Reinforced flexible tapping shank

Abstract

This utility model discloses a reinforced flexible tapping tool holder, belonging to the field of machining tool technology. It includes a tool holder body, a tool holder core shell disposed at the front end of the tool holder body, a tool holder core passing through the tool holder core shell, and a tapping chuck connecting seat connected to the front end of the tool holder core. The tapping chuck connecting seat has at least one torque transmission keyway on its end face for connecting the tapping chuck, which engages with the torque transmission key block of the tapping chuck. The sidewall of the torque transmission keyway is set according to the wall thickness of the tapping chuck connecting seat, so as to disperse the shear stress generated by the torque through the wall thickness of the tapping chuck connecting seat. The beneficial effects of this utility model are: utilizing the wall thickness of the tapping chuck connecting seat itself to disperse the torque, avoiding local stress concentration leading to fracture, solving the problem of stress concentration and easy fracture in traditional connection structures, while ensuring circumferential torsional rigidity.

Description

Technical fields:

[0002] This utility model belongs to the field of machining tool technology, and more specifically relates to a reinforced flexible tapping tool holder. Background technology:

[0004] Tapping is a common machining operation used to create internal threads on workpieces. The tapping tool holder, as a key component connecting the machine tool spindle, tapping chuck, and tap, directly affects the quality of the tapping.

[0005] Existing tapping tool holders and tapping chucks mostly use a ring-shaped engagement mechanism, with torque transmitted through the ring-shaped contact surface. However, the torque fluctuates significantly during tapping, and this type of structure is prone to breakage at the connection point due to stress concentration. Utility model content:

[0007] To address the aforementioned problems and overcome the shortcomings of existing technologies, this utility model provides a reinforced flexible tapping tool holder;

[0008] The first technical problem to be solved was to increase the torsional strength at the connection between the tool holder and the collet to prevent breakage.

[0009] The specific technical solution of this utility model to solve the above-mentioned technical problems is as follows: the reinforced flexible tapping tool holder includes a tool holder body, a tool holder core shell disposed at the front end of the tool holder body, a tool holder core inserted into the tool holder core shell, and a tapping chuck connecting seat connected to the front end of the tool holder core.

[0010] The tapping chuck connector is used to connect the tapping chuck. At least one torque transmission keyway is provided on the end face of the tapping chuck to engage with the torque transmission key block of the tapping chuck.

[0011] The sidewall of the torque transmission keyway is set based on the wall thickness of the tapping chuck connector to disperse the shear stress generated by the torque through the wall thickness of the tapping chuck connector.

[0012] The tool holder body and the tool holder core are connected by at least one locating pin. The outer surface of the tool holder body is provided with an axial groove extending along its axis, and the outer surface of the tool holder core is provided with a locating pin mounting hole. One end of the locating pin is fixed in the locating pin mounting hole, and the other end is inserted into the axial groove to restrict the relative circumferential rotation of the tool holder body and the tool holder core, and to allow the tool holder core to slide axially along the axial groove.

[0013] Furthermore, the number of torque transmission keyways is two, and they are symmetrically distributed circumferentially along the end face of the tapping chuck connector.

[0014] Furthermore, the torque transmission keyway is a rectangular or trapezoidal groove distributed circumferentially along the end face of the tapping chuck connecting seat, and the torque transmission key block is a raised structure that matches the shape of the torque transmission keyway.

[0015] Furthermore, the tool holder body and the tool holder core are connected by two positioning pins. The two positioning pins are symmetrically distributed along the circumference of the tool holder body. The number of axial long grooves corresponds one-to-one with the number of positioning pins and is evenly arranged circumferentially on the outer surface of the tool holder body.

[0016] The number of mounting holes for the positioning pins corresponds one-to-one with the number of positioning pins and is evenly distributed circumferentially on the outer surface of the tool holder core.

[0017] Furthermore, the cross-section of the axial groove is U-shaped, rectangular, or dovetail-shaped, and the positioning pin is a cylindrical pin or a non-circular pin, the diameter of which is adapted to the width of the axial groove.

[0018] The beneficial effects of this utility model are:

[0019] One advantage of this invention is that the end face of the tapping chuck connector is provided with a torque transmission keyway that engages with the torque transmission key block of the tapping chuck. The torque is dispersed by the wall thickness of the tapping chuck connector itself, avoiding local stress concentration that could lead to breakage. This solves the problem of stress concentration and easy breakage in traditional connection structures, while ensuring circumferential torsional rigidity.

