Thermal cycler

Abstract

The invention relates to a thermal cycler, and discloses an automatically controlled thermal cycler which comprises a box body, and a lifting mechanism (2), a fixed plate (3) and a control unit are arranged in the box body; the control unit automatically controls the lifting mechanism (2) to ascend and descend, the fixing plate (3) is connected with the lifting mechanism (2), and the fixing plate (3) ascends and descends along with the lifting mechanism (2). An in-out mechanism (1) is arranged on the fixed plate (3); the control unit automatically controls in and out of the in-out mechanism (1); a sample mechanism (4) is connected above the in-out mechanism (1); when the lifting mechanism (2) acts, the sample mechanism (4) can perform lifting operation, and when the in-out mechanism (1) acts, the sample mechanism (4) performs in-out operation. According to the invention, the sample mechanism can be automatically lifted, and the operation is convenient; and the working safety and the accuracy of experimental data are further ensured.

Description

Technical Field

[0001] The present invention relates to a thermal cycler, and particularly to an automatically controlled thermal cycler. Background Art

[0002] Biochemical reactions usually need to be carried out under the condition of precisely controlling the temperature of the reaction liquid components. For example, the reaction liquid components of polymerase chain reaction (PCR) are placed in a sample tube. The sample tube is usually made of heat-conductive plastic or other materials, covered and sealed to prevent evaporation, and then the sample tube is inserted into a sample well dug on a sample holder. The sample holder is usually made of metal or other heat-conductive materials through cutting or other forming processing techniques. By adding a heating and cooling device, the temperature of the sample holder is controlled, and through heat transfer, the temperature of the reaction liquid in the sample tube in the sample holder is controlled.

[0003] As described in the prior art CN201510844750.1 for the thermal cycler, the operation of taking and placing the sample tube on the sample holder is manually operated by the experimenter. This makes the operation steps numerous, the operation time long, and the degree of automation low. During the opening and closing process of the upper cover of the chassis, the operator's hand is likely to touch the hot cover at a relatively high temperature, causing burns and posing certain work safety hazards. Therefore, hiding the hot cover inside the chassis can effectively avoid work safety hazards.

[0004] The prior art cannot ensure the consistency of the pressure applied to the top of the 0.1ML or 0.2ML sample tube and the precise control of the pressing force when the hot cover presses different specifications of sample tubes. Summary of the Invention

[0005] In view of the problems in the prior art that the operation of the thermal cycler requires manual operation by the operator, the operation is complex, and it is difficult to ensure work safety, etc., the present invention provides a thermal cycler.

[0006] To solve the above technical problems, the present invention is solved by the following technical solutions:

[0007] A thermal cycler includes a box body, in which a lifting mechanism, a fixing plate and a control unit are provided; the control unit automatically controls the lifting of the lifting mechanism, the fixing plate is connected to the lifting mechanism, and the fixing plate rises and falls with the lifting operation of the lifting mechanism.

[0008] Preferably, an inlet and outlet mechanism is provided on the fixing plate, and a sample mechanism is connected to the inlet and outlet mechanism; the control unit automatically controls the inlet and outlet of the inlet and outlet mechanism; when the lifting mechanism acts, the sample mechanism will perform a lifting operation, and when the inlet and outlet mechanism acts, the sample mechanism performs an inlet and outlet operation.

[0009] Preferably, the lifting mechanism includes a gear fixing plate, a lifting motor, and a lead screw; a gear is provided on the fixed gear plate, the gear includes a driving gear and a driven gear set, and the lead screw is connected to the driven gear set; when the lifting motor starts, it drives the driving gear to rotate, drives the driven gear set and the lead screw to rotate, and causes the lead screw nut and the connected fixing plate to lift along the lead screw.

[0010] Preferably, the driven gear set includes a first driven gear and a second driven gear, and the lead screw is connected to the first driven gear, and the second driven gear is located in the middle of the first driven gear; when the lifting motor starts, it drives the driving gear to drive the rotation of the lead screw and the lifting operation of the lead screw nut, and the driving gear drives the first driven gear that meshes with the driving gear, and coordinates the movement of the first driven gear through the second driven gear.

