Connecting structure of valve rod and transmission rod

Abstract

The utility model discloses a valve rod and transmission rod connecting structure which comprises a valve rod and a transmission rod, the valve rod is designed in a three-section mode and is provided with a key groove, and the transmission rod is designed in a three-section mode and is provided with an inverted-U-shaped window. The valve rod and the transmission rod are connected through threads and fixed through a square key and a set screw, the key groove and the inverted-U-shaped window are aligned in position, the square key is fixedly installed in the key groove of the valve rod, a counter bore is formed in the square key, and the set screw is fixedly installed in the counter bore of the square key. The connecting structure of the valve rod and the transmission rod not only has the advantages of a cylindrical pin connecting mode and a clamping block connecting mode, but also can meet the transmission modes of a thrust type actuator and a multi-rotation type actuator at the same time, and has the advantages of being compact in structure, easy to machine, good in pressure bearing performance, safe, reliable and more durable in use, convenient to maintain and the like.

Description

Technical Field

[0001] This utility model relates to a connection structure, and more particularly to a connection structure between a valve stem and a transmission rod. Background Technology

[0002] Valves are indispensable fluid control equipment in various sectors of the national economy, including petroleum, chemical, power plants, long-distance pipelines, shipbuilding, nuclear industry, various cryogenic engineering projects, aerospace, and offshore oil extraction. The development and needs of industries such as petroleum, natural gas, and LNG have driven the growth of the valve industry.

[0003] Gate valves and globe valves, among other straight-stroke valves, are widely used in my country in industries such as petroleum refining, long-distance pipelines, chemicals, papermaking, pharmaceuticals, water conservancy, power, municipal engineering, and steel, playing a crucial role in the national economy. For straight-stroke valves with electric, hydraulic, or pneumatic actuators, the actuator drive rod is connected to the valve stem using a cylindrical pin connection or a clamping block connection.

[0004] The cylindrical pin connection requires machining a through pin hole on the valve stem to install the cylindrical pin for transmission. However, machining a pin hole on the valve stem will inevitably affect the strength of the valve stem, and the cylindrical pin will often break during long-term use, leading to valve failure, inability to open and close normally, and even personal safety accidents.

[0005] The clamping block connection requires adding a clamping block between the valve stem and the transmission rod. The clamping block is difficult to manufacture, and its machining accuracy directly affects the coaxiality of the valve stem and the transmission rod. Furthermore, the clamping block is prone to loosening during long-term use, which can lead to valve failure, inability to open and close normally, and even personal safety accidents. Utility Model Content

[0006] The technical problem to be solved by this utility model is to provide a valve stem and transmission rod connection structure that not only combines the advantages of cylindrical pin connection and clamp block connection, but also meets the transmission type of thrust type and multi-turn actuator, and has the characteristics of compact structure, simple processing, good pressure resistance, safe and reliable use, more durable, and convenient maintenance.

[0007] The technical solution adopted by this utility model to solve the above-mentioned technical problems is to provide a valve stem and transmission rod connection structure, including a valve stem and a transmission rod. The valve stem is designed in three sections and is provided with a keyway, and the transmission rod is designed in three sections and is provided with an inverted U-shaped window. The valve stem and the transmission rod are connected by threads and fixed by a square key and a set screw. The keyway and the inverted U-shaped window are aligned. The square key is fixedly installed in the keyway of the valve stem. The square key is provided with a countersunk hole, and the set screw is fixedly installed in the countersunk hole of the square key.

[0008] Furthermore, the first section of the valve stem is the valve stem and valve core connection section, the second section is the valve stem keyway section, and the third section is the valve stem threaded section; the valve stem keyway section is provided with a keyway, the keyway is provided with an internal threaded hole, and the valve stem threaded section is provided with an external thread.

[0009] Furthermore, the first section of the transmission rod is the connection section between the valve stem and the transmission rod, the second section is the threaded section of the transmission rod, and the third section is the connection section between the transmission rod and the actuator; the connection section between the valve stem and the transmission rod is provided with an inverted U-shaped window, and the threaded section of the transmission rod is provided with an internal thread that is compatible with the threaded section of the valve stem.

[0010] Furthermore, the valve stem keyway section is provided with two keyways distributed at 180 degrees.

[0011] Furthermore, the set screw is coated with adhesive.

[0012] Furthermore, the transmission rod and actuator connection section are connected to a thrust actuator or a multi-turn actuator.

[0013] Compared with the prior art, the present invention has the following advantages: The valve stem and transmission rod connection structure provided by the present invention not only combines the advantages of cylindrical pin connection and clamp block connection, but also meets the transmission type of thrust type and multi-turn actuator. In addition, it has the characteristics of compact structure, simple processing, good pressure resistance, safe and reliable use, greater durability, and convenient maintenance. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the connection structure between the valve stem and the transmission rod of this utility model;

[0015] Figure 2 This is a schematic diagram of the valve stem structure of this utility model;

[0016] Figure 3 This is a schematic diagram of the transmission rod structure of this utility model;

[0017] Figure 4 This is a schematic diagram of the square key structure of this utility model;

[0018] Figure 5 This is a schematic diagram of the installation process of the valve stem and transmission rod of this utility model.

