US1505131A - Automatic turret lathe - Google Patents

Description

Aug. 19, 1924.- 1,505,131

' T. E. BUSCHMANN AUTOMATI C TURRET LATHE Filed March 11, 1921 2 Sheets-Shet 1 Aug 19 1924, I 1,505,131

' T. E. BUSCHMANN AUTOMATIC TURRET LATHE Filed March 11, 1921 2 Sheets-Sheet 2 Patented Aug. 19, 1924.

UNITED STATES THEODOR EUGEN BUSCI-IMANN, OF GHEMNITZ-KAPPEL, GERMANY.

AUTOMATIC TURRE'I LATHE.

Application filed March 11, 1921.

T all whom it may concern Be it known that I, Tnnonon EUGEN BUSCI-IMANN, a citizen of the German Republic, residing at Chemnitz-Kappel, Germany, have invented certain new and useful Improvements in Automatic Turret Lathes (for which I have filed applications in Germany Nov. 3, 1919, and Oct. 9, 1916), of which the following is a specification.

My invention relates to a screw-cutting device for automatic tool turrets, and more particularly has for its object to provide the possibility of employing in connection with automatic turret lathes fitted with a tool turret for the purpose of changing tools, a

screw-cutting device in the case of which the die spindle is adapted to produce the thread by being operated at a suitably increased number of revolutions relativelyv to the spindle.

In order to enable the rotary motions of the tool turret to be carried out Without impediment, the driving motion is furnished by a shaft arranged in the centre of rotation of the revolving tool box, as has been done with automatic tool turrets. In accordance with my invention, the said driving shaft is adapted to support the coupling elements serving to drive the die spindle, so that this latter with its accessory parts may be conveniently housed within the space available. Furthermore, the connection between the driving shaft and the die spindle is established on such lines that the latter will be automatically engaged in the course of the movemen executed by the tool turret which causes the die to be brought up to the work piece, and that it will be as suddenly disengaged, after the thread has been completed, as a result of its displacement by the die. To this end, there is arranged on the die spindle a cam which, when the thread has been cut, will, by reversing a lever, release a disengaging pin which will then jump for ward into the coupling, pull this latter apart and keep it in this position until the die has completely run oft from the thread.

In the drawings affixed to this specification and forming part thereof, two tool turrets (of the Browne and Sharpe type in Figs. 1 to 5 and of the Cleveland type in Figs. 6 to 8) and embodying my invention are illustrated by way of example. In the drawings Fig. 1 is a section, of the tool turret pro- Serial No. 451,649.

vided with the improved screw-cutting device.

Fig. 2 is an end view thereof,

Fig. 3 is a detail view illustrating the manner of disengaging the die spindle,

Figs. 4 and 5 are detail views disclosing the disengaging lever in the position when thrown in and when thrown out, respectively.

Fig. 6 is a cross section of a tool turret of a Cleveland lathe.

Fig. 7 is a side elevation of Fig. 6, and

Fig. 8 is a detail view on an enlarged scale.

Referring to Figs. 1 to 5 of the drawings, the tool turret 1 is rotated when changing tools by means of an indexing gear wheel 2 mounted on the hollow shaft 3 of the tool turret. I shall not here enter into a more detailed description of the feed mechanism and the further construction of the tool turret mechanism, since it is assumed that these elements are generally known to all familiar with the art. Attention is only directed to the fact that in the type of construction here shown, the tool turret is mounted on a carriage affording the possibility of moving the tools up to the workpiece. The screwcu'tting device is inserted in a hole lformed in the tool turret which serves to accommodate the tools. At the free end of the shaft of the tool turret there is loosely mounted a belt pulley 5, which is kept running continuously and serves as a driving means for the die spindle l5. Rigidly connected to the said pulley is a clutch ring 6. Within the interior of the shaft of the tool turret there is lodged a driving shaft 7 carrying at its free end a clutch member 8. At the opposite end of this shaft there is mounted a bevel wheel 9 and a disengaging cam-faced clutch member 10. The driving shaft 7 is shiftable endwise and is acted upon by a spring 11 in such a manner as to cause the coupling members 6, 8 to constantly strive to enter into engagement. lVithin the hole formed in the tool turret there is inserted a bushing 12, the bore of which is adapted to accommodate a driving sleeve 13 operated by a bevel. wheel 14:. The driving sleeve 13 serves to transmit the rotatory motion to the die spindle 15 which is constantly drawn by a spring 16 toward the interior of the tool turret. On the die spindle there is mounted the disengaging cam 17, while parallel to this said shaft there are located the disengaging pin 18 engageable with the clutch member 10 and a spring 19. On this disengaging pin there is arranged a sleeve 20 having two arms 21 and 22 and provided at its hub with inclined faces adapted to cooperate with similar inclined faces 23 appertaining to a stationary sleeve 24:. For the purpose of bringing the screw cutting device into engagement, there is provided a stationary pin 26 at the carriage of the tool turret.