[0011] Preferably, the driven gear set includes a first driven gear, a second driven gear, and an intermediate driven gear. The first driven gears are located at the four corners of the lifting mechanism, and the second driven gears are evenly distributed in the middle of the lifting mechanism (2); the intermediate driven gear is located in the middle of the second driven gears of the lifting mechanism, and is used to transmit the movement of the second driven gears and coordinate the movement of the first driven gears; the lead screw is connected to the first driven gear; when the lifting motor starts, it drives the driving gear to drive the rotation of the lead screw and the lifting operation of the lead screw nut, the driving gear drives the first driven gear close to the driving gear, the first driven gear drives the second driven gear, and coordinates the movement of the first driven gear and the second driven gear through the intermediate driven gear

[0012] Preferably, the feeding and discharging mechanism includes a rack fixing plate, a feeding and discharging mechanism gear, and a feeding and discharging motor; the feeding and discharging mechanism gear meshes with the rack, and drives the feeding and discharging gear to rotate through the feeding and discharging motor, thereby driving the rack to move; guide rails are provided on both sides of the rack fixing plate, and sliders are connected to the guide rails, and the sliders slide along the guide rails; the feeding and discharging motor is fixedly connected to the fixing plate, and a rack is provided at the bottom of the rack fixing plate; and the feeding and discharging mechanism gear meshes with the rack; the rack converts the rotation into a linear motion in the front and back directions through the cooperation with the feeding and discharging mechanism gear; the upper part of the rack fixing plate is connected to the sample mechanism, and the sample mechanism performs a linear motion in the front and back directions as the rack fixing plate moves back and forth.

[0013] Preferably, the sample mechanism includes a heat dissipation unit and a sample stage; the heat dissipation unit includes a heat dissipation bracket, and a radiator is provided on the heat dissipation bracket, and the sample stage is located on the heat dissipation unit.

[0014] Preferably, the heat dissipation of the radiator 423 is cooled by air flow or liquid flow.

[0015] Due to the adoption of the above technical solutions, the present invention has remarkable technical effects:

[0016] The lifting mechanism in the thermal cycler of the present invention mainly consists of 1 lifting motor, 1 set of radiator fixing plate assemblies, 10 gears of different sizes, and 4 lead screws. The movement of the lifting mechanism: First, start the motor, and the motor shaft starts to rotate to drive the driving gear. The model of this driving gear is DS1-20 plastic gear. When it starts to rotate, it drives the first driven gear, the second driven gear, and the intermediate driven gear to start rotating. The first driven gear is a DS1-40 plastic gear evenly distributed at the four corners. The second driven gear is evenly arranged with 4 DS1-40 plastic gears and 1 intermediate driven gear DS1-80 plastic gear to transmit motion and coordinate the simultaneous uniform rotation of the plastic gears at the four corners. The four lead screws are fixed on the first driven gears at the four corners and restrict the up and down movement of the lead screws. Thus, the four lead screws will simultaneously start to rotate with the first driven gear plastic gears. Through the cooperation of the nuts fixed in the guide rail fixing plate assembly and the lead screws, the entire sample mechanism moves up and down in a straight line at a uniform speed.

[0017] The feeding and discharging mechanism of the present invention mainly consists of 1 feeding and discharging motor, 1 feeding and discharging mechanism gear, 1 rack, 2 sets of guide rail assemblies, and 1 set of rack fixing plate assemblies. First, start the feeding and discharging motor, and the motor shaft of the feeding and discharging motor starts to rotate to drive the feeding and discharging mechanism gear to rotate. The guide rails are fixed on the rack fixing plate, the sliders are fixed on the guide rail fixing plate, the gears are fixed on the guide rail fixing plate, and through the cooperation of the rack and the gears, the rack will move in a straight line back and forth. The rack and the sample mechanism are simultaneously fixed on the rack fixing plate, so that the entire sample mechanism moves in a straight line in the front and back directions.

[0018] The structure of the thermal cycler designed by the present invention can automatically perform lifting and feeding and discharging operations without manual operation, and its operation is convenient. It further ensures the safety of work and the accuracy of experimental data. Description of the Drawings

[0019] Figure 1 is the structural diagram of the thermal cycler of the present invention.

