WO2021109341A1

WO2021109341A1 - Knife handle with honeycomb sealing structure for liquid nitrogen in hollow structure

Info

Publication number: WO2021109341A1
Application number: PCT/CN2020/077099
Authority: WO
Inventors: 刘阔; 班仔优; 王永青; 韩灵生; 孔繁泽; 王思琪
Original assignee: 大连理工大学
Priority date: 2019-12-02
Filing date: 2020-02-28
Publication date: 2021-06-10
Also published as: CN110883592B; CN110883592A

Abstract

Disclosed is a knife handle with a honeycomb sealing structure for conveying liquid nitrogen in a hollow structure. The knife handle comprises a knife handle main body (1), a peripheral static structure, a multi-layer sealing structure, a heat insulation structure and support structures at two ends of a bearing. The knife handle main body (1) comprises an annular groove (1-h), wherein the annular groove (1-h) is in sequential communication with a first internal runner (1-a) and a second internal runner (1-n), the first internal runner (1-a) being a circular hole runner at an inclined angle with respect to a horizontal plane; the multi-layer sealing structure comprises a peripheral labyrinthic sealing structure, a honeycomb sealing structure, a contact-type sealing ring and an end face sealing member; honeycomb sealing is used between an adapter sleeve (2.3) of the peripheral static structure and the knife handle main body (1), and the peripheral labyrinthic sealing structure (4.2) is used between a heat insulation housing (2.2) of the heat insulation structure and a peripheral sealing ring (4.3) of the multi-layer sealing structure. According to the knife handle, liquid nitrogen is transported from a storage tank, through the interior of the knife handle, to a cutting area, and thus the problems of existing knife handles wherein the liquid-nitrogen sealing and heat insulation performances of same are insufficient, and there is severe friction at an end face thereof caused by single-end support of the knife handle during operation are solved.

Description

A honeycomb sealing structure knife handle for hollow transportation of liquid nitrogen

Technical field

The invention belongs to the technical field of tool holders for numerical control machine tools, and particularly relates to a honeycomb seal structure tool holder for hollow conveying of liquid nitrogen.

Background technique

With the development of the aerospace industry, people have higher and higher performance requirements for aerospace equipment. Therefore, titanium alloys, high-temperature alloys and other difficult-to-process materials with excellent properties such as high temperature resistance and corrosion resistance have become parts and components of high-end equipment fields such as aerospace The key materials used at the time. However, these difficult-to-machine materials usually exhibit characteristics such as high viscosity, high toughness, and anisotropy. It is difficult to achieve good cutting results with conventional cutting. Experiments have shown that applying ultra-low temperature medium such as liquid nitrogen to the local cutting area can effectively reduce the extremely high cutting heat of titanium alloy and other difficult-to-machine materials in the cutting process, improve the cutting performance of the material, increase the tool life, and replace the traditional cutting fluid to achieve green manufacture. This cutting method that uses liquid nitrogen as a coolant and lubricant is called ultra-low temperature cutting.

For the current ultra-low temperature cutting, there are mainly two types of ultra-low temperature medium supply methods, internal injection and external injection. The external spray type supply can be realized by only improving the design of the tool holder, and it has become the main method of ultra-low temperature medium supply at present. The external spray type supply can be realized by only the external medium supply and spray device, and it has become the main method of low-temperature medium supply at present. However, the cooling and lubrication efficiency of external spray supply is not high, and it is impossible to accurately and efficiently cool and lubricate the cutting area. Therefore, the use of outer-rotating inner tool holders in the low-temperature cooling and lubrication method can not only solve the problem of low cooling efficiency, but also be suitable for low-temperature processing of traditional CNC machine tools.

