TW202035037A - Milling chuck having robustly combined pull stub capable of reducing milling chuck runout during rotation to enhance machining precision - Google Patents

Abstract

A milling chuck having robustly combined pull stub includes a milling chuck body and a pull stub that are screwed together. The connecting portion of the milling chuck body includes an inner thread portion and a linear portion. The pull stub includes a head portion, a stopping portion, and an outer thread portion. The stopping portion includes a flange and an extension portion. The extension portion is in clearance fit with the linear portion and configured with a sealing member for sealing the clearance. The outer thread portion is screwed with the inner thread portion and includes a first thread section and a second thread section, wherein the first thread section is located at one end far away from the head portion of the pull stub, and the machining precision of the second thread section is better than that of the first thread section.

Description

A shank with a firmly combined slider

The present invention relates to a tool bar of a processing machine, in particular to a tool bar with a slider.

Please refer to FIGS. 6 and 7 in conjunction. The existing tool bar 90 mainly uses a screw lock to connect the slider 92 at the top of the tool bar body 91 and the clamping device 81 in the main shaft 80 of the processing machine to clamp and secure the tool bar. 90 can be driven by the spindle 80 to rotate for processing operations.

The existing slider 92 mainly includes a head 921, a flange 922, and an external threaded portion 923. The head 921 and the external threaded portion 923 are respectively provided at opposite ends of the slider 92. The flange 922 has a diameter The head 921 and the external threaded portion 923 are formed between the head 921 and the external threaded portion 923; the external threaded portion 923 of the slider 92 is screwed to the internal threaded portion 911 of the shank body 91, and the flange 922 is pressed against It stops at the end surface of the arbor body 91 to position the connection position of the arbor body 91 and the slider 92 so that the head 921 protrudes from the end surface of the arbor body 91.

Existing thread standards can be divided into metric thread standards and inch thread standards. The fit levels are roughly divided into loose fit, intermediate fit and precision fit. The machining accuracy levels of the external thread of the inch thread standard are divided into 1A, 2A and 3A. The machining accuracy grades of internal threads are divided into 1B, 2B and 3B. The higher the grade number, the tighter the fit. The machining accuracy grades of the internal and external threads of the toolholder body 91 and the slider 92 are usually 2A and 2B. The middle-level thread fit; the tolerance position of the external thread of the metric thread standard is divided into e, g, h, and the tolerance position of the internal thread is divided into G, H, where the basic deviation of H and h is zero, and the basic deviation of G is positive , The basic deviation of e and g are negative values, and the precision grade is represented by a number. The higher the number, the lower the precision grade. The processing precision grade of the toolholder body 91 and the slider 92 is usually 6H/6g intermediate thread matching.

However, the existing connection between the shank body 91 and the slider 92 only relies on the threaded connection of the internal and external threaded parts 911 and 923, and is an intermediate fit, which is affected by the allowable internal and external thread clearance. If the tightening torque between 91 and the slider 92 is too small, the connection between the arbor body 91 and the slider 92 is not stable, and it is easy to loosen and shake; if the tightening torque between the arbor body 91 and the slider 92 is too large, The connection between the slider 92 and the tool holder body 91 will be affected by the thread gap, and the tie rod 92 and the tool holder body 91 will be connected eccentrically, which will cause the tool holder 90 to easily deflect when rotating, and affect the machining accuracy of the processing machine, which needs to be improved .

In view of this, the main purpose of the present invention is to provide a tool bar with a more stable assembly between the slider and the tool bar body, reducing the deflection of the tool bar when rotating, so as to improve the machining accuracy of the processing machine.

In order to achieve the above-mentioned object, the present invention proposes a cutter bar with a firmly combined slider, which includes A shank body, which contains One end face; and A connecting part is formed in the main body of the shank in the axial direction, and an opening is formed on the end surface. The connecting part includes an internal threaded part and a straight part having the same axis. The internal threaded part is arranged on the side away from the end surface, And the processing accuracy specification of the internal thread part is in accordance with a standard thread specification, and the straight part is formed between the internal thread part and the end surface; and A slider is screw-connected to the main body of the arbor, and includes a head, a stop portion, and an external threaded portion. The head and the external threaded portion are respectively provided at opposite ends of the slider. The abutting part is formed between the head and the external thread part; wherein The stop includes A flange protruding radially from the slider, and one end of the flange away from the head abuts against the end surface of the arbor body; An extension part inserted in the connecting part of the shank body and clearance fit with the straight part; A ring groove radially recessed in the extension part; and A sealing element arranged in the ring groove and sealing the gap between the extension part of the slider and the straight part of the shank body; and The external thread part is screwed and connected with the internal thread part of the shank body, which includes A first threaded section is located at an end away from the head, the machining accuracy specification of the first threaded section is in accordance with the standard thread specification, and the threaded fit between the first threaded section and the internal threaded portion is the standard thread Intermediate coordination of the specifications; A second threaded section located at an end close to the head, the machining accuracy specification of the second threaded section is in accordance with the standard thread specification, and the machining accuracy grade is better than that of the first threaded section; and A spaced groove is radially recessed between the first threaded section and the second threaded section.

