2017年8月31日星期四

Milling machine milling amount selection

Selection of milling machine milling amount, first selection of back cutting depth and side cutting depth is bigger, then choose the feed per tooth larger, and finally determine the milling speed.
(1) Cutting depth
The cutting depth is selected according to the machining allowance, the machined surface quality and the milling machine power.
When the power and rigidity of the machine are allowed, it is usually economical to cut all the machining margins with one feed.
For the cylindrical milling cutter, the cutting depth is side cutting depth. For face milling cutter, the cutting depth is back cutting depth.When the processing margin is less than 5~6mm, a knife can be milled all the processing margin; if the processing margin is greater than 5mm, size accuracy requirements are high, can be divided into thick, fine two pass, the second time Knife to take 0.5~1mm.
(2) Feed amount
Feed amount is based on the workpiece surface roughness, processing accuracy and cutting tools, milling machines, fixtures and other factors determined by the stiffness. Usually the following data can be used: high-speed steel cylindrical cutter, processing ordinary steel can take fz= 0.04~0.15mm; processing cast iron desirable fz= 0.06~0.5mm. High-speed steel milling cutter, processing ordinary steel is desirable fz= 0.04~0.3mm; processing cast iron desirable fz= 0.06~0.5mm. Carbide end mills and three blade milling cutter processing steel and cast iron, desirable fz =0.08~ 0.3mm.
After the fz value is determined, the feed rate can be calculated and the approximate value is selected by the value provided by the milling machine.
(3) Cutting speed
The cutting speed is determined by factors such as the material of the workpiece and the tool, the amount of cutting, the geometry of the tool teeth, and the durability of the tool. Usually can be found from the manual, or calculated by the empirical formula.
When milling steel with a carbide cutter, the milling speed is 3~5m/s; Milling speed up to 6~10m/s; milling cast iron, improve the milling speed on the surface quality improvement is not significant, so the milling speed is lower. With high-speed steel cylindrical milling cutter milling, the milling speed is generally 0.3~1m/s.
According to the selected milling speed, converted into the corresponding number of revolutions, and then press the milling machine marked on the speed selected.

2017年8月30日星期三

Milling machine milling amount

Milling amount is very important for milling machine. Today we talk about it.
1. The basic movement of milling
When milling, the relative movement of the workpiece and the milling cutter is called milling movement. It includes the main movement and feed movement. The main movement is the rotation of the milling cutter; the feed movement is the movement of the workpiece or the rotation of the cutter.
2. Milling amount
The main elements of the milling amount are milling speed vc, feed speed vf, back cutting depth ap and side cutting depth ae, as shown in the figure.
(1) Milling speed
Milling speed is the speed of the selected point on the milling tool relative to the main movement of the workpiece. The milling speed is related to the cutter diameter and the cutter speed. When milling, according to the milling of the workpiece material, milling cutter material and other factors to determine the milling speed, and then according to the milling cutter specifications (diameter) to calculate and determine the milling machine spindle speed.
(2) Feed motion parameters
According to the specific circumstances, there are three ways of expressing and measuring the amount of feed in milling.
①Each turn feed f. The amount of movement of the cutter relative to the workpiece in the direction of the feed movement per revolution.
②Each tooth into the amount of fz. Each turn of the milling cutter, a cutter tooth moves relative to the workpiece in the direction of the feed motion.
③Feeding speed vf. The amount of movement of the cutter relative to the workpiece in each direction of the feed 1min in the direction of feed motion. The relationship between the three feeds is
In the formula, n is the milling cutter or milling machine spindle speed; Z is the number of milling cutter teeth.
At the time of milling, the feed rate fz is determined according to the machining properties. Then, the feed rate vf is calculated based on the number of teeth Z of the milling cutter and the rotational speed n of the milling cutter, and the milling machine feed rate is adjusted accordingly.
(3) Back cutting depth
Refers to the size of the milling layer measured parallel to the axis of the milling cutter.
(4) Side cutting depth
Refers to the size of the milling layer measured in the direction perpendicular to the axis of the milling cutter.

