Attachments for the tailstock of a lathe. Centers for lathes. Types of turning centers

31.07.2018

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The tailstock quill is moved by a hydraulic cylinder controlled by a handle located on the hydraulic tank. Inside the body of the headstock there are two hydraulic cylinders that serve to secure the quill; when the center of the tailstock rests against the product, oil enters these cylinders and they clamp the quill.

Mounting on two ends

Tails are used on lathes and other machine tools to support one end of a workpiece in contact with a live or dead center. The tailstock is a cast iron assembly that can slide lengthwise and be locked in place and is used for long term work on site or to install a drill chuck for drilling at the end of a job. There are two types of tailstock: manual and pneumatic. Manual tailstocks require workers to apply pressure. Pneumatic tailstocks are driven by machines.

The tailstock quill moves from a hydraulic cylinder attached to the headstock body. The quill is fixed automatically after the center of the tailstock enters the center socket of the part. It is carried out with the help of two hydraulic cylinders, pulling together two pairs of crackers, pressing the pintle to the headstock body. The tailstock spindle rotates in rolling bearings which are lubricated with grease. The knockout of the center is carried out with the help of a special wedge through the oblong holes in the body of the headstock and the quill.

If tail stock is used, a dead center may be used to support the workpiece, alternatively a live center may also be used. Lathes with a cylindrical tailstock that can rotate about a vertical axis are lathes.

All lathes have support centers, which are a horizontal beam. All tailstocks are a harsh chest. # Bench centers are precision ground tapered cylinders with a 60° pointed tip and morse taper shaft. The tail wheel flywheel is a wheel with a handle and is used to move the tail rod in and out of the tail casting. The spring tail is a piston shaft that can be moved in and out of the tail section by turning the tail rod flywheel.

The tailstock quill is moved by a hydraulic cylinder.

The tailstock quill is retracted. At the end of the stroke of the piston 17, air through the hole in the pneumatic cylinder 16 will enter the cylinder 19, which feeds the blanks to the line of centers. At the same time, air is supplied to the valve 14 to turn off the self-propelled gun.

The quill of the tailstock is connected by a system of rods to the gate of the bunker, which ensures the opening of the bunker at the beginning of each cycle.

It has a tapered inner bore to accept a taper shank. The lathe may or may not have a stand that sits on the floor and raises the center of the bench to working height. Some lathes are small and sit right on a workbench or table and don't have a stand. The stand center is an important component lathe and is available in various sizes to suit product requirements. Auxiliary inspection equipment is required to test the workpiece performance for various machines.

Types of turning centers

Tailstock alignment involves placing a small center of the drill into the tailstock, turning the stem between centers and measuring the shank diameter, and setting a straight shank between centers. Bench centers are usually used for long pieces.

The tailstock quill is lubricated through oilers 13 and 14 with Turbine-22 oil. The quill is lubricated at least once per shift. The roller guide keys of the lead screw are packed with TsIATIM-203 grease at the factory and do not need lubrication during operation. Lubrication of the gears of the feed mechanism is carried out by leaks from the hydraulic motor.

Table tops and bench centers are used in many lathe applications. Drilling, reaming, centering and countersinking are done on a lathe using tailstocks and support centers. Countertops and desktop centers must comply with various standards specified by the International Organization for Standardization.

Rotating center drawing exercises

The tailstock as a counter when turning the components takes a pen with a fixed or rotating centering. In the next article, we will take a detailed look at the design of a rotating centering point. Lathe: The tailstock serves as a counter when turning components. It raises the centering which is rotated by the moving component in rotation. Babman is also used as a tool holder.

The quill of the tailstock, which has an adjusting movement depending on the length of the tap being processed, has movement only along the axis.

The tailstock quill is pressed by a spring, the force of which depends on the distance rear center from the workpiece. The position of the rear center is adjusted by moving the headstock along the bed rails.

