Auxiliary fixture for finishing the outer cylindrical surface of a ring

Abstract

The application belongs to the technical field of clamps, and particularly relates to an auxiliary clamp for finish machining of the outer circular surface of a ring-shaped part, which comprises a base body and a clamp body fixed at the front end of the base body, the clamp body comprises a large-diameter section and a small-diameter section, a step is formed at the joint of the large-diameter section and the small-diameter section, and a positioning sleeve is sleeved on the small-diameter section; a strutting part is connected to the front end of the small-diameter section, an expansion sleeve is sleeved on the strutting part, the surfaces in contact with each other between the expansion sleeve and the strutting part are all conical surfaces, the expansion sleeve is matched with a mandrel; an adjusting groove is arranged on the outer wall of the small-diameter section, the adjusting groove has a hemispherical structure or a conical structure which gradually narrows from the opening to the bottom, the positioning sleeve is provided with a first adjusting hole, the center line of the adjusting groove is closer to the step than the center line of the first adjusting hole, and the first adjusting hole is threadedly matched with a first adjusting bolt. The application has the advantages that the flatness of the tooling is adjusted to ensure the machining precision of the outer circular surface of the ring-shaped part.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of clamps, and particularly relates to an auxiliary clamp for finish machining of an outer circular surface of a ring-shaped part. BACKGROUND

[0002] Some ring-shaped parts need to use an auxiliary clamp for finish machining of an outer circular surface. The auxiliary clamp is usually an inner supporting clamp. The inner supporting clamp is expanded from inside to outside to expand the inner hole of the ring-shaped part to clamp the ring-shaped part. The auxiliary clamp usually needs to be fixed on a machine tool. The auxiliary clamp is usually provided with a positioning sleeve to position the position of the ring-shaped part, so that the position of the ring-shaped part does not deviate during machining. For example, when the outer circular surface of the ring-shaped part needs to be gear hobbed or turned, the flatness of the ring-shaped part needs to be ensured to be good, so that the machining precision of the outer circular surface of the ring-shaped part is good.

[0003] For example, a lathe inner supporting limiting clamp is disclosed in Chinese Patent No. 202221042184.4, which comprises a main body for fixed connection with a lathe; further comprising a pull rod, a pull pin, a positioning piece and a product fixing piece, the pull rod is arranged on one side of the main body close to the lathe, the positioning piece is arranged on the side of the main body away from the lathe, and the product fixing piece is arranged on the side of the positioning piece away from the main body.

[0004] The above scheme positions the ring-shaped part to be machined by the positioning piece. The positioning piece is fixed with the main body by screws. The main body is fixed with the lathe together, but it is difficult to ensure the flatness of the positioning piece after the main body is fixed with the lathe together. And different positioning pieces need to be used when different ring-shaped parts are machined, so the positioning piece needs to be replaced. After replacement, the end face run-out value of the positioning piece needs to be detected by a micrometer to ensure the flatness of the positioning piece. The above scheme is difficult to adjust the flatness of the positioning piece. When the flatness of the positioning piece does not meet the requirements, the ring-shaped part will deviate during positioning, which cannot ensure the flatness of the ring-shaped part, resulting in poor precision of the outer circular surface of the ring-shaped part during machining. SUMMARY

[0005] The purpose of the application is to provide an auxiliary clamp for finish machining of an outer circular surface of a ring-shaped part, which adjusts the flatness of the tooling to ensure the machining precision of the outer circular surface of the ring-shaped part.

