SU914233A1 - Power head - Google Patents

Description

The invention relates to a machine tool, I structure, intended for deep drilling and can also be used as a thread-cutting head.

A power head is known, which contains a quill with a spindle, a non-self-braking and self-braking screw pair, the nut of the self-braking screw a pair is kinematically connected with the spindle, and the screw with the drive shaft of the joint venture.

The disadvantages of the known devices are the lack of automaticity of the termination of the working supply of the tool and its removal with inadmissible overload, as well as Functional limitations only by drilling.

The purpose of the invention is to improve the reliability of protection of the cutting tool from damage.

This goal is achieved by the fact that the spindle shaft is perpendicular to the drive and driven shafts, has

2

longitudinal keyway on the screw-cutting part, carries two worm wheels, one of which is a nut on the shaft and the other is seated on the spindle shaft through a sliding

5 key, driven and leading shafts of worms of different directions are kinematically connected with the worm wheel themselves, and Between themselves - gears,

driven electromagnetic mufy

tami, and the gear shaft driven on the friction clutch.

The drawing shows the kinematic diagram of the head in two projections.

The device comprises a housing 1, a spindle shaft 2 with a screw thread and a key groove 3, a worm wheel

4, Spiked onto shaft

spindle, worm wheel

U _s

5, which has a screw coupling with the shaft 2. The worm gears 4 and 5 with the toothed rims are kinematically connected with the worms 6 and 7, respectively.

3 91

rigidly planted respectively on

The bollards 8 and 9. The shaft of the electric motor 10, coaxially located relative to the shaft 9, carries a rigidly mounted gear 11 and is connected to the shaft 9 by means of an electromagnetic clutch, 2. (1 gear

1 1 kinematically '(toothed valve) gear 1.3 is mounted on the torque-controlled friction clutch 14., which sits on the shaft 8 and is connected with it by means of the electromagnetic clutch 15.

The head works as follows.

When you turn on the motor 10 and electromagnetic clutches 12 and 1 5 BP? the sky through gears 11 and 13 and a worm η · "Κ) a pair of 6-4 is connected to the shaft 2 of the spindle, and through the shaft 9 and the worm 7 to the worm wheel 5.

The feed speed depends on the pitch Ή of the screw cutting of the spindle shaft 2 and the gear ratio ί in the kinematic chain from the worm wheel 4 to the worm wheel 5, ΐ must be less than one, i.e. the speed of rotation of the worm wheel 5 is less than the speed of rotation of the wheel 4. The feed rate per revolution is determined by the formula

5 ₀ = (1 - 1)

where Ϊ = ’7th>,

where C ₆ - gear ratio

in the worm pair 4-6;

Πα, .- ήή ~ gear ratio in a pair of gears 13-11; ΐ _{7 A.} - gear ratio

in the worm pair 7-5.

Fast movements of the spindle (tool) are carried out as follows.

Electromagnetic clutch 12 is turned off, and clutch 14 is turned on. Wheel 5 is at rest. In this position, the accelerated feed (approach) of the tool is determined by the formula

^{5 n} '' 1 $ - ΛΥ 'B ~ &,:''

where η is the speed PA motor shaft, rpm;

- before the full-time relationship of a pair of gears 13- 1 1;

33 4

1 c, ₆ - gear ratio

in the worm pair 4-6;

14 - screw thread pitch

spindle shaft.

Electromagnetic coupling 12 is on, and clutch 14 is turned off. Wheel 4 is at rest. In this case, the accelerated retraction of the tool 5 ^{M /} , which is determined by the Formula

2 "= η · 1 ₅ „ _a - K

I

where η is the speed on the electric shaft

engine rpm;

6 - spindle thread pitch;

ϊ ₅ .. _& . - gear ratio

in a worm pair 5-8.

When the cutting forces exceed the set torque of the friction clutch 14, the gear wheel 13 slips on the clutch 14. As a result, the difference in the speeds of rotation of the worm wheel 4 relative to the worm wheel 5 and the feed decreases.

When biting a tool, practically the same thing happens as an accelerated retraction of the tool. After the tool is released, the cutting process (working feed) is automatically resumed.

The work of the head as a thread-cutting is due to the fact that the blueberry pair 5-7 is not self-braking. The friction clutch 14 is configured to the size of the tool. The penetration of the tap into the hole is made with an accelerated feed: the electromagnetic clutch 12 is turned off, the clutch 14 is turned on. As a result, the spindle shaft 2 is forming tension in the pair - wheel 5, the latter rotates but according to the law set by the tool, without interfering with the feed according to the tool step.

Claims (1)

Claim The power g’olov containing paralelly leading and driven nala, kinematically interconnected by means of gears c. electromagnetic clutches, spindle, carrying gear, forming with. He screw pair and kinematically connected with the drive shaft, about tl and h and y sch and I am. I five the fact that, in order to increase the reliability of the cutting tool protection from damage, the spindle shaft is perpendicular to the driving and driven shafts and is equipped with a second toothed gear set on the sliding 914233 6 key, kinematically connected with the driven shaft.