CN113098203B - Cooling circulation system and method for reducing thermal error of machine tool spindle - Google Patents

Cooling circulation system and method for reducing thermal error of machine tool spindle Download PDF

Info

Publication number
CN113098203B
CN113098203B CN202110443186.8A CN202110443186A CN113098203B CN 113098203 B CN113098203 B CN 113098203B CN 202110443186 A CN202110443186 A CN 202110443186A CN 113098203 B CN113098203 B CN 113098203B
Authority
CN
China
Prior art keywords
cooling
bearing
heat
motor
spindle
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202110443186.8A
Other languages
Chinese (zh)
Other versions
CN113098203A (en
Inventor
陈国华
左乾君
杨晓平
张海燕
李毅
闫青
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hubei Gucheng County Donghua Machinery Co ltd
Original Assignee
Hubei University of Arts and Science
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hubei University of Arts and Science filed Critical Hubei University of Arts and Science
Priority to CN202110443186.8A priority Critical patent/CN113098203B/en
Publication of CN113098203A publication Critical patent/CN113098203A/en
Application granted granted Critical
Publication of CN113098203B publication Critical patent/CN113098203B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K9/00—Arrangements for cooling or ventilating
    • H02K9/19—Arrangements for cooling or ventilating for machines with closed casing and closed-circuit cooling using a liquid cooling medium, e.g. oil
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
    • H02K11/20—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection for measuring, monitoring, testing, protecting or switching
    • H02K11/21—Devices for sensing speed or position, or actuated thereby
    • H02K11/215—Magnetic effect devices, e.g. Hall-effect or magneto-resistive elements
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
    • H02K11/20—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection for measuring, monitoring, testing, protecting or switching
    • H02K11/25—Devices for sensing temperature, or actuated thereby
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K11/00—Structural association of dynamo-electric machines with electric components or with devices for shielding, monitoring or protection
    • H02K11/30—Structural association with control circuits or drive circuits
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K5/00—Casings; Enclosures; Supports
    • H02K5/04—Casings or enclosures characterised by the shape, form or construction thereof
    • H02K5/16—Means for supporting bearings, e.g. insulating supports or means for fitting bearings in the bearing-shields
    • H02K5/173—Means for supporting bearings, e.g. insulating supports or means for fitting bearings in the bearing-shields using bearings with rolling contact, e.g. ball bearings
    • H02K5/1732—Means for supporting bearings, e.g. insulating supports or means for fitting bearings in the bearing-shields using bearings with rolling contact, e.g. ball bearings radially supporting the rotary shaft at both ends of the rotor
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K5/00—Casings; Enclosures; Supports
    • H02K5/04—Casings or enclosures characterised by the shape, form or construction thereof
    • H02K5/20—Casings or enclosures characterised by the shape, form or construction thereof with channels or ducts for flow of cooling medium
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K9/00—Arrangements for cooling or ventilating
    • H02K9/02—Arrangements for cooling or ventilating by ambient air flowing through the machine
    • H02K9/04—Arrangements for cooling or ventilating by ambient air flowing through the machine having means for generating a flow of cooling medium
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P29/00—Arrangements for regulating or controlling electric motors, appropriate for both AC and DC motors
    • H02P29/60—Controlling or determining the temperature of the motor or of the drive
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K2213/00—Specific aspects, not otherwise provided for and not covered by codes H02K2201/00 - H02K2211/00
    • H02K2213/03—Machines characterised by numerical values, ranges, mathematical expressions or similar information
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/10—Greenhouse gas [GHG] capture, material saving, heat recovery or other energy efficient measures, e.g. motor control, characterised by manufacturing processes, e.g. for rolling metal or metal working

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Auxiliary Devices For Machine Tools (AREA)

Abstract

The invention relates to the field of machine tool spindle cooling, in particular to a cooling circulation system and a method for reducing thermal errors of a machine tool spindle. The invention can improve the cooling efficiency, realize the effective control of the temperature and the thermal deformation of the machine tool spindle, overcome the defects of non-adjustable cooling, unbalanced cooling and low cooling efficiency of the traditional cooling method, and has better engineering application prospect.

