Air tightness testing device for narrow cavity

Abstract

The utility model relates to an air tightness testing device for a narrow cavity, and belongs to the field of air tightness testing. Comprising an air cylinder, supporting rods, deformable silica gel, a pull ring, supporting rod joints, hinges and vent holes, one ends of the supporting rods are connected with the air cylinder through the hinges, the other ends of the supporting rods are connected with the pull ring through the hinges, the two supporting rods are connected through the supporting rod joints, the vent holes are formed in the pull ring, one end of the deformable silica gel is embedded into the pull ring, and the other end of the deformable silica gel is embedded into an air cylinder shell. When the air cylinder contracts, the pull ring is driven to move back, the pull ring extrudes the deformable silica gel until the deformable silica gel is completely attached to the inner wall of the tested product, the joints of the supporting rod are bent after being subjected to the pulling force until the joints are attached to the inner wall of the deformable silica gel, and certain supporting force is provided for the deformable silica gel after deformation. And after the action is completed, a small-sized closed cavity is formed, and then compressed air required by the test is introduced, so that the airtight test is completed.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the field of air tightness test, specifically relates to a kind of air tightness testing device for narrow cavity. BACKGROUND

[0002] The operation steps of the air tightness test are as follows: firstly, design air tightness tooling for each product, including air tightness joint, gasket and the like, then manually clamp the matched air tightness tooling to the air inlet end of the product, and finally, the equipment is used to introduce compressed gas to test the air tightness. In this process, the design of air tightness tooling and the clamping of tooling become the key factors restricting the production efficiency. On the one hand, the air tightness tooling has poor universality, and a new air tightness tooling needs to be designed for each product, which increases the production time, production cost and management cost of tooling; on the other hand, the clamping efficiency of air tightness tooling is very low, and the full thread of each product needs to be tightened and disassembled manually, which consumes a large amount of unnecessary time, so the efficiency is very low.

[0003] Chinese patent CN202323023562.1 provides a solid rocket engine air tightness detection device, which includes a vacuum pump, a first pneumatic straight pipe joint, an air pipe, a second pneumatic straight pipe joint, a first chuck type pipe joint, an adjusting valve, a clamp type tee joint, a second chuck type pipe joint, a vacuum gauge, a third chuck type pipe joint and an engine connecting tooling. The chuck type pipe joint is used as the air tightness mechanism; Chinese patent CN202323478680.1 provides a solid rocket air tightness detection method, which sets an air tightness test connection hole on the solid rocket plug body, and the air tightness test connection hole is used to install an air tightness joint for testing the air tightness of the solid rocket engine combustion chamber. The air tightness test is performed by connecting the air tightness test joint and the through air tightness test connection hole. In the field of initiating explosive device production, the solid rocket nozzle assembly air tightness test requires no tooling air leakage, and the above-mentioned patents still cannot solve the problems of low air tightness test efficiency and poor tooling universality. UTILITY MODEL CONTENTS

[0004] The utility model aims at overcoming the deficiencies of the prior art, and provides an air tightness test device for narrow cavity. The air cylinder drives the pull ring to move back and forth, and the pull ring extrudes the deformable silica gel during the back-and-forth movement, so that the deformable silica gel is extruded to completely adhere to the inner wall of the test product. The joint of the supporting rod is bent after being subjected to the pulling force until it tightly adheres to the inner wall of the deformable silica gel, thereby providing a certain supporting force for the deformed deformable silica gel. After the operation is completed, a small sealed cavity is formed, and then the compressed air required for the test is introduced to complete the air tightness test.

[0005] The above-mentioned purposes of the utility model are mainly achieved by the following technical solutions:

[0006] The utility model provides a kind of air-tightness testing device for narrow cavity, including air cylinder, support rod, deformable silica gel, pull ring, support rod joint and air hole, support rod one end and air cylinder connect, the other end and pull ring connect, support rod includes two rod structures, two rod structures are connected by support rod joint, air hole is provided on pull ring, deformable silica gel is cylindrical structure, deformable silica gel one end connects air cylinder shell, the other end is connected with pull ring, inner wall surface and support rod are attached.

[0007] It also includes a first hinge and a second hinge, the support rod is connected to the air cylinder through the first hinge, and the support rod is connected to the pull ring through the second hinge.

[0008] The support rod joint is provided with a locking structure to prevent the support rod from rotating more than 180 degrees when it is retracted.

[0009] The air cylinder and the pull ring are provided with grooves, one end of the deformable silica gel is embedded in the groove of the pull ring, and the other end is embedded in the groove of the air cylinder.