In 2014, Wang Fengbiao and others disclosed a liquid nitrogen internal spray type tool holder device in patent CN201410228633.8. The tool holder is directly connected with the liquid nitrogen supply system to realize ultra-low temperature processing. However, the device cannot solve the problem of liquid nitrogen sealing well, and it is easy to cause lubrication and freezing of the inner bearing of the knife handle and frost on the outer surface, which causes the knife handle to stop rotating, which is inconvenient to operate. In 2019, Wang Yongqing and others disclosed in CN201910084476.0 a tool holder suitable for cooling and lubrication of ultra-low temperature media. The device adds a labyrinth sealing structure to solve the sealing problem of liquid nitrogen. However, the tool holder structure is supported by a single-ended bearing, the tool holder has insufficient rigidity and the sealing effect of the labyrinth seal is not ideal under the limited size.

technical problem

The main technical problem solved by the present invention is to overcome the shortcomings of the existing tool holder device. Aiming at the problems of insufficient bearing support rigidity and unsatisfactory sealing effect of the existing externally rotating internally cooled tool holder, a method for hollow transportation of liquid nitrogen is invented Honeycomb seal structure knife handle.

Technical solutions

The technical scheme of the present invention:

A honeycomb sealing structure knife handle for hollow conveying of liquid nitrogen includes a knife handle main body 1, a peripheral static structure, a multilayer sealing structure, a heat insulation structure, and a supporting structure at both ends of the bearing;

The left end of the tool holder body 1 is a tapered surface 1-d, which is used to cooperate with the spindle head 6.2 of the machine tool to realize the positioning of the tool holder; the end of the tapered surface 1-d is perpendicular to the tapered surface 1-d with internal thread of the tool holder. 1-c; the extension of the tapered surface 1-d is provided with a flange 1-b; the right end of the shank body 1 is a stepped shaft, with a shoulder 1-e of the stepped shaft and a shoulder two 1-e of the stepped shaft j. Tool shank external thread 1-f, tool shank external thread 2-k and tool shank external thread 3-m, and tool shank external thread 1-f is located on the shoulder 1-e of the stepped shaft and the stepped shaft Between shoulder two 1-j of the shank, the external thread two 1-k of the shank and the external thread three 1-m of the shank are located at the right end of the shoulder two 1-j of the stepped shaft, which is used for the main body 1 of the tool shank and other structures Between the positioning and installation; the stepped shaft surface at the right end of the tool holder body 1 is provided with a sealing groove 1-g on the shaft, a sealing groove 2-i on the shaft and an annular groove 1-h, and the annular groove 1-h is located on the shaft for sealing Between the groove 1-g and the seal groove 2-i on the shaft; the annular groove 1-h communicates with the internal flow passage 1-a, and the internal flow passage 1-a is a circular hole flow passage inclined at an angle to the horizontal plane. The inlet is connected to the annular groove 1-h; the inclination angle of the internal flow channel 1-a is used to reduce the pressure drop loss of liquid nitrogen during the flow process; the internal flow channel 1-a communicates with the internal flow channel 2-n, and Runner 2 1-n is a horizontal circular hole runner, located at the right end inside the main body of the tool holder. The liquid nitrogen L exiting from the internal runner 2 1-n will enter the internal runner 6.6-a of the hollow internal cooling tool 6.6 ；

The peripheral static structure is mainly composed of a metal shell 2.1, a heat-insulating shell 2.2 and an adapter sleeve 2.3; the metal shell 2.1 has a positioning shoulder 2.1-a inside which is positioned with the outer end faces of the left end bearing 5.1 and the adapter sleeve 2.3 respectively ; The heat-insulating shell 2.2 is made of materials with low thermal conductivity. The heat-insulating shell 2.2 has a sealing tooth structure 2.2-a and an internal end surface 2.2-b, of which the internal end surface 2.2-b is used for the positioning and compression of the right end bearing 5.5 ; The adapter sleeve 2.3 is made of materials with low thermal conductivity and is sleeved on the outside of the shaft surface where the annular groove 1-h on the outer surface of the tool holder body 1 is located; the adapter sleeve 2.3 has an internal threaded hole 2.3-a on the outer surface for use It is connected to the external threaded joint 6.4-a of the transport insulation hose 6.4 of the external liquid nitrogen transport system; the inner surface of the adapter sleeve 2.3 is provided with an arc groove 2.3-c and the outer surface of the tool holder body 1 is opposite to the annular groove 1-h Match to form part of the internal flow channel; liquid nitrogen L flows in through the internal threaded hole 2.3-a, temporarily stored and buffered in the arc-shaped groove 2.3-c, and then flows into the internal flow channel 1-a of the tool holder body ; The adapter sleeve 2.3 has an end shoulder 2.3-e, which is used for the positioning support of the right end bearing 5.5; the left and right sides of the arc groove 2.3-c of the adapter sleeve 2.3 are respectively installed with a honeycomb belt 2.3-b and honeycomb Belt two 2.3-d; honeycomb belt one 2.3-b and honeycomb belt two 2.3-d are made of thin plates, composed of multiple rows and rows of hexagonal honeycomb holes whose inner surface is honeycomb shape, and an adapter sleeve 2.3 Interference fit is adopted between them and they are fixed by welding;

