Positioning tool and machining structure for combined tooth electric spark machining

Abstract

The utility model discloses a positioning tool and a machining structure for combined gear electric spark machining, according to the positioning tool for combined gear electric spark machining, a bottom plate is used for supporting and connecting all parts and ensuring the position relation of all the parts, and a positioning core column is used for being matched with an inner hole of a combined gear to achieve coarse positioning of the combined gear on the bottom plate; the positioning pin is matched with the positioning hole in the tooth-shaped positioning plate to realize accurate positioning of the combined gear on the bottom plate, and the tooth-shaped positioning part is matched with the notch in the outer tooth to realize circumferential positioning and limiting of the tooth shape of the combined gear on the bottom plate; the positioning tool is easy to use, circumferential positioning installation of the tooth profile of the combined gear is achieved, the problem that circumferential positioning is difficult when the combined gear is clamped at present can be effectively solved, the machining efficiency can be improved, and the precision of electric spark machining of the tooth tip is guaranteed.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the technical field of machining, specifically relates to a positioning tool and machining structure for combined tooth electric spark machining. BACKGROUND

[0002] The combined gear is a gear structure composed of an outer tooth part and a boss part, and has the feature of a hollow hub, such as a combined tooth forging process in Chinese patent CN111730021A, the outer tooth of part of the combined gear narrows in width away from one end of the boss to form a tooth tip, which has the advantages of good structural strength and stable transmission; the missing tooth gear is a gear structure in which part of the teeth is removed in the circumferential direction of the conventional gear, and a plurality of notches are formed on the tooth surface, and due to the notches on the tooth surface, the missing tooth gear will produce some special motion states during rotation; therefore, in some special mechanical systems, the special combined gear with the missing tooth gear feature and the outer tooth with the tooth tip as shown in the drawings is often used to meet the special rotation conditions. Figure 1 、 Figure 2 and Figure 3

[0003] At present, the machining of the outer tooth part of the combined gear is generally to first mill the outer tooth part on the boss blank, and then grind the outer tooth to form, but the grinding forming has low machining efficiency, and for the above-mentioned special combined gear, the machining precision of the outer tooth and the tooth tip is also limited. Electric spark machining is a method of realizing precise machining by gradually eroding the metal material through the pulse spark discharge between the tool electrode and the workpiece. Therefore, in order to improve the tooth profile precision, the above-mentioned tooth tip of the special combined gear generally needs to be further processed by electric spark machining. In order to electrically spark the tooth tip of the above-mentioned special combined gear, the applicant tried to use a chuck to clamp, but found that due to the fact that the chuck is clamped and fixed by clamping the outer cylindrical surface of the hub part of the combined gear in the radial direction, and lacks circumferential positioning, it is difficult to position the outer tooth in the circumferential direction during electric spark machining, which not only leads to long clamping time, but also easily affects the machining precision of the tooth tip, and is not suitable for mass production. SUMMARY

[0004] In view of the above shortcomings of the prior art, the purpose of the utility model is to provide a positioning tool and machining structure for combined tooth electric spark machining, which solves the technical problem of the difficulty of circumferential positioning of the above-mentioned special combined gear during clamping, and achieves the effect of improving the clamping speed and machining precision.

[0005] To solve the above technical problems, the utility model adopts the following technical scheme:

[0006] ​The utility model provides a kind of positioning tool for combined gear electric spark machining, including transverse bottom plate, bottom plate has vertically upward protruding positioning core column and positioning pin, positioning core column is used to cooperate with the inner hole of combined gear, and positioning pin has multiple and is distributed in the form of circumference with positioning core column as center;It further includes tooth-shaped positioning plate that is arranged in parallel and is spaced above bottom plate and is annular, a plurality of positioning holes are vertically provided on tooth-shaped positioning plate, positioning pin passes through positioning hole one by one and is slidably fitted, so that tooth-shaped positioning plate can slide along positioning pin, and the inner hole of tooth-shaped positioning plate is coaxial with positioning core column;The diameter of the inner hole of tooth-shaped positioning plate is greater than the diameter of positioning core column, and a plurality of radially protruding tooth-shaped positioning portions are distributed in the form of circumference on the inner hole wall of tooth-shaped positioning plate, and tooth-shaped positioning portion is used to cooperate with the notch on the outer tooth of combined gear one by one.