2017年8月29日星期二

Milling machine workpiece clamping

There are many ways to clamp the workpiece on the milling machine. Let's start by saying how to use the flat nose clamps and the press plate to hold the workpiece.
1. The workpiece is clamped on the flat nose clamps
(1) The clamping of blank pieces. Select a large plane on the blank as a rough datum, which rests against a fixed jaw or guide surface. In the jaw or guide surface and the workpiece between the rough surface of copper pad, to prevent damage to the jaws. First light grip the workpiece, with a dial to correct the rough plane position, the basic parallel and then clamping the workpiece.
(2) The clamping of the workpiece after the roughing. Select a larger rough surface on the workpiece as a reference plane, it will be fixed to the fixed jaw or clamp body surface for clamping. When the workpiece base is facing the fixed jaw face, a round bar can be placed between the movable jaw and the workpiece in the middle of the height of the jaws holding the part of the workpiece. Through the round bar clamping the workpiece, to ensure that the workpiece reference plane and fixed jaw face a good fit.
When the reference surface of the workpiece is against the rail surface of the clamp body, a parallel horn is provided between the workpiece and the guide rail. In order to make the workpiece reference plane parallel to the guide surface, after clamping with a copper hammer blow the upper surface of the workpiece, and hand to try to horn, to loose is appropriate. This shows that the workpiece is well fitted with the horn and then clamped. When the workpiece is clamped with a flattened clamp, the placement of the workpiece should be appropriate. The clamping force of the workpiece should be evenly equal. After cutting the allowance, the working surface should be 5 ~ 10mm higher than the plane of the jaws.
2. Clamp the workpiece with the press plate
Shape, large size or not easy to use flat nose clamps clip of the workpiece, commonly used press plate in the milling machine table for processing. The workpiece is clamped with the press plate, and the method of milling with face milling cutter in horizontal milling machine is widely used.
There are many kinds of press plate shape, can adapt to a variety of different shapes of workpiece clamping needs. In the milling machine with a press plate clamping workpieces, mainly press plate, horn, T-bolts (T-nuts) and nuts. When clamping the workpiece with a press plate, two or more platens should be selected. One end of the platen shall be on the workpiece and the other end on the horn. The height of the horn shall be equal to or slightly higher than the height of the workpiece to be pressed. And the distance between the workpiece should be as short as possible. When using the press plate, there should be a gasket between the nut and the platen.

2017年8月28日星期一

Milling machine flat nose clamp

The flat nose clamp is an accessory used to clamp the workpiece on the milling machine. Milling the rectangular box of the general rectangular parallelepiped, the step surface, the slope and the shaft of the workpiece, can be clamped with a flattened clamp.
1. The structure of a flat nose clamp
Commonly used flat nose clamps are both rotary and non-rotary.The clamp body of the rotary flattened clamps can be rotated at any angle on the base. Non-rotary flat-nose clamp structure and rotary flat-nose clamp is basically the same, but the base does not have a turntable, clamp body fixed. Rotary flat nose clamps easy to use, adaptable, but because of a layer of turntable structure, height increases, the relative reduction in rigidity. Therefore, in the milling plane, vertical and parallel plane, the general use of non-rotary flat clamp.
2. Installation and correction of flat nose clamps
(1) The installation of flat nose clamp. When installing the flat clamp, wipe the bottom of the clamp base and the work surface. The flat nose clamp is installed in the center of the length of the center of the table, the center of the width direction, to facilitate the operation. In rough and semi-finished milling. Make the milling force point to the fixed jaws. As shown in the figure.
When machining the general workpiece, the flat nose clamp can be installed with the positioning key. When installing, place the positioning key on the base of the flat clamp into the center T-slot of the table and push the clamps with both hands so that the same side of the two positioning keys rest on the same side of the central T-slot, and then secure the clamp. Use the zero mark on the clamp to match the engraved line on the base, turn the clamp body so that the fixed jaws are perpendicular or parallel to the milling machine's main axis, or you can adjust the angle as needed.
(2) correction of flat jaws. Correct the jaws with a dial indicator to ensure vertical or parallelism with the spindle axis of the milling machine as shown.
①Correct the fixed jaw and milling machine spindle axis perpendicularity. Calibration, the magnetic table seat adsorption on the beam guide surface, install the dial indicator, so that the table measuring rod and fixed jaw iron plane perpendicular.
With a clamp iron flat compression rod contacts about 0.1~0.2mm, vertical movement of the table, record the dial indicator. The difference between the maximum reading and the minimum reading is the value that the fixed jaws need to rotate in the small direction. Rotating fixed jaws, and re-examination, re-qualified, fastened clamp body.
②Correct fixed jaw and milling machine spindle axis parallelism. When correcting the jaws parallel to the milling machine spindle axis. The magnetic table can be sucked on the bed vertical guide surface, horizontal movement of the table, the correction method Ibid.

2017年8月27日星期日

Milling machine cutter installation

The correct installation of the milling cutter directly affects the milling machine to proceed smoothly, so it should be given sufficient attention.