The heat-insulating structure is mainly composed of heat-insulating filling material 3.1, inner runner heat-insulating bushing 3.2, inner runner heat-insulating bushing 2 3.3, and heat-insulating shell 2.2; the heat-insulating structure adopts materials with low thermal conductivity. It is made to prevent the influence of low temperature on the structure of the tool holder when the liquid nitrogen L flows through the internal flow channel 1-a and the internal flow channel 2- 1-b; the insulating filler material 3.1 is wrapped on the outside of the metal shell 2.1, It is compressed by the heat-insulating shell 2.2; the inner runner heat-insulating bushing 3.2 is installed in the inclined inner runner 1-a of the tool holder body 1, and the inner runner heat-insulating bushing 3.3 is installed in the horizontal interior. In the runner two 1-n, it is used to reduce the heat loss when the liquid nitrogen L flows in the tool holder body 1; the heat insulation shell 2.2 is installed on the outside of the heat insulation filling material 3.1, and the metal shell 2.1 is connected by bolts for compaction; The heat-insulating shell 2.2 helps prevent the liquid nitrogen L sprayed from the inner runner 6.6-a of the hollow inner cooling tool 6.6 from affecting the right end bearing 5.5, and prevents it from frosting and stalling;

The multi-layer sealing structure is mainly composed of end face seal 4.1, peripheral labyrinth sealing structure 4.2, peripheral sealing ring 4.3, sealing ring right gland 4.4, contact sealing ring 4.5, internal honeycomb sealing structure 4.6, and internal honeycomb sealing structure Two 4.7, contact seal ring two 4.8 and seal ring left gland 4.9 composition; the end face seal 4.1 is made of high temperature resistant, low thermal conductivity materials, used to prevent liquid nitrogen L and hollow internal cooling tool 6.6 contact and leakage The outer labyrinth sealing structure 4.2 is composed of the sealing tooth structure 2.2-a of the heat-insulating shell 2.2 and the outer sealing ring 4.3, which is used to increase the resistance of leakage flow and prevent the liquid nitrogen L sprayed from the hollow inner cooling tool 6.6 to the right end bearing 5.5 Impact; the outer sealing ring 4.3 is made of a material with low thermal conductivity, and is connected with the outer thread of the shank on the shaft end of the shank body 1 through the internal thread 2-k; the internal honeycomb sealing structure 4.6 is sealed by the shaft on the groove Two 1-i and honeycomb belt two 2.3-d are used to increase the resistance to leakage flow and improve the sealing effect on liquid nitrogen L; the internal honeycomb sealing structure two 4.7 consists of the on-axis sealing groove one 1-g and the honeycomb belt one 2.3- b composition, used to increase the resistance of leakage flow and improve the sealing effect of liquid nitrogen L; the right gland 4.4 of the sealing ring and the left gland 4.9 of the sealing ring are respectively distributed on both sides of the outer surface of the adapter sleeve 2.3, and the adapter sleeve 2.3 They are connected by bolts respectively, with a compression contact seal ring 4.5 and a contact seal ring two 4.8; the contact seal ring one 4.5 and the contact seal ring two 4.8 are made of materials with low thermal conductivity and high temperature resistance. Used to prevent liquid nitrogen from leaking into the internal bearing system and ensure the normal operation of bearing components;

