CN212496619U

CN212496619U - Automatic clamp for processing automobile bearing hub parts

Info

Publication number: CN212496619U
Application number: CN202020950197.6U
Authority: CN
Inventors: 谭满红
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-05-29
Filing date: 2020-05-29
Publication date: 2021-02-09
Anticipated expiration: 2030-05-29

Abstract

The utility model relates to an automatic clamp for processing automobile bearing wheel hub parts, a positioning seat is arranged in the middle of a bridge plate of the automatic clamp, the positioning seat is connected with the bridge plate, a plurality of clamping oil cylinder structures are also arranged on the bridge plate, all the clamping oil cylinder structures are arranged on the bridge plate in an angular distribution around the positioning seat, and each clamping oil cylinder structure comprises a connecting rod type oil cylinder and a clamping lever; the connecting rod type oil cylinder comprises an oil cylinder and a connecting rod, the oil cylinder is fixedly installed on the bridge plate, a piston rod of the oil cylinder is vertically upward, the connecting rod is connected to the end face of the side of the piston rod of the oil cylinder and is pivoted with the oil cylinder, one end of the clamping lever is a connecting end, the other end of the clamping lever is a clamping end, the clamping lever is installed on the connecting rod type oil cylinder, the connecting end is pivoted with the piston rod of the oil cylinder, the middle part of the clamping lever is pivoted with the connecting rod; the piston rod of the oil cylinder stretches out and draws back to drive the clamping lever to swing up and down, and the clamping end clamps or loosens the part to be processed on the positioning seat.

Description

Automatic clamp for processing automobile bearing hub parts

Technical Field

The utility model relates to a processing technology field, concretely relates to processing automobile bearing wheel hub part's automatic anchor clamps.

Background

Automobile manufacturing has entered an intelligent era, and the demand for parts such as bearings has further stepped into a large-batch and intelligent era, and the enormous demand quantity of parts in the market has promoted the leap development of intelligent production lines. The tool clamp is used as a part on a production line, is updated and upgraded along with the production line, and gradually develops from the traditional manual operation to semi-automatic, full-automatic and even intelligent operation. The automatic clamp has the advantages of high efficiency, manual labor reduction and the like besides the functions of positioning, supporting and fastening of the traditional clamp. The automatic fixture can be applied to a production line for producing and processing automobile bearing hubs in batches by applying the fixture to a machining center and rotating a fourth shaft.

Disclosure of Invention

The utility model provides an automatic anchor clamps of processing automobile bearing wheel hub part.

The technical scheme of the utility model:

an automatic clamp for machining automobile bearing hub parts comprises a clamp base, wherein the clamp base is installed on a workbench of a CNC machining center; a tailstock and a driver are respectively arranged on two sides of the clamp base, the tailstock is opposite to the driver, a rotating shaft of the tailstock is coaxial with an output shaft of the driver, L connecting plates are respectively and fixedly connected onto the tailstock, and a bridge plate is connected between the two L connecting plates; the bridge plate is provided with a positioning seat in the middle, the positioning seat is connected with the bridge plate, the bridge plate is also provided with a plurality of clamping oil cylinder structures, and all the clamping oil cylinder structures are distributed and installed on the bridge plate around the positioning seat; the part to be processed is placed on the positioning seat and is clamped or loosened by the synchronous action of the clamping oil cylinder structure; preferably, a 3-group connecting rod type oil cylinder structure is adopted and distributed along the circumference of the part and the positioning seat at a certain included angle, so that the workpiece is fully clamped and positioned in the axial direction, and the clamping force of the oil cylinder on the workpiece is kept balanced;

