Bidirectional high-precision output numerical control machine tool spindle unit

Abstract

A bidirectional high-precision output numerical control machine tool spindle unit comprises a spindle box, a spindle and a transmission box, the transmission box is fixed to the rear end of the spindle box, the spindle is installed in the spindle box, the rear end of the spindle extends into the transmission box and is provided with a first gear, and the front end of the spindle extends out of the spindle box and is provided with a chuck. Two transmission shafts are installed in the transmission box and distributed on the two sides of the main shaft, second gears are installed on the two transmission shafts respectively, the second gears are meshed with the first gears, and the transmission shafts are driven by gear motors installed at the rear end of the transmission box respectively. The utility model aims to overcome the defects in the prior art.

Description

Technical Field

[0001] The utility model belongs to the technical field of numerical control machine tools, and in particular relates to a bidirectional high-precision output numerical control machine tool spindle unit. Background Art

[0002] In the prior art, dual-motor driven spindles are mainly used to achieve high torque. For precision CNC machine tools, not only high torque but also bidirectional high-precision output is required. However, the transmission gears of the existing dual-drive spindle units are set in the spindle box, and the gear transmission point is far away from the spindle support part. The gear transmission impact affects the running accuracy of the workpiece at the front chuck of the spindle, and the gap between the transmission gears causes low bidirectional transmission accuracy. In addition, the transmission gears are set in the spindle box. Subsequent spindle transmission improvements and upgrades require the redesign of the spindle box and the replacement of the spindle box as a whole, which has high transformation costs. Utility Model Content

[0003] The utility model provides a bidirectional high-precision output CNC machine tool spindle unit to overcome the shortcomings of the prior art.

[0004] The technical solution adopted by the utility model is: a bidirectional high-precision output CNC machine tool spindle unit, including a spindle box, a spindle, and a transmission box, wherein the transmission box is fixed at the rear end of the spindle box, the spindle is installed in the spindle box, the rear end of the spindle extends into the transmission box and is installed with a first gear, the front end of the spindle extends out of the spindle box and is installed with a chuck, two transmission shafts are installed in the transmission box, and the two transmission shafts are distributed on both sides of the spindle, and second gears are respectively installed on the two transmission shafts; the second gear is meshed with the first gear, and the transmission shafts are respectively driven by reduction motors installed at the rear end of the transmission box.

[0005] The second gear and the first gear are both backlash-eliminating gears.

[0006] A circular grating is coaxially mounted on the main shaft, and the circular grating is located in the main shaft box.

[0007] A brake disc is also provided at the rear end of the main shaft. The brake disc is fixedly connected to the outer end of the first gear and is braked by a brake fixedly installed in the transmission box.

[0008] A bracket is fixed at the bottom of the transmission box, and the reduction motor is fixed on the bracket.

[0009] Compared with the prior art, the utility model has the following beneficial effects:

[0010] 1. The utility model arranges the transmission gear in the transmission box at the rear end of the spindle box, so that the gear transmission point is close to the rear end support part of the spindle, reducing the influence of the gear transmission impact on the running accuracy of the workpiece at the front end chuck of the spindle, and the transmission gear adopts the anti-backlash gear, which effectively reduces the reverse gap and improves the bidirectional transmission accuracy of the spindle.

[0011] 2. The utility model independently arranges the transmission gear in the transmission box at the rear end of the main spindle box. The subsequent improvement and upgrade of the main spindle transmission does not need to replace the main spindle box. It only needs to replace the gear with a suitable transmission ratio to achieve the conversion between high speed and small torque and low speed and large torque. The upgrade and transformation is simple and low cost.

[0012] 3. The utility model installs a circular grating on the spindle, so that the spindle transmission and the CNC machine tool form a full closed-loop control, effectively improving the processing accuracy of the CNC machine tool.

[0013] 4. The utility model sets a brake mechanism in the transmission box. When the brake disc is clamped by the brake mechanism at low pressure, the brake disc can still rotate at a certain speed driven by the main shaft. The brake disc adds a certain damping to the main shaft, eliminates the vibration of the main shaft, and further improves the processing accuracy of the CNC machine tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the structure of the utility model;

[0015] Figure 2 , 3 It is a schematic diagram of the cross-sectional structure of the utility model. DETAILED DESCRIPTION

[0016] The following is combined with Figure 1-3 The utility model is described in detail with specific implementation modes.