The supporting structure at both ends of the bearing is mainly composed of a left end bearing 5.1, a bearing gland 5.2, a bearing sleeve 5.3, a tightening nut 5.4, and a right end bearing 5.5; the supporting structure at both ends of the bearing adopts the method of supporting at both ends to improve the handle Dynamic performance; the left end bearing 5.1 is installed on the shoulder 1-e of the stepped shaft of the tool holder body 1, and the bearing sleeve 5.3 is sequentially inserted from the right end of the tool holder body 1 and locked by the tightening nut 5.4 to produce a preset The tightening force realizes the fixing of the left end bearing 5.1 on the outer surface of the stepped shaft of the tool holder body; the end face of the right end bearing 5.5 is in contact with the end face shoulder 2.3-e of the adapter sleeve 2.3 to achieve positioning, and depends on the inner end face 2.2- of the heat-insulating shell 2.2- b Realize compaction; both the left end bearing 5.1 and the right end bearing 5.5 adopt bearings with a contact seal ring type.

The tool holder connecting frame 6.3 has one end fixed on the outer circular surface of the heat-insulating shell 2.2, and the other end is connected with the stationary components of the machine tool to ensure that the external structure of the low-temperature and micro-lubricated tool holder and the machine tool remain stationary; the spindle head of the machine tool 6.2 is located At the end of the machine tool spindle, when the honeycomb seal structure tool holder transported by liquid nitrogen is used, the taper surface 1-d of the tool holder body 1 and the machine tool spindle head 6.2 are positioned and installed through the pull nail 6.1; the transportation insulation hose 6.4 is connected to the outside The liquid nitrogen L supply system is connected to the tool holder through the external thread 6.4-a of the insulated hose connector, so that the liquid nitrogen L enters the tool holder from the supply system; the liquid nitrogen L finally enters the hollow internally cooled tool installed at the end of the tool holder 6.6, and spray into the cutting area through the tool's internal flow channel 6.6-a; the hollow internal cooling tool 6.6 relies on the taper surface of the elastic collet 6.5 and the inner taper surface of the right end of the shank body 1 for positioning, and then relies on the thread and the external thread of the shank Three 1-m for clamping installation.

Beneficial effect

The beneficial effect of the present invention is that it solves the problems of the existing liquid nitrogen internal spray type knife handle for liquid nitrogen sealing, insufficient heat insulation performance and serious end face friction caused by the single-end support of the knife handle, and improves the utilization rate of liquid nitrogen. The use performance and life of the tool holder are improved, and the safety is high, and the operation is convenient. It can be applied to CNC machine tools to realize internal spray type ultra-low temperature cutting processing.

Description of the drawings

Fig. 1 is a cross-sectional view of the inside of the main body of the honeycomb sealing structure knife handle for hollow conveying of liquid nitrogen;

Figure 2 is an internal cross-sectional view of a honeycomb sealing structure knife handle used for hollow conveying of liquid nitrogen;

Figure 3 is a cross-sectional view of the adapter sleeve 2.3 of the honeycomb seal structure knife handle for hollow conveying of liquid nitrogen;

Figure 4 is a view from the direction A of the adapter sleeve 2.3 honeycomb belt 2.3-b;

Figure 5 is a partial view of the honeycomb sealing structure between the adapter sleeve 2.3 and the handle body 1;

Fig. 6 is a schematic diagram of assembling a honeycomb sealing structure knife handle for hollow conveying of liquid nitrogen;