the clamping oil cylinder structure comprises a connecting rod type oil cylinder and a clamping lever; the connecting rod type oil cylinder comprises an oil cylinder and a connecting rod, the oil cylinder is fixedly installed on the bridge plate, a piston rod of the oil cylinder is vertically upward, the connecting rod is connected to the end face of the side of the piston rod of the oil cylinder and is pivoted with the oil cylinder, one end of the clamping lever is a connecting end, the other end of the clamping lever is a clamping end, the clamping lever is installed on the connecting rod type oil cylinder, the connecting end is pivoted with the piston rod of the oil cylinder, the middle part of the clamping lever is pivoted with the connecting rod, the clamping end extends into the position seat; the piston rod of the oil cylinder stretches and retracts to drive the clamping lever to swing up and down, meanwhile, the connecting rod is forced to swing back and forth to drive the clamping lever to move back and forth, and the clamping end clamps or loosens the part to be processed. The clamping end of the clamping lever is connected with a movable ball rod assembly with an automatic angle adjustment function; preferably, the bolt-type steel ball assembly of Japanese brand IMAO (Geneva) TBU-12050-S model can automatically adjust the angle thereof according to the angle of the contacted workpiece surface, the adjusting angle range is 0-12 degrees, and the clamping force is ensured to be always vertical to the normal phase of the contact of the two.

The bridge plate is also provided with an oil cylinder clamping state monitoring structure, the oil cylinder clamping state monitoring structure comprises a detection seat, a mandrel, a movable block and a floating adjusting spring, the detection seat is fixedly connected on the bridge plate, a through hole penetrating through the upper end and the lower end of the detection seat is arranged on the detection seat, the mandrel is arranged on the upper portion of the through hole, the upper end of the through hole extends out of one section of the detection seat, the movable block is arranged on the lower portion of the through hole and is in threaded connection with the detection seat, an air passage is arranged in the mandrel and penetrates through the lower end of the mandrel, the periphery of the mandrel is provided with two annular grooves from top to bottom, the two annular grooves are a first annular groove and a second annular groove in sequence, the first annular groove and the second annular groove are air grooves, air holes are arranged in the first annular groove and the second annular groove, the air grooves are connected with the, the lower end of the detection seat extends out of the mandrel and abuts against the movable block, steps are respectively arranged on the detection seat and the mandrel and are formed by matching the steps to form the axial upper limit of the mandrel, the movable block forms the axial lower limit of the mandrel, the side wall of the detection seat is provided with an air hole, and the high-pressure gas inlet is connected with an air compression station through an air passage; the oil cylinder clamping state monitoring structure further comprises a flat-head pressing bolt, the flat-head pressing bolt is fixed on a clamping lever of a clamping oil cylinder structure and is positioned above the mandrel, and the clamping lever swings up and down to drive the flat-head pressing bolt to move up and down to press the mandrel; the high-pressure gas forms pressure in the detection seat, the mandrel moves up and down under the combined action of the pressure, the flat head pressing bolt and the floating adjusting spring, the first annular groove or the second annular groove is communicated with the air hole in the detection seat, or the air hole in the detection seat is positioned between the first annular groove and the second annular groove; the clamping oil cylinder structure is loosened, and the first ring groove is communicated with the air hole in the detection seat; the clamping oil cylinder structure is clamped, the second annular groove is communicated with the air hole in the detection seat, the clamping oil cylinder structure is loosened or abnormally clamped, and the air hole in the detection seat is located between the first annular groove and the second annular groove.

The oil cylinder clamping state monitoring structure further comprises a precision barometer, and the precision barometer is connected with an air hole in the detection seat; the first ring groove is communicated with the air holes in the detection seat, the reading of a precision barometer is a, the reading of a second ring groove is communicated with the air holes in the detection seat, the reading of the precision barometer is b, the air holes in the detection seat are positioned between the first ring groove and the second ring groove, the reading of the precision barometer is c, a is greater than b and is greater than 0, and c is 0; the precise barometer is connected with a CNC (computerized numerical control) machining center through a sensor; the values are fed back to a control center of the CNC machining center through sensors, and the control center judges whether the part needs to be subjected to tool feeding machining according to the designed values.