Description

Cooling circulation system and method for reducing thermal error of machine tool spindle
Technical Field
The invention relates to the field of machine tool spindle cooling, in particular to a cooling circulation system for reducing thermal errors of a machine tool spindle.
Background
With the rapid development of the manufacturing equipment technology in China, the precision requirement of the machine tool is higher and higher. The high-power main shaft system of the precision machine tool ensures the high efficiency and quality of machine tool processing. However, during the operation of the machine tool spindle at high speed and for a long time, the spindle bearing and the motor generate a large amount of heat. The heat is transferred to other parts of the spindle and the spindle box through heat radiation, heat conduction and the like, so that various parts of the spindle and the spindle box are heated unevenly, thermal errors are generated in the axial direction and the radial direction of the spindle, and the machining precision of a machine tool is influenced finally.
Aiming at the problem of thermal error caused by the heat generation of a machine tool spindle, a method for improving heat dissipation capacity by arranging a cooling device is adopted at present. Chinese patent specification CN 101524855B discloses a spindle cooling structure for cooling a spindle by using an air cooling device, in which a cooling fan is installed at the rear end of a spindle housing, an axial air duct is formed between the housing, a bearing block and an air cylinder, and the spindle is cooled by using air circulation flow. This approach does not provide good cooling for the high speed motorized spindle. In chinese patent No. CN 111347288B, a cooling and lubricating structure for an electric spindle is disclosed, in which a cooling medium channel is arranged in a spindle box, and a spindle is cooled by injecting a cooling liquid. However, the flow channel arrangement of the cooling medium inlet is only one, and the circulation period of the cooling medium in the branch is too long, so that the bearing and the motor cannot be sufficiently cooled.
Disclosure of Invention
The invention aims to solve the technical problem of overcoming the defect of insufficient cooling effect of a cooling device in the prior art, and provides a cooling system for reducing the thermal error of a machine tool spindle, which can improve the heat dissipation effect, realize the effective control of the temperature and deformation of the machine tool spindle and improve the machining precision of the machine tool.
In order to achieve the purpose, the invention provides the following technical scheme:
the utility model provides a reduce cooling circulation system of lathe main shaft thermal error, its characterized in that, includes the main shaft box, sets up the main shaft in the main shaft box, and the motor sets up in the main shaft middle section the motor overcoat has the motor cooling jacket, has arranged two sets of opposite direction's motor cooling runner on the motor cooling jacket, and a plurality of temperature sensor distribute on the motor, and the front end and the rear end of main shaft are provided with antifriction bearing respectively, the bearing overcoat has the bearing cooling jacket, and the main shaft is equipped with speed sensor, and cooling module is connected with the cooling runner, and data processing controller is connected with temperature sensor, speed sensor and cooling module.
In the cooling circulation system for reducing the thermal error of the spindle of the machine tool, the cooling component comprises an air cooling machine, a cooling oil tank, a cooling water pump and an electronic type circulating cooling water regulating valve which are sequentially connected; the cooling flow channel comprises a flow channel, a first cold inlet pipe orifice, a second cold inlet pipe orifice, a first hot outlet pipe orifice and a second hot outlet pipe orifice; the first cold inlet pipe orifice is arranged above the cooling jacket, the first hot outlet pipe orifice is arranged below the cooling jacket, the second cold inlet pipe orifice is arranged above the bearing cooling jacket, the second hot outlet pipe orifice is arranged below the bearing cooling jacket, and the first cold inlet pipe orifice and the second cold inlet pipe orifice are respectively provided with an electronic type circulating cooling water regulating valve.
In foretell cooling circulation system who reduces lathe main shaft thermal error, electronic type recirculated cooling water governing valve links to each other with the input sprue, the input sprue links to each other with cooling water pump, the cooling oil tank oil-out is connected to the cooling water pump other end, and infrared temperature sensor monitors cooling oil tank oil-out coolant liquid temperature, the first, two hot outlet pipe mouths of cooling jacket link to each other with the output sprue, the output sprue is connected with air-cooled machine oil inlet, the air-cooled machine oil-out is connected with the cooling oil tank oil inlet be equipped with hall formula tachometric sensor on the main shaft 1.
A control method of a cooling circulation system for reducing the thermal error of a main shaft of a machine tool is characterized by comprising
Step 1, analyzing the heat source of the main shaft part comprises the following steps: the friction heat of the main shaft bearing and the heat of the main shaft motor;
step 2, carrying out spindle heating and heat transfer analysis:
step 2.1, the calorific value of the bearing 2 is calculated by the following formula:
Q＝1.047×10 -4 nM (1)