As shown in the figure, the milling cutter is mounted as close as possible to the end of the spindle to increase the rigidity of the process system and reduce vibration. When installing the cutter on the milling machine, wipe the positioning sleeve and the milling cutter to reduce the end of the milling cutter. Insert the arbor into the spindle taper hole and align the keyway on the arbor with the key on the spindle. The rod and the handle rod thread screwing at least 5 to 6 pitch; in the tighten the nut on the cutter before the need to install the pylons, and finally the arbor and the spindle, cutter and knife pole in close cooperation.
Milling cutter loading and unloading precautions
1) When installing a cylindrical cutter or other perforated milling cutter on the milling machine, fasten the hanger and tighten the cutter. Disassemble should first release the cutter, then release the rack.
2) Loading and unloading milling cutter, cylindrical milling cutter with both ends of the hand; when loading and unloading the end milling cutter, the hand is covered with cotton yarn to hold the circumference.
3) When installing the milling cutter, the contact surfaces shall be wiped to prevent the dirt on the contact surface from affecting the installation accuracy.
4) Tighten the length of the thread on the screw should be with the milling rod or cutter on the screw hole has enough rotation length.
5) The hanger bearing hole and the milling rod support shaft should maintain a sufficient mating length.
6) Milling machine cutter should be installed after installation check is correct.

Milling machine cutter

Milling cutters are one of the indispensable tools for milling machine. Only by choosing the right milling cutter, can the ideal machining result be achieved.
1. Milling cutter material
1) High-speed tool steel has good cutting performance, the appropriate cutting speed of 16 ~ 35 m/min. Used in the manufacture of more complex shape of the cutter.
2) Carbide steel has good wear resistance, poor cutting performance at low speed and poor manufacturability. Cutting speed is 4~7 times higher than that of high speed tool steel. Milling machine cutting tools for high speed cutting and hard material cutting. Usually, the carbide blade is fixed on the cutter body by welding or mechanical clamping.
The cutter is essentially a multi-blade standard tool consisting of several single-blade tools whose main and secondary cutting edges are distributed on the outer or outer surface according to their type and structure.
2. Milling cutter classification
There are many ways to classify milling machine cutters. According to the milling cutter installation method is divided into two kinds of hole milling cutter and handle milling cutter.
The common hole milling cutters are cylindrical milling cutter, three face milling cutter (integral or inlaid type), saw blade milling cutter, modulus milling cutter, angle milling cutter and arc milling cutter (convex arc or concave arc) and so on. The milling cutters with holes are used in horizontal milling machines for machining flat surfaces, straight grooves, cuts, teeth and arc grooves (or spiral grooves).
Handle milling cutter according to the shape of the handle is divided into two kinds of straight handle or taper shank. Commonly have a tooth face (end) cutter, end mills, keyway cutter, T-slot cutter and dovetail slot cutter, as shown. Handle Mills are used in vertical milling machines for machining flat, stepped surfaces, grooves and keyways, T-slots or dovetail slots.

2017年8月25日星期五

Milling machine main components

We take the X6132 horizontal universal milling machine as an example to introduce the main components of the milling machine and its function. As the picture shows.
(1) Spindle speed change mechanism
Spindle speed mechanism installed in the bed, its role is to change the speed of the motor through the gears, into 18 different speed, passed to the spindle to meet the milling requirements of various speeds.
(2) Bed
The bed is the main body of the milling machine, used to install and connect other parts of the machine. The front of the bed has a vertical guide, the table can be along the rail, the next move. The top of the bed has a dovetail horizontal guide, the beam can be along the top of the bed dovetail guide horizontal movement. The interior of the bed is equipped with spindle mechanism and spindle speed change mechanism.
(3) Cross beam
The crossbeam can be provided with a hanging rack and move along the dovetail guide rail at the top of the bed.
(4) Spindle
The spindle is used to realize the main movement, is the front end of the hollow shaft with taper hole, milling cutter rod and cutter for installation. The spindle is driven by a transmission mechanism and rotates along with the milling cutter.
(5) Hanging rack
One end of the milling cutter rod mounted on the spindle taper hole, the outer end is installed on the rack, in order to enhance the rigidity of the cutter bar.
(6) Workbench
Used to install the workpiece or milling machine fixture, driven workpiece to achieve longitudinal feed movement.
(7) Horizontal slide plate
Used to drive the milling machine table to achieve horizontal feed movement. There is a rotary disc between the horizontal slide plate and the table, which allows the table to rotate within ±45°in the horizontal plane.
(8) Lift
Used to support the horizontal slide plate and table, driven on the table, move down. The elevator is equipped with a feed motor and a feed mechanism.
(9) Feeding speed change mechanism
Used to adjust and transform the feed speed of the table to meet the needs of milling.
(10) Base
Used to support the bed, to support the milling machine all the weight, loaded with cutting fluid.

