Rotary multi-way valve for gas chromatograph

Abstract

The rotary multi-way valve comprises a valve body and a valve head, a plurality of air vents arranged around the center of the valve head are formed in the circumferential direction of the valve head, a rotor is rotatably arranged on one side of the valve head, a plurality of communicating ports corresponding to the air vents are formed in the side, close to the rotor, of the valve head, and the communicating ports are communicated with the air vents. A plurality of vent grooves are formed in the side, close to the valve head, of the rotor, a rotary driving mechanism is arranged at one end of the valve body, and a pressing mechanism used for driving the rotor to be attached to the valve head is arranged on the valve body. The vent grooves in the rotor are matched with the communicating ports in the valve head, communication of the communicating ports is achieved through the vent grooves, communication of the communicating ports can be controlled and switched by controlling rotation of the rotor, control is more convenient, the first sealing face of the rotor and the first sealing face of the valve head are driven by the pressing mechanism to be attached to each other, and sealing between the rotor and the valve head is achieved. And the structure is simple, the machining cost is low, the required machining precision is small, and the product production efficiency is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of chromatographic analysis, in particular to the technical field of rotary multi-way valves for gas chromatographs. Background Art

[0002] Chromatographic analysis is a tool for separating and analyzing multi-component mixtures. It mainly uses the physical properties of substances to separate mixtures, determine each component of the mixtures, and conduct qualitative and quantitative analysis on each component in the mixtures. Chromatography mainly includes gas chromatography and liquid chromatography.

[0003] A gas chromatograph uses gas as the mobile phase carrier gas. When a sample is fed into the injector, it is carried by the carrier gas into the chromatographic column. Due to the differences in the distribution or adsorption coefficients of each component in the sample between the mobile phase gas phase and the stationary phase liquid or solid in the chromatographic column, under the flushing of the carrier gas, each component is repeatedly distributed between the two phases, enabling each component to be separated in the chromatographic column. Then, the detector connected behind the column detects each component in sequence according to the physical and chemical characteristics of the components.

[0004] A gas chromatograph consists of five major systems: a gas path system, an injection system, a separation system, a temperature control system, and a detection and recording system. The injection system includes an injector and a vaporization chamber. The function of the injection system is to instantaneously vaporize a liquid sample before it enters the chromatographic column and then quickly and quantitatively transfer it into the chromatographic column. The size of the injection, the length of the injection time, the vaporization speed of the sample, etc. will all affect the separation effect of chromatography and the accuracy and reproducibility of the analysis results. The injection of liquid samples generally uses a micro syringe, which is now available in both manual and automatic injectors. The injection of gas samples commonly uses a push-pull type multi-way valve or a rotary multi-way valve configured in the gas chromatograph itself for quantitative injection.

[0005] At present, most of the rotary multi-way valves for quantitative injection in common gas chromatographs on the market are imported from abroad. Some domestic multi-way valves also adopt the design schemes of foreign products, and their structures are as shown in the explanatory drawings Figure 14 as follows: The valve core is conical and is rotationally connected to the conical cavity of the valve body through conical surface cooperation. If the conical surface cooperation method is adopted, the conical surface of the valve core must be completely fitted with the conical hole surface of the valve body to ensure the complete sealing of the multi-way valve. This requires extremely high machining requirements for the valve core and the conical hole of the valve body. The existing domestic machining technology is difficult to meet the machining requirements, so the machining qualification rate is very low and the machining cost is relatively high. Moreover, the rotational resistance is large, and it is prone to wear, resulting in air leakage of the multi-way valve and inaccurate data of the gas chromatograph. Therefore, there is an urgent need in the market for a rotary multi-way valve that is completely independently developed and designed in China, is easy to machine, is not prone to wear, and has a long service life. Summary of the Invention

[0006] The object of the present utility model is to solve the problems in the prior art, and a rotary multi-way valve for a gas chromatograph is proposed, providing a multi-way valve with a new structure and a new spool setting method, which has a simple structure, low processing cost and good spool sealing performance.

