Large boring and milling machine ram gravity center fine adjustment device

Abstract

The invention discloses a large boring and milling machine ram gravity center fine adjustment device which comprises a first fine adjustment mechanism, a second fine adjustment mechanism and a monitoring system which are arranged on a supporting plate of a boring and milling machine, the first fine adjustment mechanism is provided with a first motor and a first cam, and the first cam is located in a first sliding way of a ram; the second fine adjustment mechanism is provided with a second motor and a second cam, the second cam is located in a second sliding way of the ram, and the adjustment amount of the first cam and the second cam is smaller than 2 mm. The monitoring system comprises a first microsensor for monitoring horizontal offset and a second microsensor for monitoring vertical offset. The first micro-sensor and the second micro-sensor are used for monitoring the horizontal offset and the vertical offset of the ram respectively, each motor is provided with an eccentric cam, the motors and the cams are used for compensating sagging or rising of the ram caused by center-of-gravity offset, and horizontal offset caused by recutting can be compensated, so that the precision of the ram is improved, and the precision of the ram is improved. And the service life of the large boring and milling machine is prolonged.

Description

Technical Field

[0001] The invention relates to the field of center of gravity adjustment of large boring and milling machines, in particular to a ram center of gravity fine-tuning device for large boring and milling machines. Background Art

[0002] Boring and milling machines are a common type of machine tool in the machining field. They integrate the functions of boring and milling machines, making the machining more efficient and accurate, greatly improving product quality and labor efficiency. Large boring and milling machines mainly include CNC axes such as X / Y / Z / W. The Z axis is installed on the large column of the boring and milling machine. The Z axis is equipped with a milling cutter through a milling head, so the Z axis is the most frequently moving axis. The Z axis of the boring and milling machine generally uses a ram, and the high-precision operation of the Z axis is ensured by a servo motor, a lead screw and a linear guide (or a sliding guide).

[0003] In actual processing, large CNC boring and milling machines generally process large workpieces, with long rectangular slides and heavy milling heads. During processing, boring and milling machines, as heavy-cutting equipment, have a large cutting volume, which can cause the rectangular slide to deflect downward or the slide to come up when cutting large amounts, which can affect processing accuracy. In addition, the Z-axis movement of large boring and milling machines is usually more than one meter, and the slight deformation of the guide rails will be magnified according to the force length, further causing the slide and boring spindle to sag, and further causing the slide center of gravity to shift.

[0004] At present, there are two main ways to adjust the center of gravity offset of the ram of large boring and milling machines. The first is to calculate the offset position to pre-set the offset value, and then take linear compensation; the second is to rely on the electronic balance ruler to give the control system an offset. The control system controls the solenoid valve according to the offset, thereby controlling the hydraulic flow. The hydraulic cylinder pulls the wire rope connecting the ram and the hydraulic cylinder with the size of the hydraulic flow to adjust and compensate. Although both methods can play a role in compensation, the compensation offset has disadvantages such as inaccuracy and slow response time. In addition, large CNC boring and milling machine tools are all heavy-cutting machine tools with large feed rates. The ram will change in the direction of the center of gravity offset under heavy-load processing. In the past, the compensation for the center of gravity offset of the ram was in the vertical direction, and there was no compensation in the horizontal direction under heavy cutting conditions, resulting in insufficient processing accuracy of large CNC boring and milling machine tools. Therefore, it is very important to quickly determine the ram offset error of large boring and milling machines and quickly compensate in the vertical and horizontal directions. Summary of the invention

[0005] In view of this, the present invention proposes a large-scale boring and milling machine slide center of gravity offset fine-tuning device, which uses an eccentric cam to achieve center of gravity adjustment, can quickly and in real time feedback and calibrate the slide, and thus improve the processing accuracy of the workpiece.