In Fig. 1 the drive mechanism for the die is shown in the position it assumes immediately upon conclusion of the screw cutting operation. In this position, the tool turret is fed forward in the indexing operation from tool to tool. During the lastpart of the indexing movement of the said tool turret for the purpose of bringing the die into its operative position, the arm 21 of the lever moves past the stationary pin 26 (Fig. and in so doing is turned sideways. As a result, the inclined faces 23 of the sleeve 20 move up the stationary sleeve 2st and draw the disengaging pin outward counter to the action of spring 19, so that now the throw out clutch 10 will be released. Spring 11 at the same time displaces the driving shaft 7 and thus brings coupling elements 6 and 8 into engagement, whereby the die. spindle axis will receive motion from bevel wheels 9 and 1a. Fig. 3 illustrates the disengaging pin in its operative position. The die is moved up to the workpiece by the tool turret for the purpose of initiating the cutting operation. In accordance with the die proceeding with the cutting operation, the die spindle gradually comes to be displaced endwise until the cam 17, mounted on said spindle, reaches arm 22 of lever and reverses this latter, sothat now the inclined faces 23 will slide down into sleeve 2a. Thus, the disengaging pin 18 is brought within reach of the external curved cam face arranged on the throw out clutch l0, displaces the driving shaft 7, pushes the clutch elements 6 and 8 apart again and locks them in thisposition, so that the die may now run off from the finished thread.

It is obvious that the driving motion may also be transmitted by other clutch means. I may also provide other means within the meaning of the claims for causing the operation of the preferable cam-faced clutch member at the termination of the indexing movement.

In the construction illustrated in Figs. (3 to 8, the workpiece 2G is driven by the main drive head stock and is successively tooled by the different tools. a part of which are honsed in the tool turret.

denotes the. casing surrounding the tool turholes I of the tool turret.

ret and within which this latter is adapted to turn when changing tools. The tool turret is mounted on a hollow shaft 28. lVithin the shaft 28 there is located the driving shaft 30 provided at its rearward end (not shown) with a driving wheel serving to continuously keep shaft 30 in motion. ()n this last-named shaft is fixed a clutch 31 cooperating with a displaccable clutch 32. Clutch 32 is provided with a transverse slot 33 with which the pins 34 of sleeve 35 are adapted to enter into engagen'lent and whereby this said sleeve is connected in such a manner with clutch 32 as to enable this latter to be displaced. ithin sleeve 35 there is arranged a spring 36, which, when the clutch is released, causes both clutch elements to be thrown into engagen'ient. On the periphery of the clutch element 32 there are formed inclined faces 37 adapted to effect engagement and disengagement, while on the sleeve 35 there is keyed a transmission wheel 38 secured in its position by a nut 39. The sleeve 35 is housed in the bushing 40 arranged in the centre of the tool turret.

The screw-die is inserted in one of the The bushim 41 is spring-actinglv secured in the tool hole 4. Within the said bushing there is located the driving sleeve 42 on one end of which there is keyed the driving wheel 42% being further secured in its position by a nut 44-. 45 is the die spindle the forward extremity of which is shaped to form a head for the reception of the screw-die 46. Spindle 4F is axially movable and secured to the sleeve 25 by a key 47. On the said spindle there is moreover arranged a cam 18 serving to cll'ecl its disconnection from the driving elements. On the rear end of the spindle there is disposed a spring 49, secured by an adjusting collar .30 and serving to retract the spindle whenever re quired. This said spring bears up with its one end against an intermediate collar 51 secured within the tool hole by a screw 52. The means employed to connect and (liSCOllnect the driving mechanism consist of a simple bolt 53. This bolt is provided with teeth with which the teeth of the ratchet wheel 54 are adapted to gear and the shaft 55 of which is mounted in the sleeve 56. ()n the said shaft 55 there is fixed a lever 57 serving to establish the connection with the driving mechanism. Vith the ratchet wheel 54 there is coupled a disc 58 provided at its front end with two continuous V-shaped. slots 59 which a. bolt (30 possessing a conical or triangular projection 61 is :nlaptt-ul to engage. For the purpose of enabling the bolt til) to accommodate a pressure spring (i2, the sai-il bolt is made hollow. By this means the ratchet wheel 5+ may be locked in its end position. lfiv means of a key (323 the spring actuated bolt is secured against rotation.

