Broach turning equipment

Abstract

The utility model provides broach turning equipment which comprises a broach, a follow rest, a first elastic center and an outer circle turning tool, the broach is a thin and long broach and is horizontally placed, and a center hole is formed in the left end of the broach and is connected with a machine tool spindle; a center hole in the right end is supported by the first elastic center; the follow rest is used for supporting the broach; the outer circle turning tool is installed on the tool turret and used for turning at the designated position of the surface of the broach.

Description

[Technical field]

[0001] The utility model relates to the technical field of broaches, in particular to a broach turning device. [Background technology]

[0002] A broach is a long rod-shaped tool with a handle and a bit. The handle is used to be installed on a machine tool, and the bit is used to cut the workpiece. The shape of the broach bit depends on the processing requirements. Common types include right-angle broaches, bevel broaches, and curved broaches.

[0003] Slender broaches belong to the category of slender shaft products. They deform greatly during turning and are prone to uneven centers, bulges, bamboo-like shapes, etc., which are difficult to achieve using the original processing methods. [Contents of the utility model]

[0004] In view of the shortcomings of the prior art, the purpose of this application is to provide a broach turning equipment, which solves the problems of broaches in the prior art such as concave-convex centers, waist drums, bamboo-node shapes, etc., and can effectively reduce cutting vibration and broach deformation.

[0005] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0006] A broach turning device, comprising:

[0007] Broach, follower rest, first elastic center and external turning tool, among which,

[0008] The broach is a slender broach placed horizontally, with a center hole at the left end of the broach connected to the machine tool spindle; the center hole at the right end is supported by the first elastic center;

[0009] The tool rest is used to support the broach;

[0010] The external cylindrical turning tool is mounted on a turret and is used for turning at a designated position on the broach surface.

[0011] Optionally, the tool rest is provided with three supporting cylindrical rods distributed in a herringbone shape. When turning, the broach is clamped in the middle of a channel formed by the three supporting cylindrical rods to support and position the broach.

[0012] Optionally, the broach turning equipment also includes a rotating body and a second elastic tip, the second elastic tip is arranged at the left end of the broach, a conical recess is arranged at the front end of the rotating body for supporting the center hole of the broach, and the rotating body and the second elastic tip can slide relative to each other.

[0013] Optionally, the rear end of the second elastic tip is fixed on the tailstock, and the front end is a cylinder inserted into the rear hole of the rotating body.

[0014] Optionally, the first elastic tip includes a steel ball, a spring ring, a plug and a screw, wherein the steel ball is located at one end of the elastic tip, the spring ring connects the steel ball and the first tip body, and when the steel ball abuts against the broach, the spring ring contracts; the plug is located above the steel ball and fixed by the screw.

[0015] Optionally, the tool rest is a trapezoidal structure with a circular through hole in the middle, the size of which is larger than the diameter of the broach.

[0016] Optionally, the tool rest is fixed on the machine tool guide rail through a base, and can move left and right along the guide rail to adjust the relative position with the broach. When the broach is rotating for turning, the tool rest remains stationary.

[0017] Optionally, when the broach generates axial deformation force during turning, under the action of the first elastic tip, the broach slides along the axial direction, releases part of the deformation stress, and automatically resets.

[0018] Compared with the prior art, the utility model has the following advantages:

[0019] In the utility model, the tool rest has three supporting cylindrical rods, and the broach is clamped between the three cylindrical rods during turning.

[0020] In the middle of the column, the external cylindrical turning tool works close to the tool rest, forming two pairs of radial pressures, which limit the up and down and left and right movement of the broach, and can only rotate around the axis. The tailstock center adopts an elastic center, which allows the broach to extend freely in the axial direction, effectively reducing cutting vibration and broach deformation without damaging the center hole.

Brief Description of the Drawings

[0021] Figure 1 It is a schematic diagram of the concave center appearing in the prior art;

[0022] Figure 2 It is a schematic diagram of the convexity in the prior art;

[0023] Figure 3 It is a schematic diagram of a waist drum in the prior art;

[0024] Figure 4 It is a schematic diagram of the bamboo-like appearance in the prior art;

[0025] Figure 5 Schematic diagram of the structure of the tool rest of this embodiment;

[0026] Figure 6 This is a schematic diagram of the first elastic top structure of this embodiment;

[0027] Figure 7 It is a schematic structural diagram of the broach turning equipment of this embodiment.

[0028] Figure numerals: broach 1, tool rest 2, three supporting cylindrical rods 3, first elastic tip 4, rotating body 5, second elastic tip 6, external cylindrical turning tool 7, steel ball 8, spring ring 9, plug 10, screw 11. [Specific implementation method]

[0029] The embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and is not to be construed as being limited to the embodiments described herein, but rather these embodiments are provided for a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not intended to limit the scope of protection of the present invention.

[0030] It should be understood that the various steps described in the method implementation of the present utility model can be performed in different orders and / or performed in parallel. In addition, the method implementation may include additional steps and / or omit the steps shown. The scope of the present utility model is not limited in this respect.