[0006] To achieve the above object, the application adopts the following technical scheme: an auxiliary fixture for finishing the outer cylindrical surface of a ring-shaped workpiece, comprising a base body for being fixed to a machine tool and a fixture body for positioning the ring-shaped workpiece, the fixture body being fixed to the front end of the base body, the fixture body comprising a large-diameter section close to the base body and a small-diameter section away from the base body, a step being formed at the connection between the large-diameter section and the small-diameter section, a positioning sleeve being sleeved on the small-diameter section, one end face of the positioning sleeve being in contact with the end face of the step, and the other end face of the positioning sleeve being used for being in contact with the end face of the ring-shaped workpiece; a strutting part being connected to the front end of the small-diameter section, an expansion sleeve being sleeved on the strutting part for expanding the inner hole of the ring-shaped workpiece, the surfaces in contact with each other between the expansion sleeve and the strutting part being conical surfaces, the expansion sleeve being matched with a mandrel for realizing the axial movement of the expansion sleeve; at least three radially extending adjusting grooves being uniformly and circumferentially arranged on the outer wall of the small-diameter section, the adjusting grooves being in a hemispherical structure or a conical structure gradually narrowing from the opening to the bottom, the positioning sleeve being provided with first adjusting holes radially penetrating one by one corresponding to the adjusting grooves, the adjusting grooves and the first adjusting holes being non-concentrically arranged, the center line of the adjusting grooves being closer to the step than the center line of the first adjusting holes, the first adjusting holes being threadedly matched with first adjusting bolts; when the first adjusting bolts are screwed into the first adjusting holes and are in contact with the adjusting grooves, the positioning sleeve has a tendency to move towards the step so that the end face of the positioning sleeve is tightly attached to the end face of the step.

[0007] Among them, the mandrel for realizing the movement of the expansion sleeve can be a push-pull type mandrel or a threaded screw type mandrel.

[0008] Among them, when the first adjusting bolts are threadedly matched with the first adjusting holes, the heads of the first adjusting bolts will be in contact with the groove walls of the adjusting grooves, and when the first adjusting bolts continue to be screwed, the center line of the first adjusting holes will gradually approach the center line of the adjusting grooves due to the gradually narrowing width of the adjusting grooves from the outside to the inside, so that the positioning sleeve has a downward moving force, thereby making the lower end face of the positioning sleeve tightly attached to the end face of the step.

[0009] Among them, the device can be in a vertical or horizontal position, and during the processing of the ring-shaped workpiece, a center will be in contact with the ring-shaped workpiece, so that the ring-shaped workpiece is tightly attached to the end face of the positioning sleeve.

[0010] The cooperation of the adjusting grooves, the first adjusting holes and the first adjusting bolts makes the positioning sleeve have a tendency to move towards the step face when it is fixed, and when the flatness of the positioning sleeve does not meet the requirements, the first adjusting bolts can be screwed to finely adjust the flatness of the ring-shaped workpiece. At the same time, the positioning sleeve can be tightly attached to the step face, and when the flatness of the step face meets the requirements, the flatness of the positioning sleeve can be further ensured, so that the positioning of the ring-shaped workpiece by the positioning sleeve is more accurate. Compared with the comparative file, the ring-shaped workpiece is more convenient to disassemble, and the screwdriver is radially screwed without contacting the internal strutting chuck.

[0011] Preferably, the base body is provided with a matching hole opening to the large-diameter section side, the bottom of the large-diameter section is provided with a matching protrusion extending into the matching hole, and the outer wall of the matching protrusion is in contact with the inner wall of the matching hole; the base body is provided with at least three second adjustment holes uniformly spaced in the circumferential direction and radially penetrating, and the second adjustment holes are threadedly matched with second adjustment bolts, the end portions of the second adjustment bolts being in contact with the outer wall of the matching protrusion.

[0012] A step is formed between the large-diameter section and the thin section, and the end face of the step is actually the end face of the large-diameter section. In order to ensure the flatness of the positioning sleeve, the flatness of the end face of the step also needs to be ensured. The second adjustment bolts are screwed against the matching protrusion, thereby achieving adjustment of the levelness of the large-diameter section and adjustment of the flatness of the end face of the step.

[0013] Preferably, the inner edge of the front end of the positioning sleeve is provided with a plurality of axially opening avoidance grooves, the depth of the avoidance grooves gradually increases from the radial outer side to the radial inner side, and the avoidance grooves are in communication with the inner hole of the positioning sleeve.

[0014] The avoidance grooves can reduce the contact area between the positioning sleeve and the annular workpiece, thereby increasing the positioning accuracy. In addition, iron filings are generated during machining of the annular workpiece. The depth of the avoidance grooves gradually increases from the outside to the inside, the avoidance grooves are in communication with the inner hole of the positioning sleeve, which facilitates the operator to drain the cooling water and clean the iron filings. At the same time, the avoidance grooves are only provided at the inner edge, and the end face at the outer edge needs to be in contact with the dial gauge, thereby detecting the flatness of the positioning sleeve.

