TWM587111U - Infrared material drying machine - Google Patents

Abstract

This creation describes an infrared dryer that includes a barrel and an infrared heater. The infrared heater includes a lamp load and a lamp power regulator. Among them, the lamp tube load can be driven to emit infrared rays for baking. The lamp tube power modulator is connected to the lamp tube load to drive the lamp tube load, and includes different switching devices, an inverter and a control unit. The control unit can turn on or off different switching devices, so that the lamp load can simply receive the signal output by the inverter or receive the signal from the mains and the inverter at the same time to emit infrared rays. Through the design of the above-mentioned infrared dryer, the specifications required for the inverter power components can be reduced, thereby reducing the overall cost of the dryer and uniformly heating the plastic particles.

Description

Infrared dryer

This creation relates to a dryer for drying plastic particles, particularly an infrared dryer, which can evenly heat plastic particles and has a small footprint.

The traditional roller hot air dryer uses a resistance heater and a fan to dry plastic particles. Compared with the infrared heat radiation drying technology, the traditional hot air drying technology, because the traditional hot air dryer uses dry hot air to heat the plastic particles, so it belongs to indirect heating. The drying takes longer and consumes more energy. Manufacturing costs are higher. In addition, due to the inclination of the barrel of the conventional drum, the thickness of the plastic particles inside the barrel is likely to be uneven or the material is turned unevenly, resulting in uneven heating. In addition, the traditional roller hot air dryer adopts continuous feeding and discharging. When the output needs to be increased, a longer-sized drying equipment is also required, resulting in an increase in the floor area. Compared with owners with limited plant space, It is not easy to use a conventional dryer. In addition, the traditional roller hot air dryer is continuous discharge, which must be continuously sucked by the suction machine, so it also consumes energy.

One of the purposes of this creation is to propose a new design of an infrared dryer, which has a lower cost but can also heat plastic particles uniformly.

The reason is that an infrared dryer provided according to the present invention includes a first cylinder and an infrared heater. The infrared heater is provided in the first barrel and includes a lamp load and a lamp power modulator. The lamp load can be driven to emit infrared rays. The lamp power modulator is connected to the lamp load to drive the lamp load. The lamp power modulator includes an inverter, a first switching device, a second switching device and a control unit. The inverter is coupled to the mains and can use the mains to output an AC drive signal. The first switching device is coupled to the inverter and the lamp tube load, the second switching device is coupled to the lamp tube load and the mains power, and the control unit is coupled to the first switching device and the second switching device to control the first switching device and the first switching device. The two switching devices are turned on or off, and the control unit also controls the AC drive signal that the inverter output is synchronized with the mains.

Therefore, when an infrared dryer is used to dry wet plastic particles, the plastic particles can be directly heated by the infrared light emitted from the load of the tube, so the plastic particles can be heated more uniformly and can be improved. The heating efficiency of plastic particles can save overall energy consumption and overall heating time. In addition, the first and second switching devices are controlled by the control unit. When the heating temperature of the infrared dryer reaches the baking temperature, the infrared dryer no longer needs full power output, and the first switch can be turned off by the control unit. The device simply heats the plastic particles by outputting AC drive signals from the inverter, which can reduce the specifications required for the power components of the inverter, and can buy a suitable lamp power regulator at a lower price. Converter, thereby reducing the overall cost of the infrared dryer.

In one aspect, the lamp power modulator also includes a feedback detection circuit, and detects the phase of the AC drive signal through the feedback detection circuit and inputs the phase of the detected AC drive signal to the control. Unit to facilitate subsequent operation of AC drive signals synchronized with the mains.

In another aspect, the lamp power modulator further includes a temperature feedback circuit. The temperature feedback circuit is to detect an output power of the lamp load, and input the detected output power to the control unit, so that the control unit can respond to the different heating processes of the plastic particles (such as the heating section and the holding section). The inverter controls the inverter and the first and second switching devices so that the lamp load can output infrared rays with suitable output power.

In another aspect, the lamp power modulator has a rated maximum output power. When the control unit detects that the output power of the lamp load is greater than or equal to the rated maximum output power through the temperature feedback circuit, the control unit is turned on for the first time. For the switching device and the second switching device, the control unit adjusts the inverter output and the AC drive signal of the inverting mains power to control the power by this method. When the control unit performs closed-loop temperature and power control through the temperature feedback circuit, When the control unit detects that the output power of the lamp load is less than the rated maximum output power, the control unit turns on the first switching device and disconnects the second switching device, and the control unit adjusts the inverter output and the mains power in phase or reverse phase AC drive Signal. The above control mechanism can effectively reduce the component specifications required for the inverter power components.