[0006] To achieve the above object, the present invention adopts the following technical solutions: The device for fine-tuning the center-of-gravity offset of the ram of a large boring and milling machine of the present invention comprises a first fine-tuning mechanism, a second fine-tuning mechanism and a monitoring system arranged on a support plate of the boring and milling machine, wherein the support plate is an L-shaped structure, and the ram of the boring and milling machine is located inside the support plate; the support plate has a first mounting portion and a second mounting portion perpendicular to each other, the first fine-tuning mechanism drives the ram to move horizontally, and has a first motor fixed to the first mounting portion and a first cam driven by the first motor, the first cam is arranged horizontally and is located in the first slideway of the ram; the second fine-tuning mechanism drives the ram to move up and down, and has a second motor fixed to the second mounting portion and a second cam driven by the second motor, the second cam is located in the second slideway of the ram, and the adjustment amount of the first cam and the second cam is less than 2 mm; The monitoring system includes a PLC for controlling the first motor and the second motor, a first trace sensor for monitoring the horizontal offset of the slide, a second trace sensor and a receiver for monitoring the vertical offset of the slide, the first trace sensor and the second trace sensor are connected to the receiver signal, the receiver is connected to the control system of the boring and milling machine, the control system is connected to the PLC, and the control input ends of the first motor and the second motor are connected to the control output ends of the PLC.

[0007] The beneficial effects are as follows: the present invention utilizes a first trace sensor to monitor the horizontal offset of the slide, utilizes a second trace sensor to monitor the vertical offset of the slide, controls the forward and reverse rotation of the first motor and the second motor through a control system and a PLC, and each motor has an eccentrically designed cam. The eccentrically designed second cam can be used to achieve vertical fine-tuning, thereby adjusting the droop or rise of the slide caused by the center of gravity offset; the first cam is used to achieve horizontal fine-tuning, thereby adjusting the horizontal offset caused by heavy cutting, thereby overcoming the error caused by the uncertainty of the center of gravity of the slide of a large boring and milling machine, improving the machining accuracy of the workpiece, and extending the life of the large boring and milling machine.

[0008] Preferably, a first bearing group that cooperates with the side wall of the first slideway is symmetrically arranged in the first slideway, and a second bearing group that cooperates with the side wall of the second slideway is arranged in the second slideway. The beneficial effect is that the bearings of the slideway and the bearing group are slidably matched to ensure that the slide ram can be relatively displaced under force.

[0009] Preferably, the first bearing group and the second bearing group have the same structure, both including a bearing seat and a plurality of roller bearings arranged in the bearing seat, each roller bearing portion is located outside the bearing seat, and a bearing gland is fixedly connected to the upper surface of the bearing seat by screws; wherein, the plurality of roller bearings of the first bearing group are in rolling cooperation with the first slideway, and the plurality of roller bearings of the second bearing group are in rolling cooperation with the second slideway. The beneficial effect is that the present invention sets a bearing group in cooperation with each slideway, and the bearing group can withstand a large radial force, avoids the blocking of the ram during the fine-tuning process, and ensures the slight movement of the ram.

[0010] Preferably, the first motor and the second motor are both servo motors. The first motor and the second motor both have a driver, the control input end of the driver is connected to the control output end of the driver, and the start and stop of each motor, as well as the forward and reverse rotation of the motor are controlled by PLC, thereby adjusting the center of gravity of the ram.

[0011] Preferably, the first trace sensor and the second trace sensor are both trace distance measuring sensors, thereby monitoring the vertical displacement and horizontal displacement of the ram in real time.

[0012] The present invention utilizes a first trace sensor to monitor the horizontal offset of the slide, utilizes a second trace sensor to monitor the vertical offset of the slide, controls the forward and reverse rotation of the first motor and the second motor through a control system and a PLC, and each motor is provided with an eccentrically designed cam. The eccentrically designed second cam can be used to achieve vertical fine-tuning, thereby adjusting the droop or rise of the slide caused by the center of gravity offset; the first cam is used to achieve horizontal fine-tuning, thereby adjusting the horizontal offset caused by heavy cutting, thereby overcoming the error caused by the uncertainty of the center of gravity of the slide of a large boring and milling machine, improving the processing accuracy of the workpiece, and extending the life of the large boring and milling machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the installation of the present invention on a boring and milling machine.

[0014] Figure 2 It is a schematic cross-sectional view of the ram of the present invention.