With the above-mentioned technical features, the seal can eliminate the gap between the slider and the body of the shank, increase the stability of the combination, absorb vibration, and have a water-stop effect; and the two-stage processing accuracy of the external thread of the slider It can make the screwing process of the slider and the arbor body more tightly, and reduce the deflection error of the connection position during the process of locking, and can reduce the tightening torque between the arbor body and the slider. The eccentricity generated by the tool bar reduces the deflection and vibration of the tool bar during high-speed rotation, and improves the machining accuracy and service life of the tool bar.

Please refer to FIGS. 1 and 2. The arbor with a firmly combined slider of the present invention includes a arbor body 10 and a slider 20; the arbor body 10 includes an end surface 11 and a connecting portion 13; The connecting portion 13 is axially formed in the shank body 10, and an opening is formed on the end surface 11, which includes an internal threaded portion 131 and a straight portion 133 having the same axis; the internal threaded portion 131 is located away from the end surface One side of 11 is provided with an internal thread. The processing accuracy specification of the internal thread portion 131 is in accordance with the specifications of the British standard thread, and the processing accuracy grade is 2B of the British standard internal thread; the straight portion 133 is formed on the internal thread 131 and the end surface 11, and the straight portion 133 is a circular groove coaxial with the internal thread portion 131. Preferably, a groove 132 is provided between the straight portion 133 and the internal thread portion 131. The groove 132 is radially recessed in the tool bar body 10 to facilitate processing and assembly.

The slider 20 is threadedly connected to the arbor body 10, and includes a head 21, a stop portion 22, an external thread portion 23, and a through hole 24; the head 21 and the external thread portion 23 are respectively Formed at opposite ends of the slider 20, the abutting portion 22 is formed between the head 21 and the external thread portion 23, and the through hole 24 axially penetrates the slider 20 to facilitate installation in A processing machine with a built-in cutting fluid system, and the cutting fluid can enter the tool holder body 10 through the through hole 24 from the processing machine, and cool and lubricate the tool; please refer to Figure 5, the slider 20A may not be provided The through hole 24 is suitable for processing machines without a cutting fluid system.

Please refer to FIGS. 2 and 3 together. The abutting portion 22 includes a flange 221, an extension portion 222, an annular groove 223 and a sealing member 25. The flange 221 radially protrudes from the slider 20, and its end away from the head 21 abuts against the end surface 11 of the cutter bar body 10. The extension 222 is a cylinder, extends axially from one end of the flange 221 away from the head 21, and is inserted into the connecting portion 13 of the shank body 10. The outer diameter of the extension 222 is slightly smaller than The inner diameter of the straight portion 133 forms a clearance fit with the straight portion 133. The ring groove 223 is radially recessed in the extension portion 222; the sealing member 25 is an O-ring elastic body, which is provided in the ring groove 223, and a part of the surface of the sealing member 25 is slightly convex in the natural state At the extension portion 222, it interferes with the straight portion 133, and closes the gap between the extension portion 222 and the straight portion 133; by providing the abutting portion 22, the cutter body 10 and the tension The stability of the connection of the head 20 can absorb vibration and avoid shaking, and can prevent the cutting fluid from overflowing from the gap between the tool bar body 10 and the slider 20 to achieve a water stop effect.

2 and 4, the external thread portion 23 is threadedly connected with the internal thread portion 131, which includes a first threaded section 231, a second threaded section 232 and a separating groove 233; A threaded section 231 is located at an end away from the head 21, and the machining accuracy specification of the first threaded section 231 is in accordance with the specifications of the British standard thread, and its machining accuracy is level 2A of the British standard external thread, so that the first The threaded fit between the threaded section 231 and the internal threaded portion 131 is an intermediate fit in the British thread standard; the second threaded section 232 is located at an end close to the head 21, and the processing accuracy grade of the second threaded section 232 is the British standard The external thread is 3A, so that the processing accuracy of the second threaded section 232 is better than that of the first threaded section 231, and the thread gap T2 between the second threaded section 232 and the internal threaded portion 131 is smaller than the first The thread gap T1 between a threaded section 231 and the internal threaded portion 131; the separation groove 233 is radially recessed between the first threaded section 231 and the second threaded section 232 to facilitate the external threaded portion 23 Different precision thread processing.