The positioning seat is disc-shaped and is provided with a positioning groove; the bridge plate is also provided with a lateral ejection cylinder structure, the lateral ejection cylinder structure comprises a profiling stroke block, a push rod and a cylinder, the positioning seat is also provided with a push block stroke cavity, the push block stroke cavity is communicated with the positioning groove, the profiling stroke block is arranged in the push block stroke cavity, the cylinder is fixedly installed on the bridge plate through a cylinder adjusting block, the cylinder is connected with the push rod, the push rod penetrates through the positioning seat to be connected with the profiling stroke block, and the profiling stroke block is driven to be far away from or close to the positioning groove; the positioning groove is formed by connecting a circular arc-shaped thick positioning groove and a V-shaped positioning groove, and the V-shaped positioning groove is positioned on the opposite side of the pushing block stroke cavity; the air cylinder is connected with the air compression station through an air path; the arc-shaped rough positioning groove is the initial placement position of the part, when the part reaches the initial placement position, the profiling stroke block in the pushing block stroke cavity pushes the excircle of the processed part to the end point of the V-shaped positioning groove and laterally clamps the machined part, and the positioning of the part is completed; preferably, the air cylinder is provided with a travel switch, the position of the piston rod of the air cylinder is monitored in real time, when the piston rod of the air cylinder reaches the set position, the travel switch gives a feedback signal to the CNC machining center, and the machining center gives an instruction for clamping the connecting rod type clamping oil cylinder, so that the whole process of positioning and clamping the part is completed.

A plurality of bosses are distributed on the periphery of the upper surface of the positioning seat, three stepped airtight monitoring holes are distributed on the bosses along the periphery, the airtight monitoring holes are connected with an air compression station through an air passage, and a precise air pressure meter is mounted on the air passage to form an airtight inspection structure; the precise barometer is connected with a CNC (computerized numerical control) machining center through a sensor; preferably, the surface of the boss is carburized (the thickness is not less than 0.5mm) to ensure the hardness and the wear resistance of the positioning surface, the service life of the clamp is prolonged, and the production cost is reduced; the part to be machined is in contact with the boss, a small gap still exists between the part to be machined and the boss, when compressed air is introduced, most of gas is blocked in the gas path, and a small part of gas can still be leaked out of the gas tightness inspection hole, so that the leaked gas can change the gas pressure of the gas path and reduce the gas pressure.

The bridge plate is also provided with a plurality of flexible high-pressure gas nozzle structures, all the flexible high-pressure gas nozzle structures are distributed around the positioning seat in a circle, each flexible high-pressure gas nozzle structure comprises a nozzle mounting seat and a nozzle, the nozzle mounting seats are fixedly connected to the bridge plate, through holes penetrating through the nozzle mounting seats from top to bottom are formed in the nozzle mounting seats, the upper ends of the through holes are connected with pipe joints and are connected to flexible movable air pipes through the pipe joints, the lower ends of the through holes are air inlets, the nozzles are connected to the flexible movable air pipes, and the air inlets are connected with an air compression station; the flexible movable air pipe can be bent and deformed in any direction, and is deformed in the machining process, so that the direction of the nozzle is aligned to the upper surface of a machined workpiece, and the effects of removing machining residual scraps and physically cooling are achieved.

The bridge plate is a gas-liquid integrated bridge plate, and pipelines are distributed in the bridge plate to form the gas circuit and the oil circuit; the oil and gas circuits are integrated in the bridge plate, so that the space occupied by the clamp in the CNC machining center is reduced; an outlet of the air passage is opposite to and communicated with a lower port of the through hole of the detection seat, and a sealing ring is arranged between the detection seat and the bridge plate.

The oil cylinder is provided with a flow control valve and an oil cylinder exhaust valve; controlling the flow entering the oil cylinder through a flow control valve to adjust the stretching speed of the oil cylinder; air mixed with the hydraulic oil due to various reasons is discharged through the exhaust valve of the oil cylinder, and the pressure generated by the hydraulic oil is kept constant.

The CNC machining center is respectively connected with the hydraulic station and the air compression station, the CNC machining center controls the hydraulic station and the air compression station to supply oil and air, and the oil cylinder clamping structure and the lateral ejection cylinder structure are linked; automatic operation is conveniently realized.

The utility model has the advantages that the design is reasonable, the structure is simple, the processing part is clamped on the positioning seat through the clamping oil cylinder structure, thus, along with the rotation of the bridge plate, the horizontal Z-axis rotates 180 degrees in angle so as to process different parts of the upper end surface and the lower end surface of the workpiece, the procedure of re-clamping and positioning is reduced, the processing working hour is saved, and the production and processing efficiency is improved; and the residual scraps produced in the machining process are automatically unloaded due to the self gravity of the bridge plate along with the rotation of the bridge plate, so that the accumulated scraps are reduced.