[0010] The pull ring is cylindrical, with a through hole in the center, and the travel rod of the air cylinder passes through the through hole and is threadedly connected to the pull ring.

[0011] The deformable silica gel has an inner diameter of φ30-40mm, an outer diameter of φ35-45mm, and a length of 115-125mm.

[0012] The air hole is located 10-20mm from the center of the pull ring, and has a diameter of 4-10mm.

[0013] The air cylinder has a travel of 27-33mm.

[0014] The number of support rods is 3-5.

[0015] The length ratio of the two rod structures of the support rod is 2:2.5-3.5, and the length of the rod structure connected to the air cylinder is longer.

[0016] Compared with the prior art, the utility model has at least the following beneficial effects:

[0017] (1) The utility model uses deformable silica gel as the main air-tight component, which is squeezed to completely adhere to the inner wall of the test product after the air cylinder is retracted, and the joint of the support rod is bent to provide a certain supporting force for the deformed deformable silica gel after being subjected to tension. The air-tight device can be used for air-tight test of different size nozzle assemblies, greatly enhancing its versatility.

[0018] (2), the utility model only needs to control the air cylinder to satisfy the clamping of air tightness device, does not need to tighten and dismount full thread to each product, greatly improves the clamping efficiency of air tightness tooling, and only needs to change the pressure of air cylinder to test for different products and different air pressure test, also greatly improves the adaptability of air tightness device;

[0019] (3), the utility model is mainly used for the air tightness test of solid rocket currently, and the device also has great popularization space, as long as the product of the inner wall is circular to do air tightness test, only needs to select the air tightness device of corresponding size, selects the air cylinder pressure of adaptation, can realize the air tightness test of different products, therefore has great application value. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 The utility model air tightness test device expanded state schematic diagram shows that the utility model air tightness test device contracted state schematic diagram shows that the utility model air tightness test device contracted state structural diagram shows that the utility model mechanism air tightness test device expanded state structural diagram shows that the utility model air tightness test device air cylinder contracted state structural diagram.

[0021] Figure 2 The utility model air tightness test device contracted state schematic diagram shows that the utility model air tightness test device contracted state structural diagram shows that the utility model mechanism air tightness test device expanded state structural diagram shows that the utility model air tightness test device air cylinder contracted state structural diagram.

[0022] Figure 3 The utility model air tightness test device contracted state structural diagram shows that the utility model mechanism air tightness test device expanded state structural diagram shows that the utility model air tightness test device air cylinder contracted state structural diagram.

[0023] Figure 4 The utility model air tightness test device contracted state structural diagram shows that the utility model mechanism air tightness test device expanded state structural diagram shows that the utility model air tightness test device air cylinder contracted state structural diagram.

[0024] Figure 5 The utility model air tightness test device contracted state structural diagram shows that the utility model mechanism air tightness test device expanded state structural diagram shows that the utility model air tightness test device air cylinder contracted state structural diagram. DETAILED DESCRIPTION

[0025] The utility model will be described further in detail in combination with the drawings and specific embodiment:

[0026] As Figure 3 , Figure 4 , and Figure 5As shown, the utility model relates to a kind of air-tightness testing device for narrow cavity, including cylinder 1, support rod 2, deformable silica gel 3, pull ring 4, support rod joint 7, first hinge 8, second hinge 9 and air hole 10;Cylinder 1 stroke is 30mm, can drive support rod 2 movement realizes the air-tight test of inner diameter φ50mm~φ100mm;Support rod 2 has two groups total 8, one group is the support rod 4 close to pull ring 4, another group is the support rod 4 close to cylinder, the length ratio of two groups support rod 2 is 2:3, two groups support rod 2 are connected respectively with support rod joint 7;Support rod 2 is connected with cylinder 1 by first hinge 8, and first hinge 8 is rotatable structure, can realize the 180° rotation of support rod 2.Support rod 2 is connected with pull ring 4 by second hinge 9, and second hinge 9 is rotatable structure, one end is connected with pull ring 4, and the other end is connected with support rod 2, can realize the 180° rotation of support rod 2.Two support rods 2 are support rod joint 7, to prevent support rod 2 from locking when shrinking (rotation angle ≥180°), locking structure is added to support rod joint 7.Again according to the aperture size of the inner wall of product 5 to be tested, select the support rod 2 of corresponding length and the cylinder 1 of adaptation, ensure that support rod 2 has enough deformation space and support force after cylinder 1 shrinks and deformable silica gel 3 is tightly attached to product 5 to be tested, such as Figure 2 As shown, deformable silica gel 3 is cylindrical structure, and the inner diameter is φ30-40mm, and is attached to the outer wall of support rod, and the outer diameter is about φ35-45mm, and the length is 115-125mm, and one end of deformable silica gel 3 is embedded in the groove of pull ring 4, and one end is embedded in the shell groove of cylinder 1;Pull ring 4 is oblate cylindrical, and there is through hole in the middle, and the stroke rod of cylinder 1 passes through the through hole and is connected with external nut washer to realize the sealing and fixing of pull ring 4 and cylinder 1, and air hole 10 is arranged at 10-20mm from the center of pull ring, and air hole 10 can be selected according to demand, and the diameter is φ4-10mm;Pull ring 4 is fixed with the stroke rod of cylinder 1 by thread, and one end of air pipe is connected with equipment to pass into gas, and the other end is fixed into air hole 10, so that air function can be realized.

