Review of the universal milling machine 676, description, passport

Kinematic diagram of milling machine 676P

Kinematic diagram of milling machine 676P

Main movement chain

From electric motor 1 with a power of 2.2 kW, the movement is transmitted to shaft 1 using V-belt transmission 2-3. From shaft 1 through the gearbox, rotation is transmitted to the drum gear 20, then to the shaft of the horizontal spindle VI.

The vertical spindle shaft VIII receives rotation from shaft VI through conical 22-23 and cylindrical 24-25 pairs.

Different positions of the gearbox gear blocks (7-6, 5-4, 14-15, 19-18) allow sixteen different speeds to be transmitted to the horizontal and vertical spindles.

Feed chain

All feeds of the machine (table in the vertical and longitudinal directions, spindle headstock in the transverse direction) are carried out mechanically and manually. In addition, fast travel is provided for all directions.

There is no independent feed drive in the machine. The feed mechanisms receive rotation from the main drive (shaft 1 of the gearbox) through the feed box. From the last shaft of the feedbox XIII, with the help of chain gears 50-62, 51-53, rotation is transmitted to the feed mechanisms of the table and spindle head.

Vertical feeds of the table are carried out as follows: shaft XVIII receives rotation from shaft XVII through a conical pair 63-64. To the vertical displacement screw XXIII, forward rotation is transmitted through gears 65-77, and reverse rotation through gears 74-75-76. Since the screw is fixed in the support, the table receives upward or downward movement.

Manual vertical movement is carried out by a flywheel sitting on shaft XXV, through conical pairs 80-81 and 78-79. Longitudinal feeds to the left and right are carried out by switching the clutch on shaft XIX, while rotation is transmitted through gears 66-65 and 74-75-67 to shaft XIX, through a bevel pair 68-69 to shaft XX, and then through gears 70-71 to the shaft screw XXI.

When the clutch on shaft XIV is switched, the headstock cross-feed mechanism imparts forward or reverse rotation to the nut 59 associated with the cross-feed screw, and the spindle head moves forward or backward.

The spindle head is manually moved by a flywheel using a conical pair 55-56 or 56-57.

Accelerated movements are carried out by coupling the coupling on shaft XVII with the coupling of the cylindrical wheel 49. Tables of the main movement and feed mechanisms are given in table. 5 and 6.

Equipment capabilities

The 676P milling machine allows you to mill parts using cylindrical, shaped and disk cutters. This versatile tool can be equipped with two types of spindles:

• rotary-vertical spindle. Allows the use of face and key cutters,
• horizontal spindle. Works with shaped, disc and cylindrical cutters.

The configuration of two types of spindles distinguishes this machine from other devices on the market. This feature allowed the instrument to gain popularity in the seventies and eighties of the last century. Thanks to it, the device is also in demand among modern craftsmen.

An important characteristic is the ability to operate two spindles simultaneously. Using the SF 676 milling machine (a later model, which has minor differences from the previous unit), in addition to milling, you can also carry out the following operations:

• drilling,
• boring,
• countersinking.

The tool allows you to:

• process the external and internal surfaces of parts and rotating bodies using the turning method,
• cut grooves, ledges,
• grind splines on shafts,
• form gears.

The high accuracy of the 676P milling machine (belongs to the “H” category) allows it to be used both in domestic conditions and in small-scale production. Tool shops of machine-building plants are also actively equipped with this tool.

Design Features

The machine is recognized as widely versatile due to the presence of two spindles - horizontal and vertical, as well as a large number of different accessories for the machine. The base of the machine is made of cast iron and ensures the stability of the equipment while absorbing vibrations. The design features allow you to work with both small workpieces and parts up to 80 cm in length. At the same time, the machine is small in size and can be installed in a small workshop.

Spindle speed box

The gear transfer mechanism is located in front of the base of the box. When the handle is positioned as vertically as possible, discs with holes are separated. If the discs need to be brought back to the opposite position, the handle is lowered down.

Gearbox

To maintain the trajectory of the gears, the main gear is used, which is engaged when the gearbox reverse is engaged. In this case, the oil is served in very small portions.