In the picture: 1 main body of the tool holder; 1-a internal runner; 1-b flange; 1-c internal thread of the tool holder; 1-d tapered surface; 1-e stepped shaft shoulder; 1-f knife Shank external thread one; 1-g shaft sealing groove one; 1-h annular groove; 1-i shaft sealing groove two; 1-j stepped shaft shoulder two; 1-k tool shank external thread two; 1- m tool holder external thread three; 1-n internal runner two; internal runner one 1-a inclination angle; 2.1 metal shell; 2.1-a positioning shoulder; 2.2 heat insulation shell; 2.2-a sealing tooth structure; 2.2 -b internal end face; 2.3 adapter sleeve; 2.3-a internal threaded hole; 2.3-b honeycomb belt one; 2.3-c arc groove; 2.3-d honeycomb belt two; 2.3-e end face shoulder; 3.1 insulation filling material ; 3.2 Inner runner heat insulation bushing one; 3.3 Inner runner heat insulation bushing two; 4.1 end seals; 4.2 peripheral labyrinth sealing structure; 4.3 peripheral sealing ring; 4.4 sealing ring right gland; 4.5 contact sealing ring one 4.6 Internal honeycomb seal structure one; 4.7 Internal honeycomb seal structure two; 4.8 Contact seal ring two; 4.9 Seal ring left gland; 5.1 left end bearing; 5.2 bearing gland; 5.3 bearing sleeve; 5.4 tightening nut; 5.5 right end Bearing; 6.1 pull nail; 6.2 machine tool spindle head; 6.3 tool holder connecting frame; 6.4 transportation heat insulation hose; 6.4-a external thread joint; 6.5 elastic collet; 6.6 hollow internal cooling tool; 6.6-a tool internal flow path; L liquid nitrogen.

Embodiments of the present invention

The specific embodiments of the present invention will be described in detail below with reference to the drawings and technical solutions.

A honeycomb sealing structure knife handle for hollow conveying of liquid nitrogen is improved on the basis of the traditional knife handle structure. As shown in Figure 2, it includes a tool holder body, a peripheral static structure, a multilayer sealing structure and a heat insulation structure, and a supporting structure at both ends of the bearing.

As shown in Figure 2, during installation, install the inner runner heat-insulating bushing 3.2 at low temperature into the inner runner 1-a of the knife handle, and cold-fit the inner runner heat insulating bushing 3.3 at low temperature. Insert the inner runner 2 1-n of the tool holder, and then match the end face seal 4.1 with the inner runner heat insulation bushing 2 3.3 to complete the installation of the heat insulation seal structure in the inner runner; install the left end bearing 5.1 according to the tool holder body 1 Position the shoulder 1-e of the stepped shaft, and install the bearing sleeve 5.3 in turn. The tightening nut 5.4 provides pre-tightening force for the left end bearing 5.1; install the honeycomb belt one 2.3-b and honeycomb belt two 2.3-d into the structure The base body is the adapter sleeve 2.3, and then match the arc groove 2.3-c with the annular groove 1-h on the shaft correspondingly, and use the right sealing ring gland 4.4 and the sealing ring left gland 4.9 to respectively set the contact seal ring to 4.5 And contact seal ring two 4.8 are pressed on the left and right sides of the adapter sleeve 2.3; rely on the inner positioning shoulder 2.1-a of the metal shell 2.1 and the left end bearing 5.1 to fit into the metal shell 2.1; use the end shaft of the adapter sleeve 2.3 Shoulder 2.3-e position and install the right end bearing 5.5; rely on the cooperation of the inner thread of the outer sealing ring 4.3 and the outer thread of the tool holder 2-k to tighten the outer sealing ring 4.3; wrap the insulating filler material 3.1 around the metal shell 2.1, install Into the insulated enclosure 2.2, and tighten all the bolts on the enclosure to provide sufficient compression force. The above steps have completed the installation of the honeycomb seal structure tool holder for the hollow transportation of liquid nitrogen.

As shown in Figure 1, 2, 3, 4, 5, 6, in order to ensure that the assembled tool holder can meet the performance requirements in actual processing, such as sealing requirements, processing accuracy, etc., it is necessary to ensure the assembly accuracy between the components. 1. There is an interference fit between the inner ring of the bearing and the main body of the tool holder, and between the contact seal ring and the tool holder, and the coaxiality is required. 2. The end face that is positioned and in contact with the bearing needs to ensure the verticality requirements of the end face; 3. The contact surface of the end face seal 4.1 and the hollow internal cooling tool 6.6 must have flatness requirements to ensure the accuracy of the tool positioning. 4. The design of the flow channel 1-a inside the main body of the tool holder. Reasonable design of the inclination angle of the flow channel can reduce the pressure loss of liquid nitrogen in the flow channel. 5. Interference fit is adopted between the honeycomb belt 2.3-b, the honeycomb belt 2.3-d and the adapter sleeve 2.3. 6. Processing requirements of honeycomb belt. The honeycomb tape needs to ensure the complete surface shape and strength to meet the sealing requirements.