wherein n is the bearing rotation speed (rpm); m is the total friction moment (N.mm) of the bearing; q is a calorific value (W);
the total friction torque of the bearing 2 comprises three parts:
M＝M 1 +M 2 +M 3 (2)
(1) Friction moment M generated by external load 1 ：
M 1 ＝f 1 F β d m (3)
Wherein f is 1 Is a coefficient determined by the bearing structure and the load, F β Is the equivalent external load, dm is the bearing mean diameter;
(2) Friction moment M generated by spin motion of roller path contact area 2 ：
Figure BDA0003035911190000031
Wherein mu is the sliding friction coefficient, sigma is the contact stress found at the raceway, a is the contact ellipse major semiaxis, and E is the second type complete ellipse integral;
(3) Viscous friction torque M of lubricating fluid 3 ：
Figure BDA0003035911190000032
Wherein v is 0 Is the dynamic viscosity of the lubricant, f 0 Is a coefficient determined by the type of bearing and the manner of lubrication;
finishing to obtain:
Figure BDA0003035911190000041
step 2.2, the heat productivity of the motor is converted from the loss power of the motor, and the method comprises three parts:
(1) Power loss of the stator 8:
P d ＝P Cu1 +P Fe (7)
wherein P is Cu For copper consumption, P Fe In order to reduce the iron loss, the iron-based alloy is used,
Figure BDA0003035911190000042
Figure BDA0003035911190000043
wherein I 1 For stator winding line current, r 1 Is the winding resistance, I em 、r em The excitation current and the excitation resistor;
(2) The power consumption losses of the rotor 6 are similar to the copper losses:
Figure BDA0003035911190000044
wherein I 2 Is rotor current, r 2 Is rotor resistance, s is motor slip, P em Is the electromagnetic power;
P em ＝P 1 -P d (11)
wherein P is 1 Inputting power for the electric spindle:
Figure BDA0003035911190000045
wherein U is 1 In order to provide the stator winding line voltage,
Figure BDA0003035911190000046
is the power factor;
(3) Stator 8 rotor 6 air gap friction losses:
P m ＝πkCρω 3 R 4 L (13)
wherein k is a rotor surface roughness coefficient, C is an air friction coefficient, rho is an air density, and omega, R and L are a rotor angular velocity, a rotor radius and a rotor axial length respectively;
finishing to obtain:
Figure BDA0003035911190000051
step 2.3, spindle Heat transfer analysis
Q＝CMΔT (15)
Wherein Q is the heat generated, C is the specific heat capacity of the material, M is the mass of the object, Δ T is the temperature rise, Δ T = T 1 -T 2 ，T 1 Is the temperature of the electric spindle, T 2 For ambient temperature, T can be solved from equation (15) 1 ；
The heat dissipation of the main shaft part mainly exchanges heat with the external environment through the shell, and the heat transfer quantity of the radial heat conduction of the main shaft is as follows:
Figure BDA0003035911190000052
wherein Q cr Is the amount of heat transfer between two points, T 1 Is the temperature of the electric spindle, T 3 Is the temperature of the electric spindle housing, B is the annular width, r i 、r o The inner radius and the outer radius of the electric spindle shell are respectively;
step 2.4, thermal convection analysis
The forced convection heat exchange quantity generated by the cooling liquid and the surface of the shell under the external action is as follows:
Q v ＝h v S(T 5 -T 4 ) (17)
wherein Q v Is the heat flow between any two points of the cooling liquid and the shell in the process of heat convection, T 5 、T 4 The temperature of the shell surface and the cooling liquid respectively, S is the heat transfer area vertical to the heat flow direction between two points, h v Is the convective heat transfer coefficient;
Figure BDA0003035911190000053
wherein N is u Is a dimensionless parameter, λ w As thermal conductivity of the cooling fluid, d c Is a characteristic length, R e Is Reynolds number, P r Is a Plantt number, rho is a fluid density, v is a fluid flow velocity, eta is a fluid flow viscosity coefficient, d is a pipeline diameter, cp is an isobaric specific heat capacity, k is a thermal conductivity, and mu is a dynamic viscosity;
finishing to obtain:
Figure BDA0003035911190000061
under an ideal condition, let Q v1 ＝Q M Then the bearing coolant flow velocity v can be solved by equation (18) 1 (ii) a Let Q v2 ＝Q j Then the motor coolant flow rate v can be solved by equation (18) 2 The effect of respectively controlling the cooling capacities of the bearing and the motor is achieved;
and 3, monitoring the rotation speed n of the main shaft by the Hall rotation speed sensor, if the rotation speed n is 0, enabling the cooling system to not work, if the rotation speed n is not 0, enabling the next step of work to be carried out, acquiring the real-time working temperature T1 of the cooling liquid by the infrared temperature sensor, calculating the cooling liquid flow rate v required by cooling by calculating the heat productivity of each bearing and the motor, adjusting the opening and closing degree of the cooling water regulating valve and different output powers of the cooling water pump according to the calculated cooling liquid flow rate v, and finally completing the control circulation of the cooling system.
Compared with the prior art, the invention has the beneficial effects that:
according to the invention, through analyzing the heating source, the cooling water jackets are respectively arranged outside the bearing and the motor, so that the bearing and the motor are efficiently cooled by the cooling medium along the radial direction, in order to ensure the maximization of the cooling effect, the bearing and the motor are respectively cooled by adopting independent cooling channels, and meanwhile, the cooling water pump and the cooling water regulating valve are controlled through the feedback of the sensor, so that the supply speed and the size of the cooling liquid are controlled. Compared with the existing spindle cooling system and heat dissipation method, the spindle cooling system and the spindle cooling method can improve cooling efficiency, realize effective control of the temperature and thermal deformation of the spindle of the machine tool, overcome the defects of non-adjustable cooling, unbalanced cooling and low cooling efficiency of the traditional cooling method, and have better engineering application prospect.
Drawings
FIG. 1 is a cooling cycle system for reducing thermal errors of a spindle of a machine tool according to the present invention;
FIG. 2 is a layout view of a cooling water path of the main shaft;
FIG. 3 is a cooling system control network;
FIG. 4 is a motor cooling jacket assembly view;
FIG. 5 is a motor cooling jacket;
FIG. 6 is a bearing cooling jacket assembly view;
FIG. 7 is a bearing cooling jacket;
fig. 8 is a cooling system control flow chart.
Detailed Description
The invention is further described with reference to the accompanying drawings in which:
the invention is further described with reference to the accompanying drawings in which:
as shown in fig. 1, 2 and 3, a cooling circulation system for reducing thermal error of a machine tool spindle comprises a spindle 1, a motor is arranged in the middle section of the spindle 1, a motor rotor 6 is fixed with the spindle 1 in a hollow part of a stator 8, a motor cooling jacket 9 is sleeved outside the motor, two sets of cooling flow channels in opposite directions are arranged on the motor cooling jacket 9,
a first cold inlet pipe orifice 7 is arranged above the cooling jacket, a first hot outlet pipe orifice 15 is arranged below the cooling jacket,
the front end and the rear end of the main shaft 1 are respectively provided with a rolling bearing 2, a bearing cooling jacket 3 is sleeved outside the bearing 2, a second cold inlet pipe orifice 11 is arranged above the bearing cooling jacket 3, a second hot outlet pipe orifice 14 is arranged below the bearing cooling jacket 3,
the second cold inlet pipe orifice 11 is respectively provided with an electronic type circulating cooling water regulating valve 10, the electronic type circulating cooling water regulating valve 10 is connected with an input end main flow passage, the input end main flow passage is connected with a cooling water pump 18, the other end of the cooling water pump 18 is connected with an oil outlet of a cooling oil tank 17, an infrared temperature sensor 13 monitors the temperature of cooling liquid at the oil outlet of the cooling oil tank 17, the first hot outlet pipe orifice and the second hot outlet pipe orifice of the cooling jacket are connected with an output end main flow passage, the output end main flow passage is connected with an oil inlet of an air cooling machine 16, the oil outlet of the air cooling machine 16 is connected with the oil inlet of the cooling oil tank 17, and a main shaft 1 is provided with a Hall type rotating speed sensor 12.
The control method of the cooling circulation system comprises the following steps:
1. the heat sources for the analysis spindle part are: the friction heat of the main shaft bearing and the heat of the main shaft motor.
2. Performing main shaft heating and heat transfer analysis:
2.1, the heat generation of the bearing 2 is calculated by the following formula:
Q＝1.047×10 -4 nM (1)
wherein n is the bearing rotation speed (rpm); m is the total friction moment (N.mm) of the bearing; q is a calorific value (W).
The total friction torque of the bearing 2 comprises three parts:
M＝M 1 +M 2 +M 3 (2)
(1) Friction moment M generated by external load 1 ：
M 1 ＝f 1 F β d m (3)
Wherein f is 1 Is a coefficient determined by the bearing structure and the load, F β Is the equivalent external load and dm is the bearing mean diameter.
(2) Friction moment M generated by spin motion of roller path contact area 2 ：
Figure BDA0003035911190000081
Where μ is the coefficient of sliding friction, σ is the contact stress found at the raceway, a is the major semi-axis of the contact ellipse, and E is the complete ellipse integral of the second type.
(3) Viscous friction torque M of lubricating fluid 3 ：
Figure BDA0003035911190000091
Wherein v is 0 Is the dynamic viscosity of the lubricant, f 0 Is a factor determined by the type of bearing and the manner of lubrication.
Finishing to obtain:
Figure BDA0003035911190000092
2.2, the heat productivity of the motor is converted from the loss power of the motor, and comprises three parts:
(1) Power loss of stator 8:
P d ＝P Cu1 +P Fe (7)
wherein P is Cu For copper consumption, P Fe In order to increase the iron loss, the iron content,
Figure BDA0003035911190000093
Figure BDA0003035911190000094
wherein I 1 For stator winding line current, r 1 Is the winding resistance, I em 、r em The excitation current and the excitation resistor.
(2) The power consumption loss of the rotor 6 is similar to the copper loss:
Figure BDA0003035911190000095
wherein I 2 Is rotor current, r 2 Is rotor resistance, s is motor slip, P em Is electromagnetic power.
P em ＝P 1 -P d (11)
Wherein P is 1 Inputting power for the electric spindle:
Figure BDA0003035911190000096
wherein U is 1 Is a voltage of a stator winding line,
Figure BDA0003035911190000097
is the power factor.
(3) Stator 8 rotor 6 air gap friction losses:
P m ＝πkCρω 3 R 4 L (13)
wherein k is the roughness coefficient of the rotor surface, C is the air friction coefficient, rho is the air density, and omega, R and L are the angular speed, the radius and the axial length of the rotor respectively.