[0015] Figure 3 Schematic diagram of the support plate of the present invention. Figure 3 In the figure, a is a side view of the pallet, and b is a front view of the pallet (i.e., the right view of a).

[0016] Figure 4 It is a side view of the present invention.

[0017] Figure 5 yes Figure 4 An enlarged schematic diagram of the second fine-tuning mechanism.

[0018] Figure 6 yes Figure 4 Right side view of the middle ram (with the second bearing set and the second cam in the second slideway).

[0019] Figure 7 yes Figure 4 Top view of the middle ram (with the first bearing set and the first cam in the first slideway).

[0020] Figure 8 Schematic diagram of the bearing seat of the present invention.

[0021] Fig. 9 It is a schematic diagram of the installation of the roller bearing of the present invention in the bearing seat.

[0022] Fig.10 Schematic diagram of the first bearing group of the present invention.

[0023] Fig.11 Schematic diagram of the first cam of the present invention.

[0024] Fig.12 yes Fig.11 BB direction schematic diagram.

[0025] Fig.13 It is a circuit principle block diagram of the present invention. DETAILED DESCRIPTION

[0026] The following is a detailed description of an embodiment of the present invention in conjunction with the accompanying drawings. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiment.

[0027] It should be noted that, in the description of the present invention, relational terms such as “first” and “second” are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations.

[0028] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected" and "connection" that may appear should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] like Figure 1-13As shown, the center-of-gravity fine-tuning mechanism of the ram of the large boring and milling machine of the present invention comprises a first fine-tuning mechanism, a second fine-tuning mechanism and a monitoring system arranged on a support plate 2 of the boring and milling machine (installed on a large column 1 of the boring and milling machine); the first fine-tuning mechanism and the second fine-tuning mechanism have the same structure. To meet the installation requirements of the first fine-tuning mechanism and the second fine-tuning mechanism, the support plate 2 is an L-shaped structure, comprising a first mounting portion 2.1 and a second mounting portion 2.2 perpendicular to each other, and the ram 3 is located on the inner side of the support plate 2 and can move relative to the support plate 2; the first fine-tuning mechanism is used for horizontal fine-tuning of the ram 3, and has a first fine-tuning mechanism fixedly connected to the left end of the first mounting portion 2.1. The first motor 4.1 of the first cam 4.2 and the first cam 4.2 driven by the first motor 4.1, the first cam 4.2 is located in the first slideway 3.1 at the top of the ram 3, the first cam 4.2 is key-connected with the motor shaft (vertically arranged) of the first motor 4.1 and has interference fit, the highest point F1 of the first cam 4.2 passes through the center line of its keyway 4.2a, the center line L of the keyway 4.2a is parallel to the first slideway 3.1, the first cam 4.2 and the motor shaft of the first motor 4.1 are eccentrically designed, and when the protruding part of the first cam 4.2 rotates to contact the first slideway 3.1, it drives the ram 3 to make a horizontal fine adjustment, and the adjustment amount is within 1mm; The second fine-tuning mechanism is used for vertical fine-tuning of the ram 3, and comprises a second motor 5.1 fixed to the left end of the second mounting portion 2.2 (the second motor 5.1 and the first motor 4.1 are both mounted on the left end of the support plate) and a second cam 5.2 driven by the second motor 5.1. The second cam 5.2 and the motor shaft of the second motor 5.1 are eccentrically designed. The second cam 5.2 is located in the second slideway 3.2 of the ram 3. The second slideway 3.2 is provided in the middle of one side of the ram 3. The second cam 5.2 is key-connected with the motor shaft (horizontally arranged) of the second motor 5.1 and has an interference fit. The highest point F2 of the second cam 5.2 passes through the center line of its keyway, and the center line of the keyway is parallel to the second slideway 3.2. When the protruding portion of the second cam 5.2 rotates to contact the second slideway 3.2, it drives the ram 3 to be vertically fine-tuned, and the adjustment amount is within 1 mm. The monitoring system includes a PLC for controlling a first motor 4.1 and a second motor 5.1, a first trace sensor 5.1 for monitoring the horizontal offset of the ram 3, a second trace sensor 5.2 for monitoring the vertical offset of the ram 3, and a receiver. The first trace sensor 5.1 and the second trace sensor 5.2 are connected to the receiver for transmission. The first trace sensor 5.1 and the second trace sensor 5.2 transmit the monitored signal to the receiver. The receiver is connected to the control system of the boring and milling machine for transmission. The control system processes the signal to determine the horizontal offset and vertical offset of the center of gravity of the ram 3; the control system is connected to the PLC for transmission, and then the offset is transmitted to the PLC; the control input ends of the first motor 4.1 and the second motor 5.1 are connected to the control output ends of the PLC, and the PLC is used to control the forward and reverse rotation and on and off conditions of the first motor 4.1 and the second motor 5.1.

