Anti-loosening mechanism of a ferrule type joint

Abstract

The present invention discloses an anti-loosening mechanism for a ferrule-type joint, comprising a ferrule, a nut, a joint body, a ferrule tube, an anti-loosening pin and an indicating retaining ring. The joint body and the nut are provided with threads that match each other. The rear end of the ferrule is provided with a driving outer cone and a plurality of axial grooves are evenly and symmetrically distributed. The inner hole of the nut is provided with a driving inner cone and an axial groove; the front end of the anti-loosening pin is a partial sphere with two parallel planes, and the middle is a rod portion with a diameter the same as the distance between the two planes on the sphere, and the rear end of the rod portion is provided with two axially symmetrical flat-bottomed retaining ring fixing grooves, and the groove bottom plane of the retaining ring fixing groove is parallel to the plane on the sphere. The indicating retaining ring has an inner hole with a diameter matching that of the ferrule tube, and the retaining ring has a special-shaped hole matching the outer shape of the retaining ring fixing groove on the anti-loosening pin. The anti-loosening mechanism of the ferrule-type joint described in the present invention can fix the ferrule nut to prevent loosening, thereby solving the potential safety hazards existing in the prior art.

Description

Technical Field

[0001] The invention relates to the technical field of ferrule type joints, in particular to an anti-loosening mechanism of a ferrule type joint. Background Art

[0002] The compression fittings in ISO8434 and SAE J514 standards are widely used in various hydraulic and pneumatic piping systems and are widely used in many industries such as aircraft, trains, shipping, construction machinery, electricity, and gas.

[0003] The above-mentioned tube fittings push the front edge of the ferrule through the nut, cutting into the ferrule downward along the conical surface inside the fitting body, thereby forming a hard seal between the ferrule and the conical surface inside the fitting body and the outer diameter of the ferrule. The ferrule and the nut are connected through the conical surface, but during use, due to the connection method problems of the ferrule and the nut, coupled with the inevitable vibration, internal pressure shock and other internal and external factors, the ferrule and the nut slide along the contacting conical surface, causing the nut to loosen. Once loosening begins to occur, it will greatly affect the sealing of the entire connection, and may even cause the failure of the entire piping system and have serious safety consequences. Summary of the invention

[0004] 1. Technical issues to be solved

[0005] In view of the deficiencies in the prior art, the present invention provides an anti-loosening mechanism for a ferrule-type joint, which solves the problem of the nut loosening during use.

[0006] (II) Technical solution:

[0007] In order to solve the above problems, the present invention provides the following technical solutions: an anti-loosening mechanism of a ferrule type joint, comprising a ferrule, a nut, a joint body, a ferrule tube, an anti-loosening pin and an indicating retaining ring; the joint body and the nut are provided with mutually matching threads, characterized in that:

[0008] The connector body has a cylindrical hole matching the outer diameter of the sleeve, and an inner conical surface between the end face of the connector body and the cylindrical hole;

[0009] The ferrule is arranged in the nut, the inner hole of the ferrule and the ferrule tube cooperate with each other, the inner wall of the front end of the ferrule has an annular front cutting edge, and there is an annular second cutting edge behind the front cutting edge. The outer surface of the front end of the ferrule is an outer conical surface that is smaller in front and larger in back, and behind the outer conical surface is a first section of cylindrical surface, and behind the first section of cylindrical surface is a second cylindrical surface with a larger diameter than the first cylindrical surface, and between the second cylindrical surface and the rear end surface is a driving outer conical surface that is larger in front and smaller in back. A plurality of axial grooves of the same width that are evenly and symmetrically distributed are opened from the rear end surface to the front end surface, and the front end of the axial groove is connected to a radial cylindrical through hole, and the diameter of this radial cylindrical through hole is larger than the width of the axial groove;

[0010] The inner diameter of the nut through hole matches the outer diameter of the ferrule, the rear of the inner thread of the nut has a driving inner cone surface that matches the driving outer cone surface of the ferrule, and an axial groove is provided on the inner hole of the nut;

[0011] The front end of the anti-loosening pin is a partial sphere with two parallel planes, and behind the sphere is a cylindrical rod, the diameter of the cylindrical rod is equal to the distance between the two planes on the sphere, and the rear end of the rod has two axially symmetrical flat-bottomed retaining ring fixing grooves;

[0012] The inner hole of the indicating retaining ring is closely matched with the outer diameter of the sleeve tube, and the retaining ring is provided with a special-shaped hole which is closely matched with the outer shape of the retaining ring fixing groove on the anti-loosening pin.