Finishing to obtain:
Figure BDA0003035911190000101
2.3 spindle Heat transfer analysis
Q＝CMΔT (15)
Wherein Q is the heat generated, C is the specific heat capacity of the material, M is the mass of the object, Δ T is the temperature rise, Δ T = T 1 -T 2 ，T 1 Is the temperature of the electric spindle, T 2 For ambient temperature, T can be solved from equation (15) 1 。
The heat dissipation of the main shaft part mainly exchanges heat with the external environment through the shell, and the heat transfer quantity of the radial heat conduction of the main shaft is as follows:
Figure BDA0003035911190000102
wherein Q cr Is the amount of heat transfer between two points, T 1 Is the temperature of the electric spindle, T 3 Is the temperature of the electric spindle housing, B is the annular width, r i 、r o Respectively the inner radius and the outer radius of the electric spindle shell.
2.4 thermal convection analysis
The forced convection heat exchange quantity generated by the cooling liquid and the surface of the shell under the external action is as follows:
Q v ＝h v S(T 5 -T 4 ) (17)
wherein Q v Is the heat flow between any two points of the cooling liquid and the shell in the process of heat convection, T 5 、T 4 The temperature of the shell surface and the cooling liquid respectively, S is the heat transfer area vertical to the heat flow direction between two points, h v Is the convective heat transfer coefficient;
Figure BDA0003035911190000111
wherein N is u Is a dimensionless parameter, λ w Is the thermal conductivity of the coolant, d c Is a characteristic length, R e Is Reynolds number, P r Is the prandtl number, ρ is the fluid density, v is the fluid flow velocity, η is the fluid flow viscosity coefficient, d is the conduit diameter, cp is the isobaric specific heat capacity, k is the thermal conductivity, μ is the kinematic viscosity.
Finishing to obtain:
Figure BDA0003035911190000112
under the ideal condition, let Q v1 ＝Q M Then the bearing coolant flow velocity v can be solved by equation (18) 1 (ii) a Let Q v2 ＝Q j Then the motor coolant flow velocity v can be solved by equation (18) 2 The effect of respectively controlling the cooling capacities of the bearing and the motor part is achieved.
3. Cooling system concrete arrangement form
As shown in fig. 4 and 6, cooling jackets 3, 9 are arranged outside the bearing 2 and the motor, and cooling jacket water paths are arranged along the radial direction of the bearing 2 and the motor.
Further, as shown in fig. 2, the first cold inlet pipe opening 7 of the motor cooling jacket 9 is arranged in the middle above the cooling jacket.
Further, as shown in fig. 5, the cooling water path in the motor cooling jacket is formed by two branches which are spirally arranged along two ends of the motor cooling jacket, so that the motor can be sufficiently cooled.
As shown in fig. 1 and 2, the cooling flow passages are arranged radially along the spindle housing 4, and the cooling flow passages of the bearing 2 and the motor are arranged independently.
As shown in fig. 3, the real-time temperature of the cooling liquid and the working state of the spindle are monitored by the infrared temperature sensor 13 and the hall rotation speed sensor 12 in real time, and the power of the cooling water pump 18 and the cooling water regulating valves 10 of each flow passage are controlled by the data processing controller 19 to control the flow rate of the cooling liquid, so as to ensure that the spindle is always at the proper working temperature.
The specific control flow is shown in fig. 8, the hall rotation speed sensor 12 monitors the rotation speed n of the main shaft, if the rotation speed n is 0, the cooling system does not work, if the rotation speed n is not 0, the next step of work is performed, the infrared temperature sensor 13 collects the real-time working temperature T1 of the cooling liquid, the flow rate v of the cooling liquid required for cooling is calculated by calculating the heat productivity of each bearing and the motor, the opening and closing degree of the cooling water regulating valve 10 and different output powers of the cooling water pump 18 are adjusted according to the calculated flow rate v of the cooling liquid, and finally, the control circulation of the cooling system is completed.
According to the invention, through analyzing a heating source, the cooling water jackets 3 and 9 are respectively arranged outside the bearing 2 and the motor, so that a cooling medium can efficiently cool the bearing 2 and the motor along the radial direction, in order to ensure the maximization of the cooling effect, the bearing 2 and the motor are respectively cooled by adopting independent cooling flow channels, and meanwhile, the cooling water pump 18 and the cooling water regulating valve 10 are controlled through the feedback of a sensor, so that the supply speed and the size of cooling liquid are controlled. Compared with the existing spindle cooling system and heat dissipation method, the spindle cooling system and the heat dissipation method can improve cooling efficiency, realize effective control of the temperature and thermal deformation of the spindle of the machine tool, overcome the defects of unadjustable cooling, unbalanced cooling and low cooling efficiency of the traditional cooling method, and have better engineering application prospect.
The specific embodiments described herein are merely illustrative of the spirit of the invention. Various modifications or additions may be made to the described embodiments or alternatives may be employed by those skilled in the art without departing from the spirit or ambit of the invention as defined in the appended claims.