[0031] The term "including" and its variations used herein are open inclusions, i.e., "including but not limited to". The term "connected" may be directly connected or indirectly connected through intermediate components (elements). The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one other embodiment"; the term "some embodiments" means "at least some embodiments". The relevant definitions of other terms will be given in the following description.

[0032] It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish between devices, modules or units, and are not used to limit these devices, modules or units to be different devices, modules or units, nor are they used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0033] In the prior art, slender broaches may cause various problems during cutting, such as Figure 1-4 As shown:

[0034] According to the technical disclosure book Figures 1 to 4 ,The problems existing in the existing slender broach turning technology are described as follows:

[0035] Figure 1 Excessive pressure causes the inner concave center to appear:

[0036] When the cutting pressure applied to the slender broach is too large, the broach will produce excessive elastic deformation under the action of external force, and the middle part will be concave inward, resulting in the defect of concave in the machined workpiece. This deformation usually occurs in the middle part of the broach because it is farthest from the two supporting ends and has the smallest restraining force.

[0037] Figure 2 The pressure is too small and the car bulges out:

[0038] When the cutting pressure applied to the slender broach is too small, the broach will sag vertically under its own weight, and the middle part will bulge downward, resulting in a bulge-like defect on the surface of the workpiece. This is also a deformation caused by the lack of effective support in the middle.

[0039] Figure 3 Waist drum shape:

[0040] Figure 3 The waist-drum defect shown is caused by the uneven tangential torque on the slender broach during the turning process, which causes the broach to bend in an S shape. The middle of the broach bulges in the cutting direction, and the two ends are concave in the opposite direction. The final workpiece is in the shape of a waist drum with a thick middle and thin ends.

[0041] Figure 4 Bamboo shape:

[0042] Figure 4 It shows a periodic geometric defect, and the surface contour of the workpiece shows regular ups and downs, shaped like bamboo joints. It is speculated that it is caused by the periodic vibration of the slender broach during the turning process, or the feed is discontinuous and the speed is fast and slow. Vibration and feed error will leave periodic marks on the surface of the workpiece.

[0043] The above four illustrations depict various processing defects that are prone to occur in slender broaches under traditional turning methods. That is, the slender broaches are not rigid enough and are prone to elastic deformation under stress, so effective measures need to be taken to support and constrain them.

[0044] In view of this, the utility model provides a pin turning device for a broach, such as Figure 5-7 As shown:

[0045] Broach 1, follower rest 2, first elastic center 4 and external turning tool 7, wherein:

[0046] The broach 1 is a slender broach 1, placed horizontally, with a center hole at the left end of the broach 1 connected to the machine tool spindle; the center hole at the right end is supported by the first elastic top 4;

[0047] The tool rest 2 is used to support the broach 1;

[0048] The external cylindrical turning tool 7 is mounted on a turret and is used for turning at a designated position on the surface of the broach 1 .

[0049] Specifically, the external cylindrical turning tool 7 is mounted on the turret and is controlled by a program to turn at a specified position on the surface of the broach 1. When the turning tool cuts into the broach 1, it forms two pairs of radial support forces with the three cylindrical rods on the tool rest 2 to jointly limit the deformation of the broach 1.

[0050] like Figure 5 As shown, the tool rest 2 is provided with three supporting cylindrical rods, which are distributed in a triangular shape. When turning, the broach 1 is clamped in the middle of the channel formed by the three supporting cylindrical rods to support and position the broach 1. Specifically, the tool rest 2 is provided with three supporting cylindrical rods 3, which are distributed in a triangular shape. These three cylindrical rods are used to support and position the slender broach 1. When turning, the slender broach 1 is clamped in the middle of the channel formed by the three cylindrical rods 3. The cylindrical rods limit the movement of the broach 1 in the up-down and left-right directions, and only allow the broach 1 to rotate around its axis.

[0051] In addition, the tool rest 2 is designed with a curved surface, with different heights at both ends and a lower height in the middle, so as to keep the broach 1 as horizontal as possible when deformed by force, thereby reducing the additional bending moment caused by the height difference.

[0052] When the external turning tool 7 approaches and contacts the broach 1 on the tool rest 2, the turning tool and the three cylindrical rods 3 form two pairs of radial pressures on the broach 1, further limiting the radial movement of the broach 1. In this way, the tool rest 2 applies two pairs of radial supporting forces to the slender broach 1 through the three cylindrical rods, and cooperates with the external turning tool 7 to jointly limit the radial movement and deformation of the broach 1.

[0053] In addition, in one embodiment, the tool rest 2 is located in the middle right position of the broach 1, and serves as an intermediate support point. It is a trapezoidal structure with a circular through hole in the middle, and its size is larger than the diameter of the broach 1. The tool rest 2 is fixed on the machine tool guide rail through a base, and can move left and right along the guide rail to adjust the relative position with the broach 1. When the broach 1 is rotated and turned, the tool rest 2 remains stationary. In addition, the three cylindrical rods are in a triangular shape, supporting the broach 1 in the middle. The contact surface between the cylindrical rod and the broach 1 is very small, approximate to a line contact, so as to reduce the friction torque.