[0007] Further, a pressing plate parallel to the bottom plate is arranged above the positioning core column, a connecting hole is vertically provided on the pressing plate, a bolt is slidably provided in the connecting hole, the head of the bolt abuts against the upper surface of the pressing plate, and the tail of the bolt is downwardly connected with the positioning core column or the bottom plate in a threaded manner.

[0008] Further, the pressing plate has a clearance notch extending from the side surface thereof to the connecting hole, and the width of the clearance notch is greater than or equal to the diameter of the connecting hole.

[0009] Further, an installation hole is vertically provided on the bottom plate, the positioning core column is a component independent of the bottom plate, and the lower end of the positioning core column is located in the installation hole.

[0010] Further, a clearance hole is vertically provided on the positioning core column, a gas cylinder with an upwardly extending telescopic rod is connected to the bottom plate below the positioning core column in a vertically extending manner, the telescopic rod of the gas cylinder extends into the clearance hole and is slidably fitted, and the tail of the bolt is connected with the telescopic rod of the gas cylinder in a threaded manner through the clearance hole.

[0011] Further, a cushion block is connected to the pressing plate below, and the lower end of the cushion block is lower than the gas cylinder, so as to support the positioning tool.

[0012] Further, a plurality of pin holes are formed in the upper surface of the bottom plate, the positioning pins are components independent of the bottom plate, the positioning pins correspond to the pin holes one by one, and the lower ends of the positioning pins are located in the corresponding pin holes.

[0013] Further, the upper end of the positioning pin has a taper.

[0014] The utility model also includes a kind of processing structure for combined tooth electric spark machining, the processing structure includes the combined gear to be processed and the positioning tooling for combined tooth electric spark machining as described above, the combined gear is vertically contacted between bottom plate and pressing plate, and is sleeved outside positioning core column, the diameter of positioning core column is matched with the inner hole diameter of the combined gear;Tooth profile positioning plate is contacted on the step surface of the combined gear, and is sleeved outside the external tooth of the combined gear, the inner hole diameter of tooth profile positioning plate is greater than the external tooth diameter of the combined gear, the size of tooth profile positioning part is matched with the notch on the external tooth of the combined gear, tooth profile positioning part is located in the notch one-to-one.

[0015] Compared with the prior art, the utility model has the beneficial effects that:

[0016] The positioning tooling for combined tooth electric spark machining, the bottom plate is used for supporting, connecting each component and ensuring the positional relationship of each component, the positioning core column is used for cooperating with the inner hole of the combined gear, to realize the coarse positioning of the combined gear on the bottom plate, the positioning pin cooperates with the positioning hole on the tooth profile positioning plate, to realize the accurate positioning of the combined gear on the bottom plate, the tooth profile positioning part cooperates with the notch on the external tooth, to realize the circumferential positioning and limiting of the combined gear tooth profile on the bottom plate;The positioning tooling is not only simple to use, and realizes the circumferential positioning installation of the combined gear tooth profile, can effectively solve the problem of circumferential positioning difficulty of the present clamping combined gear, is favorable for improving processing efficiency, guaranteeing the precision of electric spark machining tooth tip. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The front view of the combined gear with notched external tooth for background technology;

[0018] Figure 2 The cross-sectional view of the combined gear with notched external tooth for background technology;

[0019] Figure 3 For Figure 2 The local enlarged view of external tooth;

[0020] Figure 4 The front view of the processing structure for combined tooth electric spark machining for embodiment;

[0021] Figure 5 The cross-sectional view of the processing structure for combined tooth electric spark machining for embodiment;

[0022] Figure 6 The front view of the tooth profile positioning plate for embodiment;

[0023] Wherein, the bottom plate 1, positioning core column 2, positioning pin 3, tooth-shaped positioning plate 4, positioning hole 5, tooth-shaped positioning part 6, combination gear 7, external tooth 8, notch 9, pressing plate 10, bolt 11, give way gap 12, give way hole 13, cylinder 14, telescopic rod 15, cushion block 16, tooth tip 17. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model more clear, the technical scheme in the embodiments of the utility model will be clearly and completely described below in combination with the drawings in the embodiments of the utility model.