[0015] Preferably, the clamp body and the strutting portion are both provided with a first positioning hole axially extending and used for positioning a mandrel, the outer wall of the mandrel being in contact with the inner wall of the first positioning hole; the small-diameter section is provided with at least three first limiting holes uniformly spaced in the circumferential direction and radially penetrating, the first limiting holes being in communication with the first positioning hole, the first limiting holes being threadedly matched with first limiting members, and the end portions of the first limiting members being in contact with the outer wall of the mandrel.

[0016] The mandrel needs to move axially to realize movement of the expansion sleeve and cooperate with the strutting portion to realize expansion of the expansion sleeve on the annular workpiece. The mandrel and the first positioning hole are in clearance fit, and there is a limiting structure between the expansion sleeve and the mandrel. The concentricity of the mandrel affects the concentricity of the expansion sleeve, so the first limiting member is arranged to adjust the radial position of the mandrel, so that the run-out value of the mandrel meets the standard range and the concentricity is good. Thus, the expansion sleeve is more accurate when expanding the annular workpiece.

[0017] Preferably, the positioning sleeve is provided with a through hole penetrating in the radial direction and corresponding to the first limiting hole one by one, and the outer wall of the mandrel is provided with a first long hole opening laterally and extending axially, and the first limiting member passes through the through hole, the first limiting hole and the first long hole in sequence from outside to inside to limit the circumferential rotation of the mandrel.

[0018] The first limiting member is usually a bolt, and the first limiting member passes through the through hole, the first limiting hole and the first long hole in sequence from outside to inside, so as to limit the circumferential position of the mandrel and the circumferential position of the positioning sleeve, so that the mandrel and the positioning sleeve cannot rotate, and the stability of the device is ensured. When the first limiting member is a bolt, the through hole is used to accommodate the head of the bolt. "From outside to inside" refers to from the radial outside to the radial inside.

[0019] Preferably, the large-diameter section and the base body are both provided with a second positioning hole extending axially, the second positioning hole is coaxially arranged and communicated with the matching hole, the inner diameter of the matching hole is larger than that of the second positioning hole, the outer wall of the mandrel is in contact with the inner wall of the second positioning hole, and the part of the mandrel located in the matching hole is provided with a first limiting protrusion extending radially outward to limit the axial movement stroke of the mandrel.

[0020] The first limiting protrusion is located in the matching hole, and the inner diameter of the matching hole is larger than that of the second positioning hole, so that when the mandrel moves axially, the first limiting protrusion cannot enter the second positioning hole, thereby limiting the stroke of the axial movement of the mandrel, avoiding excessive movement of the mandrel, and preventing the expansion sleeve from being stuck between the expansion sleeve and the expansion part or the expansion sleeve from being separated from the expansion part.

[0021] Preferably, the front end of the mandrel is provided with a limiting groove opening radially outward, and the front end of the expansion sleeve is provided with a second limiting protrusion extending radially inward and extending into the limiting groove.

[0022] The cooperation of the limiting groove and the second limiting protrusion enables the mandrel and the expansion sleeve to have a limiting structure, thereby realizing the synchronous movement of the expansion sleeve and the mandrel, and facilitating the resetting of the expansion sleeve after the mandrel is reset.

[0023] Preferably, the front end face of the second limiting protrusion in the axial direction is a bevel, the width of the second limiting protrusion in the axial direction gradually decreases from the radial outside to the radial inside, the mandrel is provided with a third limiting protrusion extending radially outward, the third limiting protrusion is located at the rear end of the limiting groove in the axial direction, the rear end face of the third limiting protrusion in the axial direction is a bevel, and the width of the third limiting protrusion in the axial direction gradually increases from the radial outside to the radial inside.

[0024] The front end of the second limiting protrusion in the axial direction is a bevel surface, and the rear end of the third limiting protrusion in the axial direction is a bevel surface, so that when the mandrel is fixed with the expansion sleeve, the bevel surface of the third limiting protrusion is in contact with the bevel surface of the second limiting protrusion, the inner hole of the expansion sleeve is expanded, the third limiting protrusion slides into the expansion sleeve, and the second limiting protrusion slides into the limiting groove, so that the fixing between the mandrel and the expansion sleeve is realized.

