Internal Grinding Machine

Overview

A cylindrical, conical or other shaped wire surface of a workpiece that is machined to form an inner bore surface and a grinder thereof.

The internal grinding machine is divided into a common internal grinding machine, a planetary internal grinding machine, a centerless internal grinding machine, a coordinate grinding machine and a special purpose internal grinding machine.

According to the grinding wheel shaft configuration, the internal grinding machine has horizontal and vertical points.

① Common

The workpiece is held by a chuck mounted on the main shaft of the head frame for a circular feed motion.

The worktable drives the grinding wheel frame to reciprocate longitudinally along the guide rail of the bed.

The head frame moves along the sliding saddle for lateral feeding.

The headstock can also be rotated around a vertical axis to an angle to grind the taper.

② Planets

During work, the workpiece is fixed, and the grinding wheel rotates around the axis of the machined hole in addition to the high-speed rotation of its own axis to achieve circumferential feed.

It is suitable for grinding large workpieces or workpieces that are not suitable for rotation, such as cylinder blocks for internal combustion engines.

③ Centerless

The outer circumference of the workpiece is supported on the roller or the support block during operation.

The end face of the workpiece is attracted by the magnetic chuck and is rotated, but slightly floated to ensure the concentricity of the inner and outer circles.

The grinding wheel speed of the small-sized internal grinding machine can reach up to hundreds of thousands of revolutions per minute.

Internal grinding machines used in high-volume production require a high degree of automation.

The size can be automatically controlled with a plug gauge or micrometer during the grinding process.

Structure

The internal grinding machine is divided into a common internal grinding machine and a universal internal grinding machine.

Among them, the universal internal grinding machine is the most widely used grinding machine.

The inner cylindrical surface, the inner conical surface and the stepped shaft end surface of various shaft and sleeve type workpieces can be ground on the inner cylindrical grinding machine.

The main part of the grinding machine is the bed.

The bed is the basic support of the grinding machine, and is equipped with a grinding wheel frame, a work table, a head frame, a tailstock and a lateral sliding saddle.

Keep these parts in exact relative position while working.

The inside of the bed is used as an oil pool for hydraulic oil.

The head frame is used to mount and hold the workpiece and drive the workpiece to rotate. The headstock can be rotated 90° counterclockwise in the horizontal plane.

The inner grinding tool is used to support the grinding wheel spindle of the grinding inner hole.

The inner grinding tool spindle is driven by a separate motor.

The wheel carrier is used to support and drive the grinding wheel spindle at high speed.

The wheel frame is mounted on the sliding saddle. When the short conical surface needs to be ground, the wheel frame can be adjusted to a certain angular position within the horizontal plane by ±30°.

The tailstock and the top of the headstock together support the workpiece.

The sliding saddle and the infeed mechanism rotate the lateral feed handwheel.

The infeed mechanism can be driven to drive the saddle and the wheel frame thereon for lateral feed motion.

The workbench consists of two layers.

The upper table can be rotated by an angle (±10°) around the horizontal plane of the table to grind a long conical surface with a small taper. The head frame and the tailstock are mounted on the upper workbench.

They can be reciprocated longitudinally along the bed rails along with the workbench.

The application of machine tools: general precision class universal internal grinding machine, the machine accuracy is IT6, IT7.

The surface roughness value Ra of the machined surface can be controlled in the range of 1.25 and 0.08 μm.

The universal internal grinding machine can be used for finishing the inner and inner cylindrical surfaces.

Although the productivity is low, the universal internal grinding machine is widely used in single-piece small batch production workshops, tool workshops and machine repair workshops because of its versatility.

Characteristics

★ The feed and compensation of the machine tool are carried out by two transmission mechanisms that do not interfere with each other.

The feed system has a fixed-point grinding function, which is either manual or hydraulic.

★ The machine tool has a fast-jumping mechanism, so it is not necessary to re-tool the knife after exiting the grinding wheel for measurement or trimming.

★ The workbench retreats with a medium stop device. The rewind distance can be adjusted as needed to reduce the assist time.

★ The workbench starting handle is equipped with a safety interlock to ensure the safety during loading and unloading and measuring work.

★ The maximum speed of the machine wheel is 24000 rpm to improve the grinding hole.

★ User special order. The electric spindle can be modified by variable frequency speed to grind the small diameter inner hole.

★ This machine is equipped with an end grinding device to ensure the verticality of the hole and end face of the workpiece.