Drawings

FIG. 1 is a schematic structural view of an automated jig for machining automobile bearing hub parts.

FIG. 2 is a schematic view of a partial structure of an automated fixture for machining a hub part of an automobile bearing.

Fig. 3 is a schematic view of the positioning seat structure.

Fig. 4 is a structural schematic diagram (1) of the clamping cylinder.

Fig. 5 is a structural schematic diagram (2) of the clamping cylinder.

Fig. 6 is a structural schematic diagram of a monitoring structure of a clamping state of the oil cylinder.

Fig. 7 is a structural schematic diagram of a side ejection cylinder.

Fig. 8 is a structural schematic diagram of a flexible high-pressure gas nozzle.

In the figure, a clamp base 1 tailstock 2 driver 2L connecting plate 4 bridge plate 5 positioning seat 6 circular arc-shaped thick positioning groove 6-1-1V-shaped positioning groove 6-1-2 push block stroke cavity 6-2 boss 6-3 clamping oil cylinder structure 7 connecting rod type oil cylinder 7-1 connecting rod 7-1-2 clamping lever 7-2 automatic angle adjusting and ball rod combination 7-3 oil cylinder clamping state monitoring structure 8 detection seat 8-1 mandrel 8-2 movable block 8-3 floating adjusting spring 8-4 flat head pressing bolt 8-5 lateral pushing cylinder structure 9 copying stroke block 9-1 push rod 9-2 cylinder 9-3 cylinder adjusting block 9-4 flexible high-pressure gas nozzle structure 10 nozzle mounting seat 10-1 nozzle 10-2 pipe joints 10-3 flexible active air pipes 10-4.