Caliper

The caliper body is a dovetail mechanism. It is responsible for the movement of the main working area in two directions. Vertical advancement is carried out thanks to the guides that are available on the frame. Longitudinal movement is carried out due to horizontal guides. Control occurs due to the running shaft, and the latter receives movement from the gearbox.

Headstock

The spindle head mechanism is equipped with a cleaning rod. Thanks to it, the entire toolkit of the machine is clamped. To set the amount of automatic movement of the spindle head, there are intermediate supports.

Vertical head

The vertical head is mounted into the proboscis faceplate. The design has the ability to rotate 90° from the vertical axis. The operator can set the rotation angle to zero if necessary. In this case, the head must be secured with two pins using internal hexagon bolts. The splines transmit the rotational motion of the spindle tail, and double-row and roller bearings support the vertical spindle.

Corner horizontal table

This structure is cast from cast iron and bolted to the main work surface. For attachment there are T-shaped grooves - 3 pieces.

Vise

They can rotate around their own axis. They are an integral design of the machine and can be additionally mounted on both tables, which greatly facilitates the work.

Slotting head

The slotting head is built into a special round housing. This also includes a special trunk, which is built into the slotting and vertical heads.

Machine 676. Universal milling machine. Manual

This instruction manual for the “Universal Milling Machine 676” contains information necessary both for the operating personnel of this machine and for the employee directly involved in working on this machine. This manual is an electronic version in PDF format of the original paper version. This documentation contains the Passport and Manual (instructions) for the operation of the universal milling machine 676

CONTENT

Purpose Unpacking and transportation Foundation, installation and installation Passport Specification of controls Specification of machine gears, screws and nuts Specification of gears and worm wheels, worms, screws and nuts accessories Main motion mechanics Calculation of spindle speeds Feed mechanics Calculation of feed rates Specification of bearings, rolling components Complete statement Brief description of the machine and accessories

• General layout
• Headstock
• Caliper
• Gearbox
• Gearbox
• Vertical spindle head
• Base and cooling
• Corner table
• Universal table
• Vise

Round table Slotting head Dividing head

• Guitar to dividing head
• High speed head

Electrical equipment of the machine

• Description of the electrical circuit
• Protection

Specification of purchased equipment Specification for the lubrication scheme of the machine Specification of lubrication points and elements of the lubrication system of accessories Instructions for servicing the lubrication system Preparing the machine for start-up Setting up the machine Installing the tool Setting the number of revolutions Setting the feed value Installing accessories Complex division Selection table of replacement gears for cutting spirals Adjusting the machine

• Gearbox
• Gearbox
• Caliper
• Headstock
• Base and cooling
• Vertical spindle head
• Round table
• Dividing head

Machine acceptance certificate Testing the machine for compliance with accuracy standards Accessories and tools for the machine General conclusion on testing the machine Additional comments

download the instruction manual for the wide-universal milling machine 676 in good quality from the link below.

Specifications

Design features affect the main technical characteristics of the equipment:

• horizontal spindle rotation indicators – 50–1630 rpm;
• vertical spindle movement parameters – 63–2040 rpm;
• spindle speeds – 16;
• maximum advancement of the vertical spindle along the axis is 8 cm;
• distance from the axis of the horizontal spindle to the working surface – 8–46 cm;
• from the end of the vertical spindle to the working horizontal surface – 0–38 cm;
• maximum table travel along – 45 cm;
• vertically – 38 cm.

1 dial division is equal to 0.05 mm. The weight of the machine is slightly more than a ton (1050 kg).

Functionality check

This process begins with running the equipment at minimum speed, gradually increasing it to the maximum. The machine must operate in the main working gear of rotation for at least two hours, while the spindle supports cannot be heated above 50 degrees.

After checking the unit at idle speed, it is subjected to load. The milling cutter must operate at maximum cutting force in a short-term 25% overload mode. During normal operation in this mode, no vibration is observed and high processing accuracy is maintained.

Technical characteristics of the milling machine 676P