[0019] The markings in the diagram are as follows: 1. Valve stem; 2. Transmission rod; 3. Square key; 4. Set screw; 100. Threaded section of valve stem; 101. Keyway section of valve stem; 102. Connection section between valve stem and valve core; 105. Threaded section of transmission rod; 106. Connection section between valve stem and transmission rod; 107. Inverted U-shaped window; 108. Countersunk hole; 109. Connection section between transmission rod and actuator. Detailed Implementation

[0020] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0021] Figure 1 This is a schematic diagram of the connection structure between the valve stem and the transmission rod of this utility model.

[0022] Please see Figure 1 The valve stem and transmission rod connection structure provided by this utility model includes a valve stem 1 and a transmission rod 2. The valve stem 1 is a three-section design with a keyway 103, and the transmission rod 2 is a three-section design with an inverted U-shaped window 107. The valve stem 1 and the transmission rod 2 are connected by threads and fixed by a square key 3 and a set screw 4. The keyway 103 and the inverted U-shaped window 107 are aligned. The square key 3 is fixedly installed in the keyway 103 of the valve stem 1. The square key 3 is provided with a countersunk hole 108, and the set screw 4 is fixedly installed in the countersunk hole 108 of the square key 3.

[0023] like Figure 2 The schematic diagram of the valve stem structure of this utility model is shown. The left half is a cross-sectional view of the valve stem. The valve stem 1 is a three-section design. The first section is the valve stem and valve core connection section 102. The second section is the valve stem keyway section 101, which is designed with two keyways 103 distributed at 180 degrees. The two keyways 103 are designed with internal threaded holes 104. The third section is the valve stem threaded section 100, which is designed with external threads.

[0024] like Figure 3 The schematic diagram of the transmission rod structure of this utility model is shown. The left half is a half-sectional view of the transmission rod. The transmission rod 2 is a three-section design. The first section is the connection section 106 between the valve stem and the transmission rod, which is designed with an inverted U-shaped window 107. The second section is the threaded section 105 of the transmission rod, which is designed with internal threads and is adapted to the threaded section 100 of the valve stem. The third section is the connection section 109 between the transmission rod and the actuator, which is adapted to the actuator.

[0025] like Figure 4 The schematic diagram of the square key structure of this utility model is shown. The square key 3 is designed with a countersunk hole 108 for installing the set screw 4.

[0026] like Figure 5 The diagram shows the installation process of the valve stem and transmission rod of this utility model. The external thread section of the valve stem 1 is screwed onto the internal thread section of the transmission rod 2. Before the internal and external threads are fully engaged, the positions of the keyway 103 and the inverted U-shaped window 107 are manually adjusted by rotation to align them, allowing the square key 3 to pass smoothly through the inverted U-shaped window 107 and be installed in the keyway 103. The vertical position of the square key 3 is adjusted so that the countersunk hole 108 on the square key 3 matches the internal threaded hole designed in the keyway 103. The set screw 4 is fixedly installed in the countersunk hole 108 of the square key 3. Loctite glue can be used to prevent loosening and falling off when installing the set screw 4.

[0027] In summary, the valve stem and transmission rod connection structure provided by this utility model combines the advantages of cylindrical pin connection and clamp block connection, overcoming their disadvantages. It can simultaneously meet the transmission requirements of thrust type and multi-turn actuator, and features compact structure, simple processing, good pressure resistance, safe and reliable operation, durability, and convenient maintenance.

[0028] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications and improvements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the claims.

Claims

1. A valve stem and drive rod connection structure comprising a valve stem (1) and a drive rod (2), characterized in that, The valve stem (1) is a three-section design and is provided with a key groove (103), the transmission rod (2) is a three-section design and is provided with a reverse U-shaped window (107); the valve stem (1) and the transmission rod (2) are connected through threads and are fixed by a square key (3) and a set screw (4), the positions of the key groove (103) and the reverse U-shaped window (107) are aligned, the square key (3) is fixedly installed in the key groove (103) of the valve stem (1), the square key (3) is provided with a counterbore (108), and the set screw (4) is fixedly installed in the counterbore (108) of the square key (3).

2. The valve stem and drive rod coupling structure as defined in claim 1 wherein, The first section of the valve stem (1) is a valve stem and valve core connecting section (102), the second section is a valve stem key groove section (101), and the third section is a valve stem threaded section (100); the valve stem key groove section (101) is provided with a key groove (103), the key groove (103) is provided with an internal thread hole (104), and the valve stem threaded section (100) is provided with an external thread.

3. The valve stem and drive rod coupling structure as defined in claim 2 wherein, The first section of the transmission rod (2) is a valve stem and transmission rod connecting section (106), the second section is a transmission rod threaded section (105), and the third section is a transmission rod and actuator connecting section (109); the valve stem and transmission rod connecting section (106) is provided with a reverse U-shaped window (107), the transmission rod threaded section (105) is provided with an internal thread and is matched with the valve stem threaded section (100).

4. The valve stem and drive rod coupling structure of claim 2 wherein, The valve stem key groove section (101) is provided with two key grooves (103) distributed at 180 degrees.

5. The valve stem and drive rod coupling structure as defined in claim 1 wherein, The set screw (4) is coated with glue.

6. The valve stem and drive rod coupling structure as defined in claim 1 wherein, The transmission rod and actuator connecting section (109) is connected with a push type actuator or a multi-rotation type actuator.

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