Electric turret clamping device

Abstract

An electric turret clamping device according to the present invention relates to an electric turret clamping device of a machine tool, which rotates a turret disc through an electrical driving and enables a disc to be locked through a main shaft clamping, and comprises a self-locking structure via a worm shaft provided as a pair with a worm wheel, and a clamping portion clamping the main shaft with a pressure amplified by an air booster portion, thereby strongly locking the disc without using a high-pressure hydraulic device.

Description

Electric turret clamping device

[0001] The present invention relates to an electric turret clamping device, and more particularly, to an electric turret clamping device for a machine tool that rotates a turret disk through electric drive and is capable of locking the disk through main shaft clamping.

[0002] Currently, the need for electrification is growing in the machine tool industry due to the global shift to smart factories, global environmental regulations, and trends toward safety and energy efficiency.

[0003] Machine tools are machines that process mechanical parts used in core industries such as automobiles, shipbuilding, semiconductors, displays, IT, and aerospace. Among these, lathes are comprised of a chuck for holding the workpiece, a spindle for rotating it, a tailstock to support the center of the workpiece, and a turret tool holder equipped with cutting tools. However, conventional lathes primarily rely on hydraulics as their driving force, necessitating the development of motorized modules to meet the global demand for electrification.

[0004] Meanwhile, conventional turret tool holders have used a hydraulically operated clamping / unclamping method in which a piston within the body, operated by hydraulic pressure, moves axially forward to lock the turret, thereby advancing the lifting axis of the main spindle, thereby switching the clamped positioning part to an unclamped state.

[0005] However, this conventional clamping method has caused problems such as noise and oil leakage due to high-pressure hydraulic devices, so there is a need to develop technology to overcome these problems.

[0006] The present invention is intended to solve the above-mentioned problems, and its purpose is to provide an electric turret clamping device capable of locking a turret disk by replacing a conventional high-pressure hydraulic device.

[0007] Another object of the present invention is to provide an electric turret clamping device capable of rotating a disk electrically.

[0008] The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems to be solved by the present invention that are not mentioned herein will be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0009] In order to solve the above-described problem, the electric turret clamping device according to the present invention comprises: a tool post body; a main shaft extending forward and backward from the tool post body and rotatably installed with respect to the tool post body; a disk installed at the front end of the main shaft and rotating integrally with the main shaft; a worm wheel fixedly installed on the outer surface of the main shaft at the rear of the disk, having a worm gear thread formed on the outer surface and rotating integrally with the main shaft; a worm shaft installed inside the tool post body to mesh with the worm gear thread and receiving power from a driving unit to rotate the worm wheel; a housing fixedly installed in a tubular shape inside the tool post body having an inner diameter larger than the outer diameter of the main shaft; an oil inlet space formed on the outer surface of the housing; and a clamping pad formed on the inner surface of the housing and contacting the main shaft; and a clamping unit installed in communication with the oil inlet space at one side of the tool post body and amplifying the pressure of applied air. It is composed of an air booster section equipped with a shared pressure booster that supplies oil to an oil inlet space.

[0010] Preferably, the main shaft may be characterized in that a cylindrical module is installed with which the clamping pad of the clamping portion comes into contact.

[0011] Preferably, the clamping pad may be characterized in that protrusions are formed at regular intervals on the inner surface that comes into contact with the cylindrical module.

[0012] Preferably, the cylindrical module may further include a plurality of catches formed as protrusions arranged at regular intervals on the outer surface that comes into contact with the clamping pad.

[0013] Preferably, the air booster unit may include an air cylinder installed on one side of the inside of the tool body and having a piston that advances when air pressure is applied to the inside, and an operating oil pipe filled with operating oil, one end of which is connected to the air cylinder and the other end of which is connected to the oil inlet space.

[0014] Preferably, the rotating part may be characterized in that the worm shafts are provided in pairs and installed facing each other vertically with respect to the worm wheel.

[0015] The electric turret clamping device according to the present invention includes a self-locking configuration by a worm shaft provided as a pair with a worm wheel, and a clamping unit that clamps a main shaft with pressure amplified by an air booster unit, thereby having the effect of strongly locking a disk even without a high-pressure hydraulic device.

[0016] The electric turret clamping device according to the present invention has the effect of being able to rotate the disk electrically, since the worm shaft rotates with the power generated by the electric motor, and the rotational power is transmitted to the disk.