[0025] Embodiment:

[0026] Please see Figure 4 、 Figure 5 and Figure 6 A kind of positioning tool for combination tooth electric spark machining, including transverse bottom plate 1, bottom plate 1 has vertically upward protruding positioning core column 2 and positioning pin 3, positioning core column 2 is used to cooperate with the inner hole of combination gear 7 (the special combination gear described in the background art), positioning pin 3 has multiple and is distributed in the form of circle with positioning core column 2 as center;It also includes tooth-shaped positioning plate 4 that is arranged in parallel and interval above bottom plate 1 and is annular, multiple positioning holes 5 are vertically and through in tooth-shaped positioning plate 4, positioning pin 3 is slidably fitted through positioning hole 5 one by one, so that tooth-shaped positioning plate 4 can slide along positioning pin 3, the inner hole of tooth-shaped positioning plate 4 is coaxial with positioning core column 2;The diameter of the inner hole of tooth-shaped positioning plate 4 is greater than the diameter of positioning core column 2, multiple radial tooth-shaped positioning parts 6 are distributed in the form of circle on the inner hole wall of tooth-shaped positioning plate 4, tooth-shaped positioning part 6 is used to cooperate with the notch 9 on the external tooth 8 of combination gear 7 one by one.

[0027] The positioning tool for combination tooth electric spark machining of the utility model, when using, first make tooth-shaped positioning plate 4 slide upwards and separate from positioning pin 3, take down tooth-shaped positioning plate 4; Figure 1 、 Figure 2 and Figure 3As shown, the engaging gear 7 is shaped like a boss, with notches 9 on its external teeth 8 and tooth tips 17 at the end of the external teeth away from the boss. With the smaller outer diameter end of the engaging gear 7 facing upwards, a tooth-shaped positioning plate 4 with an inner diameter larger than the diameter of the external teeth 8 of the engaging gear 7 is fitted onto the external teeth 8 of the engaging gear 7, and the tooth-shaped positioning part 6 is fitted into the notches 9 on the external teeth 8 one-to-one. Then, the engaging gear 7 is fitted onto the positioning core 2, with the positioning core 2 engaging with the inner hole of the engaging gear 7 to roughly position the center of the engaging gear 7. The engaging gear 7 is then fitted and placed on the bottom. During the process on plate 1, the rotating and adjusting gear 7 and toothed positioning plate 4 are used to make the positioning pin 3 pass through the positioning hole 5 of the toothed positioning plate 4 one-to-one, thereby accurately positioning the tooth position and restricting the circumferential rotation of the gear 7. The toothed positioning plate 4 and the toothed positioning part 6 do not obstruct the tooth tip 17 in the axial direction, so as not to affect the processing of the tooth tip 17. In practice, the thickness of the toothed positioning plate 4 can also be controlled so that the toothed positioning plate 4 is lower than the root of the tooth tip 17 in the clamping state, so as to leave more operating space for the processing of the tooth tip 17 and ensure smooth processing.

[0028] The positioning fixture for EDM of the gear described in this utility model has a base plate 1 for supporting and connecting various components and ensuring their positional relationship. The positioning core 2 is used to cooperate with the inner hole of the gear 7 to achieve coarse positioning of the gear 7 on the base plate 1. The positioning pin 3 cooperates with the positioning hole 5 on the tooth-shaped positioning plate 4 to achieve precise positioning of the gear 7 on the base plate 1. The tooth-shaped positioning part 6 cooperates with the notch 9 on the external tooth 8 to achieve circumferential positioning and limiting of the tooth shape of the gear 7 on the base plate 1. This positioning fixture is not only simple to use, but also achieves circumferential positioning and installation of the tooth shape of the gear 7. It can effectively solve the problem of circumferential positioning difficulties in clamping the gear 7, which is conducive to improving processing efficiency and ensuring the accuracy of the gear tip 17 in EDM.