[0030] The present invention utilizes a first trace sensor 5.1 to monitor the vertical displacement of the slide 3, utilizes a second trace sensor 5.2 to monitor the horizontal displacement of the slide 3, controls the forward and reverse rotation of the first motor 4.1 and the second motor 5.1 through a control system and a PLC, and each motor is provided with an eccentrically designed cam. The eccentrically designed second cam 5.2 can be used to achieve vertical fine-tuning to adjust the droop or rise of the slide 3 caused by the center of gravity offset; the first cam 4.2 is used to achieve horizontal fine-tuning to adjust the horizontal displacement caused by heavy cutting, thereby overcoming the error caused by the uncertainty of the center of gravity of the slide 3 of the large boring and milling machine, improving the processing accuracy of the workpiece, and extending the life of the large boring and milling machine.

[0031] Combination Figure 4-10 It can be seen that the first slide 3.1 is symmetrically provided with a first bearing group 4.3 that cooperates with the first cam 4.2, and the first cam 4.2 is located between the two groups of first bearings; similarly, the second slide 3.2 is symmetrically provided with two groups of second bearing groups 5.3 that cooperate with the second cam 5.2, and the second cam 5.2 is located between the two groups of second bearing groups 5.3; the first bearing group 4.3 and the second bearing group 5.3 have the same structure, both including a bearing seat C2 with three bearing holes C1, three roller bearings C3 are installed side by side in the bearing seat C2, and the upper surface of the bearing seat C2 is fixed with a bearing cover C5 by screws; wherein each bearing hole C1 has an opening C4, so that a part of each roller bearing C3 is located outside the bearing seat C2. During actual installation, the roller bearings C3 of each group of first bearing groups 4.3 are rollingly matched with the side wall of the first slide (see for details). Figure 4 and Figure 7 ), the roller bearings of each second bearing group 5.3 roll with the side wall of the second slideway. During operation, the side-by-side roller bearings C3 can not only withstand a large radial force, but also ensure that the ram 3 is slightly offset relative to the cam during the rotation of the cam to avoid blocking of the ram 3.

[0032] During actual installation, both the first motor 4.1 and the second motor 5.1 are servo motors. The motor shaft of the first motor 4.1 passes through the first mounting portion 2.1 downward, and is then connected to the first cam 4.2; the motor shaft of the second motor 5.1 passes through the second mounting portion 2.2 horizontally, and is then connected to the second cam 5.2. Both the first motor 4.1 and the second motor 5.1 have a driver, and the PLC is connected to the driver. The PLC controls the driver to realize the on-off and forward and reverse rotation of the motor, so as to realize the horizontal fine-tuning and vertical fine-tuning requirements of the slide 3, and further realize the fine-tuning of the center of gravity of the slide 3. A measuring rod is installed on the first mounting portion 2.1 of the support plate 2, and the first micro sensor 5.1 and the second micro sensor 5.2 are fixed on the measuring rod. The first micro sensor 5.1 and the second micro sensor 5.2 are both micro distance sensors, so as to realize real-time monitoring of the vertical offset and horizontal offset of the slide 3.