[0025] Preferably, the mandrel comprises a thick segment and a thin segment which are threadedly matched with each other, the thick segment is located in the second positioning hole, the base body is provided with a second limiting hole which is radially penetrated, the second limiting hole is communicated with the second positioning hole, the thick segment of the mandrel is provided with a second long hole which is laterally opened and axially extended, and the second limiting hole is matched with a second limiting piece, and the end of the second limiting piece is located in the second long hole.

[0026] When the mandrel is installed, the mandrel is divided into a thick segment and a thin segment which are threadedly matched with each other, so as to facilitate the installation of the mandrel. The second limiting piece can limit the rotation of the thick segment of the mandrel, so as to avoid the relative rotation between the thick segment and the thin segment, and ensure that the axial length of the mandrel is unchanged. The second limiting hole and the second limiting piece can be a bolt or a pin.

[0027] Preferably, the expansion sleeve is provided with a third long hole which is radially penetrated and axially extended, the expansion portion is provided with a third limiting hole which is radially extended and corresponds to the third long hole, and the third limiting hole is matched with a third limiting piece which limits the circumferential rotation of the expansion sleeve.

[0028] The third limiting piece can avoid the rotation of the expansion sleeve, so as to avoid the rotation of the expansion sleeve scratching the inner wall of the annular workpiece, and can ensure that the runout value of the expansion sleeve is unchanged.

[0029] The present application has the following advantages: by adjusting the cooperation of the groove, the first adjusting hole and the first adjusting bolt, the positioning sleeve has a tendency to move towards the step surface when it is fixed, when the flatness of the positioning sleeve does not meet the requirements, the first adjusting bolt can be screwed to finely adjust the flatness of the annular workpiece. At the same time, the positioning sleeve can be tightly attached to the step surface, and when the flatness of the step surface meets the requirements, the flatness of the positioning sleeve can be further ensured, so that the positioning sleeve is more accurate when positioning the annular workpiece. At the same time, the concentricity of the mandrel can be adjusted, and the rotation of the mandrel and the expansion sleeve can be avoided, so as to further ensure the positioning accuracy. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 It is a structural schematic diagram of the present application.

[0031] Figure 2 It is a structural schematic diagram of the present application after the positioning sleeve is placed.

[0032] Figure 3Structure schematic diagram of the present application when clamping the annular workpiece.

[0033] Figure 4 Structure schematic diagram of the present application when clamping the annular workpiece. Figure 2 Structure schematic diagram of the present application when clamping the annular workpiece.

[0034] Figure 5 Structure schematic diagram of the present application when clamping the annular workpiece. Figure 2 Structure schematic diagram of the present application when clamping the annular workpiece.

[0035] Figure 6 Structure schematic diagram of the present application when clamping the annular workpiece.

[0036] Figure 7 Structure schematic diagram of the present application when clamping the annular workpiece.

[0037] Figure 8 Structure schematic diagram of the present application when clamping the annular workpiece.

[0038] Figure 9 Structure schematic diagram of the present application when clamping the annular workpiece.

[0039] Figure 10 Structure schematic diagram of the present application when clamping the annular workpiece.

[0040] Figure 11 Structure schematic diagram of the present application when clamping the annular workpiece.

[0041] Annular workpiece 100, small-diameter section 1, adjusting groove 11, first limiting hole 12, large-diameter section 2, large-diameter section fixing hole 21, step 22, matching protrusion 23, base body 3, base fixing hole 31, base screw hole 32, second limiting hole 33, second adjusting hole 34, mandrel 4, thin section 41, first long hole 411, thick section 42, first limiting protrusion 421, second long hole 422, third limiting protrusion 43, threaded connection section 44, mandrel head 45, expansion sleeve 5, third long hole 51, second limiting protrusion 52, opening part 6, third limiting hole 61, positioning sleeve 7, first adjusting hole 71, through hole 72, avoiding groove 73, first positioning hole 81, second positioning hole 82, matching hole 83. DETAILED DESCRIPTION

[0042] The present application will be further described below according to the drawings and specific embodiments.