[0017] A bidirectional high-precision output CNC machine tool spindle unit, comprising a spindle box 1, a spindle 2, and a transmission box 3, wherein the transmission box 3 is fixed at the rear end of the spindle box 1, the spindle 2 is installed in the spindle box 1, the rear end of the spindle 2 extends into the transmission box 3 and is installed with a first gear 4, the front end of the spindle 2 extends out of the spindle box 1 and is installed with a chuck 5, two transmission shafts 6 are installed in the transmission box 3, and the two transmission shafts 6 are distributed on both sides of the spindle 2, second gears 8 are respectively installed on the two transmission shafts 6, the second gear 8 is meshed with the first gear 4, and the transmission shafts 6 are respectively driven by a reduction motor 7 installed at the rear end of the transmission box 3.

[0018] Furthermore, in order to reduce the reverse clearance, the second gear 8 and the first gear 4 are both backlash-eliminating gears.

[0019] In order to improve the positioning accuracy of the spindle operation, the spindle transmission and the CNC machine tool form a full closed-loop control, and effectively improve the processing accuracy of the CNC machine tool. A circular grating 9 is coaxially mounted on the spindle 2, and the circular grating 9 is located in the spindle box 1.

[0020] Furthermore, in order to make the main shaft completely stationary, a brake disc 10 is also provided at the rear end of the main shaft 2. The brake disc 10 is fixedly connected to the outer end of the first gear 4, and the brake disc 10 is braked by a brake 11 fixedly installed in the transmission box 3.

[0021] In the spindle feed mode: the brake 11 clamps the brake disc 10 at low pressure, adding a certain amount of damping to the spindle to eliminate spindle vibration, thereby achieving synchronous processing of the machine tool workpiece and the tool operation or synchronous processing of the workpiece operation and the tool stationary state.

[0022] In the spindle static mode: the brake 11 clamps the brake disc 10 with high pressure, so that the spindle is in a completely static state. It is mainly used to fix the workpiece and realize synchronous processing of the machine tool workpiece static state and the tool operation.

[0023] In one embodiment, the reduction motor 7 is connected to the transmission shaft 6 via a coupling, and the spindle box 1 is fixed on the base.

[0024] In one embodiment, in order to enhance the connection rigidity of the reduction motor 7 , a bracket 12 is fixed to the bottom of the transmission box 3 , and the reduction motor is fixed on the bracket 12 .

[0025] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the scope of implementation of the present invention. Therefore, all equivalent changes made to the contents described in the claims of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A bidirectional high-precision output CNC machine tool spindle unit, characterized in that: The invention comprises a spindle box (1), a spindle (2), and a transmission box (3), wherein the transmission box (3) is fixed at the rear end of the spindle box (1), the spindle (2) is installed in the spindle box (1), the rear end of the spindle (2) extends into the transmission box (3) and is installed with a first gear (4), the front end of the spindle (2) extends out of the spindle box (1) and is installed with a chuck (5), two transmission shafts (6) are installed in the transmission box (3), and the two transmission shafts (6) are distributed on both sides of the spindle (2), and second gears (8) are respectively installed on the two transmission shafts (6); the second gear (8) is meshed with the first gear (4), and the transmission shafts (6) are respectively driven by reduction motors (7) installed at the rear end of the transmission box (3).

2. The bidirectional high-precision output CNC machine tool spindle unit according to claim 1, characterized in that: The second gear (8) and the first gear (4) are both backlash-eliminating gears.

3. The bidirectional high-precision output CNC machine tool spindle unit according to claim 2, characterized in that: A circular grating (9) is coaxially mounted on the main shaft (2), and the circular grating (9) is located in the main shaft box (1).

4. The bidirectional high-precision output CNC machine tool spindle unit according to claim 1, 2 or 3, characterized in that: A brake disc (10) is also provided at the rear end of the main shaft (2). The brake disc (10) is fixedly connected to the outer end of the first gear (4), and the brake disc (10) is braked by a brake (11) fixedly installed in the transmission box (3).

5. The bidirectional high-precision output CNC machine tool spindle unit according to claim 4, characterized in that: A bracket (12) is fixed at the bottom of the transmission box (3), and the reduction motor (7) is fixed on the bracket (12).

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