[0054] Optionally, the broach 1 turning equipment also includes a rotating body 5 and a second elastic tip 6, wherein the second elastic tip 6 is arranged at the left end of the broach 1, and a conical recess is arranged at the front end of the rotating body 5 for supporting the center hole of the broach 1, and the rotating body 5 and the second elastic tip 6 can slide relative to each other.

[0055] In addition, the rear end of the second elastic tip 6 is fixed on the tailstock, and the front end is a cylinder, which is inserted into the rear hole of the rotating body 5. The second elastic tip 6 is a standard machine tool center tip with a corresponding spring setting, and the rear end is fixed on the tailstock and cooperates with the rotating body 5. The front end is a small diameter cylinder, which is inserted into the rear hole of the rotating body 5. A certain gap is designed between the rotating body 5 and the second elastic tip 6. This gap allows the rotating body 5 to slide axially on the tip for a short distance, giving the slender broach 1 a certain axial degree of freedom.

[0056] In summary, the second elastic tip 6 is an improvement on the conventional tip by adding an elastic component to the conventional tip and cooperating with an axially slidable rotating body 5, allowing the slender broach 1 to produce axial micro displacement when subjected to force and releasing axial deformation. It cooperates with the tool rest 2 to suppress the deformation of the slender broach 1.

[0057] like Figure 6 As shown, the first elastic tip 4 includes a steel ball 8, a spring ring 9, a plug 10 and a screw 11, wherein the steel ball is located at one end of the elastic tip, the spring ring connects the steel ball and the first tip body, and when the steel ball abuts against the broach 1, the spring ring contracts; the plug is located above the steel ball and is fixed by the screw. The steel ball 8, spring ring 9, plug 10 and screw 11 and other components are used to adjust the pressure of the cylindrical rod 3 to adapt to broaches 1 of different sizes. When the slender broach 1 generates axial deformation force during turning, under the action of the elastic tip, the broach 1 can slide slightly along the axial direction, release part of the deformation stress, and automatically reset.

[0058] In addition, the first elastic tip 4 is installed on the tailstock of the machine tool to support one end of the slender broach 1. Different from the traditional tip, this tip has a certain elasticity and can allow the broach 1 to have a slight movement in the axial direction. Therefore, although the first elastic tip 4 allows axial displacement, it can still well constrain the slender broach 1 in the radial, circumferential and swinging directions to prevent shaking and deflection.

[0059] Compared with the prior art, the utility model has the following advantages:

[0060] In the utility model, the tool rest 2 has three supporting cylindrical rods. During turning, the broach 1 is clamped between the three cylindrical rods. The external cylindrical turning tool 7 works close to the tool rest 2, forming two pairs of radial pressures to limit the broach 1 from moving up and down and left and right, and can only rotate around the axis. The tailstock top adopts an elastic top, which can make the broach 1 stretch freely in the axial direction, effectively reduce cutting vibration and deformation of the broach 1, and will not damage the center hole.

[0061] Some exemplary embodiments of the utility model are described above, but those skilled in the art will appreciate that changes may be made to these exemplary embodiments without departing from the principles or spirit of the utility model, and the scope of the utility model is defined by the claims and their equivalents.

Claims

1. A broach turning device, characterized in that: include: Broach, follower rest, first elastic center and external turning tool, among which, The broach is a slender broach placed horizontally, with a center hole at the left end of the broach connected to the machine tool spindle; the center hole at the right end is supported by the first elastic center; The tool rest is used to support the broach; The external cylindrical turning tool is mounted on a turret and is used for turning at a designated position on the broach surface.

2. The broach turning equipment according to claim 1, characterized in that: The tool rest is provided with three supporting cylindrical rods distributed in a herringbone shape. When turning, the broach is clamped in the middle of a channel formed by the three supporting cylindrical rods to support and position the broach.

3. The broach turning equipment according to claim 1, characterized in that: The broach turning equipment also includes a rotating body and a second elastic tip, wherein the second elastic tip is arranged at the left end of the broach, and a conical recess is arranged at the front end of the rotating body for supporting the center hole of the broach, and the rotating body and the second elastic tip can slide relative to each other.

4. The broach turning equipment according to claim 3, characterized in that: The rear end of the second elastic tip is fixed on the tailstock, and the front end is a cylinder inserted into the rear hole of the rotating body.

5. The broach turning equipment according to claim 1, characterized in that: The first elastic top includes a steel ball, a spring ring, a plug and a screw, wherein the steel ball is located at one end of the elastic top, the spring ring connects the steel ball and the first top body, and when the steel ball abuts against the broach, the spring ring contracts; the plug is located above the steel ball and is fixed by the screw.

6. The broach turning equipment according to claim 1, characterized in that: The tool rest is a trapezoidal structure with a circular through hole in the middle, the size of which is larger than the diameter of the broach.

7. The broach turning device according to claim 6, characterized in that: The tool rest is fixed on the machine tool guide rail through a base and can move left and right along the guide rail to adjust the relative position with the broach. When the broach is rotating for turning, the tool rest remains stationary.

8. The broach turning device according to claim 6, characterized in that: When the broach generates axial deformation force during turning, under the action of the first elastic tip, the broach slides along the axial direction, releases part of the deformation stress, and automatically resets.

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