In another aspect, the temperature feedback circuit further includes a temperature detector that detects the temperature of the plastic particles disposed in the first barrel, and the temperature feedback circuit is based on the detected plastic particles. The output power of the lamp load is obtained corresponding to the temperature.

In another aspect, the infrared dryer further includes a support frame and a first lifting mechanism, wherein the first barrel is horizontally disposed on the support frame, and the first lifting mechanism is disposed on the support frame and connected to the barrel. A lifting mechanism can be driven to lift the first cartridge so that the first cartridge is in an inclined state. Through the first lifting mechanism, when the plastic particles are dried, the first lifting mechanism can be directly driven to facilitate the subsequent extraction of the dried plastic particles, and because the first lifting mechanism can quickly pour out the plastic particles, the drying can be reduced. After the contact time between the plastic particles and the external environment, the moisture content of the plastic particles is not easily affected by the external environment temperature and humidity. In addition, because the load of the tube has been able to uniformly heat the plastic particles, the length of the first barrel does not need to be designed to be very long, so the footprint of the infrared dryer can be effectively reduced, and it can be applied to Smaller scale plant.

In another aspect, in order to allow the infrared dryer to dry plastic particles in batches and to achieve a modular design to meet the customer's baking needs. The infrared dryer can further include a second material cylinder and a second lifting mechanism (or a third material cylinder and a third lifting device ...). The second material cylinder is horizontally arranged on the support frame and located on the first Above the barrel, a second lifting mechanism is provided on the support frame and is connected to the second barrel. The second lifting mechanism can be driven to lift the barrel so that the barrel is inclined. In addition, due to different types of plastic particles, some plastic particles need to be crystallized, so the second cylinder can also be used for crystallization, so that the infrared dryer can have both functions of crystallization and baking.

In another aspect, the first lifting mechanism (or the second lifting mechanism) includes a pneumatic cylinder, a first link and a second link, wherein one end of the first link is connected to the first cylinder, and the second link One end of the rod is connected to the support frame, one end of the first link opposite the end and one end of the second link relative to the support are connected to a telescopic rod of the pneumatic cylinder, and the pneumatic cylinder is provided on the support.

In another aspect, after the infrared drying machine finishes drying, it can be quickly discharged by the discharge mechanism device to reduce the combination of the plastic material and the moisture in the environment, and the plastic material maintains a dry moisture content.

In another aspect, the infrared dryer can also be used with a particle size screening device, and the particle size screening device is arranged on the second barrel and connected to the second barrel. In this way, the area of the plant can be reduced better.

The following describes the technical content and features of this creation in detail through the listed embodiments and drawings. The "up", "down", "inside", "outside", "top", Directional adjectives such as "bottom" are only examples of description terms based on the direction of normal use, and are not intended to limit the scope of claims.

In order to explain the technical characteristics of this creation in detail, the following two embodiments are given below and illustrated with drawings, as follows:

Please refer to FIG. 1 and FIG. 3, a first embodiment provides an infrared dryer 1, which includes a first barrel 20, a support frame 30, and an infrared heater 10. The first barrel 20 is horizontally arranged (that is, the axial direction of the first barrel 20 is parallel to the ground) and is rotatably disposed on the support frame 30. The support frame 30 is provided with four sets of rollers 41 (in FIG. 1, two sets of rollers 41 are covered) and a set of motors 40. The rollers 41 are divided into two groups and are respectively disposed on two sides of the first barrel 20, and The four sets of rollers 41 are rotatably mounted on the support frame 30. The group of motors 40 (including a reduction gear box) is connected to one of the rollers 41 and can drive the rollers 41 to rotate, thereby driving the first cylinder 20 to rotate. As shown in FIG. 3, the inner wall of the first barrel 20 is provided with a plurality of paddles 21 at an equal angle. Through the rotation of the paddles 21 and the first barrel 20, the paddles 20 can be evenly flipped. Plastic particles inside (not shown). In addition, the support frame 30 is also provided with two sets of dehumidifiers 50, which are connected to the first barrel 20 through a pipeline (not shown), so that the humid plastic particles can pass through the dehumidifier after generating moisture due to heating. 50 while excluding water vapor.