Detailed Description

As shown in fig. 1-8, an automated jig for machining a bearing hub part of an automobile comprises a jig base 1, wherein the jig base 1 is installed on a workbench of a CNC machining center; a tailstock 2 and a driver 2 are respectively installed on two sides of the clamp base 1, the tailstock 2 is opposite to the driver 3, a rotating shaft of the tailstock 2 is coaxial with an output shaft of the driver 3, L connecting plates 4 are respectively and fixedly connected to the tailstock 2, and a bridge plate 5 is connected between the two L connecting plates 4; a positioning seat 6 is arranged in the middle of the bridge plate 4, the positioning seat 6 is connected with the bridge plate 5, a plurality of clamping oil cylinder structures 7 are further arranged on the bridge plate 5, and all the clamping oil cylinder structures 7 are distributed and installed on the bridge plate 5 around the positioning seat 6; a part 8 to be processed is placed on the positioning seat 6 and is clamped or loosened by the clamping oil cylinder structure 7 in a synchronous action manner; the clamping oil cylinder structure 7 comprises a connecting rod type oil cylinder 7-1 and a clamping lever 7-2; the connecting rod type oil cylinder 7-1 comprises an oil cylinder 7-1-1 and a connecting rod 7-1-2, the oil cylinder 7-1-1 is fixedly installed on the bridge plate 5, a piston rod of the oil cylinder is vertically upward, the connecting rod 7-1-2 is connected to the end face of the side of the piston rod of the oil cylinder 7-1-1 and is pivoted with the oil cylinder 7-1-1, one end of the clamping lever 7-2 is a connecting end, the other end of the clamping lever is a clamping end, the clamping lever 7-2 is installed on the connecting rod type oil cylinder 7-1, the connecting end is pivoted with the piston rod of the oil cylinder 7-1-1, the middle part of the clamping lever is pivoted with the connecting rod 7-1-2, the clamping end extends into the upper part of the positioning seat 6; the clamping end of the clamping lever 7-2 is connected with a movable ball rod combination 7-3 with an automatic angle adjustment function; the bridge plate 5 is further provided with an oil cylinder clamping state monitoring structure 8, the oil cylinder clamping state monitoring structure 8 comprises a detection seat 8-1, a mandrel 8-2, a movable block 8-3 and a floating adjusting spring 8-4, the detection seat 8-1 is fixedly connected to the bridge plate 5, through holes penetrating through the upper end and the lower end of the detection seat are formed in the detection seat 8-1, the mandrel 8-2 is arranged on the upper portion of the through holes, the upper end of the through holes extends out of the outer section of the detection seat 8-1, the movable block 8-3 is arranged on the lower portion of the through holes and is in threaded connection with the detection seat 8-1, an air passage is arranged in the mandrel 8-2 and penetrates through the lower end of the mandrel 8-2, two annular grooves are arranged on the periphery of the mandrel 8-2 from top to bottom and are sequentially a first annular groove and a second annular groove, the air groove and the air passage are connected through air holes, a high-pressure air inlet is formed in the movable block 8-3 and is opposite to the air passage, the floating adjusting spring 8-4 is arranged in the air passage, the upper end of the floating adjusting spring is abutted to the mandrel 8-2, the lower end of the floating adjusting spring extends out of the mandrel 8-2 and is abutted to the movable block 8-3, steps are respectively arranged on the detection seat 8-1 and the mandrel 8-2 and are formed by matching the steps to form an axial upper limit of the mandrel 8-2, the movable block 8-3 forms an axial lower limit of the mandrel 8-2, air holes are formed in the side wall of the detection seat 8-1, and the high-pressure air inlet is connected with the air compression station through an air passage; the oil cylinder clamping state monitoring structure 8 further comprises a flat head pressing bolt 8-5, and the flat head pressing bolt 8-5 is fixed on a clamping lever of a clamping oil cylinder structure and is positioned above the mandrel 8-2; the oil cylinder clamping state monitoring structure 8 further comprises a precision barometer, and the precision barometer is connected with an air hole in the detection seat; the precise barometer is connected with a CNC (computerized numerical control) machining center through a sensor; the positioning seat 6 is disc-shaped, and a positioning groove is formed in the positioning seat 6; the bridge plate 5 is further provided with a lateral ejection cylinder structure 9, the lateral ejection cylinder structure 9 comprises a profiling stroke block 9-1, a push rod 9-2 and a cylinder 9-3, the positioning seat 6 is further provided with a push block stroke cavity 6-2, the push block stroke cavity 6-2 is communicated with the positioning groove, the profiling stroke block 9-1 is arranged in the push block stroke cavity 6-2, the cylinder 9-3 is fixedly arranged on the bridge plate 5 through a cylinder adjusting block 9-4, the cylinder 9-3 is connected with the push rod 9-2, the push rod 9-2 penetrates through the positioning groove, and the 6 is connected with the profiling stroke block 9-1; the positioning groove is formed by connecting a circular arc-shaped coarse positioning groove 6-1-1 and a V-shaped positioning groove 6-1-2; the air cylinder 9-3 is connected with an air compression station through an air path; a plurality of bosses 6-3 are distributed on the periphery of the upper surface of the positioning seat 6, three stepped airtight monitoring holes are distributed on the bosses 6-3 along the periphery, the airtight monitoring holes are connected with an air compression station through an air passage, and a precise barometer is mounted on the air passage to form an airtight inspection structure; the precise barometer is connected with a CNC (computerized numerical control) machining center through a sensor; the bridge plate 5 is also provided with a plurality of flexible high-pressure gas nozzle structures 10, all the flexible high-pressure gas nozzle structures 10 are distributed around the positioning seat 6 for a circle, each flexible high-pressure gas nozzle structure 10 comprises a nozzle mounting seat 10-1 and a nozzle 10-2, the nozzle mounting seat 10-1 is fixedly connected to the bridge plate 5 and is provided with a through hole penetrating through the nozzle mounting seat 10-1 from top to bottom, the upper end of the through hole is connected with a pipe joint 10-3 and is connected to a flexible movable air pipe 10-4 through the pipe joint 10-3, the lower end of the through hole is provided with an air inlet, the nozzle 10-2 is connected to the flexible movable air pipe 10-4, and the air inlet is connected with an air compression; the bridge plate 5 is a gas-liquid integrated bridge plate, and pipelines are distributed in the bridge plate to form the gas circuit and the oil circuit; an outlet of the air passage is opposite to and communicated with a lower port of the through hole of the detection seat 8-1, and a sealing ring is arranged between the detection seat 8-1 and the bridge plate 5.