[0043] As Figure 1 , Figure 2 , Figure 3 and Figure 4As shown, the embodiment discloses a kind of auxiliary fixture for finishing outer circle surface of ring piece, from top to bottom successively including fixture body and base body 3, fixture body includes small diameter section 1 and large diameter section 2 from top to bottom, the upper end of small diameter section 1 is connected with strutting open part 6, the lower end of base body 3 is equipped with base fixed hole 31 for being fixed with machine tool.The expansion sleeve 5 is sleeved on strutting open part 6, the inner wall of expansion sleeve 5 is in contact with the outer wall of strutting open part 6, and the contact surface of expansion sleeve 5 and strutting open part 6 is tapered surface, the inner diameter of the inner hole of expansion sleeve 5 gradually increases from top to bottom, the outer diameter of strutting open part 6 gradually increases from top to bottom.The diameter of small diameter section 1 is less than the diameter of large diameter section 2, the connecting place of small diameter section 1 and large diameter section 2 forms step 22, step 22 is supported with positioning sleeve 7, positioning sleeve 7 is annular, and the inner wall of positioning sleeve 7 is in contact with the outer wall of small diameter section 1.Large diameter section 2 is equipped with large diameter section fixed hole 21, and the axial direction is up and down direction, base body 3 is equipped with base screw hole 3, and the axial direction is up and down direction, and large diameter section 2 and base body 3 are fixed together by bolt (not shown in the figure).

[0044] As Figure 1 、 Figure 2 、 Figure 4 、 Figure 5 、 Figure 7 As shown, positioning sleeve 7 is equipped with three first adjusting holes 71, which are uniformly spaced along the circumferential direction, and first adjusting hole 71 penetrates the inner wall and outer wall of positioning sleeve 7 along the radial direction.Three adjusting grooves 11 are provided on small diameter section 1, which are uniformly spaced along the circumferential direction and laterally open, and the adjusting groove 11 is in a hemispherical structure, the width of the hemispherical adjusting groove 11 gradually decreases from the opening to the bottom;Adjusting groove 11 corresponds to first adjusting hole 71 one by one, the center line of adjusting groove 11 is located at the lower end of the center line of first adjusting hole 71, i.e. the center line of adjusting groove 11 is closer to step 22 than the center line of first adjusting hole 71, first adjusting hole 71 is threadedly connected with first adjusting bolt (not shown in the figure), and the end of first adjusting bolt is in contact with adjusting groove 11 when first adjusting bolt is screwed into first adjusting hole 71, positioning sleeve 7 has the tendency to approach step 22 under the action of first adjusting bolt, so that the lower end surface of positioning sleeve 7 tightly abuts the step surface of step 22.

[0045] As Figure 1 、 Figure 2 、 Figure 4 、 Figure 5 、 Figure 7As shown, the small-diameter section 1 and the distraction portion 6 are each provided with a first positioning hole 81 extending in the axial direction from top to bottom, the mandrel 4 sequentially includes a thin section 41 and a thick section 42 from top to bottom, the thin section 41 of the mandrel is located in the first positioning hole 81, and the circumferential outer wall of the thin section 41 is in contact with the circumferential inner wall of the first positioning hole 81. The small-diameter section 1 is provided with three first limiting holes 12 uniformly and circumferentially spaced, each first limiting hole 12 is located between two adjacent adjusting grooves 11, the first limiting hole 12 radially penetrates the inner wall and the outer wall of the small-diameter section 1 and communicates with the first positioning hole 81. The positioning sleeve 7 is provided with three through holes 72 uniformly and circumferentially spaced and radially penetrating the inner wall and the outer wall of the positioning sleeve 7, the through hole 72 corresponds to the first limiting hole 12 one by one, the first limiting hole 12 is threadedly fitted with a first limiting member (not shown in the figure), the first limiting member is a bolt, the first limiting member sequentially passes through the through hole 72, the first limiting hole 12 from outside to inside, and the end of the first limiting member is in contact with the outer wall of the thin section 41 of the mandrel. The thin section 41 of the mandrel is provided with a first long hole 411 opening laterally and extending in the axial direction from top to bottom, the end of one of the three first limiting members enters the first long hole 411 to limit the circumferential rotation of the thin section 41 of the mandrel.