As shown in FIGS. 2 and 4, the support frame 30 includes a first frame body 31 and a second frame body 32. The first frame body 31 is erected on the ground, and the second frame body 32 is erected on the first frame. A frame 31 and the motor 40 and the first barrel 20 are both mounted on the second frame 32. The features of this part will be described in more detail in the subsequent paragraphs.

As shown in FIG. 3, the infrared heater 10 is provided inside the first barrel 20, and includes a lamp holder 11 and a lamp cover 12, a lamp load 13 and a lamp power provided on the lamp holder 11. Modulator 60 (see Figure 6). The lamp tube load 13 can be driven to emit infrared rays, and the emitted infrared rays can directly irradiate plastic particles under the guidance of the lamp cover 12. The angle of the lamp tube holder 11 can be adjusted to change the infrared irradiation range.

Please refer to FIG. 5 to FIG. 7, the lamp tube power modulator 60 is connected to the lamp tube load 13 to drive the lamp tube load 13 to emit infrared rays. The lamp tube power modulator 60 includes an inverter 61, a first switching device 62, a second switching device 63, and a control unit 64. The inverter 61 is a full-bridge inverter 61 in this embodiment. The full-bridge inverter 61 has a plurality of transistors T1-T4 (such as MOSFETs or IGBTs). As shown in FIG. 7, after the mains AC passes a rectifier 65 and a booster circuit 66 and passes power factor correction and filtering, an AC signal of the mains AC will be converted into a direct current signal. The DC signal is converted into an AC drive signal at a high frequency.

The first switching device 62 is coupled to the inverter 61 and the tube load 13. The first switching device 62 can be turned on or off under the control of the control unit 64, so as to control the inverter 61 to output or not output an AC driving signal to the lamp. Tube load 13 (output to the tube load 13 through the isolation transformer F).

The second switching device 63 is coupled to the mains AC and the tube load 13. The second switching device 63 may also be turned on or off under the control of the control unit 64 to control whether the mains AC is output or not to the tube load 13 (through Isolation transformer F and output to lamp load 13)

The control unit 64 in this embodiment is a dsPIC digital signal processing chip. As shown in FIG. 7, the control unit 64 detects the phase of the AC driving signal through a feedback detection circuit 67 and applies the detected AC driving signal. The phase of the signal is input to the control unit 64. An analog-to-digital converter 641 is built in the control unit 64, and a PLL phase-locked counter 642 is written in a programmatic manner for phase locking, and a system sinusoidal control signal amplitude modulation mechanism 643 enables the control unit 64 to follow A series of front-end drive and isolation circuit 68 is used to output a modulated PWM signal, so that the inverter 61 can output an AC drive signal synchronized with the mains AC according to the modulated PWM signal, so that the frequency of the AC drive signal can be equal. The mains AC (60 Hz) and the phase of the AC drive signal are the same as the mains AC. The aforementioned front-end driving and isolating circuit 68 includes a digital analog converter 68a, an internal loop wave control circuit 68b, a power transistor driving circuit 68c, and an optical coupling isolating circuit 68d, which are sequentially coupled. The digital analog converter 68a is used for digital / analog conversion of the signal. The internal loop wave control circuit 68b is used to output the PWM signal correspondingly. The power transistor drive circuit 68c receives the above PWM signal and can modulate the PWM signal for subsequent driving. The transistors T1-T4 of the inverter 61 and the optical coupling isolation circuit 68d serve as isolation protection and input a modulated PWM signal to the inverter 61 to drive the transistors T1-T4.

On the other hand, as shown in FIG. 5, the tube power modulator 60 further includes a temperature feedback circuit 69. The temperature feedback circuit 69 includes a temperature sensor (such as a thermocouple, not shown). The control unit 64 detects the temperature of the plastic particles (or the first barrel 20) through a temperature sensor, and the detected temperature corresponds to an output power of the lamp tube load 13, and the control unit 64 then determines The output power regulates the baking process of the plastic particles.

