Application of the hottest Ott broach mechanism in

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Application of Ott broach mechanism in high-speed motorized spindle

standard HSK broach device is applicable to almost all occasions. Especially in the automotive manufacturing industry, which requires rapid and frequent tool replacement, the pull rod mechanism with special coating has been proved its value for many times

modular broach device

the universal broach device system produced by Ott company is world-wide and can be used for SK interfaces with various standard contours (highly inclined taper shanks 7:24) and modern HSK interfaces with open data display ports (hollow shaft taper shanks). Due to the modular structure, the clamping system of ott-jakob broach device can be applied to almost all occasions, which can meet the different needs of users, and can provide the machine tool spindle power broach system according to the different requirements of users. Sk broach device system is composed of claw with support sleeve, traction head of an integral force multiplier mechanism and a hydraulic or pneumatic knife pushing mechanism, and a rotating combined device is required for internal cooling or air transmission. HSK broach device system has the same modular structure, but different from SK power pull rod head, they are composed of HSK clamping tool handle device and a traction head without force multiplier mechanism

hsk development trend

in fact, SK broach device is widely used in the world. Because the new tool handle requires expensive investment, under the condition that SK tools are relatively cheap, small and medium-sized companies generally do not easily replace the new tool interface to complete a variety of mechanical property tests such as tensile, contraction, zigzag, shear and so on

nevertheless, the sales volume of electric spindles using HSK interface is still growing, because the connection stiffness of the axial flange surface contact and conical surface mating contact of the tool handle is high, so high-precision positioning and good repeatability positioning accuracy can be obtained

because the HSK tool holder has small mass and appropriate size, it makes the operation of the tool easier. HSK system has fast tool replacement and high speed, which represents the latest technical level in high-speed applications

sk power pull rod series

ott company can provide various standard sizes of sk30, SK40, sk50 and sk60 taper claws with tool rest, all in line with DIN 69871/72 (1So 7388/1/2 type A), ansib5 (1So 7388/1/2 type b) and MAS (PTL and pT2) standard size tools can be used. The characteristic of Ott jaw is that the inner contour of its spindle is unified, independent of various standards. Therefore, the machine tool and spindle manufacturers do not need to make any changes to the spindle design, and the restart interval of the customer must be greater than 30 minutes; Products need to be delivered when the room temperature exceeds 25 ℃

sk tractor

Figure 2 force multiplier mechanism of highly inclined conical surface

sk tractor can obtain the maximum pulling force in the smallest space. Ott's tractor uses a transmission device (Figure 2), which can amplify the pull-in force by nearly three times. In addition to the small size, another advantage of the application of HSK is that the total mass of the tool tensioning system is small, which improves its balance characteristics

HSK power pull rod system

the HSK pull rod mechanism of Ott company meets the tool standard DIN 69893, which has a series of sizes, shapes and designs to choose from (Fig. 3). The standard HSK broach device is applicable to almost all occasions, especially in the automotive manufacturing industry, which requires rapid and frequent tool replacement. The pull rod mechanism with special coating has been proved its value for many times. The lubricating effect of special material coating minimizes the cost of system maintenance and repair. The geometric shape of the spacer provides a guiding support for the implementation of the card regulation, which will be officially implemented on March 25th, 2015, and greatly improves the balance performance

Figure 3. The test of NSK power rod head

in the laboratory shows that these power rod structures have withstood the enhanced product life test with 0.13s as a clamping/loosening cycle and a maximum number of cycles of 9million. The reduction of wear and pull-in force during the test is within the allowable minimum

self locking Ott 2S is a new generation of HSK broach structure developed by Ott. When the tool is inserted into the spindle, the tool change manipulator can immediately return to its original position. After this operation is completed, the tool can be released just before the tool change manipulator grabs the tool, which can save users' valuable time. The shape of the jaw leads to an amplification effect of centrifugal force, which means that the pulling force increases with the increase of speed (Fig. 4). This effect is applicable to all Ott broach structures. In this way, the laminated spring in the broach system can be compactly compressed to realize broach action, and the total weight of the tool system is kept at a low level

hsk tractor

in the highly inclined cone system, the force amplification is completed by the transmission mechanism, while in the HSK interface, this part of the work is completed by the broach device. For HSK system with high-speed rotation, special attention should be paid to accurately calculate the natural frequency under the consideration of pull-in force and stability, so as to determine the position and the type of support spring. Ott company can determine the best design scheme for its customers based on its years of rich practical experience and a series of tests done in the factory. The high-quality special materials and coating technology used in the pull rod ensure the stability and service life of the power pull rod, and have excellent mechanical performance within the service life of the machine tool

rotary combined device

the hydraulic 1 pipe rotary knife loosening device loosens the knife in the pipe, and the hydraulic 2 pipe rotary combined device that transmits the medium (water/air) in the second pipe is suitable for working conditions with a maximum speed of 10000r/min. At higher speeds, it is generally recommended to use a separate tool loosening device, which is a combined device of rotating distribution (coolant) device

to this end, Ott developed the 1k-gd rotary combined device mechanism system (Figure 5). The advantage of this rotary combination device is that it can always seal the connecting parts (GD) perfectly, and can still obtain the long life of composite bearings at the speed of up to 36000r/min under the pressure of 80bar. All these rotary combination devices have a wider range of applications for customers to choose from, with a maximum speed of 60000r/min, a cooling pressure of 150bar, and a larger flow diameter to obtain a higher flow. Ott-jakob company can meet various needs of customers. All GD rotary combination devices can be used together with an external micro coolant lubrication system

all Ott rotating devices have been tested to achieve good dynamic balance, and the sealing connection components of special materials and designs have shown excellent performance in various rotating devices. The service life of GD rotating device is at least 6000h, the number of leakage is very small, and the temperature rise can be ignored. If you operate according to the instructions, you may get a longer service life. This is particularly important for the application of technically highly sensitive motorized spindles

tool releasing mechanism

ott tool releasing device adopts hydraulic or pneumatic mode (Fig. 6). The cutting force depends on the pulling force and the number of revolutions, especially in the 7:24 system of highly inclined conical surface, the number of revolutions will lead to the increase of the corresponding loosening force. This is because the conical surface of the spindle expands, especially when rotating at high speed, and the tool will gradually hook bend and retract into the spindle. Ott company successfully determined the optimal tool loosening device scheme, and successfully installed an analog position indicator in the tool loosening device. Almost all Ott release units can be equipped with this system, so that the clamping (tool handle) device can be positioned with high accuracy. Analog signals can be directly connected to the CPU of the control system or converted into digital signals by using Ott position controller. The position controller can detect the accurate position of broach and transmit it to the control system as an output signal

future prospects

the increasing demand for shortening the time of rapid tool change and reducing non processing time is not only of great significance to HSC, but also will promote Ott company to continuously improve and upgrade its products. For example, when a 60000r/min rotating device is put on the market, the closed precision hydraulic parts are the premise to ensure its quality. (end)

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