2017年8月24日星期四

Milling machine processing range

Milling of metal materials is one of the most commonly used machining methods in machining. Milling is the use of milling cutter in the milling machine to remove part of the balance, access to a certain dimensional accuracy, surface shape and position accuracy, surface roughness requirements of the processing method.
It has a wide range of processing, high production efficiency, the economic processing tolerance level is generally IT9 ~ IT7, surface roughness 12.5 ~ 1.6um. Therefore, the milling process in the machine manufacturing industry has an important position.
Common milling machines:
(1) Horizontal lift milling machine
Horizontal lift milling machine has a vertical movement along the bed of the lifting platform, the table can be vertical and vertical movements with the lift, the elevator can be used for vertical and horizontal movement; machine spindle and table parallel to the table. This machine is easy to use, suitable for processing small and medium parts. Typical horizontal lift milling machine model for the X6132.
(2) Vertical lift milling machine
The main difference between the vertical lift milling machine and the horizontal lift milling machine is that the spindle of the machine is perpendicular to the table. Typical vertical lift milling machine model for the X5032.
(3) Universal tool milling machine
Universal tool milling machine has a horizontal spindle and vertical spindle, the table for vertical and vertical movement, horizontal movement by the spindle to achieve. This machine can complete a variety of milling work, widely used, especially suitable for processing a variety of fixtures, tools, tools, molds and small complex parts. Typical universal tool milling machine model X8126.
(4) Gantry milling machine
Gantry milling machine is a large machine tool, milling power installed in the gantry rails, a vertical spindle box and horizontal spindle box, for horizontal and lifting movements. The table is placed directly on the bed, heavy load, can be processed heavy parts, but only for vertical movement. Typical gantry milling machine model for the X2010.

2017年8月23日星期三

Milling machine universal milling head's function

In the horizontal milling machine installed on the universal milling head, not only to complete a variety of vertical milling work, but also according to the needs of milling, the milling head spindle at any angle.
Figure (a) for the universal milling head (the milling cutter 2 into a vertical position) of the outline. The base 1 is bolted to the vertical guide of the milling machine. The movement of the spindle is transmitted to the milling head spindle by two pairs of bevel gears in the milling head. The housing 3 of the milling head can be deflected at any angle (Figure b) around the axis of the milling machine spindle. The housing 4 of the milling head spindle can also be deflected at any angle on the housing 3 (Figure c). Therefore, the milling head spindle can be deflected in space to any desired angle.
Universal milling head in the mechanical processing has played a great role,  In the actual production in order to achieve a special angle processing, we developed a 360°rotation of the milling machine universal milling head. It not only has a greater cutting capacity, but also can be processed Any angle of the special workpiece.

Milling machine processing spiral groove

In the universal lift milling machine, with the universal dividing head milling spiral groove, the following adjustment should be carried out.
(1) The workpiece is held on the top of the dividing head spindle and is supported by the top of the tailstock, and the table is deflected about the vertical axis so that the milling machine is in the same direction as the spiral groove of the workpiece. The direction of deflection of the milling machine table is determined by the helical direction of the helical groove.

(2) Between the table vertical feed screw and the dividing head spindle, with the exchange of hanging wheel Z1, Z2, Z3 and Z4 link, when the table and the workpiece along the workpiece axis direction, will pass through the wire Bar, with gear and sub-head drive, driving the workpiece for the corresponding rotary motion.
The guide of the helical groove of the workpiece is T. Milling machine longitudinal feed screw lead for the Ts table and the workpiece to move a lead T distance, that is, when the vertical screw to T / Ts, the workpiece should be a turn. At this time the workpiece can be cut by the cutter cutter lead for the spiral groove T.
According to the drive system diagram, motion balance can be listed:

Simplify and replace the formula:
Formula Ts for the milling machine table vertical feed screw lead; T for the workpiece spiral groove lead.
For sub-tooth parts (such as helical gears, helical cutter, twist drill, etc.), after each processing a tooth groove, the workpiece should be removed from the processing position, pull out the pin J so that the dividing head spindle and longitudinal feed screw broken movement contact, and then use the simple dividing method to divide the workpiece.