[0046] As shown in Figures 3 to 6 The upper end of the large-diameter section 2 is provided with a matching hole 83 opening to the side of the small-diameter section 1 (opening upward), the lower end of the small-diameter section 1 is provided with a matching protrusion 23 extending to the side of the large-diameter section 2 (extending downward), the matching protrusion 23 extends into the matching hole 83, and the axial length of the matching protrusion 23 is less than the axial depth of the matching hole 83. The matching protrusion 23 is annular, and the circumferential outer wall of the matching protrusion 23 is in contact with the circumferential inner wall of the matching hole 83. The upper end of the base body 3 is provided with four second adjusting holes 34 uniformly and circumferentially spaced, the second adjusting hole 34 extends in the radial direction and penetrates the large-diameter section 2, the second adjusting hole 34 communicates with the matching hole 83, and the second adjusting hole 34 is threadedly fitted with a second adjusting bolt (not shown in the figure). The second adjusting bolt is threadedly fitted with the second adjusting hole 34 and the end is in contact with the circumferential outer wall of the matching protrusion 23.

[0047] As shown in Figure 4 and Figure 5As shown, the thin section 41 and the thick section 42 of the mandrel 4 are threadedly connected through a threaded section 44, which includes the thin section 41 provided with a downwardly extending screw rod and the thick section 42 provided with an upwardly opening internal threaded hole, the screw rod threadedly cooperating with the internal threaded hole. The large diameter section 2 is also provided with a first positioning hole 81, and the large diameter section 2 and the base body 3 are provided with a second positioning hole 82, the first positioning hole 81 and the second positioning hole 82 being coaxially arranged and in communication. The diameter of the first positioning hole 81 is smaller than the diameter of the second positioning hole 82, and the internal hole enclosed by the cooperating protrusion 23 coincides with the second positioning hole 82. The thick section 42 of the mandrel 4 is located in the second positioning hole 82, and the inner wall of the second positioning hole 82 is in contact with the outer wall of the thick section 42. A cooperating hole 83 is in communication with the second positioning hole 82, the diameter of the cooperating hole 83 is larger than the diameter of the second positioning hole 82, and the portion of the thick section 42 of the mandrel 4 located in the cooperating hole 83 is provided with a radially extending first limiting protrusion 421, the first limiting protrusion 421 is annular, and the thickness of the first limiting protrusion 421 in the axial direction is smaller than the distance between the bottom of the cooperating protrusion 23 and the bottom of the cooperating hole 83.

[0048] As shown in Figure 1 , Figure 4 and Figure 5 , the base body 3 is provided with a radially penetrating second limiting hole 33, and the second limiting hole 33 is in communication with the second positioning hole 82. The thick section 42 of the mandrel 4 is provided with a second long hole 422 extending in the upward and downward direction in the axial direction and laterally opening, and the second limiting hole 33 threadedly cooperates with a second limiting member (not shown in the figure), which is a bolt, and the end of the second limiting member enters the second long hole 422 to limit the circumferential rotation of the thick section 42.

[0049] As shown in Figure 2 and Figure 8 , the inner edge of the upper end of the positioning sleeve 7 is provided with an upwardly opening avoiding slot 73, the avoiding slot 73 extends radially inwardly and is in communication with the internal hole of the positioning sleeve 7, and the depth of the avoiding slot 73 gradually increases from outside to inside. The number of the avoiding slots 73 is five and is uniformly spaced in the circumferential direction.

[0050] As shown in Figures 9 to 11 , the upper end of the mandrel 4 is provided with a radially outwardly opening limiting slot 55, the upper end of the expansion sleeve 5 is provided with a radially inwardly extending second limiting protrusion 52, and the second limiting protrusion 52 extends into the limiting slot 55. The top of the mandrel 4 is a mandrel head 45, and the diameter of the mandrel head 45 is larger than the internal diameter of the expansion sleeve 5. The mandrel 4 is provided with a radially outwardly extending third limiting protrusion 43 at the lower end of the limiting slot 55, the upper end surface of the second limiting protrusion 52 is beveled, the width of the second limiting protrusion 52 in the upward and downward direction in the axial direction gradually decreases from outside to inside, and the width of the third limiting protrusion 43 in the upward and downward direction in the axial direction gradually increases from outside to inside. The second limiting protrusion 52, the third limiting protrusion 43 and the limiting slot 55 are all annular.

