CN210848387U

CN210848387U - High-precision three-jaw centering mechanism with air gap detection function

Info

Publication number: CN210848387U
Application number: CN201921829077.4U
Authority: CN
Inventors: 吴长江; 张树财; 于跃; 黄耀明; 林文森; 何庆洋
Original assignee: Dalian Dongfang Special Machine Co ltd
Current assignee: Dalian Dongfang Special Machine Co ltd
Priority date: 2019-10-29
Filing date: 2019-10-29
Publication date: 2020-06-26
Anticipated expiration: 2029-10-29

Abstract

The utility model discloses a take high accuracy three-jaw centering mechanism of air gap detection, its characterized in that: centering mechanism include casing (1), sliding connection has drive shaft (2) in casing (1), be connected with piston (3) on drive shaft (2), piston (3) are located the hydraulic pressure chamber of seting up in casing (1), and the tip of drive shaft (2) is the taper, has three round pin (5) that rise through oblique dovetail mechanism (4) sliding connection on it, the axis of the round pin that rises (5) is mutually perpendicular with the axis of drive shaft (2), rises round pin (5) sliding connection simultaneously in casing (1), the contained angle between dovetail and the horizontal plane in the oblique dovetail mechanism (4) is 4-8. The high-precision three-jaw centering mechanism is simple in structure, ingenious in design, reasonable in layout, capable of automatically centering a crankshaft while clamping, and capable of judging whether the crankshaft is clamped in place through air detection and having the function of detecting air gaps.

Description

High-precision three-jaw centering mechanism with air gap detection function

Technical Field

The utility model relates to a frock clamp with centering function, especially a take high accuracy three-jaw centering mechanism of air gap detection.

Background

When the finish machining of the crankshaft hole of the engine is carried out, the crankshaft needs to be positioned and clamped firstly, and meanwhile, the central axis of the clamped crankshaft hole is kept accurate and consistent with the theoretical central axis during machining. In order to achieve the above purpose, conventionally, a crankshaft is adjusted by a centering mechanism, and then clamped and fixed by a clamp on the premise of keeping the spatial position of the crankshaft unchanged. The operation is relatively cumbersome and requires a large amount of work.

Meanwhile, in the finish machining process, the stability of the centering mechanism must be ensured, namely the clamp always needs to be kept in a good clamping state, and if the clamp loosens, processing waste products may occur;

there is therefore a need for a method or apparatus that addresses the above-mentioned problems.

Disclosure of Invention

The utility model relates to a solve the above-mentioned not enough that prior art exists, provide a simple structure, design benefit, rationally distributed can carry out centering operation to the bent axle automatically when pressing from both sides tightly, still has simultaneously and judges through the gas detection whether press from both sides the high accuracy three-jaw centering mechanism that whether tightly targets in place function band gap detected.

The technical solution of the utility model is that: the utility model provides a take air gap to detect high accuracy three-jaw centering mechanism which characterized in that: the centering mechanism comprises a shell 1, a driving shaft 2 is connected in the shell 1 in a sliding manner, a piston 3 is connected on the driving shaft 2, the piston 3 is positioned in a hydraulic cavity arranged in the shell 1, the end part of the driving shaft 2 is conical, three expansion pins 5 are connected on the driving shaft 2 in a sliding manner through an inclined dovetail groove mechanism 4, the axis of each expansion pin 5 is vertical to the axis of the driving shaft 2, the expansion pins 5 are connected in the shell 1 in a sliding manner, the included angle between a dovetail groove in the inclined dovetail groove mechanism 4 and the horizontal plane is 4-8 degrees,

each expansion pin 5 is internally provided with an airtight detection gas path 6, the airtight detection gas path 6 is parallel to the axis of the expansion pin 5, the expansion pin 5 is internally provided with a first connecting gas path 7, the first connecting air passage 7 is communicated with the air tightness detection air passage 6 and is vertical to the air tightness detection air passage, a transition sleeve 8 is arranged in the shell 1, a second connecting air passage 9 is arranged in the transition sleeve 8, one side of the transition sleeve 8 facing the direction of the expansion pin 5 is provided with a transition long groove 10, the first connecting air path 7 and the second connecting air path 9 are both communicated with the transition long groove 10, sealing rings 11 are arranged on the outer side and the inner side of the transition long groove 10, an air passage 12 is arranged in the side wall of the shell 1, the tail end of the gas path 12 is connected with an annular groove 13 formed in the transition sleeve 8, the annular groove 13 and the transition long groove 10 are respectively located on two sides of the transition sleeve 8, and all the second connecting gas paths 9 are connected with the annular groove 13.