[0020] One advantage of this invention is that the tool holder body and the tool holder core are connected by a positioning pin. One end of the positioning pin is embedded in the positioning pin mounting hole, and the other end is inserted into the axial long groove. The cylindrical surface of the positioning pin is rigidly fitted with the side of the axial long groove, preventing the tool holder body and the tool holder core from rotating relative to each other and eliminating circumferential friction. Only the axial sliding friction of the tool holder core along the axial long groove is retained, reducing burr generation, ensuring that the tool holder core floats smoothly for a long time, and improving the stability of the axial compensation function. Attached image description:

[0022] Appendix Figure 1 This is an exploded view of the structure of this utility model;

[0023] Appendix Figure 2 This is a schematic diagram of the structure of this utility model;

[0024] Appendix Figure 3 This is a schematic diagram of the main structure of the knife handle of this utility model;

[0025] Appendix Figure 4 This is a schematic diagram of the tool holder core structure of this utility model; in the attached drawing:

[0026] 1. Tool holder body; 11. Axial long groove; 2. Tool holder core; 21. Locating pin mounting hole; 3. Tool holder core outer shell; 4. Tapping chuck connecting seat; 41. Torque transmission keyway; 5. Locating pin. Detailed implementation method:

[0028] In the description of this utility model, it should be understood that the terms "center," "upper," "lower," "left," "right," "rear," "lower left," "upper right," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this utility model. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0029] The specific embodiment of this utility model is as follows: A reinforced flexible tapping tool holder includes a tool holder body 1, a tool holder core 2 outer shell 3 disposed at the front end of the tool holder body 1, a tool holder core 2 passing through the tool holder core 2 outer shell 3, and a tapping chuck connecting seat 4 connected to the front end of the tool holder core 2. The tool holder core 2 and the tapping chuck connecting seat 4 are fixedly connected by welding or integrally formed.

[0030] The inventive point of this utility model is:

[0031] The tapping chuck connecting seat 4 is provided with at least one torque transmission keyway 41 on the end face of the tapping chuck, which closely matches the torque transmission key block of the tapping chuck. The torque transmission keyway 41 is a rectangular or trapezoidal groove distributed circumferentially along the end face of the tapping chuck connecting seat 4, and the torque transmission key block is a protrusion structure that matches the shape of the torque transmission keyway 41.

[0032] Preferably, there are two torque transmission keyways 41, which are symmetrically distributed circumferentially along the end face of the tapping chuck connecting seat 4.

[0033] The sidewall of the torque transmission keyway 41 is set according to the wall thickness of the tapping chuck connecting seat 4, so as to disperse the shear stress generated by the torque through the wall thickness of the tapping chuck connecting seat 4.

[0034] With this structure, a torque transmission keyway 41 is provided on the end face of the tapping chuck connecting seat 4, which is engaged with the torque transmission key block of the tapping chuck. The torque transmission is transferred from the traditional thread or annular contact surface to the wall thickness area of ​​the tapping chuck connecting seat 4. The torque is dispersed by the wall thickness of the tapping chuck connecting seat 4 itself, avoiding local stress concentration that leads to fracture. This solves the problem of "stress concentration and easy fracture" in traditional connection structures, while ensuring circumferential torsional rigidity.

[0035] The existing tool holder body 1 and tool holder core 2 are positioned by steel balls. The steel balls are in point contact with the axial groove 11, resulting in local stress concentration, rapid wear, and easy generation of metal chips. During the tapping process, the steel balls repeatedly rub against the axial groove 11, and the generated metal chips will accumulate in the axial groove 11. When the thickness of the metal chips exceeds the gap between the steel balls and the axial groove 11, the steel balls cannot slide freely, causing the tool holder core 2 to float and jam axially, or even completely jam, thus destroying the axial compensation function of tapping.

[0036] To solve the above-mentioned technical problems, as a preferred embodiment of this utility model,

[0037] The tool holder body 1 and the tool holder core 2 are connected by at least one locating pin 5. The outer surface of the tool holder body 1 is provided with an axial groove 11 extending along its axis. The outer surface of the tool holder core 2 is provided with a locating pin 5 mounting hole 21. One end of the locating pin 5 is interference-fitted with the locating pin 5 mounting hole 21, and the other end is inserted into the axial groove 11. The interference-fitting of the locating pin 5 with the locating pin 5 mounting hole 21 restricts the relative circumferential rotation of the tool holder body 1 and the tool holder core 2, and allows the tool holder core 2 to slide axially along the axial groove 11, thereby achieving axial floating compensation.

[0038] Preferably, the cross-section of the axial groove 11 is U-shaped, rectangular, or dovetail-shaped, and the positioning pin 5 is a cylindrical pin or a non-circular pin, the diameter of which is adapted to the width of the axial groove 11.

[0039] Preferably, the handle body 1 and the handle core 2 are connected by two positioning pins 5. The two positioning pins 5 are symmetrically distributed around the circumference of the handle body 1. The number of axial long grooves 11 corresponds one-to-one with the number of positioning pins 5 and is evenly arranged around the outer surface of the handle body 1.

[0040] The number of mounting holes 21 for the positioning pins 5 corresponds one-to-one with the number of positioning pins 5 and are evenly arranged circumferentially on the outer surface of the tool holder core 2.