[0007] To achieve the above object, the present utility model proposes a rotary multi-way valve for a gas chromatograph, including a valve body, a valve head is provided on the valve body, a plurality of air vents are circumferentially provided on the valve head around its center, a rotor is rotatably provided on one side of the valve head, a plurality of communication ports corresponding to the air vents are provided on one side of the valve head close to the rotor, the communication ports are in one-to-one communication correspondence with the air vents, a plurality of air channels are provided on one side of the rotor close to the valve head, the air channels correspond to the communication ports and are used to connect at least two arbitrary communication ports, a rotary driving mechanism is provided at one end of the valve body, and the rotary driving mechanism drives the rotor to rotate forward and backward around its axis to control the air channels to connect different communication ports;

[0008] A first sealing surface is provided on one side of the rotor close to the communication port, a second sealing surface in abutting fit with the first sealing surface is provided in the valve head, the communication port is provided on the second sealing surface, and a pressing mechanism for driving the rotor to fit with the valve head is provided on the valve body.

[0009] Preferably, the pressing mechanism includes a pressing spring, a spring cavity adapted to the pressing spring is provided in the valve body, the pressing spring is provided in the spring cavity, and a top column is provided at one end of the pressing spring close to the rotor, the top column is slidably provided in the spring cavity, a ball adapted to the rotor is provided at one end of the top column close to the rotor, and a rolling groove adapted to the ball is provided on the top column.

[0010] Preferably, a cemented carbide gasket for cooperating with the ball is provided on the contact surface of the rotor with the ball.

[0011] Preferably, the rotor includes a connecting disc body and a ventilation disc body, a rotating shaft protruding towards the driving mechanism is provided at the center of the connecting disc body and is used for cooperating with the driving mechanism, and an installation groove adapted to the ventilation disc body is further provided on the connecting disc body, and the ventilation disc body is detachably provided in the installation groove.

[0012] Preferably, a limit pin synchronously connected with the rotor is further included, a limit groove adapted to the limit pin is provided on the valve body, and the limit pin is movably provided in the limit groove;

[0013] The limit pin in the limit groove has at least a first limit state and a second limit state. When the limit pin is in the first limit state and the second limit state respectively, the ventilation grooves are in states of connecting different communication ports respectively.

[0014] Preferably, the communication ports include a normally open communication port and an intermittent communication port, and the normally open communication port and the intermittent communication port are arranged alternately;

[0015] When the rotor switches between the first limit state and the second limit state, the normally open communication port remains connected to one of the ventilation grooves and is switched to be connected to the intermittent communication ports on both sides through this ventilation groove.

[0016] Preferably, one end of the valve body close to the driving mechanism is provided with a connecting rod for fixedly connecting the valve body and the driving mechanism. A transmission rod is rotatably arranged in the connecting rod, and two ends of the transmission rod are respectively connected to the driving shaft of the driving mechanism and the rotor.

[0017] Preferably, the rotor is provided with a rotating shaft for driving connection with the transmission rod. The transmission rod is provided with a transmission connection sliding groove adapted to the rotating shaft, and the end of the rotating shaft is axially slidable but not rotatable and is arranged in the transmission connection sliding groove.

[0018] Preferably, the rotor and the valve head are made of sapphire material or are provided with a sapphire coating on the surface.

[0019] Preferably, the driving mechanism is a driving motor or a driving cylinder.

[0020] Preferably, the fitting surface of the rotor and the valve head is provided with a sapphire plane, and the fitting surface of the valve head and the rotor is provided with a ceramic spraying coating; or the fitting surface of the rotor and the valve head is provided with a ceramic spraying coating, and the fitting surface of the valve head and the rotor is provided with a sapphire plane.

[0021] Preferably, the pressing mechanism includes a hydraulic chamber arranged in the valve body. The hydraulic chamber is arranged on the side of the rotor away from the valve head and the side of the rotor away from the valve head is arranged in the hydraulic chamber. The hydraulic chamber is filled with a hydraulic medium. The valve body is also provided with a piston sliding chamber communicated with the hydraulic chamber. A piston rod that can move axially along it and is in sealing cooperation with its inner wall is arranged in the piston sliding chamber. The piston rod is adjustably fixed in the piston sliding chamber through a piston fixing component.