Take the internal and external threads with an inch standard thread outer diameter of 5/8 inches as an example. When the machining accuracy of the internal thread is 2B, the maximum allowable size of the thread cross-section is 0.5732 inches, and the tolerance value is 0.0072 inches. When the machining accuracy level of the external thread is 2A, the minimum allowable thread cut diameter is 0.5588 inches, and the tolerance value is 0.0055 inches. When the machining accuracy of the external thread is 3A, the minimum allowable thread cut diameter is 0.5619 inches. Inch, the tolerance value is 0.0041 inches, so the maximum thread clearance T1 at the thread cut diameter of the internal thread portion 131 and the first thread segment 231 is 0.0144 inches, the minimum thread clearance is 0.0017 inches, and the tolerance value is 0.0127 inches , The maximum thread gap T2 at the thread cut diameter of the internal thread portion 131 and the second thread segment 232 is 0.0113 inches, the minimum thread gap is 0 inches, and the tolerance value is 0.0113 inches, so that the second thread segment 232 and the internal The threaded part 131 is tightly screwed, and the screwing process of the slider 20 and the arbor body 10 is tightened as the locking is performed, and the deflection of the connection position is automatically reduced during the locking process, thereby reducing the arbor body The eccentricity generated when the tightening torque between 10 and the slider 20 is too large, thereby reducing the deflection of the tool bar during high-speed rotation, improving the machining accuracy of the tool bar, and increasing the service life of the tool bar.

Preferably, the processing tolerance of the second threaded section 232, in addition to the tolerance specified in accordance with the 3A level, further adds a positive clearance tolerance to further reduce the second threaded section 232 and the inner The thread gap between the threaded parts 131 makes the second threaded section 232 and the internal threaded part 131 more tightly locked, and reduces the eccentricity during connection, as in the above-mentioned standard inch thread outer diameter 5/8 inch thread embodiment The tolerance range of the compensation gap can be set from +0.003937 inches (about 0.1 mm) to +0.002362 inches (about 0.06 mm), so that the second thread section 232 and the internal thread portion 131 have the largest cross-sectional diameter. The gap is reduced to 0.0074 inches (about 0.187 mm).

The above-mentioned internal thread portion 131 and external thread portion 23 may also conform to the specifications of the metric standard thread, and the threaded fit between the first threaded section 231 and the internal thread portion 131 is an intermediate fit in the metric standard. The machining accuracy of 131 is 6H in the metric standard. When the outer diameter of the first threaded section 231 of the slider 20 is greater than 1.6 mm, the machining accuracy of the first threaded section 231 is 6g in the metric standard. When the outer diameter of a threaded section 231 is less than 1.4 mm, the machining accuracy grade of the first threaded section 231 is 6h of the metric standard, and the machining accuracy grade of the second threaded section 232 is higher than that of the first threaded section 231 The processing accuracy level of, is defined as 4h, and the thread gap T2 between the second threaded section 232 and the internal threaded portion 131 is smaller than the thread gap between the first threaded section 231 and the internal threaded portion 131, and can be further A positive clearance tolerance is added to the second thread section 232, and the clearance tolerance range can be defined as +0.1 mm to +0.06 mm to further reduce the gap between the second thread section 232 and the internal thread portion 131.

Preferably, the number of threaded teeth of the first threaded section 231 and the second threaded section 232 of the external threaded portion 23 and the internal threaded portion 131 is greater than or equal to the number of threaded teeth recommended by the standard specifications, so that the slider 20 and the arbor body 10 are more stable. For comparison with a slider with the same thread specification, the slider 20 of the present invention extends from an end of the flange 221 away from the head 21 to the slider 20 away from the The length of one end of the head 21 is longer than the length of the conventional slider from the end of the flange away from the head to the end of the conventional slider away from the head.

With the above technical features, the sealing member 25 can eliminate the gap between the slider 20 and the shank body 10, increase the stability of the combination, absorb vibration, and have a water-stop effect; and the external thread 23 of the slider 20 is two The segmental processing accuracy level allows the screwing process of the slider 10 and the tool bar body 20 to be tightened as the locking is performed, and the deflection error of the connection position during the locking process is reduced, and the tool bar is rotated at a high speed. Deflection and vibration improve the machining accuracy and service life of the tool holder.