Purpose of the exercise: We need to create a general drawing of a rotating grain tip. The following text provides design information. The rotating tip is installed in the housing. The sketch above shows the components used. The clamp nut clamps the front two rolling bearings, the needle bearing absorbs any thermal expansion of the moving tip. The nut is secured with a threaded stud.

For bearing parts, circlip and grub screw on the table book or you search online. Center point The following dimensional drawing shows the important dimensions for the individual parts used. Draw the cap and nut at a distance of your choice.

The tailstock quill is pre-pulled out by 80 - 100 mm and secured.

For ease of maintenance of the machine, it is advisable to move the tailstock quill by means of a handwheel located on the front side of the machine.

The tailstock quill has the largest longitudinal movement of 40 mm, and the headstock spindle - 5 mm. In the collet, the quills strengthen the cutting tool, and in the collet of the headstock, the workpiece. Handwheel 2 serves to clamp the collet with a cutting tool and feed the quill. Handwheel 3 serves to clamp the collet with the workpiece. When the cutting tool presses on the workpiece, the headstock spindle moves to the left side, and the left pulley 4, on which a straight belt is put on, turns on the spindle rotation to the right side at a speed of 820 rpm. After threading, the translational movement of the cutting tool is delayed. The headstock spindle moves to the right side, and the right pulley 5, on which the cross belt is put on, tells the spindle to rotate left at a speed of 1300 rpm. The tap is unscrewed from the workpiece.

The tailstock quill stroke is 150 mm, which allows you to install short and long parts without changing the tailstock.

Retraction of the tailstock quill is carried out only when the grinding headstock is retracted.

Instructions for work

"Disassembly and assembly of the tailstock of a lathe."

I. Rules for safe work.

You can only use a serviceable tool of the appropriate size. The use of gaskets if the key is larger than required, as well as building up the handle of the keys with tubes or other objects, is prohibited, as this may lead to slipping of the tool.

intelligence and injury.

It is not allowed to start work without familiarizing yourself with the tailstock device according to the drawing.

Before starting work, you should prepare a place to place the parts. Small parts are put in a box. The tailstock quill must be carefully protected from dirt and dust.

A hammer can only be used with the permission of the teacher. In no case is it allowed to use a chisel to unscrew bolts and nuts.

For the correct assembly of the tailstock, it is necessary to understand its structure and the interaction of individual parts, and also to know the disassembly sequence well in order to be able to assemble in the reverse order.

Fig.1. Tailstock lathe: 1, 14 16, 18, 24 - screw; 2, 7, 19, 21 - nut; 3 - quill; 4 - body; 5 - handle; b - power screw; 7 - nut; 8-head; 9 - limb bushing; 10-spring; 11 - flywheel; 12 washer; 13 - key; 15 - handle; 17 - plate; 20 - key; 22 - diameter; 23 - bolt.

Tools spanners 12, 10 and 8 mm, 5 mm screwdriver.

Sequence of work.

1. Familiarize yourself with the tailstock device according to the drawing.

2. Unscrew the nut 21 from the bolt 23 and, lowering the diameter 22 together with the bolt 23 down, take them out and put them on the workbench.

3. Remove the headstock together with the bottom plate 17 and transfer it to the workbench.

4. Rotate the flywheel 11 until the quill 3 with the nut 7 come off the power screw 6, then remove the quill.

5. Unscrew screw 14, remove washer 12 and flywheel 11 with limb bushing 9, spring 10 and handle 15.

6. Remove the limb sleeve 9 from the flywheel 11 and remove the spring 10 from it.

7. Remove key 13.

8. Unscrew the screw 16 and remove the head 8, as well as the power screw 6.

9. Unscrew screw 1 and unscrew nut 2 from it.

10. Pull out handle 5 with croutons and remove croutons.

11. Unscrew the screw 18 for the transverse movement of the body 4 of the tailstock.

12. Unscrew the screw 24 that connects the headstock body to the plate 17.

13. Disconnect the body from the plate 17, remove the nut 19 and the key 20.

14. Wipe all parts with a rag.

15. Lubricate surfaces between which friction occurs with a thin layer of grease.

16. Collect the headstock and install it in place.

III. Tasks.

1. Determine the tailstock screw pitch.

2. Determine the largest possible displacement of the tailstock body relative to the plate.

IV. Questions to review.

1. How to prevent self-unscrewing of the quill?

2. What is the purpose of the spring, which is installed in the limb sleeve?

3. What is the purpose of the nut on the screw?

Instructions for work.