[0029] Please see Figure 4 and Figure 5 Above the positioning core 2, there is a pressure plate 10 parallel to the base plate 1. A connecting hole is vertically through the pressure plate 10. A bolt 11 is slidably through the connecting hole. The head of the bolt 11 abuts against the upper surface of the pressure plate 10, and the tail of the bolt 11 faces downward and is threadedly connected to the positioning core 2 or the base plate 1.

[0030] Before use, unscrew bolt 11 to remove pressure plate 10, install it on gear 7, place pressure plate 10 above gear 7, and tighten bolt 11 to press gear 7 firmly onto base plate 1, thus completely fixing gear 7 and preventing accidental movement of gear 7 during processing. This not only ensures smooth processing but also helps improve processing accuracy.

[0031] Please see Figure 4 and Figure 5The pressing plate 10 is provided with a clearance gap 12 extending from the side of the pressing plate 10 to the connecting hole, and the width of the clearance gap 12 is greater than or equal to the diameter of the connecting hole.

[0032] Therefore, when the gear 7 is installed or removed, the pressing plate 10 can be transversely removed through the clearance gap 12 by loosening the bolt 11 upwardly to a certain height, without completely unscrewing the bolt 11, so that the positioning tool is more convenient to use and the practicability of the positioning tool is improved.

[0033] Please refer to Figure 4 and Figure 5 , the bottom plate 1 is vertically provided with a mounting hole, the positioning core column 2 is a component independent of the bottom plate 1, and the lower end of the positioning core column 2 is located in the mounting hole.

[0034] Therefore, the positioning core column 2 and the bottom plate 1 are independent components, which are convenient to process and improve the dimensional accuracy of the positioning core column 2, and the positioning core column 2 is matched with the mounting hole and the inner hole of the gear 7 through the outer cylindrical surface, which is beneficial to improve the position degree of the gear 7 on the bottom plate 1, so as to realize the precise positioning of the gear 7 by cooperating with the positioning pin 3 and the tooth-shaped positioning plate 4.

[0035] Correspondingly, please refer to Figure 4 and Figure 5 , the upper surface of the bottom plate 1 is provided with a plurality of pin holes, the positioning pin 3 is a component independent of the bottom plate 1, the positioning pin 3 corresponds to the pin hole one by one, and the lower end of the positioning pin 3 is located in the corresponding pin hole.

[0036] Therefore, the positioning pin 3 and the bottom plate 1 are also independent components, which are convenient to process and improve the dimensional accuracy of the positioning pin 3, and the positioning pin 3 is matched with the pin hole and the positioning hole 5 on the tooth-shaped positioning plate 4 through the outer cylindrical surface, so as to improve the position degree of the gear 7 on the bottom plate 1 by cooperating with the positioning core column 2 and realize the precise positioning of the gear 7.

[0037] In this embodiment, the upper end of the positioning pin 3 is tapered, so that the positioning pin 3 is more easily inserted into the positioning hole 5 when the tooth-shaped positioning plate 4 is installed downwardly, which is beneficial to reduce the difficulty of using the positioning tool and improve the practicability of the positioning tool.

[0038] Please refer to Figure 4 and Figure 5 , the positioning core column 2 is provided with a clearance hole 13, the bottom plate 1 is vertically connected with an upward cylinder 14 having a telescopic rod 15, the telescopic rod 15 of the cylinder 14 extends into the clearance hole 13 and is slidingly matched, the tail of the bolt 11 is threadedly connected with the telescopic rod 15 of the cylinder 14 through the clearance hole 13, and the tail of the bolt 11 is indirectly connected with the bottom plate 1 through the cylinder 14.

[0039] Thus, in use, only the cylinder 14 action needs to be controlled, the bolt 11 is driven up and down through the telescopic rod 15, the pressing plate 10 can be loosened and taken out transversely, or the pressing plate 10 is pressed down to tightly combine with the gear 7.

[0040] In the embodiment, the pressing plate 10 is connected with the cushion block 16 below, the lower end of the cushion block 16 is lower than the cylinder 14, so as to install the supporting positioning tool on the machining equipment; the symmetry of the tooth tip 17 clamped and machined by the contrast chuck is above 0.1mm, the positioning tool is clamped and machined, the symmetry of the tooth tip 17 can be controlled within 0.03mm, and the circumferential positioning of the repeatedly rotating gear 7 is simpler and more reliable, so that the machining efficiency is doubled.

