JP2003039111A - Pipe bonding structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pipe bonding structure capable of improving bonding strength by upgrading the filling factor of an adhesive. SOLUTION: A pipe 4 is inserted into a bonding hole 6 and in the bonding structure to bond by filling the adhesive 10 between the internal periphery surface of the bonding hole 6 and the outer periphery surface of the pipe 4, a female screwed diameter directional groove 8 is formed on the internal periphery surface of the bonding hole 6.

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pipe joining structure. 2. Description of the Related Art In an intake manifold 1 as shown in FIG.
And a plurality of pipes 4, 4, 4 made of metal or aluminum are provided between the head flange 3 and the head flange 3 attached to the engine side. Is generally performed by brazing or welding, but as shown in FIG. 6, for the purpose of cost reduction and quality improvement, for example, as shown in FIG. As described above, the joining hole 6 is formed in the boss portion 2a of the collector flange 2, and the adhesive 10 is applied to the chamfered portion 5 of the joining hole 6 in a build-up manner, and in this state, the step comes into contact with the step portion 7. The pipe 4 is inserted into the joint hole 6 until the adhesive 10
As shown in FIG. 7, the adhesive 10 is filled in the gap C between the outer peripheral surface of the pipe 4 and the inner peripheral surface of the joining hole 6, and then the adhesive 10 is applied by applying vibration heating. Such a bonding method is disclosed in, for example, JP-A-8-215746. However, in this joining method, a gap C is required, and therefore some positioning mechanism is required. In addition, in order to increase the filling rate of the adhesive 10, heating acoustic vibration is required. Is complicated. [0003] As shown in FIG. 8, for example, a structure in which a joining hole 6 such as a collector flange 2 can be divided into two parts is provided, and an adhesive 10 is applied to an inner peripheral surface of the joining hole 6.
A method of pressing the outer periphery of the pipe 4 in the direction of the arrow and holding the pressed state until the subsequent heating step is completed may be considered, but such a bonding method is established in the case of a specification that cannot be divided. However, it is necessary to perform pressure bonding to each of the divided side and the pipe 4 side while maintaining the relative positional accuracy, and there is a problem that the operation is difficult. SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and it is intended to improve the positioning accuracy and fill the adhesive uniformly and stably to improve the bonding strength. The purpose of the present invention is to provide a pipe joining structure that can be made to join a pipe by inserting a pipe into a joining hole, filling an adhesive between an inner peripheral surface of the joining hole and an outer peripheral surface of the pipe, and joining the pipe. In the structure, a groove is formed in an inner peripheral surface of the joint hole in a radial direction or an axial direction. An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an exploded structural view of the joint structure of the first embodiment. In this example, a joint structure of a pipe 4 to a collector flange 2 of an intake manifold 1 as shown in FIG. 5 is illustrated. It is. A boss 2 a protruding from the collector flange 2 is formed with a joint hole 6, and a small diameter step 7 is formed on the bottom side of the joint hole 6. Is formed with a chamfered portion 5 in an inclined shape. Also, the joint hole 6
A radial groove 8 in the form of a female screw is formed over the entire inner periphery of the inner periphery of the inner periphery. An adhesive 10 of a thermosetting resin is applied to the inner peripheral surface of such a joint hole 6, and in this state, the pipe 4 is inserted into the joint hole 6 in the direction of the arrow from the chamfered part 5 side,
The pipe 4 is inserted until it hits the step portion 7, and the pipe 4 is inserted into the collector flange 2 and the boss portion 2 a via the adhesive 10.
Can be joined. Since the radial groove 8 is formed on the inner peripheral surface of the joint hole 6, the adhesive 10 is stably and uniformly filled between the outer peripheral surface of the pipe 4 and the inner periphery of the joint hole 6. As a result, the contact area of the adhesive 10 is increased by the radial grooves 8, so that the bonding can be efficiently performed with the bonding strength improved. In this example, the gap between the inner peripheral surface of the joining hole 6 and the outer peripheral surface of the pipe 4 can be set as small as possible, and the positioning of the joining hole 6 and the pipe 4 during the joining operation is also facilitated. In addition, by applying heat, the adhesive 10 is cured and a strong bonding state is ensured. Next, FIG. 3 shows a second embodiment. In FIG. 3, a vertical spline-like shape is formed over the entire inner peripheral surface of the joint hole 6 formed in the boss portion 2a of the collector flange 2. An axial groove 9 is formed, and an adhesive 10 is applied to the entire inner peripheral surface of the joint hole 6 in advance, and a pipe 4 is formed.
Is inserted into the joint hole 6 until it comes into contact with the stepped portion 7, and the adhesive 10 can be uniformly filled between the outer peripheral surface of the pipe 4 and the inner periphery of the joint hole 6 and joined. Also in the example, since the axial groove 9 is formed, even if the gap between the outer periphery of the pipe 4 and the inner periphery of the joint hole 6 is set to be extremely small, the pipe 4 is inserted into the joint hole 6 well. Therefore, the positioning accuracy is enhanced, the adhesive 10 can be stably and uniformly filled, the contact area of the adhesive 10 is enlarged, and the bonding strength can be improved. In addition, the pipe 4 with respect to the head flange 3
Also in the joining of the present invention, the joining structure as in the first embodiment or the second embodiment can be adopted. In addition, not only the intake manifold but also various joining structures of metal or aluminum pipes It can be adopted in the scene. According to the present invention, a pipe is inserted into a joint hole,
In a pipe joining structure in which an adhesive is filled between the inner peripheral surface of the joining hole and the outer peripheral surface of the pipe and joined, the inner peripheral surface of the joining hole is
By forming the groove in the radial or axial direction, the gap between the inner circumference of the joint hole and the outer circumference of the pipe is set as small as possible,
The positioning accuracy can be increased, the adhesive is stably and uniformly filled, and the contact area of the adhesive is efficiently enlarged, thereby improving the bonding strength.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view of a first embodiment before a pipe is inserted. FIG. 2 is a cutaway perspective view of a state where a pipe is inserted and joined. FIG. 3 is an exploded perspective view showing a second embodiment before a pipe is inserted. FIG. 4 is a cutaway perspective view of a joined state of pipes. FIG. 5 is a perspective configuration diagram of an intake manifold. FIG. 6 is a cross-sectional configuration diagram before insertion of a pipe having a conventional joint structure. FIG. 7 is a sectional configuration view of a joined state after pipe insertion. FIG. 8 is a cross-sectional configuration diagram showing another conventional bonding structure before bonding. FIG. 9 is a cross-sectional configuration diagram in a joined state. [Description of Signs] 1 Intake manifold 2 Collector flange 2a Boss 3 Head flange 4 Pipe 5 Chamfer 6 Joint hole 7 Step 8 Radial groove 9 Axial groove 10 Adhesive

Claims (1)

Claims: 1. A pipe joining structure in which a pipe is inserted into a joining hole, and an adhesive is filled between an inner peripheral surface of the joining hole and an outer peripheral surface of the pipe to join the pipe. A pipe joining structure, wherein a groove is formed on a peripheral surface in a radial direction or an axial direction.