CN214292625U - Special clamp for online detection of part clamping concentricity - Google Patents

Abstract

The utility model provides a special fixture of part clamping concentricity on-line measuring, its main points lie in, the ejector pin of detection usefulness is fixed in on the mesa of processing equipment by special fixture, special fixture comprises the fixed bolster, the ejector pin, flexible slip table cylinder, side closing device, the air supply, control system, flexible slip table cylinder is fixed in on the fixed bolster, the top is fixed with L type slip table, flexible slip table cylinder top is met with the measuring tool dead lever through the horizontal long limit of slip table, the ejector pin is fixed in the lateral surface of the perpendicular minor face of slip table, the piston rod of flexible slip table cylinder meets with the medial surface of perpendicular minor face, the measuring terminal surface and the ejector pin surface contact of measuring tool, measuring tool and ejector pin are under the effect of flexible slip table cylinder, synchronous axial displacement, side closing device acts on the measuring tool dead lever top, during operation compress tightly the measuring tool dead lever downwards. The advantages are that: clamping detection is not affected by the surface of the part, whether the clamping of the part meets the coaxiality requirement can be measured, and the product quality and the qualified rate of the product can be improved.

Description

Special clamp for online detection of part clamping concentricity

Technical Field

The utility model belongs to machining's detection method especially belongs to concentricity on-line measuring method and measuring device.

Background

The heat treatment is easy to cause part deformation, especially for fine rods (generally, rods with a length-diameter ratio greater than 5), the processing method of the parts is generally to perform rough processing, leave a finishing allowance, perform heat treatment, and perform final finishing to ensure the design size of the rod, such as the coaxiality of an inner circle and an outer circle. When the coaxiality requirement exists between the processing inner hole and the excircle, particularly the diameter of the processing inner hole is less than 5mm (all the units of the size of the application are millimeters), the clamping is difficult to meet the requirement. The current fine machining of the parts after heat treatment is to process an outer circular surface by matching two end surface thimble holes (or chamfer surfaces of an inner hole) with thimbles and the like, after the outer circle is processed, re-clamping is carried out to process the inner hole, at the moment, the outer circular surface at one end is matched with a chuck (a clamp) of machining equipment, the runout of the outer circle is detected by a dial indicator, whether a clamping center of the part is coaxial with the rotation axis of the equipment is judged, whether the clamping meets the requirement of coaxiality is detected, if the clamping does not meet the requirement, the chuck of the machining equipment is loosened to adjust, clamp, detect and readjust … … repeatedly, when the structure of the outer circular surface is not a full circle, a groove or a hole is formed, a measuring head of the dial indicator generates vibration when contacting the groove or the hole, the measuring head can be restabilized for a long time, and the detection cannot be completed. The design requirement diagram of the chuck of the electric sander shown in fig. 1 and 2 (the size and the processing requirement irrelevant to the present invention are removed for simplification and emphasis due to the multiple and complicated processing sizes), because the head of the chuck is opened with three vertical grooves downwards, the chuck has certain elasticity on the circumference for holding grinding tools such as grinding rods, which is generally called as a three-petal spring chuck 7, and the outer circle is

And has the coaxiality requirement that the roundness is required to reach 0.002, the coaxiality is 0.003 and the inner hole phi 3 is the same₀ ^+0.01The roundness of the outer surface of the cylindrical member is required to be 0.002, the coaxiality with the outer circumferential surface is required to be 0.003mm, the processing method is that a fine processing allowance is left during rough processing, heat treatment is carried out after rough processing, the outer surface is finely processed after heat treatment, and a grinding machine is usedWhen an inner hole is finely machined, a grinding machine spindle clamp is used for clamping an excircle at the tail part, the inner hole is machined, the length of a vertical groove is 14.5mm, the total length is 32mm, the aperture is 1mm, the length for clamping and measuring is only 17mm, the diameter of a measuring head of a dial gauge is 8mm, the diameter of a dial plate is 50-60mm, necessary clamping positions are deducted, the detection positions which are not influenced by the vertical groove are almost not available, clamping detection cannot be completed, the machining of the three-petal spring chuck cannot meet the design requirements, and the product quality cannot be guaranteed.

