CN109158936B - Tool changing mechanism - Google Patents

Abstract

The invention relates to a tool changing mechanism, which comprises a spindle mechanism and at least two groups of tool changing components for switching tools for the spindle mechanism, wherein the spindle mechanism comprises a spindle bracket and a spindle, the lower part of the spindle extends out of the spindle bracket, the bottom of the spindle is provided with a clamping opening for clamping the tools, the clamping opening and the tools are kept on the same axis, the tool changing components are uniformly distributed along the circumferential direction of the outer side wall of the spindle bracket, and in the state that the tool changing components are used for completing tool changing and retracting, the components of the tool changing components are positioned at the outer side of the spindle bracket so as to avoid interference with the spindle. In the state that the tool changing assembly is completed to change the tool, all parts of the tool changing assembly are positioned on the outer side of the main shaft frame and far away from the main shaft, so that interference with the main shaft and a tool clamped by the main shaft is avoided; the clamping opening of the main shaft and the cutter are kept on the same axis, and the main shaft can be always positioned right above a hole to be machined, so that the problem of machining deviation caused by misalignment of the cutter and the hole is avoided.

Description

A tool changing mechanism

Technical Field

The invention belongs to the technical field of mechanical processing, and in particular relates to a tool changing mechanism.

Background technique

With the shortage of labor and the increase in labor costs, processing companies have adopted the method of replacing people with machines to cope with the situation of labor difficulties, so that factories can achieve automated production, improve product processing quality, speed up product production efficiency and reduce product production costs. Among them, threaded connection is the main connection method for industrial products, and drilling and tapping on product parts account for a large proportion in the product production process. For example, the panel on the smart lock needs to have several mounting holes on the panel. In order to improve the processing accuracy and efficiency of the mounting holes, drilling and tapping machines came into being. In addition, the drilling and tapping machine is generally equipped with a tool magazine for tool change, and different tools are used to drill and tap the mounting holes or process holes of different diameters.

As shown in the utility model patent "Drilling and tapping machine with a gear-type tool magazine" disclosed in Patent No. ZL201620413660.7 (Announcement No. CN205733799U), the drilling and tapping machine realizes the tool changing function by rotating the tool magazine through gear transmission, but the gear transmission can easily cause the tool magazine to not rotate in place, resulting in the tool and the hole to be processed cannot be fully aligned, thereby affecting the processing of the workpiece.

Or as shown in the invention patent with patent number ZL201710198612.X (publication number CN106826335A) disclosed in "A double-link tool changing device", it includes several groups of tool changing components, spindles, and bases. The spindles are arranged in the middle of the base and can move up and down. Several groups of tool changing components are arranged around the spindles. Each group of tool changing components includes a driving device, a tool holder, a double link, and a fixed seat. One end of the double link is movably connected to the fixed seat fixed at the bottom of the base, and the other end of the double link is connected to the horizontally arranged tool holder. The double link can rotate around the fixed seat under the action of the driving device, and the tool holder remains horizontal during the movement of the double link. Each group of tool changing components is independently controlled and operated, and the tool handle under the tool changing component of any group can be selected to switch with the tool handle under the spindle to achieve tool changing.

Since the position of the spindle is fixed, the position of the tool mounted on the spindle is also fixed. Before processing, the position of the spindle can be adjusted to align with the hole to be processed, so there will be no problem of inaccurate tool positioning and failure to align with the hole position. However, when one set of tool change assemblies is folded, it is still located on one side of the spindle and close to the spindle. This can easily cause the other set of tool change assemblies to interfere with the spindle or the previous set of tool change assemblies when the tool card has a large movement stroke, and the structure is not compact enough; in addition, when the tool change assembly is folded, its position is also relatively low, and the tool card and the tool clamped by the tool card are always located below the base. In this way, when processing the workpiece, if the surface of the workpiece is uneven, the higher position of the workpiece is easy to interfere with the tool card or the tool clamped by the tool card.

Summary of the invention

The technical problem to be solved by the present invention is to provide a tool changing mechanism in which a tool can always be aligned with a hole to be processed for processing and a folded tool changing assembly will not interfere with other components in view of the current status of the prior art.

The technical solution adopted by the present invention to solve the above-mentioned technical problems is: a tool changing mechanism, including a spindle mechanism and at least two groups of tool changing assemblies for switching tools for the spindle mechanism, the spindle mechanism including a spindle frame and a spindle, the spindle frame extends from the lower part of the spindle, and the bottom of the spindle has a clamping port for clamping the tool, characterized in that: the clamping port and the tool are maintained on the same axis, and each tool changing assembly is evenly distributed circumferentially along the outer wall of the spindle frame. When the tool changing assembly completes the tool change and is retracted, each component of the tool changing assembly is located on the outside of the spindle frame to avoid interference with the spindle.