[0020] Figure 2 is the structural diagram of the thermal cycler in the pulled-out state of the present invention;

[0021] Figure 3 is the internal structure of the thermal cycler of the present invention Figure 1 ;

[0022] Figure 4 is the internal structure of the thermal cycler of the present invention Figure 2 ;

[0023] Figure 5 is the structure of the heat dissipation unit of the present invention Figure 1 ;

[0024] Figure 6is the heat dissipation unit structure of the present invention Figure 2 ;

[0025] Figure 7 is the drive circuit diagram of the inlet and outlet motor of the present invention;

[0026] Figure 8 is the drive circuit diagram of the lifting motor of the present invention;

[0027] Figure 9 is the control unit circuit diagram of the present invention;

[0028] Figure 10 is the structure diagram of the lifting mechanism in Embodiment 1 of the present invention;

[0029] Figure 11 is the structure diagram of the lifting mechanism in Embodiment 4 of the present invention;

[0030] Figure 12 is the structure diagram of Embodiment 1 of the present invention.

[0031] Among them, 1 - inlet and outlet mechanism, 2 - lifting mechanism, 3 - fixing plate, 4 - sample mechanism, 5 - display unit, 21 - lifting motor, 22 - gear, 23 - lead screw, 24 - fixed gear plate, 221 - driving gear, 222 - first driven gear, 223 - second driven gear, 224 - intermediate driven gear, 11 - rack fixing plate, 12 - inlet and outlet mechanism gear, 13 - inlet and outlet motor, 14 - rack, 15 - slider, 42 - heat dissipation unit, 41 - sample stage, 43 - temperature control board, 421 - heat dissipation bracket, 422 - heat dissipation support frame, 423 - radiator, 424 - cooling fan. Detailed implementation manners

[0032] The present invention will be further described in detail below with reference to the drawings and embodiments.

[0033] Embodiment 1

[0034] A thermal cycler, Figure 12 which includes a box body, and a lifting mechanism 2, a fixing plate 3 and a control unit are arranged in the box body; the control unit automatically controls the lifting of the lifting mechanism 2, the fixing plate 3 is connected to the lifting mechanism 2, and the fixing plate 3 moves up and down along with the lifting operation of the lifting mechanism 2; a sample mechanism 4 is arranged on the fixing plate 3, and a movable box cover is arranged on the side of the box body, and the movement of the sample mechanism 4 is operated by the movement of the box cover.

[0035] Embodiment 2

[0036] On the basis of Embodiment 1, Figure 1In this embodiment, an inlet / outlet mechanism 1 is provided on the fixed plate, and a sample mechanism 4 is connected to the inlet / outlet mechanism 1; the control unit automatically controls the inlet and outlet of the inlet / outlet mechanism 1; when the lifting mechanism 2 operates, the sample mechanism 4 will perform a lifting operation, and when the inlet / outlet mechanism 1 operates, the sample mechanism 4 performs an inlet / outlet operation. In this embodiment, the control unit can automatically control the inlet / outlet mechanism and the lifting mechanism. Among them Figure 2 Figure Figure 2 is a structural diagram of the extraction state of the inlet / outlet mechanism 1 of the thermal cycler.

[0037] Figure 10 In this embodiment, the lifting mechanism 2 includes a gear fixed plate 24, a lifting motor 21 and a lead screw 23; a gear 22 is provided on the fixed gear plate 24, and the gear 22 includes a driving gear 221 and a driven gear group, and the lead screw 23 is connected to the driven gear group; when the lifting motor 21 starts, it drives the driving gear 221 to rotate, drives the driven gear group 22 and the lead screw 23 to rotate, and causes the lead screw nut and the connected fixed plate 3 to move up and down along the lead screw 23.

[0038] In Figure 10 this embodiment, there are 5 driven gears, including four first driven gears 222 and an intermediate driven gear 224. The first driven gears 222 are driven by the driving gear 221, and the first driven gears 222 are located at the four corners inside the box. There are four lead screws 23, and the lead screws 23 are connected to the first driven gears 222. When the lifting motor 21 starts, it drives the driving gear 221 to drive the driven gear group 22 and the lead screw 23 to rotate, causing the lead screw nut and the connected fixed plate 3 to move up and down and rotate along the lead screw 23. The driving gear 221 drives the first driven gear 222 close to the driving gear 221, and the first driven gear 222 coordinates the movement of the first driven gear 222 through the intermediate driven gear 224.