[0022] Preferably, the piston fixing assembly is a threaded rod provided at the top of the outer wall of the piston rod. A top cover detachably connected to the piston sliding cavity is provided at the top of the piston sliding cavity. A threaded hole engaged with the threaded rod is provided on the top cover, and a wrench bayonet is provided at the top of the threaded rod.

[0023] Preferably, an adjusting block is provided in the limiting groove. The movable adjusting block is movably provided in the limiting groove along the radial direction of the limiting groove. The limiting pin cooperates with one side of the movable adjusting block. A limiting slide rail is provided at the top or bottom of the limiting groove. A rack arranged along its length direction is provided on the limiting slide rail. A chute adapted to the limiting slide rail is provided on one side of the adjusting block. A gear adapted to the rack is further provided in the adjusting block. One side of the gear extends into the chute and meshes with the rack. A control rod extending outside the adjusting block is provided on the gear.

[0024] Preferably, an external thread of the rod body is provided on the surface of the control rod, and a fixing nut engaged with the external thread of the rod body is provided on the external thread of the rod body. The fixing nut is in abutting cooperation with the outer wall of the adjusting block.

[0025] The beneficial effects of a rotary multi-way valve for a gas chromatograph of the present invention: Through the cooperation of the ventilation grooves on the rotor and the communication ports in the valve head, the communication of each communication port is realized through the ventilation grooves. By controlling the rotation of the rotor, the switching of the communication ports can be controlled, and the control is more convenient. The on-off of multiple communication ports can be controlled simultaneously. Through the pressing mechanism, the first sealing surface of the rotor and the first sealing surface of the valve head are driven to fit with each other to achieve the sealing between the two. The structure is simple, the processing cost is low, the required precision for processing is small, the processing yield is improved, and the production efficiency of the product is greatly improved.

[0026] The features and advantages of the present invention will be described in detail through embodiments in conjunction with the drawings. Description of the Drawings

[0027] Figure 1 is a front three-dimensional structural schematic diagram of a rotary multi-way valve for a gas chromatograph of the present invention.

[0028] Figure 2 is a rear three-dimensional structural schematic diagram of a rotary multi-way valve for a gas chromatograph of the present invention.

[0029] Figure 3 is a top-view structural schematic diagram of a rotary multi-way valve for a gas chromatograph of the present invention.

[0030] Figure 4 is Figure 3 the sectional structural schematic diagram of E-E in

[0031] Figure 5It is a schematic structural diagram of the valve head of a rotary multi-way valve for a gas chromatograph according to the present utility model.

[0032] Figure 6 It is a schematic structural diagram of the rotor of a rotary multi-way valve for a gas chromatograph according to the present utility model.

[0033] Figure 7 It is a schematic structural diagram of the rotor air vent disk body of a rotary multi-way valve for a gas chromatograph according to the present utility model.

[0034] Figure 8 It is a schematic structural diagram when the air vent disk body and the valve head of a rotary multi-way valve for a gas chromatograph according to the present utility model are matched.

[0035] Figure 9 It is a schematic diagram of the cooperation between the communication port 22 and the air vent groove 31.

[0036] Figure 10 It is a schematic sectional structural diagram of Embodiment 3.

[0037] Figure 11 It is a schematic front view structural diagram of Embodiment 4.

[0038] Figure 12 It is a schematic top view structural diagram of the limit groove and the movable adjustment block of Embodiment 4.

[0039] Figure 13 It is a schematic bottom view structural diagram of the movable adjustment block of Embodiment 4.

[0040] Figure 14 It is a schematic structural diagram of the prior art in the background art.