Therefore, the existing three-petal spring chuck machining can only place the machining of three vertical grooves in the final process, the HRC reaches 48-52 after heat treatment, the grooving needs to use finish machining equipment (such as a finish grinding machine and the like), the machining amount is large, the production cost is high, meanwhile, the machining amount is large, the machining heat is high, parts are easy to generate thermal deformation, the product quality is influenced, the product qualification rate is low, and the machining cost is high and the waste is serious due to the fact that the final machining process causes the product to be unqualified.

SUMMERY OF THE UTILITY MODEL

The utility model aims to overcome present thermal treatment back, outer disc unsmooth, slotted or the little part in hole, when the finish machining hole, can't detect the defect that the clamping reached the axiality requirement, provide a no matter how unevenness of part surface structure, can both measure the special fixture of the part clamping concentricity on-line measuring that the clamping whether reached the axiality requirement.

The technical scheme adopted by the utility model is a special fixture for online detection of part clamping concentricity, which is characterized in that a mandril for detection is fixed on the table top of machining equipment by the special fixture, the special fixture comprises a fixed support, the mandril, a telescopic slipway cylinder, a side pressing device, an air source and a control system, the telescopic slipway cylinder is connected with the air source, the telescopic slipway cylinder and the side pressing device are respectively and electrically connected with the control system, the bottom of the fixed support is provided with a fixed hole connected with the table top of the machining equipment and fixed with the table top of the machining equipment by a fixing piece, the telescopic slipway cylinder is fixed on the fixed support, the top of the telescopic slipway cylinder is fixed with a slipway which is L-shaped, the top of the telescopic slipway cylinder is connected with a fixed rod of a measuring tool by a horizontal long edge of the slipway, the mandril is fixed on the outer side surface of a vertical short edge of the slipway, the piston rod of the telescopic sliding table cylinder is connected with the inner side face perpendicular to the short side, the measuring tool is fixed at the cantilever end of the measuring tool fixing rod, the measuring end face of the measuring tool is in contact with the outer surface of the ejector rod, the measuring tool and the ejector rod move axially synchronously under the action of the telescopic sliding table cylinder, the side face pressing device acts above the measuring tool fixing rod, and the measuring tool fixing rod is pressed downwards during working.

The special fixture is arranged on the table board of the machining equipment, the ejector rod connected with the central hole of the part is connected through the outer part, namely, the central line of the central hole of the part is prolonged, the measuring space is enlarged, the installation and fixation of the measuring tool are not limited by the space, the clamping detection is not influenced by the unevenness of the surface of the part, the ejector rod of the special fixture and the measuring tool move synchronously, namely, after the special fixture is installed, the measuring surface of the measuring tool is unchanged, the ejector rod does not rotate after the ejector pin of the ejector rod is connected with the central hole of the part to be machined, the ejector rod jumps along with the rotation of the part when the central line of the part is not superposed with the rotation center of the machining equipment, the center of the ejector rod is driven to move up and down, the measuring value of the measuring tool changes, and the change of the data measured by the ejector rod shows the non-concentricity of the part and the rotation center of the machining equipment.

The thimble at the head of the thimble is matched with the central hole of the part, and the matching means that the taper of the thimble is the same as that of the positioning chamfer surface of the central hole of the part.

The ejector rod is made of tungsten steel, the ejector rod is fixed on the outer side face of the vertical short edge of the sliding table, namely the spring seat is fixed with the vertical short edge of the sliding table, the buffer spring is fixed in the spring seat, and the ejector rod is fixed in the buffer spring and in interference fit with the inner surface of the buffer spring. And a buffer spring is added, so that the ejector rod has certain self-adaptive capacity in the radial direction.

The side pressing device is a double-column clamping cylinder, is fixed on the side of the fixed support and is connected with an air source, and the lower pressure of the side pressing device is more than 35 kg. Because the extension length of the ejector rod is matched, the fixed end of the measuring tool becomes a cantilever beam, the weight of the cantilever of the measuring tool and the fixed rod of the measuring tool does not exceed 1kg, in order to ensure the stability of the measuring tool, the downward pressure is particularly used to be more than 35kg, and the double-column clamping cylinder is pressed at the rear end of the fixed rod of the measuring tool, so that the measuring tool, the fixed rod of the measuring tool and the cylinder of the telescopic sliding table are fixed into a stable whole.