The tool changing mechanism can have various structural forms. Preferably, each tool changing assembly includes:

A first driving mechanism comprises a first driving member and a first push rod driven by the first driving member to move up and down, wherein the first driving member is arranged on the outer side wall of the main shaft frame;

The second driving mechanism comprises a second driving member and a second push rod driven by the second driving member to move up and down, wherein the second driving member is drivingly connected to the power output end of the first push rod;

A clamping mechanism for clamping a tool, wherein the first end of the clamping mechanism is rotatably connected to the output end of a first push rod, the second end of the clamping mechanism is provided with a clamping portion for clamping the tool, the middle portion of the clamping mechanism is rotatably connected to the first end of a connecting member, and the second end of the connecting member is rotatably connected to the power output end of a second push rod.

The tool changing mechanism has a simple structure, and the cooperation of various components makes the tool changing action fast and reliable. When the tool changing mechanism is not working, the first push rod, the second push rod and the clamping mechanism can be completely retracted and kept away from the electric spindle to prevent interference with the electric spindle and the tool on the electric spindle.

To further ensure that the tool changing mechanism is away from the electric spindle when being retracted, the second driving member is located outside the first driving member.

To prevent the clamping mechanism or the tool on the clamping mechanism from interfering with the workpiece due to the lower position when the tool changing mechanism is folded, the bottom surfaces of the first driving member and the second driving member are higher than the bottom surface of the spindle frame. If the surface of the workpiece is uneven, the higher part is very likely to interfere with the clamping mechanism or the tool on the clamping mechanism.

In order to facilitate the driving connection between the second driving member and the power output end of the first push rod, the second driving member is connected to the output end of the first push rod through a connecting frame, and the first end of the clamping mechanism is hinged to the connecting frame. The setting of the connecting frame not only facilitates the assembly of the first driving member, the second driving member, and the clamping mechanism, but also allows the second driving member to run smoothly when driven by the first push rod. If there is no connecting frame, the second driving member is set at the lower end of the first push rod. When the tool changing mechanism is retracted, the position of the tool clamped by the clamping mechanism will also be relatively low, which is easy to interfere with the workpiece when processing the workpiece.

In order to further improve the running stability of the second driving member when it is driven by the first push rod, the connecting frame and the first driving member are slidably connected by a slide rail structure. The setting of the slide rail structure not only makes the second driving member run smoothly, but also guides its running trajectory, because if the second driving member has a running deviation, it is very likely that the clamping mechanism cannot accurately cooperate with the electric spindle to change the tool.

In order to make the clamping mechanism away from the spindle when the tool changing mechanism is folded to avoid interference with the tool on the spindle, preferably, the clamping mechanism includes a rear section, a front section and a middle section connecting the rear section and the front section, the rear section is rotatably connected to the first push rod, the connection between the front section and the middle section is rotatably connected to the first end of the connecting member, the clamping part is arranged at the end of the front section, and the angle between the rear section and the middle section is an obtuse angle, and the angle between the middle section and the front section is an obtuse angle. The clamping mechanism has a simple structure and is easy to manufacture. Of course, the clamping mechanism can also be other structures as long as it does not interfere with the electric spindle when folded.

To facilitate clamping the tool, the clamping portion includes a recessed portion opened at the end of the front section, and clamping members for positioning the tool in the groove are provided on the opposite side walls of the recessed portion.

In order to reduce the size of the tool, the head of the tool is in the shape of a truncated cone with a small upper portion and a large lower portion, so that the upper portion of the tool can be directly clamped by the spindle without the need to provide a conical tool handle.

Compared with the prior art, the advantages of the present invention are as follows: 1. When the tool changing assembly of the present invention is in the state of completing tool changing and being put away, all components of the tool changing assembly are located on the outside of the spindle frame and away from the spindle, so that there will be no interference with the spindle and the tool clamped by the spindle; and the clamping port of the spindle and the tool are kept on the same axis, and the spindle can always be located directly above the hole to be processed, so that there will be no problem of processing deviation caused by misalignment between the tool and the hole; 2. The bottom surfaces of the first driving member and the second driving member of the tool changing mechanism are both higher than the bottom surface of the spindle frame, so that when the tool changing assembly is in the state of completing tool changing and being put away, all components of the tool changing mechanism and the tool on the tool changing mechanism can be in a higher position relative to the spindle, so that when the tool on the spindle processes a workpiece, the tool changing mechanism and the tool thereon will not interfere with the workpiece.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic structural diagram of an embodiment of the present invention;

FIG2 is a schematic diagram of the structure of FIG1 in another direction;

FIG3 is a schematic structural diagram of one set of tool changing assemblies in FIG1 ;

FIG4 is a schematic diagram of the structure of the tool in FIG3 ;

FIG5 is a schematic structural diagram of the clamping mechanism in FIG3 ;

FIG6 is a schematic structural diagram of the first driving member in FIG3 ;

FIG. 7 is a schematic structural diagram of the connecting frame in FIG. 3 .