Claims (1)

1. A control method of a cooling circulation system for reducing the thermal error of a machine tool spindle is characterized in that the method is suitable for the cooling circulation system for reducing the thermal error of the machine tool spindle and comprises a spindle box body and a spindle arranged in the spindle box body, wherein a motor is arranged in the middle section of the spindle, a motor cooling jacket is sleeved outside the motor, two sets of motor cooling runners in opposite directions are arranged on the motor cooling jacket, a plurality of temperature sensors are distributed on the motor, rolling bearings are respectively arranged at the front end and the rear end of the spindle, a bearing cooling jacket is sleeved outside the bearing, the spindle is provided with a rotating speed sensor, a cooling assembly is connected with the cooling runners, and a data processing controller is connected with the temperature sensors, the rotating speed sensors and the cooling assembly;
the cooling assembly comprises an air cooling machine, a cooling oil tank, a cooling water pump and an electronic circulating cooling water regulating valve which are sequentially connected; the cooling flow channel comprises a flow channel, a first cold inlet pipe orifice, a second cold inlet pipe orifice, a first hot outlet pipe orifice and a second hot outlet pipe orifice; the first cold inlet pipe orifice is arranged above the cooling jacket, the first hot outlet pipe orifice is arranged below the cooling jacket, the second cold inlet pipe orifice is arranged above the bearing cooling jacket, the second hot outlet pipe orifice is arranged below the bearing cooling jacket, and the first cold inlet pipe orifice and the second cold inlet pipe orifice are respectively provided with an electronic circulating cooling water regulating valve;
the electronic circulating cooling water regulating valve is connected with an input end main flow passage, the input end main flow passage is connected with a cooling water pump, the other end of the cooling water pump is connected with a cooling oil tank oil outlet, an infrared temperature sensor monitors the temperature of cooling liquid at the cooling oil tank oil outlet, a first hot outlet pipe orifice and a second hot outlet pipe orifice of the cooling jacket are connected with an output end main flow passage, the output end main flow passage is connected with an air cooling machine oil inlet, the air cooling machine oil outlet is connected with a cooling oil tank oil inlet, and a Hall type rotating speed sensor is mounted on the main shaft 1;
Included
step 1, analyzing the heat source of the main shaft part comprises the following steps: the friction heat of the main shaft bearing and the heat of the main shaft motor;
step 2, carrying out main shaft heating and heat transfer analysis:
step 2.1, the calorific value of the bearing 2 is calculated by the following formula:
Q＝1.047×10 -4 nM (1)
wherein n is the bearing rotation speed (rpm); m is the total friction moment (N.mm) of the bearing; q is a calorific value (W);
the total friction torque of the bearing 2 comprises three parts:
M＝M 1 +M 2 +M 3 (2)
(1) Friction moment M generated by external load 1 ：
M 1 ＝f 1 F β d m (3)
Wherein, f 1 Is a coefficient determined by the bearing structure and the load, F β Is the equivalent external load, dm is the bearing mean diameter;
(2) Friction moment M generated by spin motion of roller path contact area 2 ：
Figure FDA0003877209820000021
Wherein mu is a sliding friction coefficient, sigma is contact stress found at the raceway, a is a contact ellipse semimajor axis, and E is a second type complete ellipse integral;
(3) Viscous friction torque M of lubricating fluid 3 ：
Figure FDA0003877209820000022
Wherein v is 0 Is the dynamic viscosity of the lubricant, f 0 Is a coefficient determined by the type of bearing and the manner of lubrication;
finishing to obtain:
Figure FDA0003877209820000031
step 2.2, the heat productivity of the motor is converted from the loss power of the motor, and the method comprises three parts:
(1) Power loss of the stator 8:
P d ＝P Cu1 +P Fe (7)
wherein P is Cu For copper consumption, P Fe In order to increase the iron loss, the iron content,