The operation mode of the tool holder device is as follows:

(1) As shown in Figure 5, during processing, insert the hollow inner cooling tool 6.6 along the center hole of the elastic collet 6.5, and tighten the elastic collet 6.5 through the external thread of the tool holder to complete the installation of the elastic collet 6.5;

(2) As shown in Figure 1 and Figure 6, install the tool holder with the tool into the taper hole of the spindle head 6.2 of the machine tool, screw the pull pin 6.1 into the internal thread 1-c of the tool holder, and then tighten the tool holder so that The tapered surface 1-d of the tool holder body 1 is in close contact with the tapered surface of the spindle head 6.2 of the machine tool to complete the installation and positioning of the tool holder; the tool holder is fixed on the machine bed through the tool holder connecting frame 6.3;

(3) Turn on the spindle motor, the main body of the tool holder, the supporting structure at both ends of the bearing, the inner runner heat-insulating bushing 3.2, the inner runner heat-insulating bushing 3.3, the end face seal 4.1, the elastic collet 6.5 and the hollow inner The cold tool 6.6 rotates and feeds with the main shaft to realize cutting; the peripheral main structure, the multilayer sealing structure and the transportation heat insulation hose 6.4, the machine bed remains stationary;

(4) As shown in Figure 5, the transmission control system of liquid nitrogen L is turned on to automatically transport the medium. The liquid nitrogen flows through the internal flow channel 1-a and the internal flow channel two 1-n, and then enters the hollow internal cooling tool 6.6, and finally passes The tool internal runner 6.6-a of the hollow internal cooling tool 6.6 is sprayed onto the cutting area to realize the external rotation and internal flow of liquid nitrogen for low-temperature processing.

It should be noted that the above-mentioned specific embodiments of the present invention are only used to exemplify the principles and procedures of the present invention, and do not constitute a limitation to the present invention. Therefore, any modifications and equivalent replacements made without departing from the spirit and scope of the present invention should be included in the protection scope of the present invention.

Claims

A honeycomb sealing structure tool holder for hollow conveying of liquid nitrogen includes a tool holder main body (1), a peripheral static structure, a multilayer sealing structure, a heat insulation structure, and a supporting structure at both ends of the bearing;

The left end of the tool holder body (1) is a tapered surface (1-d), which is used to cooperate with the spindle head (6.2) of the machine tool to realize the positioning of the tool holder; the end of the tapered surface (1-d) is perpendicular to the tapered surface ( 1-d) There is an internal thread (1-c) of the tool holder; a flange (1-b) is provided at the extension of the tapered surface (1-d); the right end of the tool holder body (1) is a stepped shaft with Shoulder one (1-e) of stepped shaft, shoulder two (1-j) of stepped shaft, external thread one (1-f) of shank, external thread two (1-k) of shank and external thread of tool shank Three (1-m), the shank external thread one (1-f) is located between the shoulder one (1-e) of the stepped shaft and the shoulder two (1-j) of the stepped shaft, the external thread of the tool shank two ( 1-k) and the third external thread of the tool holder (1-m) are located at the right end of the second shoulder (1-j) of the stepped shaft, used for positioning and installation between the tool holder body (1) and other structures of the tool holder; The surface of the stepped shaft at the right end of the shank body (1) is provided with a seal groove on the shaft (1-g), a seal groove on the shaft (1-i) and an annular groove (1-h). The annular groove (1-h) is located on the shaft. Between the upper seal groove one (1-g) and the shaft seal groove two (1-i); the annular groove (1-h) communicates with the internal flow channel one (1-a) and the internal flow channel one (1-a) It is a circular hole flow channel with an inclined angle to the horizontal plane, and its inlet is connected with the annular groove (1-h); the inclination angle of the internal flow channel (1-a) is used to reduce the pressure drop loss of the liquid nitrogen during the flow; the internal flow Channel one (1-a) communicates with internal runner two (1-n), internal runner two (1-n) is a horizontal circular hole runner, located at the right end inside the main body of the tool, from the internal runner two (1-n) The liquid nitrogen (L) going out will enter the internal flow channel (6.6-a) of the hollow inner cooling tool (6.6);