[0013] As a preferred embodiment, the angle between the axial grooves at the rear end of the ferrule is 30 degrees or 45 degrees, that is, there are 12 or 8 axial grooves respectively. When the ferrule joint is installed to the torque surge point, it is normally required to tighten the nut by 1 / 6 to 1 / 2 turn. Within this tolerance range, it can be ensured that the axial groove position on the ferrule is aligned with the axial groove position on the nut at one or several positions.

[0014] Preferably, the number of axial grooves in the inner hole of the nut may be 1, or 2-4 evenly distributed, and the width of the axial groove is equal to the width of the axial groove on the ferrule.

[0015] As a preferred embodiment, the diameter of the spherical part of the anti-loosening pin matches the diameter of the radial cylindrical through hole on the ferrule, the diameter of the rod matches the width of the axial groove on the ferrule, and the anti-loosening pin is hardened as a whole. In this way, the anti-loosening pin can be positioned at the cylindrical hole position on the ferrule through the axial groove on the ferrule and the nut, and then the anti-loosening pin is rotated 90 degrees, and the head of the anti-loosening pin can be stuck in the ferrule, preventing the anti-loosening pin from falling out, and the overall hardening treatment ensures the strength of the anti-loosening pin.

[0016] As a preferred embodiment, the number of the special-shaped holes on the indicator retaining ring is consistent with the number of the anti-loosening pins used, and the material of the indicator retaining ring is rubber or plastic. The purpose of using rubber or plastic is to ensure that the indicator retaining ring is stuck on the sleeve to prevent loosening. Secondly, it is also to make the special-shaped holes on the indicator retaining ring easy to be stuck in the retaining ring fixing groove of the anti-loosening pin.

[0017] (III) Beneficial effects

[0018] The beneficial effects of the present invention are as follows: by installing the anti-loosening pin in the axial groove of the ferrule and the axial groove of the nut, the rotation of the nut is prevented, and the potential safety hazard caused by the loosening of the nut is eliminated. The combination of the special-shaped hole on the indicating retaining ring and the retaining ring fixing groove on the anti-loosening pin prevents the rotation of the anti-loosening pin, prevents the anti-loosening pin from falling out, and ensures the reliability of the entire machine. The mechanism is also relatively convenient to disassemble and assemble. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the mechanism of the present invention before installation;

[0020] Figure 2 Schematic diagram of the mechanism of the present invention after installation is completed;

[0021] Figure 3 A front view of the anti-loosening pin 5;

[0022] Figure 4 A top view of the anti-loosening pin 5;

[0023] Figure 5 A schematic diagram of the indicating retaining ring 6, showing the shaped hole 61;

[0024] Figure 6 Sectional view of ferrule 1;

[0025] Figure 7 Card holder Figure 6 The partial top view of the middle C portion shows the axial groove 11 and the radial cylindrical through hole 12 on the ferrule;

[0026] Figure 8 The left side view of the nut 2 shows the axial groove 21 on the nut;

[0027] The following are the descriptions of the reference numerals:

[0028] 1 ferrule, 2 nut, 3 connector body, 4 ferrule, 5 anti-loosening pin, 6 indicator ring DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described below in conjunction with specific implementation methods.

[0030] See also Figure 1 The schematic diagram of the relative positions of the parts before the ferrule is installed shows that the present invention includes a connector body 3 for connecting with the ferrule 4, an indicator ring 6, a locking pin 5, a ferrule 1, and a nut 2 for driving and tightening the ferrule. Figure 1The schematic diagram of the relative positions of the ferrule 1, nut 2, connector body 3 and ferrule 4 before the installation of the ferrule is shown. After the ferrule 1 is pre-installed, when the nut 2 is tightened to the torque surge point, the front end of the ferrule 2 cuts into the outer wall of the ferrule 4, and the nut 2 is continued to be tightened. Within the tightening tolerance range of 1 / 6 to 1 / 2 turn, it can be ensured that at a certain position, the position of the axial groove 11 on the ferrule 1 is aligned with the position of the axial groove 21 on the nut 2, and the two flat surfaces 51 of the ball head of the anti-loosening pin 5 are fitted with the side of the axial groove 21 on the nut 2, and are inserted into the axial groove until they reach the radial cylindrical through hole 12 at the bottom of the axial groove 11 of the ferrule 1, and then the anti-loosening pin is rotated 90 degrees so that the ball head 52 of the anti-loosening pin 5 is stuck in the radial cylindrical through hole 12 of the ferrule 1, and then the special-shaped hole 61 of the indicating retaining ring 6 is stuck in the retaining ring fixing groove 53 of the anti-loosening pin 5, and the whole installation process is completed. Figure 2 When disassembling, just disengage the indicating retaining ring 6, rotate the anti-loosening pin 5 90 degrees and then pull it out, and the whole mechanism can be disassembled normally.