10: Toolholder body 11: End face 13: Connection part 131: Internal thread part 132: Groove 133: Straight 20, 20A: slider 21: head 22: stop part 221: flange 222: Extension 223: Ring groove 23: External thread part 231: First thread section 232: second thread segment 233: separate slot 24: Through hole 25: Seal T1: Thread gap T2: Thread gap 80: Spindle 81: Clamping device 90: Toolholder 91: Toolholder body 911: Internal thread 92: Slider 921: Head 922: Flange 923: External thread

Figure 1 is a perspective exploded view of a preferred embodiment of the present invention. Figure 2 is a cross-sectional side view of a preferred embodiment of the present invention. Fig. 3 is a partial enlarged cross-sectional side view of the abutting portion of the preferred embodiment of the present invention. 4 is a partial enlarged cross-sectional side view of the external thread part of the preferred embodiment of the present invention. Figure 5 is a cross-sectional side view of another preferred embodiment of the present invention. Fig. 6 is a cross-sectional side view of a conventional cutter bar. Fig. 7 is a schematic diagram of the use of a conventional cutter bar.

10: Toolholder body

11: end face

13: Connection part

131: Internal thread

133: Straight

20: slider

21: head

22: Arrival Department

23: External thread

231: The first thread segment

232: second thread segment

233: partition slot

25: Seal

Claims (9)

A cutter bar with a firmly combined slider, which includes A shank body, which contains One end face; and A connecting part is formed in the main body of the shank in the axial direction, and an opening is formed on the end surface. The connecting part includes an internal threaded part and a straight part having the same axis. The internal threaded part is arranged on the side away from the end surface, And the processing accuracy specification of the internal thread part is in accordance with a standard thread specification, and the straight part is formed between the internal thread part and the end surface; and A slider is screw-connected to the main body of the arbor, and includes a head, a stop portion, and an external threaded portion. The head and the external threaded portion are respectively provided at opposite ends of the slider. The abutting part is formed between the head and the external thread part; wherein The stop includes A flange protruding radially from the slider, and one end of the flange away from the head abuts against the end surface of the shank body; An extension part inserted in the connecting part of the shank body and clearance fit with the straight part; A ring groove radially recessed in the extension part; and A sealing element arranged in the annular groove and closing the gap between the extension part of the slider and the straight part of the arbor body; and The external thread part is screwed and connected with the internal thread part of the shank body, which includes A first threaded section is located at an end far away from the head, the machining accuracy specification of the first threaded section is in accordance with the specification of the standard thread, and the threaded fit between the first threaded section and the internal threaded portion is the standard thread Intermediate coordination of the specifications; A second threaded section located at an end close to the head, the machining accuracy specification of the second threaded section is in accordance with the standard thread specification, and the machining accuracy grade is better than that of the first threaded section; and A spaced groove is radially recessed between the first threaded section and the second threaded section. According to claim 1, the shank with a firmly coupled slider, wherein the specification of the standard thread is the specification of the inch standard thread, and the machining accuracy grade of the internal thread part of the shank body is the 2B of the inch standard The processing accuracy level of the first thread section of the slider is 2A level of the British standard, and the processing accuracy level of the second thread section of the slider is 3A level of the British standard. According to claim 1, the shank with a firmly coupled slider, wherein the specification of the standard thread is that of a metric standard thread, and the processing accuracy of the internal thread part of the shank body is the metric standard 6H level When the outer diameter of the first threaded section of the slider is greater than or equal to 1.6 mm, the machining accuracy grade of the first threaded section is 6g of the metric standard, and when the outer diameter of the first threaded section is less than or equal to 1.4 mm, The processing accuracy grade of the first thread segment is 6h of the metric standard, and the processing accuracy of the second thread segment of the slider is 4h of the metric standard. According to claim 2 of the cutter bar with a firmly coupled slider, the processing tolerance of the second thread section of the slider is further added with a positive clearance tolerance. For the cutter bar with a firmly coupled slider as described in claim 4, the tolerance range of the compensation gap is +0.1 mm to +0.06 mm. According to claim 3, the cutter bar with a firmly coupled slider, wherein the machining tolerance of the second thread section of the slider is further added with a positive clearance tolerance. For the cutter bar with a firmly coupled slider as described in claim 6, the tolerance range of the compensation gap is +0.1 mm to +0.06 mm. According to claim 1, the shank with a firmly combined slider, wherein a groove recessed radially in the shank body is provided between the straight portion and the internal thread of the shank body. According to any one of claims 1 to 8, the shank with a firmly combined slider, wherein the slider further includes a through hole penetrating axially.

Images