Regarding the operation of the infrared dryer 1 of this embodiment, please refer to FIG. 5, FIG. 8 and FIG. 9, and the following tables.
time First switching device 第二 开关 装置 The second switching device AC drive signal status 0-t1 disconnect Continuity 0 Heating section t1-t2 Continuity Continuity Reverse Adjusting output power t2-t3 Continuity disconnect Normal phase t3 ~ Continuity disconnect Normal phase Holding temperature section

First, when a user starts to transfer wet plastic particles into the first cylinder 20, the control unit 64 turns on the motor 40 to rotate the first cylinder 20, and the control unit 64 also turns off the first switching device 62 and turns on the first Two switching devices 63 enable the lamp load 13 to use commercial AC only to output 100% of the rated maximum output power of the infrared (corresponding to the voltage of 220 volts, as shown in the upper graph of FIG. 9), and maintain the 100% output power for a period of time ( That is, the time from 0 to t1 in FIG. 8). This period of time is the heating period during the baking process of the plastic particles, so that the temperature in the first barrel 20 rises to a baking temperature. The baking temperature is based on the plastic particles. Set the actual material.

When the baking temperature or specific power is reached, the control unit 64 starts to reduce the output power of the lamp load 13. At this time, the control unit 64 controls the inverter 61 to output an AC drive signal that is inverse to the mains AC (as shown in Figure 9). Figure), and can gradually increase the voltage amplitude of the AC drive signal, so that the voltage amplitude of the composite signal (the signal after the mains and AC drive signals are added) that is finally delivered to the lamp load 13 decreases until the lamp load The output power of 13 is equal to the rated maximum output power of the infrared heater 10 (at this point in time t2, the voltage amplitude of the AC drive signal is -110 volts).

Next, the control unit 64 turns off the second switching device 63 (the first switching device 62 is on at this time), and controls the inverter 61 to output an AC driving signal in phase with the mains AC (at this time the mains AC is no longer passed through the second The switching device 63 is input to the lamp load 13), and the lamp load 13 will simply use an AC drive signal. From time point t2 to t3, the control unit 64 gradually decreases the voltage amplitude of the AC drive signal until the plastic particles begin to reach thermal equilibrium.

It should be noted that, because the second switching device 63 is off and the first switching device 62 is on, in this case, only the AC driving signal is input to the lamp load 13, in this case, the control Even if the unit 64 controls the AC drive signal to invert the AC drive signal and the mains AC, in this case, the lamp load 13 can also use the AC drive signal output by the inverter 61 to emit infrared light.

Finally, after the time point t3, the lamp load 13 maintains a low output power (for example, the corresponding voltage amplitude is 44 volts). At this time, the AC driving signal is still in phase, and the second switching device 63 is still open. Until the moisture content of the plastic particles reaches the requirements, the infrared heater 10 is turned off, and the dried plastic particles can be used for plastic molding.

Therefore, it can be seen that through the above control method, the inverter 61 only needs to output an AC driving signal with a maximum voltage amplitude of 110 volts, and the output power of the lamp load 13 can be regulated and output exceeds the rating of the infrared heater 10 The maximum output power can reduce the requirements of various power element specifications of the infrared heater 10, so that the overall cost of the infrared dryer 1 can be reduced, and the plastic particles can be uniformly heated.

Finally, in order to facilitate the extraction of the dried plastic particles, a first lifting mechanism 70 is also designed in this embodiment, please refer to FIG. 2 and FIG. 4. The first lifting mechanism 70 includes a pneumatic cylinder 71, a first link 73 and a second link 74. One end of the pneumatic cylinder 71 is pivotally connected to the first frame 31. The pneumatic cylinder 71 is electrically connected to the control unit 64 and has A telescopic rod 72 enables the control unit 64 to control the pneumatic cylinder 71 to extend or shorten the telescopic rod 72. One end of the first link 73 is pivotally connected to the telescopic rod 72, and the other end of the first link 73 is pivotally connected to the bottom of the second frame body 32 (that is, the first lifting mechanism 70 is passed through the second frame body 32 While connecting the first cylinder 20), one end of the second link 74 is pivotally connected to the first link 73 and the telescopic rod 72, and the other end of the second link 74 is pivotally connected to the first frame 31. In this way, when the control unit 64 drives the first lifting mechanism 70, the second frame body 32 and the first barrel 20 can be lifted so that the first barrel 20 is inclined (see FIG. 4), so as to facilitate subsequent extraction and drying. Dried plastic particles. In addition, the infrared dryer 1 is also designed with a discharging mechanism 80 for opening the outer cover 22 of the first barrel 20 so that the plastic particles can be quickly discharged from the first barrel 20 to a storage barrel.