The utility model has the advantages that: the special fixture is arranged on the table board of the machining equipment, the ejector rod connected with the central hole of the part is connected through the outer part, namely, the central line of the central hole of the part is prolonged, the measuring space is enlarged, the installation and fixation of the measuring tool are not limited by the space, the clamping detection is not influenced by the unevenness of the part, the ejector rod of the special fixture and the measuring tool move synchronously, namely, after the special fixture is installed, the measuring surface of the measuring tool is unchanged, the ejector rod does not rotate after the ejector pin of the ejector rod is connected with the central hole of the part to be machined, the ejector rod jumps along with the rotation of the part when the central line of the part is not superposed with the rotation center of the machining equipment, the center of the ejector rod is driven to move up and down, the measuring value of the measuring tool changes, and the change of the data measured by the ejector rod shows the non-concentricity of the part and the rotation center of the machining equipment. The clamp is applied to the three-petal spring chuck of the electric grinding machine, the processing procedure of the three-petal spring chuck can be changed, three vertical grooves are partially processed during rough processing, the finish processing amount is reduced, the production cost is reduced, and the qualification rate of products is improved.

Drawings

FIG. 1 is a design drawing of a three-petal spring collet

FIG. 2 is a cross-sectional view of FIG. 1

FIG. 3 is a schematic structural diagram of the present invention

FIG. 4 is a schematic diagram of the mechanism of the rough machined three-petal spring chuck of the present invention

FIG. 5 is a cross-sectional view of FIG. 4

FIG. 6 is a side view of FIG. 4

Wherein: the device comprises a fixing support 1, a push rod 2, a buffer spring 21, a telescopic sliding table cylinder 3, a sliding table 31, a side pressing device 4, a measuring tool fixing rod 5, a measuring tool 6, a measuring end face 61, a three-petal spring chuck 7, three vertical grooves 71, a hole 72, a non-cutting part 73, a top clamping face 74, a head taper section 75 and a fixture of a grinding machine rotating main shaft 9.

Detailed Description

The embodiments illustrated herein will enable those skilled in the art to more fully understand the present invention, without limiting it in any way, when the present invention is described in detail below with reference to the accompanying drawings.

As shown in fig. 3, a special fixture of part clamping concentricity on-line measuring detects on the ejector pin is fixed in the mesa of machining equipment by special fixture, special fixture by fixed bolster 1, ejector pin 2, flexible slip table cylinder 3, side closing device 4, air supply, control system constitute, side closing device is double-column die clamping cylinder, flexible slip table cylinder meet with the air supply respectively, the pressure of air supply is between 0.4-1Mpa, flexible slip table cylinder and side closing device are connected with the control system electricity respectively, flexible slip table cylinder and side closing device press from both sides tight course and do: after the telescopic sliding table cylinder extends in place, the side face pressing device presses downwards; the loosening process is as follows: the side pressing device is firstly released, and the telescopic sliding table cylinder is then released. The two cylinders are linked through a time delay switch, and only one control switch is used for controlling the two cylinders. The ejector pin is made of tungsten steel, the strength is high, the wear resistance is good, the bottom of the fixed support is provided with a fixed hole which is fixed with the table top of the machining equipment through a fixing piece, the telescopic sliding table cylinder 3 is fixed on the fixed support, the top of the telescopic sliding table cylinder is fixed with a sliding table 31 which is L-shaped, the top of the telescopic sliding table cylinder is connected with a measuring tool fixed rod 5 through the horizontal long edge of the sliding table, the ejector pin at the head of the ejector pin is matched with the central hole of a part, namely, the taper of the ejector pin is the same as the taper of the positioning chamfer surface of the central hole of the part, the taper of the ejector pin of the utility model is 60 degrees, the ejector pin is fixed on the outer side surface of the vertical short edge of the sliding table, the spring seat 22 is fixed with the vertical short edge of the sliding table, the buffer spring 21 is fixed in the spring seat, the excircle of the buffer spring is in interference fit with the inner hole of the spring seat (viscose can be added between the two to ensure the two to be firmly connected), ejector pin 2 is for whole cylindricality, comprises the different structure of three-section, and the head is sharp conical thimble, and the centre is the cylinder pole, and the afterbody also is the cylinder pole, and the excircle diameter of afterbody is less than the diameter of middle cylinder pole, and the step face between the two is the contact surface of buffer spring terminal surface, and the cylinder pole of ejector pin afterbody is fixed in buffer spring, is interference fit (still can increase the viscose between the two in order to guarantee the two firmly to be connected) with the buffer spring internal surface, and buffer spring's surface is the same with the diameter of ejector pin interlude. The piston rod of the telescopic sliding table cylinder is connected with the inner side surface of the vertical short edge of the sliding table, the sliding table is pushed to move through the piston rod, the measuring tool is fixed at the cantilever end of the fixing rod of the measuring tool, the measuring end surface of the measuring tool is in contact with the outer surface of the ejector rod, the measuring tool and the ejector rod move axially synchronously under the action of the telescopic sliding table cylinder, the side pressing device acts above the fixing rod of the measuring tool, and the fixing rod 5 of the measuring tool is pressed downwards during operation. The side pressing device is fixed on the side of the fixed support, and the downward pressure of the side pressing device is greater than 35 kg. Because the extension length of the ejector rod is matched, the fixed end of the measuring tool becomes a cantilever beam, the weight of the cantilever of the measuring tool and the fixed rod of the measuring tool does not exceed 1kg, and in order to ensure the stability of the measuring tool, a double-column clamping cylinder with the lower pressure larger than 35kg is pressed at the rear end of the fixed rod of the measuring tool, so that the measuring tool, the fixed rod of the measuring tool and the cylinder of the telescopic sliding table are fixed into a stable whole.