[0041] In the figure: 1 - valve body, 2 - valve head, 3 - rotor, 4 - driving cylinder, 5 - compression spring, 6 - ejector pin, 7 - ball, 8 - limit pin, 11 - limit groove, 12 - connecting rod, 13 - transmission rod, 14 - hydraulic chamber, 15 - piston rod, 16 - movable adjustment block, 21 - air vent, 31 - air vent groove, 32 - connecting disk body, 33 - air vent disk body, 35 - cemented carbide gasket, 131 - transmission connection sliding groove, 321 - rotating shaft, 111 - limit sliding rail, 112 - rack, 141 - piston sliding cavity, 142 - internal thread, 152 - wrench bayonet, 161 - sliding groove, 162 - gear, 163 - control rod, 164 - fixing nut. Detailed implementation manners

[0042] To make the objectives, technical solutions, and advantages of the present utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the scope of the present utility model. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessarily confusing the concepts of the present utility model.

[0043] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the utility model product is usually placed during use. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present utility model. In addition, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, "a plurality" means two or more, unless otherwise specifically defined. The meaning of "several" is one or more, unless otherwise specifically defined. Embodiment 1

[0044] Refer to Figures 1 - 8, a rotary multi-way valve for a gas chromatograph according to the present utility model, comprising a valve body 1, a valve head 2 is provided on the valve body 1, eight air vents 21 are circumferentially arranged on the valve head 2 around its center, a rotor 3 is rotatably provided on one side of the valve head 2, eight communication ports 22 corresponding to the air vents 21 are provided on one side of the valve head 2 close to the rotor 3, the communication ports 22 are in one-to-one communication correspondence with the air vents 21, four air channels 31 are provided on one side of the rotor 3 close to the valve head 2, the air channels 31 correspond to the communication ports 22 and are used to connect two adjacent communication ports 22, each time the air channel 31 connects two communication ports 22, a rotary driving mechanism is provided at one end of the valve body 1, the rotary driving mechanism drives the rotor 3 to rotate forward and backward around its axis to control the air channel 31 to connect different communication ports 22, a first sealing surface is provided on one side of the rotor 3 close to the communication ports 22, a second sealing surface in abutting cooperation with the first sealing surface is provided in the valve head 2, the communication ports 22 are provided on the second sealing surface, and a pressing mechanism for driving the rotor 3 to fit with the valve head 2 is provided on the valve body 1. In this embodiment, through the cooperation of the air channels 31 on the rotor 3 and the communication ports 22 in the valve head 2, the communication of the communication ports 22 is realized through the air channels 31. Controlling the rotation of the rotor 3 can control the switching of the communication ports 22 to be connected. The control is more convenient, and the control of multiple communication ports 22 can be realized at one time. By driving the first sealing surface of the rotor 3 and the first sealing surface of the valve head 2 to fit with each other through the pressing mechanism, the sealing between the two is realized. The structure is simple, the processing cost is low, the required precision for processing is small, and the processing yield is improved, so that the production efficiency of the product is greatly improved.

[0045] Preferably, the driving mechanism is a driving cylinder 4. In another alternative embodiment, the driving mechanism can also be a driving motor, and those skilled in the art can freely select according to needs.

[0046] Refer to Figure 4 , the pressing mechanism includes a pressing spring 5, a spring cavity adapted to the pressing spring 5 is provided in the valve body 1, the pressing spring 5 is provided in the spring cavity, and a top column 6 is provided at one end of the pressing spring 5 close to the rotor 3. The top column 6 is slidably provided in the spring cavity. A ball 7 cooperating with the rotor 3 is provided at one end of the top column 6 close to the rotor 3, and a rolling groove 61 adapted to the ball 7 is provided on the top column 6. The pressing spring 5 is in a compressed state, providing an elastic force, so that the first sealing surface of the rotor 3 and the first sealing surface of the valve head 2 fit with each other, realizing the sealing between the two, making the fit between the rotor 3 and the valve head 2 closer, avoiding air leakage. The setting of the ball 7 can facilitate the cooperation with the rotor 3, reduce the resistance during the rotation of the rotor 3, and make the rotation of the rotor 3 smoother.

[0047] Refer to Figure 4, a threaded plug 17 for abutting against the top of the compression spring 5 is provided at the top of the spring chamber. Refer to Figure 4 , and is detachably installed in the spring chamber through threads.