Detailed ways

The present invention is further described in detail below with reference to the accompanying drawings.

As shown in FIGS. 1 to 7 , the tool changing mechanism of the preferred embodiment includes a spindle mechanism 1 and at least two sets of tool changing assemblies 2 for switching the tool 3 for the spindle mechanism 1. The spindle mechanism 1 includes a spindle frame 11 and a spindle 12. The lower part of the spindle 12 extends out of the spindle frame 11, and the bottom of the spindle 12 has a clamping opening 121 for clamping the tool 3. As shown in FIGS. 1 and 2 , in the present embodiment, there are three sets of tool changing assemblies 2, and each tool changing assembly 2 is evenly distributed along the circumferential direction of the outer wall of the spindle frame 11. When the tool changing assembly 2 completes the tool changing and is retracted, each component of the tool changing assembly 2 is located outside the spindle frame 11 to stay away from the spindle 12 to avoid interference with the spindle 12 or the tool 3 on the spindle 12.

As shown in Figure 3, each tool changing assembly 2 includes a first driving mechanism 21, a second driving mechanism 22 and a clamping mechanism 23 for clamping the tool 3. The first driving mechanism 21 includes a first driving member 211 and a first push rod 212 driven by the first driving member 211 to move up and down. The first driving member 211 is arranged on the outer wall of the main shaft frame 11; the second driving mechanism 22 includes a second driving member 221 and a second push rod 222 driven by the second driving member 221 to move up and down. The second driving member 221 is located on the outer side of the first driving member 211 and a connecting frame 4 is provided between the second driving member 211 and the first driving member 211, and the bottom surfaces of the first driving member 211 and the second driving member 221 are both higher than the bottom surface of the main shaft frame 11.

In this embodiment, the first driving member 211 and the second driving member 221 may both be a cylinder or a hydraulic cylinder.

The connecting frame 4 is fixedly connected to the second driving member 221, and is slidably matched with the first driving member 211 through a slide rail structure, and the output end of the first push rod 212 is arranged on the connecting member 24. As shown in Figures 6 and 7, the slide rail structure includes a slide groove 213 arranged on the first driving member 211 and a guide rail 41 arranged on the connecting frame 4, and the guide rail 41 is placed in the slide groove 213 and can move up and down relative to the slide groove 213.

As shown in Figure 5, the clamping mechanism 23 includes a rear section 232, a front section 233 and a middle section 234 connecting the rear section 232 and the front section 233, wherein the rear section 232 (i.e. the first end of the clamping mechanism 23) is rotatably connected to the hinge portion 42 on the connecting frame 4, the connection between the front section 233 and the middle section 234 (i.e. the middle part of the clamping mechanism 23) is rotatably connected to the first end of the connecting member 24, the second end of the connecting member 24 is rotatably connected to the second push rod 222, and a clamping portion 231 is provided at the end of the front section 233 (i.e. the second end of the clamping mechanism 23), the angle between the rear section 232 and the middle section 234 is an obtuse angle, and the angle between the middle section 234 and the front section 233 is an obtuse angle.

The clamping portion 231 includes a recessed portion 235 opened at the end of the front section 233. The opposite side walls of the recessed portion 235 are provided with clamping members 236 for positioning the tool 3 in the recessed portion 235. The clamping members 236 are pressed by the tool 3 and can move relative to the recessed portion 235 to clamp or release the tool 3. In other words, when the tool 3 needs to be installed, the two clamping members 236 are relatively separated to place the tool 3 in the recessed portion 235, and then the clamping members 236 are elastically moved together to clamp the tool 3.

In addition, as shown in FIG4 , the head of the tool 3 is in the shape of a truncated cone with a small top and a large bottom, so that the upper part of the tool 3 can be directly clamped by the spindle 12 without the need for a conical tool holder. According to the characteristics of the workpiece, the clamping portion 231 of each tool changing assembly 2 can be installed with a chamfering tool 3, a tapping tool 3, a drilling tool 3 or tools 3 of different diameters, etc. The tool 3 can be quickly and arbitrarily replaced at different processing stages of the workpiece.