The present invention further provides a second embodiment, please refer to FIG. 10. The dryer 1 'of the second embodiment includes a particle size screening device 91, a first dryer unit 92, and a second dryer unit 93. The second baking unit 93 is located above the first baking unit 92, and the particle size screening device 91 is located above the second baking unit 93. The first baking unit 92 includes components such as the first barrel 20, a support frame 30, an infrared heater 10, and a first lifting mechanism 70 as described in the first embodiment for baking processing. The second drying unit 93 has components such as a second cylinder (not shown), an infrared heater 10 and a second lifting mechanism (not shown), and uses a support frame 30 of the first drying unit 92. The structure of the second cylinder is the same as that of the first cylinder 20, the structure of the second lifting mechanism is the same as that of the first lifting mechanism 70, and one end of the first link of the second lifting mechanism is connected to the second cylinder (or Is connected to the second cylinder through a third frame body), one end of the second link is connected to the support frame, one end of the first link to the second cylinder and one end of the second link to the support frame are connected One of the pneumatic cylinders is a telescopic rod, and the pneumatic cylinder is arranged on a support frame. The support frame 30 of the second baking unit 93 is the same as the infrared heater 10. The second baking unit 93 is used to crystallize the plastic particles. The first drying unit 92 and the second drying unit 93 are arranged between the second drying unit 93 and the particle size screening device 91 to transfer plastic particles. The particle size screening device 91 includes a particle size screening machine (not shown in the figure) and a feeding port 911. The particle size screening machine is used for screening plastic particles, and the bad plastic particles are discharged to the crusher G for crushing. After the first baking unit 92 finishes baking the plastic particles, it can be transported to the injection molding machine M through a pipeline for plastic molding operation.

Through the structural design of the infrared dryer 1 'of the second embodiment, an infrared dryer 1' can have three functions of particle size screening, crystallization and drying of plastic particles, and the first drying unit 92, The second drying unit 93 and the particle size screening device 91 are vertically arranged, which can effectively reduce the area of the plant, so it can make the most effective use of the plant area, and can be applied to smaller plants, or For customized baking operations. Of course, if the output is required, a third drying unit (not shown) may be provided between the second drying unit 93 and the first drying unit 92.

The examples listed above are used to clarify the feasible implementation patterns of this creative embodiment. This creation is not limited to the above-exemplified implementation patterns. Anyone who makes some modifications to it within the scope of the ideas revealed in this creation And change should still fall within the scope of this creation.

1,1'‧‧‧drying machine
10‧‧‧ Infrared heater
11‧‧‧lamp bracket
12‧‧‧ Lampshade
13‧‧‧ Lamp Load
20‧‧‧ the first barrel
21‧‧‧Pick
22‧‧‧ Cover
30‧‧‧ support
31‧‧‧First frame
32‧‧‧Second frame
40‧‧‧Motor
41‧‧‧roller
50‧‧‧ dehumidifier
60‧‧‧lamp power regulator
61‧‧‧Inverter
62‧‧‧The first switching device
63‧‧‧Second switch device
64‧‧‧control unit
641‧‧‧ Analog Digital Converter
642‧‧‧PLL Phase Lock Counter
643‧‧‧System Sine Control Signal Amplitude Modulation Mechanism
65‧‧‧ Rectifier
66‧‧‧Boost circuit
67‧‧‧Feedback detection circuit
68‧‧‧Front end drive and isolation circuit
68a‧‧‧ Digital Analog Converter
68b‧‧‧Inner loop wave control circuit
68c‧‧‧Power transistor driving circuit
68d‧‧‧Optical coupling isolation circuit
69‧‧‧Temperature feedback circuit
70‧‧‧The first lifting mechanism
71‧‧‧Pneumatic cylinder
72‧‧‧ Telescopic Rod
73‧‧‧First connecting rod
74‧‧‧Second Link
80‧‧‧Discharge organization
91‧‧‧ particle size screening device
911‧‧‧Inlet
92‧‧‧The first drying unit
93‧‧‧second drying unit
T1-T4‧‧‧Transistors
F‧‧‧Transformer
AC‧‧‧City Power
G‧‧‧Crusher
M‧‧‧ injection molding machine

The detailed structure, characteristics, assembly or use of the infrared dryer will be described in the following embodiments. However, it should be understood that the embodiments and drawings described below are only for illustrative purposes, and they are not Should be used to limit the scope of patent applications for this creation, where:

1 is a perspective view of an infrared dryer in the first embodiment;
Figure 2 is a side view of Figure 1;
3 is a sectional view taken along line 3-3 of FIG. 2;
4 is a schematic diagram of the operation of the infrared dryer of the first embodiment, used to explain the situation after the first cylinder is lifted;
5 to 7 are circuit block diagrams of a lamp tube power modulator, a lamp tube load and a mains power in the first embodiment;
8 is a relationship diagram between a load power percentage and a heating time in the embodiment;
FIG. 9 is a schematic diagram of the synthesis of the mains and AC drive signals; and FIG. 10 is a schematic diagram of the structure of the infrared dryer of the second embodiment.