[0048] Refer to Figure 4 , a cemented carbide gasket 35 for cooperating with the ball 7 is provided on the contact surface of the rotor 3 with the ball 7. The cemented carbide gasket 35 has a high hardness and good anti-deformation performance, preventing the contact surface from being pressed and deformed.

[0049] Preferably, in order to prevent gas leakage when the gas valve works, the valve head 2 must be integrally formed, and the gas valve needs to withstand a high temperature of about 300 °C, so the valve head 2 must be made of a metal material. However, most metal materials are prone to wear, and tiny metal particles will be generated when the rotor 3 and the stator are in frictional contact. The tiny metal particles will follow the gas to be detected into the chromatograph, thus affecting the detection accuracy. To solve the influence caused by this problem, the contact surface of the valve core rotor 3 of this gas valve is a polished sapphire plane, and the surface of the contact surface of the valve head 2 has a ceramic spraying coating with a thickness of 0.5 mm. Since sapphire and ceramic have greater hardness and stronger wear resistance, basically no fine particles will be generated during contact friction. This process greatly improves the hardness of the contact surface of the valve core, makes the valve core more wear-resistant and has a longer service life, and the measurement data of the instrument is also more accurate.

[0050] Preferably, during the processing of the ceramic spraying coating, first spray the ceramic on the metal surface, and then grind the ceramic coating flat enough to ensure the sealing performance of the two-plane fit. Embodiment 2

[0051] Refer to Figure 4 , Figure 6 , the rotor 3 includes a connecting disk body 32 and a ventilation disk body 33. A rotating shaft 321 protruding towards the driving mechanism is provided at the center of the connecting disk body 32 and is used for cooperating with the driving mechanism. An installation groove adapted to the ventilation disk body 33 is also provided on the connecting disk body 32, and the ventilation disk body 33 is detachably arranged in the installation groove. It is convenient to disassemble, maintain and replace the ventilation disk body 33. The rotating shaft 321 passes through the ventilation disk body 33 and the valve head 2, and the connecting disk body 32, the ventilation disk body 33 and the valve head 2 are coaxially connected through the rotating shaft 321.

[0052] Refer to Figure 2, further comprising a limit pin 8 fixedly arranged on the side wall of the rotating shaft 321. A limit groove 11 adapted to the limit pin 8 is provided on the valve body 1. The limit pin 8 is movably arranged in the limit groove 11. The limit pin 8 includes a first limit state and a second limit state in the limit groove 11. The communication port 22 includes a normally open communication port and an intermittent communication port, and the normally open communication port and the intermittent communication port are alternately arranged. When the limit pin 8 is in the first limit state and the second limit state, when the rotor switches between the first limit state and the second limit state, the normally open communication port always remains in communication with one of the ventilation grooves 31 and switches to communicate with the intermittent communication ports on both sides through the ventilation groove 31. When in the first limit state, the ventilation groove 31 connects the normally open communication port with the intermittent communication port on one side thereof. When switched to the second limit state, the ventilation groove 31 connects the normally open communication port with the intermittent communication port on the other side thereof. Repeating in this way, various components are repeatedly distributed between the two phases, so that each component is separated, facilitating subsequent detection and analysis. As Figure 9 shown, in this figure, 1, 3, 5, 7, 9 are used as the normally open communication ports, 2, 4, 6, 8, 10 are used as the intermittent communication ports. 1, 3, 5, 7, 9 are respectively in communication with a corresponding ventilation groove 31. When in position a, it is the first limit state. At this time, 1 is in communication with 2, 3 is in communication with 4, 5 is in communication with 6, 7 is in communication with 8, and 9 is in communication with 10. When the rotor is driven to rotate and switched to position b, it is the second limit state. At this time, the positions of the ventilation grooves 31 are switched, so that 1 is switched to be in communication with 10, 3 is switched to be in communication with 2, 5 is switched to be in communication with 4, 7 is switched to be in communication with 6, and 9 is switched to be in communication with 8.

[0053] Preferably, the rotation angle of the driving cylinder 4 is greater than the limit angle of the limit pin 8 in the limit groove 11, which is more convenient for installation. As long as the limit angle of the limit pin 8 in the limit groove 11 is installed within the rotation angle range of the driving cylinder 4, it can ensure that the gas valve can be normally switched in place.