"Setting up the machine and processing the outer cylindrical surface".

I. Rules for safe work.

Before starting work:

1) fasten all buttons so that there are no hanging parts of clothing that can be caught by the rotating parts of the machine; remove hair under a headdress;

2) familiarize yourself with the placement of buttons and control knobs and the purpose of each of them;

3) check that all controls are off or in the neutral position.

During work it is forbidden:

1) lean on the machine;

2) switch the belt drive on the go;

3) switch gear box and feed box on the go;

4) leave the machine without supervision;

5) stop the chuck by hand after turning off the machine;

6) measure the part on the go.

Violation of these rules may result in an accident

Remember that the "Stop" button is colored red.

1. Install the chuck in the spindle, for which do the following: wipe the thread at the end of the spindle and in the chuck hole with a rag and lubricate it with oil; screw on the cartridge; protect the cartridge from self-unscrewing.

2. Install the turning tool by doing the following: wipe the center and hole in the tailstock quill with a rag, install the center in tailstock; bring the tailstock to the caliper; using a set of pads, install the through cutter so that its top coincides with the top of the center (there should be no more than two pads, they should not be shorter than the part of the cutter that is fixed in the tool holder, the cutter overhang should not exceed 1.5 heights); fasten the cutter.

3. Check that the dimensions of the workpiece correspond to the dimensions specified in the drawing.

4. Fix the workpiece.

5. Set up the machine for the specified mode of operation.

Turn on the machine.

7. Bring the cutter in contact with the workpiece.

8. Move the cutter with the support to the right.

9. Set the cutter to the specified cutting depth; combine the zero division of the limb with the risk on the fixed screw hub; determine the value of the division of the dial, turn the cross feed screw in accordance with the specified depth of cut.

10. Machine a belt 5.7 mm long.

11. Stop the machine.

12. Check the dimensions of the workpiece with a caliper.

13. Roughly grind the workpiece using manual feed.

14. Set the cutter to the specified depth of cut for fine turning.

15. Turn the workpiece clean using the power feed.

16. Stop the machine.

17. Check the size of the workpiece with a caliper.

18. Remove the part and cutter.

19. Clean up the workplace.

III. Questions to review.

1. Why is the cutting length limited?

2. Why is it not allowed to fix the cutter with one bolt?

3. How to eliminate the possibility of self-unscrewing of the chuck?

The results of experimental verification of the optimal model of teaching students in grades VII-VIII in the process of working on screw-cutting lathe

The experimental base for qualification work to test the designed model of the process of teaching students in grades VII-VIII to work on a screw-cutting lathe is secondary school No. 5 in Oktyabrsky, Krasnoarmeisky district, Krasnodar Territory.

The pedagogical experiment was attended by Ph.D., Professor Shchekoldin A.G., Ph.D., Professor Zarechnaya L.P., Ph.D., Associate Professor Zinoviev A.I., Ph.D. n., Associate Professor Radchenko N.V., Ph.D. Ph.D., Associate Professor Makhnenko A.Ya., Candidate of Pediatric Sciences, Associate Professor Zarechny A.V., Senior Lecturer Ilyinykh A.P., Director of Secondary School No. 5 - Nelly Pavlovna Maksimenko, Deputy Directors for Educational and Educational Work, teacher technologies - Mishchenko Andrey Eduardovich, student of the Faculty of Technology and Entrepreneurship Lukyanchenko D.A., students of VIII "A" class - 12 boys. A total of 29 people took part in the experiment.

Experimental work was carried out in the process of passing pedagogical practices. The experimental work consisted of ascertaining and forming experiments.