[0039] Figure 4 In this embodiment, the inlet / outlet mechanism 1 includes a rack fixed plate 11, an inlet / outlet mechanism gear 12 and an inlet / outlet motor 13; the inlet / outlet mechanism gear 12 meshes with the rack 14, and the inlet / outlet gear 22 is driven to rotate by the inlet / outlet motor 13, thereby driving the rack 14 to move; guide rails are provided on both sides of the rack fixed plate 11, and a slider 15 is connected to the guide rails, and the slider 15 slides along the guide rails; the inlet / outlet motor 13 is fixedly connected to the fixed plate 3, and a rack 14 is provided at the bottom of the rack fixed plate 11; and the inlet / outlet mechanism gear 12 meshes with the rack 14; the rack 14 converts the rotation into a linear motion in the front and back directions through the cooperation with the inlet / outlet mechanism gear 12; the upper part of the rack fixed plate 11 is connected to the sample mechanism 4, and the sample mechanism 4 performs a linear motion in the front and back directions as the rack fixed plate 11 moves back and forth.

[0040] Figure 5In it, the sample mechanism 4 includes a heat dissipation unit 42 and a sample stage 41; the sample stage 41 is located on the heat dissipation unit 42; the heat dissipation unit 42 includes a heat dissipation bracket 421, heat dissipation support frames 422 are connected to both sides of the heat dissipation bracket 421, a radiator 423 is provided on the heat dissipation bracket 421, and the radiator 423 is supported by the heat dissipation support frames 422. A temperature control board 43 is also connected above the radiator 423.

[0041] Figure 6 In it, one side of the radiator 423 is connected to a cooling fan 424 through a heat dissipation channel, and three cooling fans 424 are provided in this figure. A display unit 5 is also provided above the box body, and the display content of the display unit 5 is controlled by a control unit.

[0042] Embodiment 3

[0043] Based on the above embodiments, the difference from Embodiment 2 is that Figure 3 In this embodiment, the driven gear set includes a first driven gear 222 and a second driven gear 223, and the lead screw 23 is connected to the first driven gear 222. The second driven gear 223 is located in the middle of the first driven gear 222; when the lifting motor 21 is started, it drives the driving gear 221 to drive the rotation of the lead screw 23 and the lifting operation of the lead screw nut. The driving gear 221 drives the first driven gear 222 that meshes with the driving gear 221, and coordinates the movement of the first driven gear 222 through the second driven gear 223.

[0044] Embodiment 4

[0045] Based on the above embodiments, Figure 11 In this embodiment, there are 2 lead screws 23. The driven gears include a first driven gear 222 and a second driven gear 223, and the lead screw is connected to the first driven gear 222. There are 2 second driven gears 223 in the middle of the first driven gear 222; when the lifting motor 21 is started, it drives the driving gear 221 to drive the rotation of the lead screw 23, and the lifting operation of the lead screw nut and the connected fixing plate 3. The driving gear 221 drives the first driven gear 222 close to the driving gear 221, and coordinates the movement of the first driven gear 222 through the second driven gear 223.

[0046] Embodiment 5

[0047] Based on the above embodiments, in this embodiment, there are two lead screws 23. The driven gears include a first driven gear 222, a second driven gear 223, and an intermediate driven gear 224. The lead screw is connected to the first driven gear 222. The second driven gear 223 is located beside the first driven gear 222, and the intermediate driven gear 224 is arranged in the middle. When the lifting motor 21 is started, it drives the driving gear 221 to drive the rotation of the lead screw 23. The rotation of the lead screw drives the lifting operation of the lead screw nut and the connected fixing plate 3. The driving gear 221 drives the first driven gear 222 close to it. The first driven gear 222 drives the second driven gear 223, and the intermediate driven gear 224 coordinates the movements of the first driven gear 222 and the second driven gear 223.