Claims (10)

An infrared dryer includes: a first barrel; an infrared heater provided in the first barrel and including a lamp load and a lamp power modulator, the lamp load can be driven When the infrared light is emitted, the lamp power modulator is connected to the lamp load to drive the lamp load. The lamp power modulator includes: an inverter, which is coupled to the mains power and can use the mains power to output an AC drive. A signal; a first switching device coupled to the inverter and the lamp load; a second switching device coupled to the lamp load and mains power; a control unit coupled to the first switching device and the second The switching device controls the first switching device to be turned on or off with the second switching device, and the control unit also controls the AC drive signal synchronized with the inverter output and the mains power. The infrared dryer according to claim 1, wherein the lamp power modulator further includes a feedback detection circuit, the feedback detection circuit detects the phase of the AC drive signal and detects the detected The phase of the AC drive signal is input to the control unit. The infrared dryer according to claim 1, wherein the lamp power modulator further includes a temperature feedback circuit, and a temperature detection result of the temperature feedback circuit corresponds to an output power of the lamp load, and The detected output power is input to the control unit. The infrared dryer as described in claim 3, wherein the lamp power modulator has a rated maximum output power. When the control unit performs closed-loop temperature and power control through the temperature feedback circuit, when the control unit detects When it is detected that the output power of the lamp tube load is greater than or equal to the rated maximum output power, the control unit turns on the first switching device and the second switching device, and the control unit adjusts the inverter output and the mains inversion The AC drive signal; when the control unit detects that the output power of the lamp load is less than the rated maximum output power through the temperature feedback circuit, the control unit turns on the first switching device and turns off the second Switch, the control unit adjusts the AC drive signal in which the inverter output and the mains are in phase or in phase. According to the infrared dryer of claim 3, the temperature feedback circuit further includes a temperature detector that detects the temperature of the plastic particles set in the first barrel, and the temperature returns The power supply circuit obtains the output power according to the detected temperature of the plastic particles. The infrared dryer according to claim 1, further comprising a support frame and a first lifting mechanism. The first cylinder is horizontally and rotatably provided on the support frame. The first lifting mechanism is The first lifting mechanism is arranged on the support frame and connected to the cartridge, and the first lifting mechanism can be driven to raise the cartridge so that the first cartridge is in an inclined state. The infrared dryer according to claim 6, further comprising a second cylinder and a second lifting mechanism, the second cylinder is horizontally disposed on the support frame and located above the first cylinder, The second lifting mechanism is provided on the support frame and is connected to the second cylinder. The second lifting mechanism can be driven to raise the second cylinder so that the cylinder is in an inclined state. The infrared dryer according to claim 6, wherein the support frame includes a first frame body and a second frame body, the second frame body is liftably disposed on the first frame body, and the first A barrel is provided on the second frame. The first lifting mechanism includes a pneumatic cylinder, a first link and a second link. One end of the first link is connected to the second frame. One end of two connecting rods is connected to the first frame body. One end of the first connecting rod with respect to the ground frame body and one end of the second connecting rod with respect to the second frame body are connected to a telescopic rod of the pneumatic cylinder. The pneumatic cylinder is arranged on the first frame. The infrared dryer according to claim 7, wherein the support frame includes a first frame body and a third frame body, and the second lifting mechanism includes a pneumatic cylinder, a first link, and a second link , One end of the first link is connected to the second cylinder, one end of the second link is connected to the support frame, one end of the first link is opposite to the second cylinder and the second link is opposite to the One end of the first frame body is connected to a telescopic rod of the pneumatic cylinder, and the pneumatic cylinder is disposed on the first frame body. The infrared dryer according to claim 7 , further comprising a particle size screening device, the particle size screening device is disposed on the second cylinder and is connected to the second cylinder.