[0041] With this structure, one end of the positioning pin 5 is embedded in the positioning pin 5 mounting hole 21, and the other end is inserted into the axial long groove 11. The surface contact between the positioning pin 5 and the axial long groove 11 replaces the point contact of the steel ball. Compared with the point contact of the steel ball, the contact area is increased several times, the stress is more evenly distributed, and the wear rate is significantly reduced.

[0042] Furthermore, the cylindrical surface of the positioning pin 5 is rigidly fitted to the side of the axial groove 11, preventing the tool holder body 1 and the tool holder core 2 from rotating relative to each other and eliminating circumferential friction; only the axial sliding friction of the tool holder core 2 along the axial groove 11 is retained, reducing the generation of burrs, ensuring that the tool holder core 2 floats smoothly for a long time, and improving the stability of the axial compensation function.

[0043] It should be noted that this utility model is a reinforced flexible tapping tool holder. In specific operation...

[0044] The tool holder body 1 is connected to the machine tool spindle. After the machine tool spindle starts, it transmits rotational power to the tool holder body 1. One end of the positioning pin 5 is embedded in the positioning pin 5 mounting hole 21, and the other end is inserted into the axial long groove 11. The cylindrical surface of the positioning pin 5 is rigidly fitted with the side of the axial long groove 11, preventing the tool holder body 1 and the tool holder core 2 from rotating relative to each other and eliminating circumferential friction. Only the axial sliding friction of the tool holder core 2 along the axial long groove 11 is retained, reducing burr generation and ensuring that the tool holder core 2 floats smoothly for a long time, thus improving the stability of the axial compensation function. Thus, the torque is transmitted from the tool holder body 1 to the tool holder core 2. The tool holder core 2 is fixedly connected to the tapping chuck connecting seat 4, and the torque continues to be transmitted to the tapping chuck connecting seat 4. The torque transmission keyway 41 opened on the front end face of the tapping chuck connecting seat 4 is tightly fitted with the torque transmission key block on the tapping chuck. The torque transmission keyway 41 contacts the side of the key block to transmit the torque to the tapping chuck, ultimately driving the tap to rotate for tapping.

[0045] In this process, the design of the torque transmission keyway 41 utilizes the wall thickness of the tapping chuck connector 4 itself to bear the torque. Compared with the traditional connection method, it can distribute the torque to the entire tapping chuck connector 4, avoiding the risk of fracture caused by local stress concentration.

[0046] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A reinforced flexible tapping tool holder, comprising a tool holder body (1), a tool holder core (2) housing (3) disposed at the front end of the tool holder body (1), a tool holder core (2) passing through the housing (3) of the tool holder core (2), and a tapping chuck connecting seat (4) connected to the front end of the tool holder core (2); characterized in that: The tapping chuck connector (4) is provided with at least one torque transmission keyway (41) on the end face of the tapping chuck, which is engaged with the torque transmission key block of the tapping chuck. The side wall of the torque transmission keyway (41) is set according to the wall thickness of the tapping chuck connector (4) so ​​as to disperse the shear stress generated by the torque through the wall thickness of the tapping chuck connector (4).

2. The reinforced flexible tapping tool holder according to claim 1, characterized in that... The number of torque transmission keyways (41) is two, and they are symmetrically distributed circumferentially along the end face of the tapping chuck connector (4).

3. The reinforced flexible tapping tool holder according to claim 2, characterized in that... The torque transmission keyway (41) is a rectangular or trapezoidal groove distributed circumferentially along the end face of the tapping chuck connecting seat (4), and the torque transmission key block is a protruding structure that matches the shape of the torque transmission keyway (41).

4. The reinforced flexible tapping tool holder according to claim 1, characterized in that... The handle body (1) and the handle core (2) are connected by at least one positioning pin (5). The outer surface of the handle body (1) is provided with an axial groove (11) extending along its axis. The outer surface of the handle core (2) is provided with a positioning pin (5) mounting hole (21). One end of the positioning pin (5) is interference-fitted with the positioning pin (5) mounting hole (21), and the other end is inserted into the axial groove (11). The positioning pin (5) is interference-fitted with the positioning pin (5) mounting hole (21) to restrict the relative circumferential rotation of the handle body (1) and the handle core (2), and to allow the handle core (2) to slide axially along the axial groove (11).

5. A reinforced flexible tapping tool holder according to claim 4, characterized in that... The handle body (1) and the handle core (2) are connected by two positioning pins (5). The two positioning pins (5) are symmetrically distributed around the handle body (1). The number of axial long grooves (11) corresponds one-to-one with the number of positioning pins (5) and is evenly arranged around the outer surface of the handle body (1). The number of mounting holes (21) of the positioning pins (5) corresponds one-to-one with the number of positioning pins (5) and is evenly arranged circumferentially on the outer surface of the tool holder core (2).

6. A reinforced flexible tapping tool holder according to claim 5, characterized in that... The cross-section of the axial long groove (11) is U-shaped, rectangular or dovetail-shaped, and the positioning pin (5) is a cylindrical pin or a special-shaped pin, the diameter of which is adapted to the width of the axial long groove (11).

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