Milling machine milling method

When machining workpieces on a milling machine, we often use reverse milling and milling two methods.When the feed direction of the workpiece is opposite to the cutting speed of the cylindrical milling cutter, it is called reverse milling. When the feed direction of the workpiece is the same as the cutting speed of the cylindrical milling cutter, it is called milling.
Milling is conducive to improving the durability of the tool and the stability of the workpiece clamping, but easy to cause the table to move, and even cause accidents. Therefore, the milling machine should have a means to eliminate the gap between the screw and the nut, and the milling range should be limited to the non-crusty workpiece. In the fine processing, the milling force is small, difficult to cause the table of the channeling, and more use of milling. Because the milling does not slip phenomenon, the surface quality after processing is better.
When milling, the milling cutter always has a downward force to compress the workpiece, making the milling smooth. The cutting thickness of each knife is reduced from the maximum to zero, easy to cut into the workpiece, and cut out when the working surface of the extrusion friction is also small, slower blade wear, processing surface quality is higher. The power consumed in the direction of the feed movement is small. The cutting edge is cut from the outer surface of the workpiece, and the blade is easy to wear and damage when the workpiece is crusty with crust and impurities. Milling cutter on the workpiece's horizontal component and feed the same direction, it will pull the table, when the screw and nut, bearing the axial clearance is large, the table is pulled will make the cutter per tooth feed suddenly increased Large, causing the teeth to break, knife shaft bending, workpiece and fixture movement, and even damage the milling machine.
Reverse milling is used for roughing, processing of crusty castings, forging blanks and so on. In the case of milling machines without screw nut adjustment mechanism, reverse milling should also be used. In the case of reverse milling, since the cutting edge is not cut from the outer surface of the workpiece, the workpiece has a hard skin on the milling surface and has little effect on the damage to the blade. However, the cutting thickness of each blade is increased from zero to the maximum, As the edge of the knife teeth always have a certain arc, so the knife teeth contact the workpiece after a distance to cut the workpiece, the blade easy to wear, and the machined surface by the extrusion and friction, affecting the quality of the surface processing.
When reverse milling, the horizontal component and the workpiece feed the opposite direction, will not pull the table, screw and nut, the bearing is always kept in close contact without loosening, but reverse milling will produce upward vertical force, so that the workpiece has a rising trend.Therefore, must make the workpiece clamp firmly, and the vertical component in the cutting process is changing, easy to produce vibration, affecting the workpiece surface roughness. In the reverse direction, the power consumed in the feed direction is large.
Understand the milling machine two different milling methods, select the appropriate milling method, in order to achieve the best processing results.

2017年8月21日星期一

Milling machine differential dividing method

As the milling machine dividing disc with holes limited, some of the division number because there is no suitable hole ring, and can not be simple dividing method, such as 73, 83, 113 and so on. At this point the differential dividing method can be used.
Using differential dividing, should loosen locking screws, the dividing plate can be driven bevel gear rotary milling machine, and the dividing spindle taper hole arranged in the back-end transmission shaft, the change gear of a, b, c, d and Axis II connection (Figure).
Differential working principle is as follows: Set the workpiece requirements for the degree of Z, and Z> 40, then the indexing spindle should be transferred to each 1 / Z turn. At this time, the handle should still turn 40 / Z turn, that is, the pin should be transferred from point A to point C. With the C point positioning, but the dividing plate at the C there is no corresponding hole for the identification of the location, and thus can not be used to achieve a small degree of sub-indexing. In order to use the milling machine on the dial circle, select Z0 to calculate the number of revolutions of the handle, the handle turns 40 / Z0 turn, that is, the switch from A to B, with B point positioning. At this time if the dividing disc is fixed, the handle turns 40 / Z0 instead of the required 40 / Z turn, there is a difference between the two. To compensate for this difference, turn the hole at point B to point C for pin positioning. To this end, the gears can be used to connect the milling machine to the dividing head spindle and the dividing plate. During the dividing process, when the latch is moved from point A to point C, the dividing plate is rotated by a number equal to the difference making the hole is just aligned with the latch.
Motion balance:

Simplification has to replace the formula:
In order to facilitate the use of replacement gear Z0 should be selected close to Z (can be greater than or less than Z) and 40 with a common factor value.
When Z0> Z is selected, the direction of rotation of the handle and the dial should be the same, and the gear ratio is positive.
When Z0 <Z is selected, the direction of rotation of the handle and the dial should be reversed, and the gear ratio is negative.
FW125 type milling machine dividing head with a module with a gear number of 1.75mm or less:24(two),28,32,40,44,48,56,64,72,80,84,96,100, A total of 15.