The method is applied to the processing of the three-petal spring chuck, so that the existing processing procedure of the three-petal spring chuck can be improved. The method comprises the following specific steps:

as shown in fig. 1-6, a method for processing a three-petal reed chuck of an electric grinding machine shown in fig. 1 and 2 by using the online detection method for the part clamping concentricity comprises the following steps: a) rough machining of a machine tool, namely rough machining of the outer surface and the inner hole (reserving a finish machining allowance), and a machining method of the three vertical grooves 71: the method comprises the steps of firstly processing a hole 72 (a hole with the diameter of 1.00 in the drawing) at the root part of three vertical grooves, drilling a through hole, then slotting the head part of the three-petal spring chuck from the hole, keeping the head part not to be cut off, keeping the length of 2-6mm from the surface of the head part to the inside in the axial direction, slotting the inner wall from the outer surface to the inner wall for the part which is not to be cut off, and keeping the thickness of the inner wall not to be cut off by 0.3-0.5 mm. Theoretically, the axial length of the uncut portion 73 may be equal to the axial length of the clamping surface 74 at the top end of the inner hole of the head of the three-lobed spring collet (i.e., the axial length of the 60 ° chamfer at the top end of the inner hole of the head of the three-lobed spring collet), and in consideration of the strength, as shown in fig. 5, the thickness of the inner wall is generally selected to be 5mm

Or the head part taper section 75 is axially arranged, the outer surface is internally grooved, the inner wall thickness is kept to be 0.3-0.5mm without cutting off, and the head part taper section is provided with oneA complete clamping surface, namely, three vertical grooves of the three-petal spring chuck are completely grooved (as shown in the lower part of figure 5 at the position of a mark 71), and the head part has a section which is not cut when being seen from the inner wall, and the clamping surface has a complete clamping surface (a non-cutting part 73) which can be used for tightly supporting the three-petal spring chuck by a mandril of a special clamp (if the three vertical grooves are completely cut, the three-petal spring chuck has elasticity on the circumference and cannot clamp the mandril);

b) heat treatment, HRC reaches 48-52;

c) processing the outer circular surface after heat treatment, and finely processing by a grinding machine: the thimble is used for propping against the three-petal spring chuck at the two ends of the part and finely grinding the outer surface;