[0048] Embodiment 6

[0049] Based on the above embodiments, start the lifting motor 21, and the motor shaft starts to rotate to drive the driving gear 221. The model of the driving gear 221 is DS1-20 plastic gear 22. When it starts to rotate, it drives the first driven gear 222, the second driven gear 223, and the intermediate driven gear 224 to start rotating at the same time. The first driven gear 222 is a DS1-40 plastic gear 22 and is evenly distributed at the four corners. The second driven gear 223 is evenly arranged with 4 DS1-40 plastic gears 22 and 1 intermediate driven gear 224 DS1-80 plastic gear 22 to transmit motion, coordinating the plastic gears 22 at the four corners to rotate at a uniform speed simultaneously. The four lead screws 23 are fixed on the first driven gears 222 at the four corners and limit the up and down movement of the lead screws 23. Thus, the four lead screws 23 will rotate simultaneously following the plastic gears 22 of the first driven gear 222. Through the cooperation of the nut fixed in the guide rail fixing plate 3 assembly and the lead screw 23, the entire sample mechanism 4 moves up and down linearly at a uniform speed. Start the in-out motor 13, and the motor shaft of the in-out motor 13 starts to rotate to drive the in-out mechanism gear 12 to rotate self. The guide rail is fixed on the rack fixing plate 11, the slider 15 is fixed on the guide rail fixing plate 3, the gear 22 is fixed on the guide rail fixing plate 3, and through the cooperation of the rack 14 and the gear 22, the rack 14 will move linearly back and forth. The rack 14 and the sample mechanism 4 are both fixed on the rack fixing plate 11, so that the entire sample mechanism 4 moves linearly in the front-back direction.

[0050] The lifting motor 21 and the in-out motor 13 in this embodiment are both permanent magnet DC reduction motors. The motor drive chip selects Allegro A5950 to control the rotation speed and the forward or reverse direction. Of course, this is just an application example. Other drive chips or drive circuits can be selected to control the permanent magnet DC motor. If other types of motors are selected, there will be corresponding drive circuits.

[0051] Figure 7In the circuit, U8 is A5950. Its pins OUTA and OUTB are connected to the connection socket CN1 of the in-out motor 13. The LSS pin is connected in series with a sampling resistor R8 = 0.5 Ohm to the ground. The voltage generated on the LSS by the current flowing through R8 of the in-out motor 13 is amplified 5 times by the internal amplifier of A5950 and then output through the pin AIOUT. After low-pass filtering by R29 and C42, it is used as the motor current analog signal AIOUT1 and connected to the pin PA3 of the U5 single-chip microcomputer STM32F103, where it is converted into a digital signal through A / D conversion and then stored for software processing by the single-chip microcomputer MCU. U9 INA213 in the schematic diagram and the surrounding circuits R30, R, C43, and C44 are not installed and not used, so they are not described here.

[0052] According to the description in the A5950 data manual, the maximum current of the motor is limited to protect the motor. Specifically, the pin OCLSEL is connected to the 3.3V power supply through the resistor R24, that is, at a high level. The pin VREF is connected to the reference voltage of 2.55V divided by R26 and R27. At this time, the maximum current I(PEAK) for current limiting = VREF / (10*R8) = 0.51 amperes.

[0053] Figure 8 For the drive control of the lifting motor 21, the specific control principle can refer to the drive control of the in-out motor 13.

[0054] Figure 9 In the circuit, the control unit uses the I / O pins PB7 and PB5 of the U5 single-chip microcomputer STM32F103 of ST company to connect to the control logic input pins ENABLE and PHASE of A5950 to control the forward rotation, reverse rotation, or stop of the motor; U8 A5950 controls the in-out motor 13 according to the logic signal. Among them, the pin RESETn is connected to the 3.3V power supply through R25 and is always at a high level. The pin MODE is grounded and is always at a low level. Only the pins PHASE and ENABLE are used to control the in-out motor 13. When the U5 single-chip microcomputer pin PB7 outputs a low level to ENABLE, regardless of the level of PHASE, the motor will stop rotating. When ENABLE is at a high level, when the U5 single-chip microcomputer pin PB5 outputs a high level to PHASE, the motor rotates forward; when PHASE is at a low level, the motor rotates in reverse. Of course, this is only a connection method of the control pins in an A5950 control example.