[0031] Specific working principle:

[0032] The invention discloses a ferrule type joint anti-loosening mechanism, comprising a joint body 3 for connecting with a ferrule tube 4, an indicating retaining ring 6, an anti-loosening pin 5, a ferrule 1, and a nut 2 for driving and pressing the ferrule. When the mechanism is installed, Figure 2 As shown, the middle of the ferrule 1 is arched, and an axial thrust is generated on the inner conical surface of the nut 2 in the direction of the outer conical surface. If the system has internal or external factors such as vibration or internal pressure shock that may cause the nut to loosen, the nut 2 tends to loosen and begins to rotate counterclockwise in the loosening direction. This counterclockwise rotation will drive the ferrule 1 to rotate counterclockwise in the same direction through the anti-loosening pin 5. Since the front end of the ferrule 1 cuts into the ferrule tube 4, the friction at the cut-in point is very large and cannot rotate, resulting in a clockwise torque inside the ferrule 1. This torque direction offsets the torque that causes the nut 2 to loosen, thereby preventing the nut from loosening.

[0033] The above are only preferred embodiments of the present invention. It should be noted that the above preferred embodiments should not be regarded as limiting the present invention, and the protection scope of the present invention should be based on the scope defined by the claims. For ordinary technicians in this technical field, several improvements or modifications can be made without departing from the spirit and scope of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. An anti-loosening mechanism for a ferrule type joint, comprising a ferrule, a nut, a joint body, a ferrule tube, an anti-loosening pin and an indicating retaining ring; the joint body and the nut are provided with mutually matching threads, characterized in that: The connector body has a cylindrical hole matching the outer diameter of the sleeve, and an inner conical surface between the end face of the connector body and the cylindrical hole; The ferrule is arranged in the nut, the inner hole of the ferrule and the ferrule tube cooperate with each other, the inner wall of the front end of the ferrule has an annular front cutting edge, and there is an annular second cutting edge behind the front cutting edge. The outer surface of the front end of the ferrule is an outer conical surface with a smaller front and a larger rear, and behind the outer conical surface is a first section of cylindrical surface, and behind the first section of cylindrical surface is a second cylindrical surface with a larger diameter than the first cylindrical surface, and between the second cylindrical surface and the rear end surface is a driving outer conical surface with a larger front and a smaller rear, and a plurality of axial grooves of the same width are opened from the rear end surface to the front end surface direction, which are evenly and symmetrically distributed, and the front end of the axial groove on the ferrule is connected to the radial cylindrical through hole, and the diameter of this radial cylindrical through hole is larger than the width of the axial groove on the ferrule; The inner diameter of the nut through hole matches the outer diameter of the ferrule, the rear of the inner thread of the nut has a driving inner cone surface that matches the driving outer cone surface of the ferrule, and an axial groove is provided on the inner hole of the nut; The front end of the anti-loosening pin is a partial sphere with two parallel planes, and behind the sphere is a cylindrical rod, the diameter of the cylindrical rod is equal to the distance between the two planes on the sphere, and the rear end of the rod has two axially symmetrical flat-bottomed retaining ring fixing grooves; The inner hole of the indicating retaining ring is closely matched with the outer diameter of the sleeve, and the retaining ring is provided with a special-shaped hole which is closely matched with the outer shape of the retaining ring fixing groove on the anti-loosening pin; The middle part of the ferrule is arched, and an axial thrust is generated on the inner conical surface of the nut in the direction of the outer conical surface. When the nut loosens, the nut tends to loosen and begins to rotate counterclockwise in the loosening direction. This counterclockwise rotation will drive the ferrule to rotate counterclockwise in the same direction through the anti-loosening pin. Since the front end of the ferrule cuts into the ferrule tube and cannot rotate, a clockwise torque is generated inside the ferrule. This torque direction offsets the torque that causes the nut to loosen, thereby preventing the nut from loosening. The number of axial grooves in the inner hole of the nut is 1, or 2-4 evenly distributed, and the width of the axial groove on the nut is equal to the width of the axial groove on the ferrule; The diameter of the spherical part of the anti-loosening pin matches the diameter of the radial cylindrical hole on the ferrule, the diameter of the rod matches the width of the axial groove on the ferrule, and the anti-loosening pin is hardened as a whole; The combination of the special-shaped hole on the indicating retaining ring and the retaining ring fixing groove on the anti-loosening pin prevents the anti-loosening pin from rotating and falling out, thereby ensuring the reliability of the entire machine.

2. The anti-loosening mechanism of a ferrule type joint according to claim 1, characterized in that: The angles between the axial grooves at the rear end of the ferrule are 30 degrees or 45 degrees.

3. The anti-loosening mechanism of a ferrule type joint according to claim 1, characterized in that: The number of the special-shaped holes on the indicating retaining ring is consistent with the number of the anti-loosening pins used, and the material of the indicating retaining ring is rubber or plastic.

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