[0054] Referring to Figure 4 , at one end of the valve body 1 close to the driving mechanism, a connecting rod 12 for fixedly connecting the valve body 1 and the driving mechanism is provided. A transmission rod 13 is rotatably arranged in the connecting rod 12. The two ends of the transmission rod 13 are respectively connected to the driving shaft of the driving mechanism and the rotor 3. A rotating shaft 321 for driving connection with the transmission rod 13 is provided on the rotor 3. A transmission connection sliding groove 131 adapted to the rotating shaft 321 is provided on the transmission rod 13. The end of the rotating shaft 321 is axially slidable but not rotatable and is arranged in the transmission connection sliding groove 131. By providing the transmission connection sliding groove 131 on the transmission rod 13 and axially slidingly arranging the end of the rotating shaft 321 therein, the rotating shaft 321 has a certain axial floating amount, which is convenient for cooperation with the pressing mechanism.

[0055] Refer to Figure 2 , at one end of the transmission rod 13 close to the rotating shaft 321, a pin moving slot communicating with the transmission connection sliding slot 131 is opened. The pin moving slot is arranged along the axial direction of the transmission rod 13, and the limit pin 8 is axially slidably arranged therein. Through the cooperation of the limit pin 8 and the pin moving slot, the rotating shaft 321 and the transmission connection sliding slot 131 are axially slidably connected but not relatively rotatable. The cooperation between the limit pin 8 and the pin moving slot realizes the limitation of the rotation range of the rotor 3, and avoids the misalignment between the ventilation slot 31 and the corresponding communication port 22 caused by the over-rotation of the rotor 3. Embodiment III

[0056] Refer to Figure 10 , on the basis of Embodiment II, the pressing mechanism further includes a hydraulic chamber 14 arranged in the valve body 1. The hydraulic chamber 14 is arranged on the side of the rotor 3 away from the valve head 2 and the side of the rotor 3 away from the valve head 2 is arranged in the hydraulic chamber 14. The hydraulic chamber 14 is filled with a hydraulic medium. A piston sliding chamber 141 communicating with the hydraulic chamber 14 is also arranged in the valve body 1. A piston rod 15 that can axially move and is hermetically matched with its inner wall is arranged in the piston sliding chamber 141. The piston rod 15 is adjustably fixed in the piston sliding chamber 141 through a piston fixing component. In this embodiment, by filling the hydraulic chamber 14 with a hydraulic medium, pressurizing the hydraulic medium through the piston rod 15, and squeezing the rotor 3 through the hydraulic medium, the rotor 3 can better fit the valve head 2, the hydraulic pressure is stronger, the sealing performance between the rotor 3 and the valve head 2 is higher, the top of the rotor 3 can uniformly receive pressure, the force is more uniform, and the pressure in the hydraulic chamber 14 can be adjusted by adjusting the position of the piston rod 15 to meet various use requirements.

[0057] Refer to Figure 10 , a spring chamber is arranged on the lower side of the piston sliding chamber 141 and is communicated with both the piston sliding chamber 141 and the hydraulic chamber 14. The top column 6 and the threaded plug 17 are both provided with channels for the hydraulic medium to pass through, and the hydraulic structure and the spring structure complement each other.

[0058] Refer to Figure 10 , the piston fixing component is a threaded rod 151 arranged on the outer wall top of the piston rod 15. The top of the piston sliding chamber 141 is provided with a top cover 142 detachably connected thereto. A threaded hole meshing with the threaded rod 151 is arranged on the top cover 142, and a wrench bayonet 152 is arranged on the top of the threaded rod 151. The piston rod 15 is fixed in the piston sliding chamber 141 by threads, the fixing is more stable, and it is also convenient to adjust the position of the piston rod 15 in the piston sliding chamber 141, so as to adjust the internal pressure.