The second driving mechanism 22 can move synchronously with the first driving mechanism 21, the clamping mechanism 23 can rotate relative to the first push rod 212, the connecting member 24 can rotate relative to the second push rod 222, and the connecting member 24 is rotationally connected to the clamping mechanism 23, that is, the connecting member 24 and the clamping mechanism 23 are combined into a crank connecting rod mechanism.

When the first push rod 212 remains stationary, the first push rod 212 and the clamping mechanism 23 can be considered to be relatively fixed. At this time, the second push rod 222 can drive the connecting member 24 to move up and down, so that the clamping mechanism 23 can rotate around the hinge part 42 on the connecting frame 4, thereby controlling the position of the tool 3.

The working process of the tool changing assembly 2 of this embodiment is as follows: when the tool 3 reaches the position shown in FIG. 1 (the tool 3 clamped by the tool changing assembly 2 on the left, the tool changing assembly 2 is in the open state), the first push rod 212 retracts to drive the second driving mechanism 22, the connecting member 24, and the clamping mechanism 23 upward as a whole, so that the tool 3 rises vertically to a position where it can be clamped by the clamping opening 121 of the electric spindle 12. After the tool 3 is clamped, the first driving mechanism 21 does not move, the second push rod 222 retracts, and the clamping mechanism 23 is moved away, completing the entire tool installation process.

When changing the tool, the process is opposite to the above process. The first push rod 212 does not move, the second push rod 222 extends, driving the clamping mechanism 23 to grab the tool 3, the clamping port 121 of the electric spindle 12 releases the tool 3, and then the first push rod 212 moves downward to pull out the tool 3. Finally, after the second push rod 222 retracts, the first push rod 212 retracts, and its final position is shown as the tool changing assembly on the right side of Figure 1 (the tool changing assembly is in the retracted state).

Claims (3)

1. A tool changing mechanism, comprising a spindle mechanism (1) and at least two sets of tool changing assemblies (2) for switching tools (3) for the spindle mechanism (1), the spindle mechanism (1) comprising a spindle frame (11) and a spindle (12), the spindle (12) extending from the spindle frame (11) at the bottom, and having a clamping opening (121) for clamping the tool (3) at the bottom of the spindle (12), characterized in that: the clamping opening (121) and the tool (3) are kept on the same axis, and each tool changing assembly (2) is evenly distributed along the circumference of the outer wall of the spindle frame (11), and when the tool changing assembly (2) completes the tool changing and is retracted, each component of the tool changing assembly (2) is located on the outer side of the spindle frame (11) to avoid interference with the spindle (12); Each tool changing assembly (2) includes A first driving mechanism (21) comprises a first driving member (211) and a first push rod (212) driven by the first driving member (211) to move up and down, wherein the first driving member (211) is arranged on an outer side wall of the main shaft frame (11); A second driving mechanism (22), comprising a second driving member (221) and a second push rod (222) driven by the second driving member (221) to move up and down, wherein the second driving member (221) is drivingly connected to a power output end of the first push rod (212); A clamping mechanism (23), wherein the first end of the clamping mechanism (23) is rotatably connected to the output end of the first push rod (212), the second end of the clamping mechanism (23) is provided with a clamping portion (231) for clamping the tool (3), the middle portion of the clamping mechanism (23) is rotatably connected to the first end of a connecting member (24), the second end of the connecting member (24) is rotatably connected to the power output end of the second push rod (222); the second driving member (221) is located outside the first driving member (211); the bottom surfaces of the first driving member (211) and the second driving member (221) are both higher than the bottom surface of the spindle frame (11); the second driving member (221) is connected to the output end of the first push rod (212) through a connecting frame (4), and the first end of the clamping mechanism (23) is hinged to the connecting frame (4); The connecting frame (4) and the first driving member (211) are slidably connected via a slide rail structure; The clamping mechanism (23) comprises a rear section (232), a front section (233) and a middle section (234) connecting the rear section (232) and the front section (233); the rear section (232) is rotatably connected to the first push rod (212); the connection between the front section (233) and the middle section (234) is rotatably connected to the first end of the connecting member (24); the clamping portion (231) is arranged at the end of the front section (233); the angle between the rear section (232) and the middle section (234) is an obtuse angle; and the angle between the middle section (234) and the front section (233) is an obtuse angle. 2. The tool changing mechanism according to claim 1 is characterized in that: the clamping portion (231) includes a recessed portion (235) opened at the end of the front section (233), and clamping members (236) for positioning the tool (3) in the recessed portion (235) are provided on opposite side walls of the recessed portion (235). 3. The tool changing mechanism according to claim 1 is characterized in that the head of the tool (3) is in the shape of a truncated cone that is smaller at the top and larger at the bottom.