[0027] The overall movement process of the air-tight device is as follows: Figure 1 、 Figure 2 As shown, air-tightness testing device is inserted into the inner wall of product to be tested, and cylinder 1 is power source, and cylinder 1 is contracted to drive pull ring 4 to move back after being aerated, and second hinge 9 between pull ring 4 and support rod 2, first hinge 8 between support rod and cylinder, and support rod joint 7 between two support rods work simultaneously when pull ring 4 is retracted, so that support rod 2 is deformed from "straight line type" to "V type", from Figure 4 Deform to Figure 5The structure of the support rod joint 7 is moved outward (the diameter of the four support rod joints 7 is increased) to extrude the deformable silica gel 3, provide certain support force for the deformed deformable silica gel, extrude the deformable silica gel 3 to completely adhere to the inner wall of the test product, and finally form the small sealed cavity 6 after the action is completed.

[0028] The above is only the best specific embodiment of the present application, but the protection scope of the present application is not limited to this, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

[0029] The contents not described in detail in the present application are known to those skilled in the art.

Claims

1. A hermetic test device for a small cavity, characterized by: The device comprises a cylinder (1), a support rod (2), a deformable silica gel (3), a pull ring (4), a support rod joint (7) and a ventilation hole (10), one end of the support rod (2) is connected with the cylinder (1), the other end is connected with the pull ring (4), the support rod (2) comprises two rod-shaped structures, the two rod-shaped structures are connected through the support rod joint (7), the pull ring (4) is provided with the ventilation hole (10), the deformable silica gel (3) is a cylindrical structure, one end of the deformable silica gel (3) is connected with the shell of the cylinder (1), the other end is connected with the pull ring (4), and the inner wall surface is attached to the support rod (2).

2. The hermetic test device for a narrow cavity of claim 1, wherein: The device further comprises a first hinge (8) and a second hinge (9), the support rod (2) is connected with the cylinder (1) through the first hinge (8), and the support rod (2) is connected with the pull ring (4) through the second hinge (9).

3. The hermetic test device for a small cavity of claim 1, wherein: The support rod joint (7) is provided with a locking structure to prevent the rotation angle of the support rod (2) from being greater than or equal to 180 degrees when the support rod (2) is retracted.

4. The hermetic test device for a small cavity of claim 1, wherein: The cylinder (1) and the pull ring (4) are provided with grooves on the surfaces, one end of the deformable silica gel (3) is embedded in the groove of the pull ring (4), and the other end is embedded in the groove of the cylinder (1).

5. The hermetic test device for a small cavity of claim 1, wherein: The pull ring (4) is a cylinder, a through hole is arranged at the center of the pull ring (4), and the stroke rod of the cylinder (1) passes through the through hole and is threadedly connected with the pull ring (4).

6. The hermetic test device for a small cavity of claim 4, wherein: The deformable silica gel (3) has an inner diameter of φ30-40mm, an outer diameter of φ35-45mm and a length of 115-125mm.

7. The hermetic test device for a small cavity of claim 1, wherein: The ventilation hole (10) is arranged at a distance of 10-20mm from the center of the pull ring (4), and the ventilation hole (10) has a diameter of 4-10mm.

8. The hermetic test device for a small cavity of claim 1, wherein: The stroke of the cylinder (1) is 27-33mm.

9. The hermetic test device for a small cavity of claim 1, wherein: The number of the support rod (2) is 3-8.

10. The hermetic test device for a small cavity of claim 1, wherein: The length ratio of the two rod-shaped structures of the support rod (2) is 2:2.5-3.5, and the length of the rod-shaped structure connected with the cylinder (1) is longer.

Images