[0059] Preferably, a pressure gauge for monitoring the internal pressure of the piston sliding chamber 141 is also arranged on the valve body 1. Embodiment 4

[0060] Referring to Figure 11 、 Figure 12 、 Figure 13 ,an adjusting block 16 is provided in the limiting groove 11. The movable adjusting block 16 is arranged in the limiting groove 11 so as to be movable radially along the limiting groove 11. The limiting pin 8 is matched with one side of the movable adjusting block 16. A limiting slide rail 111 is provided at the top or bottom of the limiting groove 11. A rack 112 is arranged on the limiting slide rail 111 along its length direction. A sliding groove 161 adapted to the limiting slide rail 111 is provided on one side of the adjusting block 16. A gear 162 adapted to the rack 112 is further provided in the adjusting block 16. One side of the gear 162 extends into the sliding groove 161 and meshes with the rack 112. A control rod 163 extending outside the adjusting block 16 is provided on the gear 162. By adjusting the position of the adjusting block 16, the opening size of the limiting groove 11 can be adjusted, and the rotation angle of the rotor 3 can be limited in cooperation with the limiting pin 8. The valve head 2 and the corresponding rotor 3 provided with different numbers of communication ports 22 can be replaced according to requirements. By adjusting the rotation angle of the rotor 3 through the adjusting block 16, different valve heads 2 and rotors 3 can be adapted to meet various usage requirements.

[0061] Referring to Figure 12 、 Figure 13 ,external thread of the rod body is provided on the surface of the control rod 163, and a fixing nut 164 meshing with the external thread of the rod body is provided on the external thread of the rod body. The fixing nut 164 is in abutting fit with the outer wall of the adjusting block 16. Tightening the fixing nut 164 can lock the position of the adjusting block 16 to prevent its displacement.

[0062] Working process of the present utility model:

[0063] During the working process of a rotary multi-way valve for a gas chromatograph of the present utility model, the communication ports 22 of the valve body 1 are respectively connected to each channel. The rotary driving mechanism drives the rotor 3 to rotate forward and backward reciprocally, so that the rotor 3 switches between the first state and the second state. When the rotor switches between the first limiting state and the second limiting state, the normally open communication port is always connected to a ventilation groove 31 and is intermittently connected to the intermittent communication ports on both sides through the ventilation groove 31. When in the first limiting state, the ventilation groove 31 connects the normally open communication port with the intermittent communication port on one side of it. When switching to the second limiting state, the ventilation groove 31 connects the normally open communication port with the intermittent communication port on the other side of it. Repeating like this, various components are repeatedly distributed between two phases, so that each component is separated, which is convenient for subsequent detection and analysis.

[0064] The above embodiments are descriptions of the present utility model, not limitations on the present utility model. Any scheme obtained by simply changing the present utility model belongs to the protection scope of the present utility model.

Claims

1. A rotary multi-way valve for a gas chromatograph, comprising a valve body (1), characterized in that: The valve body (1) is provided with a valve head (2), the valve head (2) is circumferentially provided with a plurality of vents (21) arranged around the center thereof, a rotor (3) is rotatably provided on one side of the valve head (2), a plurality of communication ports (22) corresponding to the vents (21) are provided on a side of the valve head (2) close to the rotor (3), the communication ports (22) are connected and correspond to the vents (21) one by one, a plurality of ventilation grooves (31) are provided on a side of the rotor (3) close to the valve head (2), the ventilation grooves (31) correspond to the communication ports (22) and are used to connect at least two of the communication ports (22), and a rotation drive mechanism is provided at one end of the valve body (1), the rotation drive mechanism drives the rotor (3) to rotate forward and reverse around its axis to control the ventilation grooves (31) to connect different communication ports (22); A first sealing surface is provided on a side of the rotor (3) close to the communication port (22), a second sealing surface is provided in the valve head (2) and contacts with the first sealing surface, the communication port (22) is provided on the second sealing surface, and a clamping mechanism for driving the rotor (3) to fit the valve head (2) is provided on the valve body (1).