[0051] AsFigure 8 and Figure 11 As shown in the figure, the sleeve 5 is provided with two third long holes 51 which are radially penetrated and axially extended, the opening part 6 is provided with third limiting holes 61 which are radially extended and correspond to the third long holes 51, and the third limiting holes 61 are matched with third limiting members (not shown in the figure) which limit the rotation of the sleeve 5 in the circumferential direction.

[0052] In use, the operator fixes the base body 3 on the machine tool, and at the same time, the oil cylinder is fixed with the lower end of the mandrel 4, then the detection end of the micrometer gauge is hit on the stepped surface of the step 22, and whether the run-out value of the stepped surface meets the standard is detected, if the run-out value does not meet the standard, the second adjusting bolt is screwed, the stepped surface of the step 22 is leveled, and then the micrometer gauge is measured again. After the stepped surface meets the standard, the positioning sleeve 7 is sleeved on the small-diameter section 1, then the first adjusting bolt is screwed into the first adjusting hole 71, so that the end of the first adjusting bolt is in contact with the groove wall of the adjusting groove 11, the lower end of the positioning sleeve 7 is tightly attached to the stepped surface of the step 22, then the micrometer gauge is hit on the outer edge surface of the upper end surface of the positioning sleeve 7, and the run-out value is detected, if it does not meet the standard, the first adjusting bolt is rotated, and then the micrometer gauge is measured again. After the flatness of the positioning sleeve 7 meets the standard, the operator inserts the first limiting member into the through hole 72 and screws it into the first limiting hole 12, so that the end of the first limiting member is in contact with the outer wall of the mandrel 4, then the micrometer gauge is hit on the upper end of the mandrel 4, and the run-out value of the mandrel 4 is detected, if it does not meet the standard, the first limiting member is screwed, and then the micrometer gauge is measured again. After the run-out value of the mandrel meets the standard, the second limiting member is inserted into the second limiting hole 33 and the third limiting member is inserted into the third limiting hole 61.

[0053] Then the annular workpiece 100 is placed on the positioning sleeve 7, the center of the machine tool will be in contact with the annular workpiece 100, so that the end surface of the annular workpiece 100 is in contact with the upper end surface of the positioning sleeve 7, then the oil cylinder of the machine tool pulls the mandrel 4, so that the mandrel 4 extrudes the sleeve 5, the sleeve 5 opens and clamps the annular workpiece 100, and then the outer cylindrical surface of the annular workpiece 100 is finished.

Claims

1. An auxiliary fixture for finishing the outer cylindrical surface of a ring-shaped part, comprising a base body for fixing to a machine tool and a fixture body for positioning the ring-shaped workpiece, the fixture body being fixed to the front end of the base body, the fixture body comprising a large-diameter section near the base body and a small-diameter section away from the base body, a step being formed at the connection between the large-diameter section and the small-diameter section, a positioning sleeve being fitted on the small-diameter section, one end face of the positioning sleeve contacting the end face of the step, and the other end face of the positioning sleeve being used to contact the end face of the ring-shaped workpiece; a spreading part is connected to the front end of the small-diameter section, and an expansion sleeve for expanding and tightening the inner hole of the ring-shaped workpiece is fitted on the spreading part, the contact surfaces between the expansion sleeve and the spreading part are both conical surfaces, and the expansion sleeve is equipped with a mandrel for realizing axial movement of the expansion sleeve; characterized in that: The outer wall of the small-diameter section is provided with at least three radially extending adjustment grooves evenly spaced circumferentially. The adjustment grooves are hemispherical or conical structures that gradually narrow from the opening to the bottom. The positioning sleeve is provided with a first adjustment hole that corresponds to each adjustment groove and penetrates radially. The adjustment grooves and the first adjustment holes are not concentric; the centerline of the adjustment groove is closer to the step than the centerline of the first adjustment hole. A first adjustment bolt is threaded into the first adjustment hole. When the first adjustment bolt is screwed into the first adjustment hole and contacts the adjustment groove, the positioning sleeve has a tendency to move towards the step, causing one end face of the positioning sleeve to fit tightly against the end face of the step. The clamp body... Both the expansion section and the support section are provided with axially extending first positioning holes for positioning the mandrel, and the outer wall of the mandrel contacts the inner wall of the first positioning hole; the small diameter section is provided with at least three circumferentially evenly spaced and radially penetrating first limiting holes, the first limiting holes are connected to the first positioning holes, the first limiting holes are threadedly fitted with first limiting members, and the end of the first limiting member contacts the outer wall of the mandrel; the positioning sleeve is provided with radially penetrating through holes that correspond one-to-one with the first limiting holes, the outer wall of the mandrel is provided with a laterally open and axially extending first elongated hole, and the first limiting member passes through the through hole, the first limiting hole and the first elongated hole from the outside to the inside in sequence to restrict the circumferential rotation of the mandrel.