[0017] FIG. 1 is a side cross-sectional view showing one embodiment of an electric turret clamping device according to the present invention.

[0018] FIG. 2 is a plan view showing one embodiment of an electric turret clamping device according to the present invention.

[0019] Figure 3 is an enlarged partial view of part A of Figure 2.

[0020] Figure 4 is an enlarged partial view of part B of Figure 2.

[0021] Figure 5 is a conceptual diagram showing the form in which a worm shaft meshes with the worm gear screw thread of a worm wheel.

[0022] Figure 6 is a conceptual diagram showing that the heights of the protrusions formed at the center and front and rear of the clamping pad are formed differently.

[0023] <Explanation of symbols>

[0024] 110: Tool body

[0025] 120: Disk

[0026] 130: Main shaft

[0027] 131: Cylindrical module

[0028] 140: Rotating part

[0029] 141: Worm wheel

[0030] 1411: Worm gear thread

[0031] 142: Worm shaft

[0032] 150: Clamping section

[0033] 151: Housing

[0034] 152: Oil inlet space

[0035] 153: Clamping pad

[0036] 153a: Central protrusion

[0037] 153b: Outer protrusion

[0038] 154: Sealing member

[0039] 160: Air booster section

[0040] 161: Air cylinder

[0041] 162: Piston

[0042] 163: Operating oil pipe

[0043] 164: Pressure control module

[0044] 170: Encoder section

[0045] The advantages and features of the present invention, and the methods for achieving them, will become clearer with reference to the embodiments described in detail below together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various different forms. These embodiments are provided only to ensure that the disclosure of the present invention is complete and to fully inform those skilled in the art of the scope of the invention. In addition, the terminology used herein is for the purpose of describing the embodiments and is not intended to limit the present invention. In this specification, the singular form also includes the plural form unless specifically stated otherwise.

[0046] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings. Meanwhile, schematic and detailed descriptions of the configurations, operations, and effects readily apparent to those skilled in the art will be briefly or omitted, focusing on the details relevant to the present invention.

[0047] First, referring to FIGS. 1 and 2, the electric turret clamping device according to the present invention is configured to include a tool body (110), a disk (120), a main shaft (130), a rotating part (140), a clamping part (150), and an air booster part (160).

[0048] In the present invention, the direction in which the disk (120) is installed on the tool body (110) is set as the front side and the other side as the rear side.

[0049] The above tool post body (110) corresponds to the main body of the tool post and can be installed in a machine tool including an electric lathe. In addition, a main shaft (130) and a rotating part (140) that rotates the main shaft (130) are installed on the inside, and a disk (120) is installed on the front so as to be rotatable.

[0050] Next, the above disk (120) is installed at the front end of the main shaft (130) and rotates integrally with the main shaft (130).

[0051] Specifically, the front part of the disk (120) can have multiple tools installed and can be indexed to rotate as needed so that a tool suitable for machining the workpiece is positioned at the workpiece position.

[0052] Next, the main shaft (130) extends forward and backward to the tool body (110) and is installed rotatably with respect to the tool body (110).

[0053] Specifically, the main shaft (130) may be formed in a cylindrical shape and installed in a form in which the rear side is inserted into the tool body (110).

[0054] Next, as shown in Fig. 1, the rotating part (140) is fixedly installed on one side of the outer surface of the main shaft (130) and can rotate by receiving power from a driving part (not shown).

[0055] Specifically, the above-mentioned rotating part (140) is configured to include a worm wheel (141) and a worm shaft (142).

[0056] The above worm wheel (141) is fixedly installed on the outer surface of the main shaft (130) at the rear of the disk (120), has a worm gear screw thread (1411) formed on the outer surface, and is configured to rotate integrally with the main shaft (130).

[0057] In addition, the worm shaft (142) is installed so as to mesh with the worm gear screw thread (1411) of the worm wheel (141) inside the tool body (110). And, it receives power from the driving unit by the electric motor and serves to rotate the worm wheel (141).

[0058] In addition, the worm wheel (141) and the worm shaft (142) are formed in a long worm gear structure and can be formed in a convex tooth shape and a concave tooth shape.

[0059] Compared to a general worm gear, the long-wheel worm gear has 2 to 4 times more contact between the teeth of the cross-axis gears where the worm and wheel surround each other, and has a tooth contact shape that is advantageous for lubrication.

