reinforcement layer, 17... Outer rubber layer.

Claims (1)

[Claims] 1. When manufacturing a cylindrical rubber sleeve having an inner rubber layer, a reinforcing layer, and an outer rubber layer, the sleeve is made by rubber-coating a plurality of reinforcing cords, has a predetermined width, and has a width in the width direction. By winding a reinforcing layer forming material having an ear rubber of a certain width on at least one side of the reinforcing layer forming material in a spiral manner around the outer circumferential side of an unvulcanized or vulcanized cylindrical inner rubber layer, each of the reinforcing layer forming materials is The position where the side edge of the reinforcing cord located closest to the side edge of the reinforcing layer forming material overlaps the base of the ear rubber, and the position where both end surfaces of the reinforcing layer forming material contact each other. A method for manufacturing a rubber sleeve, comprising forming an unvulcanized reinforcing layer bonded between the rubber sleeve and the rubber sleeve.