2. The auxiliary fixture for finishing the outer cylindrical surface of an annular part according to claim 1, characterized in that: The base body is provided with a mating hole that opens towards the large diameter section. The bottom of the large diameter section is provided with a mating protrusion that extends into the mating hole. The outer wall of the mating protrusion contacts the inner wall of the mating hole. The base body is provided with at least three second adjustment holes that are evenly spaced circumferentially and penetrate radially. The second adjustment holes are threaded with second adjustment bolts. The end of the second adjustment bolt contacts the outer wall of the mating protrusion.

3. The auxiliary fixture for finishing the outer cylindrical surface of an annular part according to claim 1, characterized in that: The positioning sleeve has several axially opening clearance grooves at its front inner edge. The depth of the clearance grooves gradually increases from the radial outer side to the radial inner side, and the clearance grooves are connected to the inner hole of the positioning sleeve.

4. The auxiliary fixture for finishing the outer cylindrical surface of an annular part according to claim 2, characterized in that: Both the large-diameter section and the base body are provided with an axially extending second positioning hole. The second positioning hole is connected to and coaxially arranged with the mating hole. The inner diameter of the mating hole is larger than the inner diameter of the second positioning hole. The outer wall of the mandrel is in contact with the inner wall of the second positioning hole. The portion of the mandrel located in the mating hole is provided with a first limiting protrusion that extends radially outward to limit the axial movement stroke of the mandrel.

5. The auxiliary fixture for finishing the outer cylindrical surface of an annular part according to claim 1, 2, or 3, characterized in that: The front end of the mandrel is provided with a limiting groove that opens radially outward, and the front end of the expansion sleeve is provided with a second limiting protrusion that extends radially inward and into the limiting groove.

6. The auxiliary fixture for finishing the outer cylindrical surface of an annular part according to claim 5, characterized in that: The front end face of the second limiting protrusion along the axial direction is a slope, and the width of the second limiting protrusion along the axial direction gradually decreases from the radially outer side to the radially inner side. The mandrel is provided with a third limiting protrusion extending radially outward. The third limiting protrusion is located at the rear end of the limiting groove along the axial direction. The rear end face of the third limiting protrusion along the axial direction is a slope, and the width of the third limiting protrusion along the axial direction gradually increases from the radially outer side to the radially inner side.

7. The auxiliary fixture for finishing the outer cylindrical surface of an annular part according to claim 4, characterized in that: The mandrel includes a thick section and a thin section that are threaded together. The thick section is located in the second positioning hole. The base body is provided with a second limiting hole that penetrates radially. The second limiting hole communicates with the second positioning hole. The thick section of the mandrel is provided with a second elongated hole that opens laterally and extends axially. The second limiting hole is equipped with a second limiting member. The end of the second limiting member is located in the second elongated hole.

8. The auxiliary fixture for finishing the outer cylindrical surface of an annular part according to claim 1, 2, or 3, characterized in that: The expansion sleeve is provided with a third elongated hole that penetrates radially and extends axially. The expansion portion is provided with a third limiting hole that extends radially and corresponds to the third elongated hole. The third limiting hole is equipped with a third limiting member that restricts the circumferential rotation of the expansion sleeve.

Images