[0060] Additionally, it is more than three times more resistant to external impact, resulting in superior efficiency, high reduction ratios, and miniaturization. Furthermore, it offers the advantages of low noise, vibration, and roughness, low frictional heat generation, and a long service life.

[0061] In addition, an important feature of the long worm gear is self-locking. That is, it has a feature that prevents reverse driving, which prevents the worm wheel (141) from rotating in reverse, thereby enabling locking of the disk (120).

[0062] Basically, the worm gear drive method has less backlash than the general gear method, but the worm shaft (142) according to the present invention is designed to have no backlash effect and high power transmission power due to the shape in which the teeth of the long worm mesh with the worm gear screw thread (1411).

[0063] In addition, the worm shaft (142) is provided as a pair and can be installed so as to mesh with the worm gear screw thread (1411) of the worm wheel (141) at the upper and lower ends inside the tool body (110).

[0064] Specifically, since the present invention is provided with a pair of worm shafts (142), power loss is lower than that of a single worm shaft structure, and a high fixing effect of the worm wheel (141) when stopped can be expected.

[0065] More specifically, a pair of worm shafts (142) are installed facing each other vertically with respect to the worm wheel (141), and rotate in opposite directions to rotate the worm wheel (141).

[0066] At this time, a mating surface that compensates for the backlash that may be formed minutely at one end is formed at the other end, thereby minimizing the shock and noise caused by the backlash that may occur when the worm wheel (141) rotates from one direction to the opposite direction.

[0067] And since the worm shaft (142) is installed as a pair, when the worm shaft (142) is fixed, the worm wheel (141) is firmly fixed and does not rotate, and the loss of power transmitted to the worm wheel (141) when the worm shaft (142) rotates is reduced.

[0068] FIG. 5 is a conceptual diagram showing a form in which a worm shaft (142) is engaged with a worm gear screw thread (1411) of a worm wheel (141), and with reference to FIG. 5, backlash A between the upper worm shaft and the upper worm gear screw thread (1411) is compensated for by the meshing surface C of the lower worm shaft and the lower worm gear screw thread (1411), and backlash D between the lower worm shaft and the lower worm gear screw thread (1411) is compensated for by the meshing surface B of the upper worm shaft and the upper worm gear screw thread (1411), so that the movement of the worm wheel (141) due to backlash can be minimized.

[0069] Next, as illustrated in Fig. 1, the clamping portion (150) is installed on one side of the inside of the tool body (110) and is configured to restrict rotation by gripping the outer surface of the main shaft (130).

[0070] Specifically, as illustrated in FIG. 3, the clamping portion (150) is configured to include a housing (151), an oil inlet space (152), and a clamping pad (153).

[0071] The above housing (151) is fixedly installed in a tubular shape with an inner diameter larger than the outer diameter of the main shaft (130) on the inside of the tool post body (110). Specifically, it is formed as a tube that surrounds the outer surface of the main shaft (130) located at the rear of the disk (120) and the front of the rotating part (140), and the front end of the housing (151) is fixedly installed on the front end of the tool post body (110). In addition, a bearing may be provided on the inside of the housing (151) to ensure smooth rotation of the main shaft (130).

[0072] In addition, the oil inflow space (152) is formed in the space between the outer surface of the housing (151) and the tool body (110), and when oil flows into the oil inflow space (152), the housing (151) is deformed in the direction of the main shaft (130).

[0073] That is, when oil flows into the oil inflow space (152) and the internal pressure increases, the housing (151) forming the inner surface is deformed, and the space inside the oil inflow space (152) expands.

[0074] In addition, the clamping pad (153) is formed on the inner surface of the housing (151) and is provided as a pad that comes into contact with the main shaft (130).

[0075] Specifically, the clamping pad (153) forms the inner surface of the oil inlet space (152), and when the oil inlet space (153) expands, it directly contacts the outer surface of the main shaft (130) to form friction and a catch, thereby restricting the rotation of the main shaft (130).

[0076] Additionally, as illustrated in FIG. 1, the main shaft (130) may further include a cylindrical module (131) with which the clamping pad (153) comes into contact.

[0077] The above cylindrical module (131) is a cylinder fixedly installed on the outer surface of the main shaft (130) and has an outer diameter larger than the outer diameter of the main shaft (130). At this time, the housing (151) is installed in a form that surrounds the cylindrical module (131). Therefore, the contact area of ​​the clamping pad (153) increases, so that a stronger frictional force can be formed.