The above disclosure is only for the preferred embodiment of the present invention, but not intended to limit itself, and any changes and modifications made by those skilled in the art without departing from the spirit of the present invention shall fall within the protection scope of the present invention.

Claims

1. An automatic clamp for machining automobile bearing hub parts comprises a clamp base, wherein the clamp base is installed on a workbench of a CNC machining center; a tailstock and a driver are respectively arranged on two sides of the clamp base, the tailstock is opposite to the driver, a rotating shaft of the tailstock is coaxial with an output shaft of the driver, L connecting plates are respectively and fixedly connected onto the tailstock, and a bridge plate is connected between the two L connecting plates; the bridge plate clamping device is characterized in that a positioning seat is arranged in the middle of the bridge plate and connected with the bridge plate, a plurality of clamping oil cylinder structures are further arranged on the bridge plate, and all the clamping oil cylinder structures are distributed and installed on the bridge plate around the positioning seat; the part to be processed is placed on the positioning seat and is clamped or loosened by the synchronous action of the clamping oil cylinder structure;

the clamping oil cylinder structure comprises a connecting rod type oil cylinder and a clamping lever; the connecting rod type oil cylinder comprises an oil cylinder and a connecting rod, the oil cylinder is fixedly installed on the bridge plate, a piston rod of the oil cylinder is vertically upward, the connecting rod is connected to the end face of the side of the piston rod of the oil cylinder and is pivoted with the oil cylinder, one end of the clamping lever is a connecting end, the other end of the clamping lever is a clamping end, the clamping lever is installed on the connecting rod type oil cylinder, the connecting end is pivoted with the piston rod of the oil cylinder, the middle part of the clamping lever is pivoted with the connecting rod, the clamping end extends into the position seat; the piston rod of the oil cylinder stretches and retracts to drive the clamping lever to swing up and down, meanwhile, the connecting rod is forced to swing back and forth to drive the clamping lever to move back and forth, and the clamping end clamps or loosens the part to be processed.

2. The automated clamp for machining automobile bearing hub parts according to claim 1, wherein the clamping end of the clamping lever is provided with a self-angle-adjusting moving ball rod assembly.

3. The automatic clamp for machining the automobile bearing hub part as claimed in claim 1, wherein the bridge plate is further provided with a cylinder clamping state monitoring structure, the cylinder clamping state monitoring structure comprises a detection seat, a mandrel, a movable block and a floating adjusting spring, the detection seat is fixedly connected to the bridge plate, a through hole penetrating through the upper end and the lower end of the detection seat is formed in the detection seat, the mandrel is arranged on the upper portion of the through hole, the upper end of the mandrel extends out of the detection seat by one section, the movable block is arranged on the lower portion of the through hole and is in threaded connection with the detection seat, an air passage is formed in the mandrel and penetrates through the lower end of the mandrel, two annular grooves are formed in the periphery of the mandrel from top to bottom, a first annular groove and a second annular groove are sequentially formed, the first annular groove and the second annular groove are air grooves, air holes are formed in the first annular groove and the second annular, the high-pressure gas inlet is right opposite to the gas passage, the floating adjusting spring is arranged in the gas passage, the upper end of the floating adjusting spring is propped against the mandrel, the lower end of the floating adjusting spring extends out of the mandrel and is propped against the movable block, the detection seat and the mandrel are respectively provided with steps and are formed by matching the steps to form the axial upper limit of the mandrel, the movable block forms the axial lower limit of the mandrel, the side wall of the detection seat is provided with a gas hole, and the high-pressure gas inlet is connected with the air compression station through a gas circuit; the oil cylinder clamping state monitoring structure further comprises a flat-head pressing bolt, the flat-head pressing bolt is fixed on a clamping lever of a clamping oil cylinder structure and is positioned above the mandrel, and the clamping lever swings up and down to drive the flat-head pressing bolt to move up and down to press the mandrel; the high-pressure gas forms pressure in the detection seat, the mandrel moves up and down under the combined action of the pressure, the flat head pressing bolt and the floating adjusting spring, the first annular groove or the second annular groove is communicated with the air hole in the detection seat, or the air hole in the detection seat is positioned between the first annular groove and the second annular groove; the clamping oil cylinder structure is loosened, the first ring groove is communicated with the air hole in the detection seat, and the clamping oil cylinder structure is clamped; the second ring groove is communicated with the air hole in the detection seat, the structure of the clamping oil cylinder is loosened or abnormally clamped, and the air hole in the detection seat is located between the first ring groove and the second ring groove.