Claims

1. A thermal cycler, comprising a box body, characterized in that, Inside the box, there is a lifting mechanism (2), a fixing plate (3) and a control unit; the control unit automatically controls the lifting of the lifting mechanism (2), the fixing plate (3) is connected to the lifting mechanism (2), and the fixing plate (3) moves up and down along with the lifting operation of the lifting mechanism (2).

2. The thermal cycler according to claim 1, characterized in that The fixing plate is provided with an inlet and outlet mechanism (1), and a sample mechanism (4) is connected to the inlet and outlet mechanism (1); the control unit automatically controls the inlet and outlet of the inlet and outlet mechanism (1); when the lifting mechanism (2) moves, the sample mechanism (4) will move up and down, and when the inlet and outlet mechanism (1) moves, the sample mechanism (4) moves in and out.

3. A thermal cycler according to claim 1, wherein, The lifting mechanism (2) includes a gear fixing plate (24), a lifting motor (21) and a lead screw (23); a gear (22) is provided on the fixed gear plate (24), the gear (22) includes a driving gear (221) and a driven gear set, and the lead screw (23) is connected to the driven gear set; When the lifting motor (21) starts, it drives the driving gear (221) to rotate, drives the driven wheel set (22) and the lead screw (23) to rotate, and causes the lead screw nut and the connected fixing plate (3) to move up and down along the lead screw.

4. A thermal cycler according to claim 3, wherein, The driven gear set includes a first driven gear (222) and a second driven gear (223), and the lead screw (23) is connected to the first driven gear (222), and the second driven gear (223) is located in the middle of the first driven gear (222); When the lifting motor (21) starts, it drives the driving gear (221) to drive the rotation of the lead screw (23) and the up and down movement of the lead screw nut. The driving gear (221) drives the first driven gear (222) that meshes with the driving gear (221), and coordinates the movement of the first driven gear (222) through the second driven gear (223).

5. A thermal cycler according to claim 3, characterized in that, The driven gear set includes a first driven gear (222), a second driven gear (223) and an intermediate driven gear (224). The first driven gear (222) is located at the four corners of the lifting mechanism (2), and the second driven gear (223) is evenly distributed in the middle of the lifting mechanism (2); the intermediate driven gear (224) is located in the middle of the second driven gear (223) of the lifting mechanism (2) for transmitting the movement of the second driven gear (223) and coordinating the movement of the first driven gear (222); the lead screw (23) is connected and passes through the first driven gear (222); when the lifting motor (21) starts, it drives the driving gear (221) to drive the rotation of the lead screw (23) and the up and down movement of the lead screw nut. The driving gear (221) drives the first driven gear (222) close to the driving gear (221), the first driven gear (222) drives the second driven gear (223), and coordinates the movement of the first driven gear (222) and the second driven gear (223) through the intermediate driven gear (224).

6. The thermal cycler according to claim 1, characterized in that, The feeding and discharging mechanism (1) includes a rack fixing plate (11), a feeding and discharging mechanism gear (12) and a feeding and discharging motor (13); the feeding and discharging mechanism gear (12) engages with a rack (14), and the feeding and discharging gear (22) is driven to rotate by the feeding and discharging motor (13), thereby driving the rack (14) to move; guide rails are provided on both sides of the rack fixing plate (11), and sliders (15) are connected to the guide rails, and the sliders (15) slide along the guide rails; the feeding and discharging motor (13) is fixedly connected to the fixing plate (3), and a rack (14) is provided at the bottom of the rack fixing plate (11); and the feeding and discharging mechanism gear (12) engages with the rack (14); the rack (14) converts the rotation into a linear motion in the front and back directions through the cooperation with the feeding and discharging mechanism gear (12); the upper part of the rack fixing plate (11) is connected to the sample mechanism (4), and the sample mechanism (4) performs a linear motion in the front and back directions as the rack fixing plate (11) moves back and forth.

7. A thermal cycler according to claim 1, characterized in that, The sample mechanism (4) includes a heat dissipation unit (42) and a sample stage (41); the heat dissipation unit (42) includes a heat dissipation bracket (421), a radiator (423) is provided on the heat dissipation bracket (421), and the sample stage (41) is located on the heat dissipation unit (42).

8. A thermal cycler according to claim 4, wherein The heat dissipation of the radiator (423) is cooled by air flow or liquid flow.

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