[0078] Meanwhile, the inner surface of the clamping pad (153) that comes into contact with the outer surface of the main shaft (130) or cylindrical module (131) may have a preset pattern formed to increase friction.

[0079] Specifically, protrusions may be formed at regular intervals on the inner surface of the clamping pad (153).

[0080] More specifically, the protrusion formed on the clamping pad (153) can be formed at different heights depending on the position where it comes into contact with the cylindrical module (131).

[0081] Preferably, as shown in Fig. 6, the height h2 of the outer protrusions (153b) formed at the front and rear may be formed higher than the height h1 of the central protrusion (153a) formed at the center of the clamping pad (153) so that the clamping pad (153) can evenly apply braking force to the outer surface of the cylindrical module (131).

[0082] In addition, a plurality of catches may be formed on the outer surface of the cylindrical module (131) by protrusions arranged at regular intervals on the outer surface that comes into contact with the clamping pad (153).

[0083] Additionally, there may be an embodiment in which the catch formed on the front and rear portions of the outer surface of the cylindrical module (131) has a higher height than the catch formed on the center portion.

[0084] In addition, a pattern may be formed in a ring shape, a straight line shape, a spiral shape, a diagonal shape, etc. on the outer surface of the cylindrical module (131) that comes into contact with the clamping pad (153), and any shape may be formed as long as the pattern can form a braking force by coming into contact with the clamping pad (153).

[0085] In addition, a pattern may be formed in a ring shape, a straight line shape, a spiral shape, a diagonal shape, etc. on the inner surface of the clamping pad (153) that comes into contact with the cylindrical module (131), and any shape may be formed as long as the pattern can form a braking force by coming into contact with the cylindrical module (131).

[0086] Meanwhile, as shown in Fig. 3, a sealing member (154) is formed in front and behind the oil inlet space (152), and serves to prevent leakage of oil flowing into the oil inlet space (152).

[0087] Next, as shown in Fig. 2, the air booster unit (160) is installed so as to be in communication with the oil inlet space (152) on one side of the tool body (110), and is equipped with a shared pressure booster that amplifies the pressure of the applied air and supplies oil to the oil inlet space (152).

[0088] Here, oil is introduced into the oil inlet space (152) and acts as operating oil to increase the internal pressure of the oil inlet space (152) and cause expansion.

[0089] And, as shown in Fig. 2, it is preferable that the air booster unit (160) be installed attached to the inner wall of the tool body (110) at a location that does not interfere with the driving of the worm shaft (142).

[0090] Specifically, as illustrated in FIG. 4, the air booster unit (160) is configured to include an air cylinder (161), a piston (162), and an operating oil pipe (163).

[0091] The above air cylinder (161) is configured as a cylinder to which air pressure can be applied inside, and includes a piston (162) that moves forward by air pressure inside.

[0092] The above-mentioned operating oil pipe (163) is filled with operating oil inside, one end is connected to the air cylinder (161), and the other end is connected to the oil inlet space (152).

[0093] That is, the pressure applied by the piston (162) in the air cylinder (161) is transmitted to the operating oil of the operating oil pipe (163), and the operating oil fills the inside of the oil tube (152) with strong pressure.

[0094] The head of the piston (162) is formed with a diameter corresponding to the inner circumference of the air cylinder (161), and the rod of the piston (162) that pressurizes the operating oil has a diameter corresponding to the operating oil pipe (163).

[0095] At this time, the operating oil pipe (163) has a smaller cross-sectional area than the piston head, which causes pressure amplification through area reduction. That is, the operating oil is discharged into the oil inlet space (152) at a pressure stronger than the air pressure applied to the piston (162).

[0096] The pressure of the operating oil discharged from the above operating oil pipe (163) can be obtained by the following [Calculation Formula 1].

[0097] [Calculation Formula 1]

[0098]

[0099] (Here, P is the operating oil pipe discharge pressure, P1 is the pressure applied to the air cylinder, A1 is the piston head cross-sectional area, and A2 is the operating oil pipe cross-sectional area.)

[0100] Meanwhile, the air booster unit (160) may further include a pressure control module (164).

[0101] The above pressure control module (164) is configured to include an operating oil pipe (163) and a pressure control valve for controlling the internal pressure, and the pressure control valve is installed through the tool body (110) so that the pressure inside the operating oil pipe (163) can be controlled from the outside of the tool body (110).