2017年8月20日星期日

Milling Machine Simple Dividing Method

When the number of divisions is large, you can use a simple dividing method of milling machine. Before the dividing, engage the worm and the worm gear, fix the dividing plate 7 with the locking screw 9 so that it can not be rotated and adjust the latch J to align it with the hole of the selected dividing plate.
When dividing, pull out the latch J, turn the handle K, drive the dividing the head spindle to the desired dividing position, and then reinsert the plug into the dividing hole.
Set the workpiece to be equal to the score Z, that is, each time the division of the head of the spindle should be turned 1 / Z turn. By the transmission system can be seen, the handle each time the degree of rotation should be:
The above formula can be written as follow
(q is the number of holes in the selected hole; p is the number of holes that the pin 10 should turn over the hole of the q hole.)
Example: In the FW125 milling machine division head on the dividing, the degree of division Z = 32;
solution:
The fraction in the upper form is simplified into the simplest integer, which is 1 / 4, and then the numerator and denominator are multiplied by the same integer, so that the denominator is the number of holes in the hole, 16 or 24, 36, etc. on the dial.In this case, the dividing handle should be turned one full turn, then turn the 4 hole spacing between the 16 holes, or turn the 6 holes apart on the 24 hole.
To ensure that the dividing is correct, the angle of the dividing fork 5 should be adjusted so that its inner edge contains (p + 1) holes in the holes of the q holes so that the identification pin 10 should be turned the hole spacing, to prevent the operation of the error. The above is the simple dividing method of milling machine.

Milling machine dividing head

In the use of milling machine for processing, we often encounter milling hexagonal, gear, spline and engraved line and so on. At this time, the workpiece after each milling or - slot, you need to turn an angle, and then milling the second side, the second slot and so on. This work is called dividing. Dividing head is based on processing needs, the workpiece in the horizontal, vertical and tilt the location of the organization. One of the most common is the universal dividing head.
1. The use of the universal dividing head
Lift table milling machine is equipped with a variety of accessories, used to expand the scope of technology, including universal dividing head is a commonly used accessories. The machined workpieces are mounted on the top or chuck of the universal dividing head spindle and can be operated as follows:
①the workpiece around the axis of a certain degree of rotation to complete the equal or unequal circle indexing work. Such as processing square head, hexagonal head, gear, sprocket and unequal knife reamer and so on.
②through the replacement gear, by the dividing head drive the workpiece continuous rotation, and milling machine table with the vertical feed movement, can be processed spiral groove, helical gear and Archimedes spiral cam.
③holding the workpiece with a chuck, so that the workpiece axis relative to the milling machine table tilted a required angle, for processing and the workpiece axis intersect a certain angle of the groove or plane.
2.The construction of the universal dividing head
The following to FW125 universal dividing head as an example, indicating the structure and adjustment method of the milling machine dividing head. In the figure, the dividing head spindle 2 is mounted in the drum-shaped casing 4, which is supported on both sides by a journal on both sides and rotatable about its axis so that the spindle is adjusted to a desired angle within a range of 95°above the horizontal line The The front end of the dividing head has a taper hole for the installation of the top 1, with a bit of a pyramid on the outside for the installation of a three-jaw chuck.
Turn the dividing handle K, the transmission ratio u = 1/40 worm gear pair, driven by the dividing head spindle to the desired dividing position.The number of revolutions of the dividing handle K at the indexing is determined by the number of holes in the perforations of the dividing plate 7 by the latch J. These holes are distributed on the concentric circles with equal number of holes on the end of the dividing disc. FW125 universal dividing head with three sub-dial, for the selection of sub-degree, each sub-plate has 8 holes, the number of holes per hole were:
    the first     16、24、30、36、41、47、57、59
    the second  23、25、28、33、39、43、51、61
    the third    22、27、29、31、37、49、53、63

2017年8月18日星期五

Milling machine table horizontal and vertical feed control mechanism

The horizontal and vertical feed control mechanism of the X6132 milling machine table is shown in the figure. Handle 1 has upper, lower, front, rear and middle five working positions. When the handle 1 is moved forward and backward, the drum is driven by the ball at the front of the handle to move left and right axially. When the handle 1 is moved up and down, the drum 9 is rotated back and forth within a certain range by the flat groove on the hub body 3, the flat key 2 and the shaft 4.

On the circumference of the drum 9, the grooves with bevels control the micro switches SQ3, SQ4, SQ7 and SQ8, respectively. Where SQ8 is used to control the opening or disconnection of the electromagnetic clutch M5, which is used to turn on or off the electromagnetic clutch M4, i.e., to turn on or off the vertical feed motion and the lateral feed motion, respectively. SQ3, SQ4 is used to control the forward and reverse rotation of the feed motor, so that the milling machine table is moved forward, down and backward.
When the handle 1 is pulled forward, the drum 9 is moved axially to the left, and the bevel on the drum presses the lower pin 7 and acts on the microswitch SQ3 to turn the feed motor forward. At the same time, the pin 5 on the drum circumference, acting on the microswitch SQ7, so that the lateral feed electromagnetic clutch M4 through the power to work, so as to achieve the milling machine table forward horizontal feed movement.
When the handle 1 is pulled back, the drum 9 is moved axially to the right, the bevel on the drum presses the lower pin 8, acts on the microswitch SQ4, reverses the feed motor; the pin 5 is still in the drum round on the circle, so that the electromagnetic clutch M4 through the work of compact, to achieve the back of the table horizontal feed movement.