2. A rotary multi-way valve for a gas chromatograph as claimed in claim 1, characterized in that: The clamping mechanism comprises a clamping spring (5), a spring cavity adapted to the clamping spring (5) is provided in the valve body (1), the clamping spring (5) is arranged in the spring cavity, and a top column (6) is provided at one end of the clamping spring (5) close to the rotor (3), the top column (6) is slidably arranged in the spring cavity, a ball (7) adapted to the rotor (3) is provided at one end of the top column (6) close to the rotor (3), and a rolling groove (61) adapted to the ball (7) is provided on the top column (6).

3. A rotary multi-way valve for a gas chromatograph as claimed in claim 2, characterized in that: A hard alloy gasket (35) for cooperating with the ball (7) is provided on the contact surface of the rotor (3) with the ball (7).

4. A rotary multi-way valve for a gas chromatograph as claimed in claim 1, characterized in that: The rotor (3) comprises a connecting disc body (32) and a vent disc body (33); a rotating shaft (321) is provided at the center of the connecting disc body (32) and is arranged to protrude in the direction of the driving mechanism and is used to cooperate with the driving mechanism; a mounting groove adapted to the vent disc body (33) is also provided on the connecting disc body (32); the vent disc body (33) is detachably arranged in the mounting groove.

5. A rotary multi-way valve for a gas chromatograph as claimed in claim 1, characterized in that: It also comprises a limit pin (8) synchronously connected to the rotor (3), the valve body (1) is provided with a limit groove (11) adapted to the limit pin (8), and the limit pin (8) is movably arranged in the limit groove (11); The limiting pin (8) includes at least a first limiting state and a second limiting state in the limiting groove (11); when the limiting pin (8) is in the first limiting state and the second limiting state respectively, the ventilation groove (31) is in a state of connecting different communication ports (22).

6. A rotary multi-way valve for a gas chromatograph as claimed in claim 5, characterized in that: The communication port (22) comprises a normal communication port and an intermittent communication port, and the normal communication port and the intermittent communication port are arranged alternately; When the rotor switches between the first limit state and the second limit state, the normally open communication port remains in constant communication with one of the ventilation grooves (31), and switches to communicate with the intermittent communication ports on both sides through the ventilation groove (31).

7. A rotary multi-way valve for a gas chromatograph as claimed in claim 1, characterized in that: A connecting rod (12) for fixedly connecting the valve body (1) to the driving mechanism is provided at one end of the valve body (1) close to the driving mechanism, and a transmission rod (13) is rotatably provided inside the connecting rod (12), and two ends of the transmission rod (13) are respectively connected to a driving shaft of the driving mechanism and the rotor (3).

8. A rotary multi-way valve for a gas chromatograph as claimed in claim 7, characterized in that: The rotor (3) is provided with a rotating shaft (321) for transmission connection with the transmission rod (13); the transmission rod (13) is provided with a transmission connection slide groove (131) adapted to the rotating shaft (321); the end of the rotating shaft (321) is axially slidable but non-rotatable and is arranged in the transmission connection slide groove (131).

9. A rotary multi-way valve for a gas chromatograph as claimed in claim 1, characterized in that: The mating surface of the rotor (3) and the valve head (2) is provided with a sapphire plane, and the mating surface of the valve head (2) and the rotor (3) is provided with a ceramic spray coating; or the mating surface of the rotor (3) and the valve head (2) is provided with a ceramic spray coating, and the mating surface of the valve head (2) and the rotor (3) is provided with a sapphire plane.

10. A rotary multi-way valve for a gas chromatograph as claimed in claim 1, characterized in that: The clamping mechanism comprises a hydraulic chamber (14) arranged in the valve body (1); the hydraulic chamber (14) is arranged on a side of the rotor (3) away from the valve head (2), and the side of the rotor (3) away from the valve head (2) is arranged in the hydraulic chamber (14); the hydraulic chamber (14) is filled with a hydraulic medium; the valve body (1) is also provided with a piston sliding chamber (141) connected to the hydraulic chamber (14); the piston sliding chamber (141) is provided with a piston rod (15) movable along its axial direction and sealingly matched with its inner wall; the piston rod (15) is adjustably fixed in the piston sliding chamber (141) by a piston fixing assembly.

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