The peripheral static structure is mainly composed of a metal shell (2.1), a heat-insulating shell (2.2) and an adapter sleeve (2.3); the metal shell (2.1) has a positioning shaft shoulder (2.1-a) inside, which is connected to the left end bearing ( 5.1) and the outer end face of the adapter sleeve (2.3); the heat-insulating shell (2.2) is made of materials with low thermal conductivity, and the heat-insulating shell (2.2) has a sealing tooth structure (2.2-a) and the inner end face (2.2-b), in which the inner end surface (2.2-b) is used for positioning and pressing the right end bearing (5.5); the adapter sleeve (2.3) is made of materials with low thermal conductivity and is sleeved on the handle body (1) The outer surface of the annular groove (1-h) is located on the outside of the shaft surface; the outer surface of the adapter sleeve (2.3) is provided with an internal threaded hole (2.3-a), which is used to transport the heat insulation hose ( 6.4) The external threaded joint (6.4-a) is connected; the inner surface of the adapter sleeve (2.3) is provided with an arc groove (2.3-c) to match the annular groove (1-h) on the outer surface of the tool holder body (1), It forms part of the internal flow channel; the liquid nitrogen (L) flows in through the internal threaded hole (2.3-a), is temporarily stored and buffered in the arc groove (2.3-c), and then flows into the internal flow channel one of the main body of the tool holder (1-a); the adapter sleeve (2.3) has an end shoulder (2.3-e), which is used for the positioning support of the right end bearing (5.5); the arc groove (2.3-c) of the adapter sleeve (2.3) The left and right sides are respectively installed with honeycomb belt one (2.3-b) and honeycomb belt two (2.3-d); honeycomb belt one (2.3-b) and honeycomb belt two (2.3-d) are made of thin plates, which are made of The inner hole surface of multiple rows and multiple rows is composed of honeycomb-shaped hexagonal honeycomb holes, which are matched with the adapter sleeve (2.3) by interference fit and fixed by welding;

The thermal insulation structure is mainly composed of thermal insulation filling material (3.1), inner runner thermal insulation bushing one (3.2), internal runner thermal insulating bushing two (3.3) and thermal insulation shell (2.2); The structure is made of materials with low thermal conductivity, which is mainly to prevent the influence of low temperature on the structure of the tool holder when the liquid nitrogen (L) flows through the internal runner one (1-a) and the internal runner two 1-b; The thermal filling material (3.1) is wrapped on the outside of the metal shell (2.1) and is pressed by the heat-insulating shell (2.2); the inner runner heat-insulating bushing (3.2) is installed in the inclined inner part of the handle body (1) The runner one (1-a) and the inner runner heat insulation bushing two (3.3) are installed in the horizontal internal runner two (1-n) to reduce the liquid nitrogen (L) in the handle body (1). ) Heat loss when flowing inside; the thermal insulation shell (2.2) is installed on the outside of the thermal insulation filling material (3.1), and the metal shell (2.1) is connected by bolts for compaction; the thermal insulation shell (2.2) helps prevent the hollow The influence of the liquid nitrogen (L) sprayed from the inner runner (6.6-a) of the inner cooling tool (6.6) on the right end bearing (5.5) to prevent it from frosting and stopping;