Figure FDA0003877209820000032
Figure FDA0003877209820000033
in which I 1 For stator winding line current, r 1 Is the winding resistance, I em 、r em The excitation current and the excitation resistor;
(2) The power consumption loss of the rotor 6 is similar to the copper loss:
Figure FDA0003877209820000034
in which I 2 Is rotor current, r 2 Is rotor resistance, s is motor slip, P em Is the electromagnetic power;
P em ＝P 1 -P d (11)
wherein P is 1 Inputting power for the electric spindle:
Figure FDA0003877209820000035
wherein U is 1 Is a voltage of a stator winding line,
Figure FDA0003877209820000036
is the power factor;
(3) Stator 8 rotor 6 air gap friction loss:
P m ＝πkCρω 3 R 4 L (13)
wherein k is a rotor surface roughness coefficient, C is an air friction coefficient, rho is an air density, and omega, R and L are a rotor angular speed, a rotor radius and a rotor axial length respectively;
finishing to obtain:
Figure FDA0003877209820000041
step 2.3, spindle Heat transfer analysis
Q＝CMΔT (15)
Wherein Q is the heat generated, C is the specific heat capacity of the material, M is the mass of the object, Δ T is the temperature rise, Δ T = T 1 -T 2 ，T 1 Is the temperature of the electric spindle, T 2 For ambient temperature, T can be solved from equation (15) 1 ；
The heat dissipation of the main shaft part mainly exchanges heat with the external environment through the shell, and the heat transfer quantity of the radial heat conduction of the main shaft is as follows:
Figure FDA0003877209820000042
wherein Q cr Is the amount of heat transfer between two points, T 1 Is the temperature of the electric spindle, T 3 Is the temperature of the electric spindle housing, B is the annular width, r i 、r o The inner radius and the outer radius of the electric spindle shell are respectively;
step 2.4, thermal convection analysis
The forced convection heat exchange quantity generated by the cooling liquid and the surface of the shell under the external action is as follows:
Q v ＝h v S(T 5 -T 4 ) (17)
wherein Q v Is the heat flow between any two points of the cooling liquid and the shell in the process of heat convection, T 5 、T 4 The temperatures of the shell surface and the cooling liquid are respectively, S is the heat transfer area vertical to the heat flow direction between the two points, h v Is the convective heat transfer coefficient;
Figure FDA0003877209820000051
wherein N is u Is a dimensionless parameter, λ w As thermal conductivity of the cooling fluid, d c Is a characteristic length, R e Is Reynolds number, P r Is the prandtl number, ρ is the fluid density,v is the fluid flow velocity, eta is the fluid flow viscosity coefficient, d is the pipeline diameter, cp is the isobaric specific heat capacity, k is the thermal conductivity, and mu is the dynamic viscosity;
finishing to obtain:
Figure FDA0003877209820000052
under an ideal condition, let Q v1 ＝Q M Then the bearing coolant flow velocity v can be solved by equation (18) 1 (ii) a Let Q v2 ＝Q j Then the motor coolant flow velocity v can be solved by equation (18) 2 The effect of respectively controlling the cooling capacities of the bearing and the motor is achieved;
and 3, monitoring the rotation speed n of the main shaft by the Hall rotation speed sensor, if the rotation speed n is 0, enabling the cooling system to not work, if the rotation speed n is not 0, enabling the next step of work to be carried out, acquiring the real-time working temperature T1 of the cooling liquid by the infrared temperature sensor, calculating the cooling liquid flow rate v required by cooling by calculating the heat productivity of each bearing and the motor, adjusting the opening and closing degree of the cooling water regulating valve and different output powers of the cooling water pump according to the calculated cooling liquid flow rate v, and finally completing the control circulation of the cooling system.
CN202110443186.8A 2021-04-23 2021-04-23 Cooling circulation system and method for reducing thermal error of machine tool spindle Active CN113098203B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110443186.8A CN113098203B (en) 2021-04-23 2021-04-23 Cooling circulation system and method for reducing thermal error of machine tool spindle