When the handle 1 is moved to the upper position, the drum 9 is rotated in the counterclockwise direction, and the inclined surface thereon is pressed against the pin 8 to act on the microswitch SQ4 to reverse the feed motor; the pin 6 is on the drum circumference , the lower pin 6 is pressed and acted on the microswitch SQ8 so that the electromagnetic clutch M3 is energized and pressed to achieve the upward movement of the milling machine table.
When the handle 1 is pulled down, the drum 9 is rotated in the clockwise direction, and the inclined surface thereon is pressed against the pin 7 to act on the microswitch SQ3 so that the feed motor is rotated forward; the pin 6 on the drum circumference is pressed, so that the micro-switch SQ8 work, so that the electromagnetic clutch M3 power on the work, to achieve the milling machine table down the feed movement.
When the handle 1 is pulled to the middle position, the top pins 8 and 7 are in the groove of the drum, the freckers SQ4 and SQ3 are released, the feed motor stops rotating, and the pins 5 and 6 are also in the drum slot, release the micro switch SQ7, SQ8, so that the electromagnetic clutch M4 and M3 power off, so the milling machine table front and rear feed movement and the upper and lower feed all stop.

2017年8月17日星期四

Milling machine table longitudinal control mechanism

The longitudinal feed control mechanism of the X6132 milling machine table is shown in the figure.

The longitudinal feed movement of the table is controlled by the handle 23, and the microswitch SQ1 or SQ2 is pressed while the end face clutch M5 is turned on or off, so that the feed motor is rotated forward or backward to effect operation the vertical or leftward longitudinal movement of the table. The shaft 6 is provided with a spring 7 and a fork 5 for urging the clutch M5, and the force of the spring 7 causes the shaft 6 to move leftward to drive the fork 5 to the left by the clutch M5; the longitudinal feed movement of the table , But also by the other side of the milling machine to manipulate the handle, pull the handle, the lever, pendulum on the pin 10, the lower end of the fork 9 so that the bump 2, the next swing.

When the handle 23 is pulled to the left, the pressing block 16 is swung to the left, the microswitch 22 (SQ2) is pressed, and the fork 14 is rotated clockwise while the feed motor is rotated in the opposite direction. The sleeve 2 is pivoted clockwise by means of a screw and the swing block 11 so that the projection 2 also oscillates clockwise and the highest point of the projection 2 leaves the left end face of the shaft 6, Under the action of the spring 7, the shaft 6 is moved leftward to drive the fork 5 to the left and the clutch M5 is turned on to realize the longitudinal feed movement of the milling machine table to the left.
When the handle 23 is pulled from the left to the neutral position, the presser 16 loosens the jog switch 22 (SQ2) and the feed motor stops rotating; and the projection 2 oscillates counterclockwise and its highest point pushes the shaft 6 to the right , The clutch M5 is disengaged by the fork 5, and the longitudinal feed movement to the left is stopped.
Similarly, when the handle 23 is pulled from the left to the right position, the pressing block 16 presses the microswitch 17 (SQ1), and the feed motor rotates forward. At the same time, since the projection 2 is swung counterclockwise, the highest point is left The left end face of the shaft 6 is turned on again by the spring 7 clutch M5, thereby effecting the milling machine table to the right longitudinal feed movement.