The multi-layer sealing structure is mainly composed of end face seal (4.1), peripheral labyrinth seal structure (4.2), peripheral sealing ring (4.3), right gland of sealing ring (4.4), contact sealing ring one (4.5), internal Honeycomb seal structure one (4.6), internal honeycomb seal structure two (4.7), contact seal ring two (4.8) and seal ring left gland (4.9); end face seal (4.1) adopts high temperature resistance and low thermal conductivity Made of material, used to prevent liquid nitrogen (L) and hollow inner cooling tool (6.6) from leaking when contacting and matching; the outer labyrinth sealing structure (4.2) consists of the sealing tooth structure (2.2-a) of the heat-insulating shell (2.2) and the periphery The sealing ring (4.3) is formed to increase the resistance to leakage and flow to prevent the impact of the liquid nitrogen (L) sprayed from the hollow inner cooling tool (6.6) on the right end bearing (5.5); the outer sealing ring (4.3) has a low thermal conductivity It is made of material, and is connected with the outer thread of the shank (1-k) on the shaft end of the shank body (1) through the internal thread; the internal honeycomb sealing structure one (4.6) is composed of the sealing groove on the shaft (1-k) i) and honeycomb belt two (2.3-d), used to increase the resistance of leakage flow and improve the sealing effect to liquid nitrogen (L); the internal honeycomb sealing structure two (4.7) consists of a sealing groove on the shaft (1-g) And honeycomb belt one (2.3-b), used to increase the resistance of leakage flow and improve the sealing effect on liquid nitrogen (L); the right gland (4.4) of the sealing ring and the left gland (4.9) of the sealing ring are respectively distributed in the rotation The two sides of the outer surface of the adapter sleeve (2.3) are connected with the adapter sleeve (2.3) by bolts to compress the contact seal ring one (4.5) and the contact seal ring two (4.8); the contact seal ring The first (4.5) and the second (4.8) contact seal ring are made of materials with low thermal conductivity and high temperature resistance, which are used to prevent liquid nitrogen from leaking into the internal bearing system and ensure the normal operation of the bearing assembly;

The supporting structure at both ends of the bearing is mainly composed of the left end bearing (5.1), the bearing gland (5.2), the bearing sleeve (5.3), the tightening nut (5.4) and the right end bearing (5.5); the supporting structure at both ends of the bearing adopts The method of supporting at both ends improves the dynamic performance of the tool holder; the left end bearing (5.1) is installed on the shoulder one (1-e) of the stepped shaft of the tool holder body (1), from the right end of the tool holder body (1) Put the bearing sleeve (5.3) into the bearing sleeve (5.3) and lock it by the tightening nut (5.4) to generate pre-tightening force to realize the fixation of the left end bearing (5.1) on the outer surface of the stepped shaft of the tool holder body; the end surface of the right end bearing (5.5) and The end face shoulder (2.3-e) of the adapter sleeve (2.3) is in contact with each other to achieve positioning, and the inner end face (2.2-b) of the heat-insulating shell (2.2) is used for compression; left end bearing (5.1) and right end bearing (5.5) All bearings with contact seal ring type are used;

The said tool holder connecting frame (6.3), one end is fixed on the outer circular surface of the heat-insulating shell (2.2), and the other end is connected with the stationary components of the machine tool to ensure that the external structure of the low-temperature and micro-lubricated tool holder and the machine tool remain stationary; The spindle head (6.2) is located at the end of the spindle of the machine tool. When the tool holder with honeycomb seal structure transported by liquid nitrogen is used, the taper (1-d) of the main body (1) of the tool holder (1) and the spindle head ( 6.2) Positioning and installation; the transportation insulated hose (6.4) is externally connected to the liquid nitrogen (L) supply system, and is connected to the tool holder through the external thread of the insulated hose connector (6.4-a) to make liquid nitrogen (L) Enter the tool holder from the supply system; liquid nitrogen (L) finally enters the hollow internal cooling tool (6.6) installed at the end of the tool holder, and is sprayed into the cutting area through the tool internal runner (6.6-a); the hollow internal cooling tool (6.6) ) Rely on the tapered surface of the elastic collet (6.5) and the inner tapered surface of the right end of the tool holder body (1) for positioning, and then rely on the thread and the external thread of the tool holder (1-m) for clamping and installation.