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202110443186.8A CN113098203B (en) 2021-04-23 2021-04-23 Cooling circulation system and method for reducing thermal error of machine tool spindle

Publications (2)

Publication Number Publication Date
CN113098203A CN113098203A (en) 2021-07-09
CN113098203B true CN113098203B (en) 2023-04-07

Family

ID=76679732

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202110443186.8A Active CN113098203B (en) 2021-04-23 2021-04-23 Cooling circulation system and method for reducing thermal error of machine tool spindle

Country Status (1)

Country Link
CN (1) CN113098203B (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102021205495A1 (en) 2021-05-31 2022-12-01 Zf Friedrichshafen Ag Stator support for a stator of an electrical machine
CN114865850B (en) * 2022-07-07 2022-09-09 常州市昊升电机股份有限公司 Cooling device for motor

Also Published As

Publication number Publication date
CN113098203A (en) 2021-07-09

Similar Documents

Publication Publication Date Title
CN113098203B (en) Cooling circulation system and method for reducing thermal error of machine tool spindle
CN102713273B (en) There is the direct drive wind turbine of cooling system
CN104942649B (en) Cooling structure inside and outside a kind of high-speed electric main shaft
CN103213029B (en) A kind of high-speed turning center electro spindle cooling means and inside and outside cooling electro spindle
CN102120266A (en) High-speed precise electric spindle cooling system
CN104108047B (en) A kind of electro spindle shaft core cooling system
CN102974845A (en) High-speed electric main shaft device
CN104895846B (en) The coolant or heating fluid circulation of a kind of dual-gripper centrifugal pump
CN107247471A (en) A kind of ultra-high speed and ultraprecise air static pressure electric spindle active thermal controls system and method
CN109766647A (en) Consider that the high-performance electric main shaft timeparameter method of power thermal coupling effect determines method
CN109571134B (en) Precision machine tool spindle cooling system based on heat conduction channel and centralized heat dissipation method
Fan et al. Thermoelectric-based cooling system for high-speed motorized spindle II: Optimization and validation strategy
CN204591809U (en) A kind of cooling liquid of dual-gripper centrifugal pump or the heating fluid circulatory system
CN108923569A (en) A kind of water lubrication electric machine structure
CN116640915B (en) Roller air-cooling quenching machine
Li et al. Research on thermal deformation of feed system for high-speed vertical machining center
Fan et al. Thermoelectric-based cooling system for high-speed motorized spindle I: design and control mechanism
CN205703504U (en) A kind of high-speed electric main shaft cooling system
Jedrzejewski et al. Research on forced cooling of machine tools and its operational effects
CN203295576U (en) Water cooling roller
CN109590488A (en) Axle sleeve, electro spindle and lathe
CN106567854B (en) A kind of lubrication oil cooling structure of bearing in pump
CN2777338Y (en) Axle capable of lubricating and cooling axial bearing
CN206981769U (en) A kind of ultrahigh speed air static pressure electric spindle parallel connection cooling structure
CN207583703U (en) A kind of horizontal pump bearing cooling structure

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant
TR01 Transfer of patent right

Effective date of registration: 20230626

Address after: 441705 Wudang Road, Shihua Town, Gucheng County, Xiangyang City, Hubei Province

Patentee after: HUBEI GUCHENG COUNTY DONGHUA MACHINERY CO.,LTD.

Address before: No. 296, Luzhong Road, Xiangyang, Hubei Province

Patentee before: HUBEI University OF ARTS AND SCIENCE

TR01 Transfer of patent right