4. The automatic clamp for machining the automobile bearing hub part as claimed in claim 3, wherein the oil cylinder clamping state monitoring structure further comprises a precision barometer, and the precision barometer is connected with an air hole on the detection seat; the first ring groove is communicated with the air holes in the detection seat, the reading of a precision barometer is a, the reading of a second ring groove is communicated with the air holes in the detection seat, the reading of the precision barometer is b, the air holes in the detection seat are positioned between the first ring groove and the second ring groove, the reading of the precision barometer is c, a is greater than b and is greater than 0, and c is 0; and the precise air pressure meter is connected with the CNC machining center through a sensor.

5. The automated jig for machining automobile bearing hub parts as claimed in claim 1, wherein the positioning seat is disc-shaped and provided with positioning grooves; the bridge plate is also provided with a lateral ejection cylinder structure, the lateral ejection cylinder structure comprises a profiling stroke block, a push rod and a cylinder, the positioning seat is also provided with a push block stroke cavity, the push block stroke cavity is communicated with the positioning groove, the profiling stroke block is arranged in the push block stroke cavity, the cylinder is fixedly installed on the bridge plate through a cylinder adjusting block, the cylinder is connected with the push rod, the push rod penetrates through the positioning seat to be connected with the profiling stroke block, and the profiling stroke block is driven to be far away from or close to the positioning groove; the positioning groove is formed by connecting a circular arc-shaped thick positioning groove and a V-shaped positioning groove, and the V-shaped positioning groove is positioned on the opposite side of the pushing block stroke cavity; the air cylinder is connected with the air compression station through an air path.

6. The automatic clamp for machining the automobile bearing hub part as claimed in claim 1, wherein a plurality of bosses are distributed on a periphery of an upper surface of the positioning seat, three stepped airtight monitoring holes are distributed on the bosses along the periphery, the airtight monitoring holes are connected with an air compression station through an air passage, and a precise air pressure gauge is mounted on the air passage to form an airtight inspection structure; and the precise air pressure meter is connected with the CNC machining center through a sensor.

7. The automated clamp for machining automobile bearing hub parts according to claim 1, wherein a plurality of flexible high-pressure gas nozzle structures are further arranged on the bridge plate, all the flexible high-pressure gas nozzle structures are distributed around the positioning seat for a circle, each flexible high-pressure gas nozzle structure comprises a nozzle mounting seat and a nozzle, the nozzle mounting seats are fixedly connected to the bridge plate, through holes penetrating through the nozzle mounting seats are formed in the bridge plate, the upper ends of the through holes are connected with pipe joints and connected to flexible movable air pipes through the pipe joints, the lower ends of the through holes are air inlets, the nozzles are connected to the flexible movable air pipes, and the air inlets are connected to the air compression station through air channels.

8. The automatic clamp for machining the automobile bearing hub part as claimed in claim 3, 6 or 7, wherein the bridge plate is a gas-liquid integrated bridge plate, and pipelines are distributed in the bridge plate to form the gas path and the oil path; an outlet of the air passage is opposite to and communicated with a lower port of the through hole of the detection seat, and a sealing ring is arranged between the detection seat and the bridge plate.

9. The automated clamp for machining automobile bearing hub parts according to claim 1, wherein the oil cylinder is provided with a flow control valve and an oil cylinder exhaust valve.

10. The automated clamp for machining automobile bearing hub parts according to claim 5, wherein the CNC machining center is connected with a hydraulic station and an air compression station respectively, oil supply and air supply of the hydraulic station and the air compression station are controlled by the CNC machining center, and the oil cylinder clamping structure and the lateral ejection cylinder structure are linked.