2017年8月4日星期五

Milling Machine Table

First of all, let's look at the structure of milling machine table. The vertical feeding and rapid movement of the worktable of the lifting table milling machine are usually driven by screw and nut pairs.
The table structure of the X6132 milling machine is shown in figure. It is composed of the worktable 7, the bed saddle 1 and the rotating disk 3.
The bed saddle 1 uses its rectangular guide to engage the rails of the lift to move the table horizontally on the platform rail. When the table is not moved horizontally, the saddle can be clamped to the lifting table by the action of the eccentric shaft 12 by the handle 13. The table 7 can be moved longitudinally along the dovetail rail above the rotating disk 3. The milling machine table, together with the turntable, can be rotated about -45 °to 45 °about the axis Ⅷ of the bevel gear and fastened to the saddle using bolts 14 and two arc press plates 2.
The longitudinal feed screw 4 is supported on the sliding bearing at the left front bracket 6 of the table and the thrust ball bearing and the tapered roller bearing at the right rear rear bracket 10 of the table to bear the radial force and the axial force in both directions.The clearance of the bearing is adjusted by nut 11. The handwheel 5 is sleeved on the lead screw 4, and when the handwheel 5 is pushed inward and the compression spring is applied to the end face clutch M, the manual milling machine table can be moved longitudinally. On the rotary disc 3, the clutch M5 is splined with the spline sleeve 9 and the spline sleeve 9 is connected to the longitudinal feed screw 4 having the keyway by the slide key 8, so that the end face tooth clutch M5 is turned on to the left, the movement from the shaft XVIII is driven by the bevel gear pair, M5 and the slider 8 to drive the longitudinal feed screw 4 to rotate. Since the double nut is fixedly mounted on the left end of the turntable, it can neither rotate nor move axially. Therefore, when the longitudinal feed screw 4 is subjected to the rotary movement, it is moved axially at the same time, so that the table 7 is moved in the longitudinal direction or moved rapidly.
Through the above description, I believe you have a clearer understanding of the structure of the milling machine table.

2017年8月3日星期四

Milling Machine Speed Change Mechanism

The main movement and feed movement of X6132 milling machine are controlled by the hole plate speed change control mechanism. The following we take the main speed control mechanism as an example to explain its working principle.
As shown in the figure is the use of hole plate speed control mechanism control triple slip gear schematic. Milling machine hole plate speed control mechanism mainly by the hole plate 4, the rack shaft 2 and 2 ', gear 3 and fork 1 composition.
The hole plate 4 is divided into several groups with different diameters, and each circumference is divided into 18 equal parts. According to the requirements of the gears at different positions during the gear change, the 18 positions are divided into three states: drilling big hole, drilling small hole or no drilling. The rack shafts 2 and 2'are machined with two rows of shoulder diameters of D and d respectively. The shoulder diameter of the d can pass through the holes on the orifice, and the shoulder diameter of D can pass through the big holes on the hole plate. Speed change, the first plate to the right shift, so that it back off the rack axis, and then according to the requirements of speed change, turn the disc to a certain angle, then make the hole plate left shift reset. When the hole plate is reset, the sliding gear can obtain three different positions through the big holes, the small holes or the non holes of the hole plate, so as to achieve the purpose of the speed change of the milling machine.Three working states are:
①The position of the corresponding rack shaft 2 on the hole plate is without hole, and the position corresponding to the rack shaft 2'is a big hole, and when the hole plate is reset, the left and top rack shaft 2 is pushed, and the triple sliding gear is pushed to the left position by the shifting fork. The rack shaft 2'moves right under the combined action of the rack shaft 2 and the pinion 3, and the shoulder D passes through the large hole on the hole plate;②The two holes are small holes, the small shoulder D of the rack shaft passes through the small holes on the hole plate, and the two rack shafts are in the middle position, so that the sliding gear is in the middle position by shifting the fork;③The hole plate corresponding to the rack shaft
2 position for large holes corresponding to the rack shaft 2'position without holes, the hole plate top rack shaft 2' left, and 3 to 2 through the gear rack shaft shoulder through hole right, and the gear is in the right place.
The structure of the main control mechanism is shown in the figure. It is an independent component mounted on the left side of the bed column of the milling machine and is operated by the handle 1 and the speed plate 10 for variable speed operation.When changing the rotational speed,the handle 1 is pulled out, the handle 1 by a pin 2 for rotation center, disengaged from the positioning pin 3 on the handle groove position; then counterclockwise rotation of the handle 1 is about 250 degrees, the steering wheel 9, and the flat key gear sleeve 4 to rotate, and then by the mobile rack gear 5 makes axis 11 to the right, the fork 12 shifts 8 hole plate moves to the right, the hole plate 8 from each rack shaft, to prepare for the 8 hole plate translocation; rotating speed of disc 10 to the desired speed position by a pair of bevel gears to 8 hole disc turns corresponding angle; finally, the handle 1 push back to the original position and re positioning, then move to the left and 8 hole disc drive each rack shaft for the corresponding displacement, speed of transformation.When changing speed, in order to make the sliding gear meshing position change in easy meshing, milling machine is provided with a main motor instantaneous impulse device, it uses bump 6 of gear 5 press the micro switch 7 is switched on, with the main motor power, the main motor to achieve a momentary impulse, drive the transmission gear of the main gear box to rotate at a slow speed, sliding gear can be smoothly moved to another position of engagement work.
The above is the introduction of the milling machine speed mechanism.