[0041] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit the technical solutions, those skilled in the art should understand that the technical solutions of the present application are modified or replaced, without departing from the purpose and scope of the present application, which should be covered in the scope of the claims of the present application.

Claims

1. A positioning tool for electric discharge machining with a tooth, characterized by: The positioning jig comprises a horizontal base plate, a vertical positioning core column and a positioning pin vertically protruding from the base plate, the positioning core column is used for matching with an inner hole of a gear, the positioning pin is in one-to-one correspondence with the positioning core column, and the positioning pin is vertically protruding from the base plate; a tooth-shaped positioning plate is arranged above the base plate in parallel and in a ring shape, a plurality of positioning holes are vertically arranged on the tooth-shaped positioning plate, the positioning pin passes through the positioning hole in a sliding fit, the tooth-shaped positioning plate is slidable along the positioning pin, and an inner hole of the tooth-shaped positioning plate is coaxial with the positioning core column; a diameter of the inner hole of the tooth-shaped positioning plate is greater than a diameter of the positioning core column, a plurality of tooth-shaped positioning portions are radially protruding from a hole wall of the inner hole of the tooth-shaped positioning plate in a circumferential direction, and the tooth-shaped positioning portions are used for matching with notches on outer teeth of the gear in one-to-one correspondence.

2. The positioning tool for electric discharge machining with a combination tooth according to claim 1, characterized in that: A pressing plate is arranged above the positioning core column in parallel with the base plate, a connecting hole is vertically arranged on the pressing plate, a bolt is slidably arranged in the connecting hole, a head of the bolt is in abutment with an upper surface of the pressing plate, and a tail of the bolt is downwardly connected with the positioning core column or the base plate in a threaded manner.

3. The positioning tool for electric discharge machining of a joint according to claim 2, characterized in that: The pressing plate has a gap in the side surface of the pressing plate, the gap extends to the connecting hole, and a width of the gap is greater than or equal to a diameter of the connecting hole.

4. The positioning tool for electric discharge machining of a joint according to claim 2, characterized in that: An installation hole is vertically arranged on the base plate, the positioning core column is a component independent of the base plate, and a lower end of the positioning core column is located in the installation hole.

5. The positioning tool for electric discharge machining of a joint according to claim 4, characterized in that: A gap is vertically arranged on the positioning core column, an upward cylinder of a telescopic rod is vertically connected below the base plate, a telescopic rod of the cylinder extends into the gap and is in a sliding fit, and the tail of the bolt is connected with the telescopic rod of the cylinder in a threaded manner through the gap.

6. The positioning tool for electric discharge machining of a joint according to claim 5, characterized in that: A cushion block is connected below the pressing plate, a lower end of the cushion block is lower than the cylinder, and the cushion block is used for installing and supporting the positioning jig.

7. The positioning tool for electric discharge machining of a joint according to claim 2, characterized in that: An upper surface of the base plate is provided with a plurality of pin holes, the positioning pin is a component independent of the base plate, the positioning pin is in one-to-one correspondence with the pin hole, and a lower end of the positioning pin is located in the corresponding pin hole.

8. The positioning tool for electric discharge machining of a joint according to claim 2, characterized in that: A taper is arranged at an upper end of the positioning pin.

9. A machining structure for combined tooth electrical discharge machining, characterized by: The positioning jig comprises a gear to be machined and the positioning jig for gear hobbing according to any one of claims 2 to 8, the gear to be machined is vertically abutted between the base plate and the pressing plate and is sleeved on the positioning core column, a diameter of the positioning core column is matched with an inner hole diameter of the gear to be machined, the tooth-shaped positioning plate is abutted on a stepped surface of the gear to be machined and is sleeved on outer teeth of the gear to be machined, an inner hole diameter of the tooth-shaped positioning plate is greater than an outer tooth diameter of the gear to be machined, a size of the tooth-shaped positioning portion is matched with a notch on the outer teeth of the gear to be machined, and the tooth-shaped positioning portion is in one-to-one correspondence with the notch.

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