[0033] The working principle and working process of the present invention are as follows: during the operation of the boring and milling machine, the first micro sensor 5.1 monitors the horizontal offset of the ram 3 in real time, and the second micro sensor 5.2 monitors the vertical offset of the ram 3 in real time; when the horizontal offset exceeds the set value, the control system transmits the adjustment signal to the PLC, and the PLC sends a fine-tuning instruction to the driver of the first motor 4.1, the first motor 4.1 works and drives the first cam 4.2 to rotate, and the protrusion of the first cam 4.2 contacts the first bearing group 4.3 in the first slideway 3.1 and transmits force to the first bearing group 4.3, The first bearing group 4.3 is subjected to force to cause the slide 3 to move horizontally until the horizontal position of the slide 3 is within the set range; when the vertical offset exceeds the set value, the control system transmits an adjustment signal to the PLC, and the PLC sends a fine-tuning command to the driver of the second motor 5.1, the second motor 5.1 works and drives the second cam 5.2 to rotate, the protrusion of the second cam 5.2 contacts the second bearing group 5.3 in the second slideway 3.2, and the force is transmitted to the second bearing group 5.3, and the second bearing group 5.3 is subjected to force to cause the slide 3 to move vertically slightly until the vertical position of the slide 3 is within the set range.

[0034] The present invention utilizes a servo motor + cam combination to achieve the center of gravity compensation of the slide 3 in the vertical and horizontal directions, thereby improving the manufacturing accuracy of the workpiece and solving the error caused by the uncertainty of the center of gravity of the slide 3 of the large boring and milling machine. Its practical application will definitely bring about an improvement in the processing accuracy of large parts.

[0035] Finally, it should be emphasized that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions recorded in the aforementioned embodiments without creative work, or replace some of the technical features therein with equivalents. Therefore, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A device for fine-tuning the center of gravity offset of a ram of a large boring and milling machine, characterized in that: It comprises a first fine-tuning mechanism, a second fine-tuning mechanism and a monitoring system arranged on a support plate of a boring and milling machine, wherein the support plate is an L-shaped structure, and a ram of the boring and milling machine is located inside the support plate; The support plate has a first mounting portion and a second mounting portion which are perpendicular to each other. The first fine-adjusting mechanism drives the ram to move horizontally, and has a first motor fixed to the first mounting portion and a first cam driven by the first motor. The first cam is horizontally arranged and located in the first slideway of the ram. The second fine-adjusting mechanism drives the ram to move up and down, and has a second motor fixed to the second mounting portion and a second cam driven by the second motor. The second cam is located in the second slideway of the ram. The adjustment amount of the first cam and the second cam is less than 2 mm. The monitoring system includes a PLC for controlling the first motor and the second motor, a first trace sensor for monitoring the horizontal offset of the slide, a second trace sensor and a receiver for monitoring the vertical offset of the slide, the first trace sensor and the second trace sensor are connected to the receiver signal, the receiver is connected to the control system of the boring and milling machine, the control system is connected to the PLC, and the control input ends of the first motor and the second motor are connected to the control output ends of the PLC.

2. The device for fine-tuning the center of gravity offset of the ram of a large boring and milling machine according to claim 1 is characterized in that: A first bearing group matched with the side wall of the first slideway is symmetrically arranged in the first slideway, and a second bearing group matched with the side wall of the second slideway is arranged in the second slideway.

3. The device for fine-tuning the center of gravity offset of the ram of a large boring and milling machine according to claim 2 is characterized in that: The first bearing group and the second bearing group have the same structure, both including a bearing seat and a plurality of roller bearings arranged in the bearing seat, each roller bearing is partially located outside the bearing seat, and a bearing cover is fixed to the upper surface of the bearing seat by screws; wherein, the plurality of roller bearings of the first bearing group are in rolling cooperation with the first slideway, and the plurality of roller bearings of the second bearing group are in rolling cooperation with the second slideway.

4. The device for fine-tuning the center of gravity offset of the ram of a large boring and milling machine according to claim 1, characterized in that: The first motor and the second motor are both servo motors.

5. The device for fine-tuning the center of gravity offset of the ram of a large boring and milling machine according to claim 1 is characterized in that: The first micro-amount sensor and the second micro-amount sensor are both micro-amount distance measuring sensors.

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