d) finish machining an inner hole: the outer surface of the fine ground tail of the three-petal spring chuck 7 is arranged in a clamp 9 of a rotating main shaft of an internal grinding grinder, the taper angle of a thimble of a special clamp ejector rod is 60 degrees, the taper angle is matched with a clamping surface 74 (a 60-degree chamfer angle at the top end of a head inner hole) at the top end of the three-petal spring chuck in figure 4, the front end of the three-petal spring chuck is propped against a part central hole by the thimble at the head of the ejector rod, an air inlet valve of an air passage is opened, a telescopic sliding table cylinder is pushed forwards, the thimble at the head of the ejector rod is propped against the part central hole, a double-column clamping cylinder of a side surface pressing device downwards presses a measuring tool fixing rod by linkage of a control system, the downward pressure is 50kg, the special clamp and the measuring tool (dial indicator) 6 are stably integrated at the moment, the rotating internal grinding rotating main shaft (clamp) is rotated for more than one circle, at the moment, a measuring end surface 61 of the measuring rod of the dial indicator is contacted with the outer surface of the ejector rod, and the coaxiality of the rotating main shaft of the ejector rod and the equipment is detected, the coaxial installation measurement of the inner hole and the rotating main shaft is realized, the measurement result does not meet the requirement, the ejector rod is loosened, the clamping of the rotating main shaft on the three-petal spring chuck is readjusted, the measurement is carried out again until the installation is qualified, the ejector rod is withdrawn, the cutter enters the processing inner hole, and the size is phi 3_-0.08Is processed to phi 3₀ ^+0.01。

e) Cutting the head of the three-petal spring chuck: the head of the three vertical slots is cut, and when the vertical slot at the head of the three-petal spring chuck is cut, the head is cut inwards.

The rest of the parts which are not described are the same as the prior art.

Above embodiment only is for explaining the utility model discloses a technical thought can not be injectd with this the utility model discloses a protection scope, all according to the utility model provides a technical thought, any improvement of doing on technical scheme basis and equal replacement all fall into within the protection scope of the utility model.

Claims (5)

1. A special fixture for online detection of part clamping concentricity is characterized in that a mandril for detection is fixed on a table top of machining equipment by the special fixture, the special fixture comprises a fixed support, the mandril, a telescopic sliding table cylinder, a side pressing device, an air source and a control system, the telescopic sliding table cylinder is connected with the air source, the telescopic sliding table cylinder and the side pressing device are respectively electrically connected with the control system, the bottom of the fixed support is provided with a fixed hole which is connected with the table top of the machining equipment and is fixed with the table top of the machining equipment by a fixing part, the telescopic sliding table cylinder is fixed on the fixed support, the top of the telescopic sliding table cylinder is fixed with an L-shaped sliding table, the top of the telescopic sliding table cylinder is connected with a measuring tool fixing rod by a horizontal long edge of the sliding table, the mandril is fixed on the outer side surface of a vertical short edge of the sliding table, and a piston rod of the telescopic sliding table cylinder is connected with the inner side surface of the vertical short edge, the measuring tool is fixed on the cantilever end of the measuring tool fixing rod, the measuring end surface of the measuring tool is in contact with the outer surface of the ejector rod, the measuring tool and the ejector rod synchronously and axially move under the action of the telescopic sliding table cylinder, the side face pressing device acts above the measuring tool fixing rod, and the measuring tool fixing rod is pressed downwards during working.

2. The special fixture for online detection of clamping concentricity of parts as claimed in claim 1, wherein a thimble at the head of the thimble is matched with a central hole of the part.

3. The special fixture for online detection of the clamping concentricity of the part as claimed in claim 2, wherein the matching means that the taper of the thimble is the same as the taper of the positioning chamfer surface of the central hole of the part.

4. The special fixture for online detection of part clamping concentricity according to claim 1, wherein the ejector rod is made of tungsten steel, the ejector rod is fixed on the outer side surface of the vertical short edge of the sliding table, namely the spring seat is fixed with the vertical short edge of the sliding table, the buffer spring is fixed in the spring seat, and the ejector rod is fixed in the buffer spring and is in interference fit with the inner surface of the buffer spring.

5. The special fixture for the online detection of the clamping concentricity of the part as claimed in claim 1, wherein the side pressing device is a double-column clamping cylinder, is fixed on the side surface of the fixed bracket and is connected with an air source, and the lower pressure of the side pressing device is more than 35 kg.

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