Compared with the prior art, the utility model, have following advantage:

the high-precision three-jaw centering mechanism with the air gap detection in the structural form has the advantages of simple structure, ingenious design and reasonable layout, and is designed to be a special structure aiming at various problems of the traditional clamp and the centering mechanism in the working process. The axial movement of the driving shaft is converted into the radial movement of the three expansion pins by utilizing the dovetail grooves which are distributed in an inclined manner, the internal support type clamping operation of the cylindrical workpiece is realized through the action of the three expansion pins, and the movement speeds and the amplitudes of the three expansion pins are consistent, so that the mechanism can automatically center the cylindrical workpiece while clamping, and the cost and the workload of additionally arranging a centering mechanism are saved; the inclined dovetail groove is designed to be a special inclination angle, and has a self-locking function, so that the automatic reverse movement of the expansion pin can be effectively prevented, and the reliability of the mechanism is ensured; meanwhile, a detection gas circuit is arranged in the expansion pins, and whether all the expansion pins are in close contact with the inner wall of the workpiece can be known through a gas pressure sensor arranged on the gas circuit, so that a user is helped to judge whether the workpiece is in a stable clamped state at present, and accidents are prevented. In conclusion, the centering mechanism has multiple advantages, is suitable for popularization and application in the field, and has a very wide market prospect.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

Fig. 2 is an enlarged view of a portion a in fig. 1.

Detailed Description

The following description will explain embodiments of the present invention with reference to the drawings. As shown in fig. 1 and 2: a high-precision three-jaw centering mechanism with air gap detection comprises a shell 1, wherein a driving shaft 2 is connected in the shell 1 in a sliding mode, a piston 3 is connected on the driving shaft 2, the piston 3 is located in a hydraulic cavity arranged in the shell 1, the end portion of the driving shaft 2 is in a conical shape, three expansion pins 5 are connected onto the driving shaft 2 in a sliding mode through an inclined dovetail groove mechanism 4, the axis of each expansion pin 5 is perpendicular to the axis of the driving shaft 2, the expansion pins 5 are connected into the shell 1 in a sliding mode, the included angle between a dovetail groove in the inclined dovetail groove mechanism 4 and the horizontal plane is 4-8 degrees,

The utility model discloses take high accuracy three-jaw centering mechanism of air gap detection's working process as follows: when a cylindrical workpiece needs to be clamped and centered, firstly, the end part of the device is deeply inserted into the workpiece, then a hydraulic system is started, hydraulic oil is filled into a hydraulic cavity, a driving piston 3 drives a driving shaft 2 to move, so that expansion pins 5 connected with the driving shaft 2 in a sliding mode through an inclined dovetail groove mechanism 4 move along the radial direction of the driving shaft 2, the three expansion pins 5 synchronously move simultaneously, the end parts of the three expansion pins are in contact with the inner wall of the cylindrical workpiece, and the cylindrical workpiece can be automatically centered in the process because the three expansion pins 5 are uniformly distributed in the circumferential direction;

after the workpiece is clamped, because the included angle between the dovetail groove in the inclined dovetail groove mechanism 4 and the horizontal plane is 4-8 degrees, the angle can effectively prevent the expanding pin 5 from automatically retracting, thereby ensuring the reliability of clamping;

meanwhile, after the workpiece is clamped, the control system controls the air source to work, high-pressure air is pumped into the air path 12, the air enters the annular groove 13, then simultaneously enters the three second connecting air paths 9, enters the first connecting air path 7 through the long transition groove 10 and finally enters the air tightness detection air path 6, if the end part of the expansion pin 5 is in good close contact with the inner wall of the workpiece, no air can be leaked from the connecting surface of the expansion pin and the inner wall of the workpiece, the air pressure in the air path is constant at the moment, otherwise, if the air pressure in the air path is not consistent with the theoretical value (or is changed violently), the control system indicates that good contact is not achieved between the expansion pin 5 and the inner wall of the workpiece at the moment, and sends out warning information to remind an operator at the; because the first connecting air passage 7 and the second connecting air passage 9 are connected through the relatively long transitional long groove 10, even if the extending positions of the expansion pins 5 are different when the expansion pins clamp workpieces of different specifications, all the air passages of the device can still be normally communicated.

Claims

1. The utility model provides a take air gap to detect high accuracy three-jaw centering mechanism which characterized in that: centering mechanism include casing (1), sliding connection has drive shaft (2) in casing (1), be connected with piston (3) on drive shaft (2), piston (3) are arranged in seting up the hydraulic pressure chamber in casing (1), and the tip of drive shaft (2) is the taper, has three round pin (5) that rise through oblique dovetail mechanism (4) sliding connection on it, the axis that rises round pin (5) is mutually perpendicular with the axis of drive shaft (2), rises round pin (5) sliding connection simultaneously in casing (1), the contained angle between dovetail and the horizontal plane in the oblique dovetail mechanism (4) is 4-8,

each expansion pin (5) is internally provided with an airtight detection gas path (6), the airtight detection gas path (6) is parallel to the axis of each expansion pin (5), each expansion pin (5) is internally provided with a first connection gas path (7), the first connection gas path (7) is communicated with the airtight detection gas path (6) and is perpendicular to the airtight detection gas path, a transition sleeve (8) is arranged in the shell (1), a second connection gas path (9) is arranged in the transition sleeve (8), one side of the transition sleeve (8) facing the direction of each expansion pin (5) is provided with a transition long groove (10), the first connection gas path (7) and the second connection gas path (9) are both communicated with the transition long groove (10), the outer side and the inner side of the transition long groove (10) are both provided with sealing rings (11), a gas path (12) is arranged in the side wall of the shell (1), and the tail end of the gas path (12) is connected with an annular groove (13) formed in the transition sleeve (, the annular groove (13) and the transition long groove (10) are respectively positioned at two sides of the transition sleeve (8), and all the second connecting air passages (9) are connected with the annular groove (13).