[0102] Meanwhile, the electric turret clamping device according to the present invention may be configured to further include an encoder unit (170).

[0103] Specifically, the encoder unit (170) can be installed at the rear of the main shaft (130).

[0104] More specifically, when the rotation of the main shaft (130) is detected even though the disk (120) is locked, the encoder unit (170) transmits a signal to the control unit provided externally, and the control unit generates inspection request information.

[0105] That is, the encoder unit (170) can be provided as a means to quickly detect wear of the clamping pad (153), wear of the catching protrusion of the cylindrical module (131), and damage to the air booster unit (160).

[0106] Suitable application examples of the electric turret clamping device according to the present invention as described above are as follows.

[0107] First, when the disk (120) rotates for indexing, it is in an unlocked state and the clamping pad (153) does not contact the cylindrical module (131), and the worm shaft (142) receives power from the driving unit to rotate the worm wheel (141). The main shaft (131) and the disk (120) rotate together with the worm wheel (141), and the rotational position is detected by the encoder unit (170).

[0108] Next, when the disk is locked for machining a workpiece, the self-locking state is maintained by stopping the worm shaft (142). Then, air pressure is applied to the inside of the air cylinder (161) of the air booster unit (160), the piston (162) moves forward, and the operating oil of the operating oil pipe (163) is pressurized and flows into the oil inlet space (152) of the clamping unit (150). The clamping pad (153) contacts and clamps the cylindrical module (131) due to the expansion of the oil inlet space (152), thereby maintaining the locking of the disk (120).

[0109] As described above, the electric turret clamping device according to the present invention is driven by an electric motor and can double lock the disk (120) to enhance the locking force.

[0110] Specifically, it includes a rotating part (140) of a self-locking long-barreled worm gear structure, and a clamping part (150) that strongly clamps the main shaft (130) with pressure transmitted from an air booster part (160) that amplifies and discharges air pressure, thereby ensuring strong locking force without installing a separate high-pressure hydraulic device through double locking.

[0111] The foregoing has broadly described the features and technical advantages of the present invention to better understand the scope of the claims. Those skilled in the art will appreciate that the present invention can be implemented in other specific forms without altering the technical spirit or essential characteristics thereof. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive. The scope of the present invention is indicated by the claims rather than the detailed description, and all changes or modifications derived from the claims and their equivalents should be construed as being included within the scope of the present invention.

Claims

1. Tool body; A main shaft extending forward and backward from the tool post body and rotatably installed with respect to the tool post body; A disk installed at the front end of the main shaft and rotating integrally with the main shaft; A rotating unit including a worm wheel fixedly installed on the outer surface of the main shaft at the rear of the above disk, having a worm gear screw thread formed on the outer surface and rotating integrally with the main shaft, and a worm shaft installed to mesh with the worm gear screw thread on the inside of the tool body and receiving power from the driving unit to rotate the worm wheel; A clamping unit including a housing fixedly installed in a tubular shape inside the tool body, the housing having an inner diameter larger than the outer diameter of the main shaft, an oil inlet space formed on the outer surface of the housing, and a clamping pad formed on the inner surface of the housing and in contact with the main shaft; An electric turret clamping device comprising an air booster unit, which is installed so as to be connected to an oil inlet space on one side of the tool body and has a shared pressure booster that amplifies the pressure of the applied air and supplies oil to the oil inlet space.

2. In paragraph 1, The above main shaft, An electric turret clamping device characterized in that a cylindrical module is installed with which the clamping pad of the above clamping part comes into contact.

3. In paragraph 2, The above clamping pad, An electric turret clamping device characterized in that protrusions are formed at regular intervals on the inner surface that comes into contact with the above cylindrical module.

4. In paragraph 2, The above cylindrical module, An electric turret clamping device further comprising a plurality of catches formed by protrusions arranged at regular intervals on an outer surface that comes into contact with the clamping pad.

5. In paragraph 1, The above air booster part, An air cylinder installed on one side of the inside of the tool body and having a piston that moves forward when air pressure is applied to the inside, An electric turret clamping device including an operating oil pipe filled with operating oil therein, one end of which is connected to the air cylinder, and the other end of which is connected to the oil inlet space.

6. In paragraph 1, The above rotating part, An electric turret clamping device characterized in that the worm shafts are provided in pairs and installed facing each other vertically with respect to the worm wheel.

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