At the bearing 27 of the tool turret there is provided a stationary pin 64 serving to rock the lever 57 outward when establishing the connection with the driving mechanism.

The manner of operation of the device is as follows:

As the tool turret l executes the last partial indexing movement, in order to bring the die into its operative position, the lever 57 moves past the stationary pin 64. Lever 57 was originally located in the position indicated by dash lines, but is now shifted by pin 64 into the position shown in full lines. At the same time, ratchet wheel 54 withdraws bolt 53 for such a distance that clutch 32 will be released and brought into engagement by spring 36 wit-h the permanently rotating clutch element 31; The die spindle 45 is driven by sleeve and the transmission Wheels 38 and 43. The cutting operation on the part of the die is initiated by the endwise displacement of the tool turret. The cutting operation having set in, the die spindle is gradually shifted by the cutting-tool until the cam 48 attains bolt and in so doing effects its displacement. Bolt 53 is thus shifted toward the clutch member 32 which in the course of the rotatory motion rolls with its inclined face 37 on said bolt 53 and is by these means disengaged from the teeth of the permanently rotating clutch element 31, so that now the die spindle 45 will be brought to a stop and the die itself will run clean off from the finished thread by the action of the spring 44. The V-shaped slots 59 formed in the disc 58 arranged at the ratchet wheel 54 serve to lock the coupling operating bolt or rack bar 53 in its extreme positions.

It may be noted in conclusion that the continuously rotating shaft may also be used for driving drilling devices such as are required for drilling small holes. A device of this kind is likewise illustrated in the drawings in dotted lines.

I claim z 1. The combination with an intermittently rotatable tool carrier, of axially movable rotatable tools on said carrier, tool driving means on the carrier, a cam-faced coupling member in operative connection with said driving means and said tool, spring-actuated coupling operating means on the carrier, means on said tools engageable with said coupling operating means, and relatively stationary operating tappets in the circular path of movement of the coup-ling operating means.

2. The combination with an intermittently rotatable tool carrier, of axially movable spring actuated rotatable tools, a driving shaft in said revolving tool carrier, camfaced coupling means opei'albly connecting said driving shaft to said tool, coupling controlling means on said carrier and engageable with said coupling, relatively stationary means outside of said carrier in the circular path of movement of said controlling means, and means on said tools engageable with said controlling means and operating tappets on said carrier.

3. The combination with an intermittently rotatable carrier, of an axially movable, rotatable spring-actuated screw cutting tool, a driving shaft, located in said carrier, a cam-faced coupling member cooperating with said shaft and said tool, spring influenced controlling means on said carrier engageable with said coupling, means on said tool engageable with said controlling means, and operating tappets outside of said carrier engageable with said controlling means.

4. The combination with an intermittently rotatable carrier, of an axially movable, rotatable spring-actuated screw cutting tool, a driving shaft extending into the rotary centre of said carrier, a cam-faced coupling member operatively engageable with said shaft and said tool, coupling controlling means on said carrier and engageable with said coupling, means on said tool engagea'ble with said coupling, a relatively stationary member outside of said carrier in the rotatable path of said controlling means, and operating tappets on said carrier.

5. The combination with an intermittently rotatable tool carrier, of an axially movable rotatable spring-influenced screw cutting tool. housed in said carrier, a driving shaft extending into the rotary centre of said carrier, a cam-faced coupling member cooperating with said shaft and said tool, a displaceable rack bar engageable with said coupling, operating means for said rack bar, means on said tool engageable with said rack bar, and relatively stationary operating tappets outside of said carrier in the circular path of movement of said. rack bar operating means.

In testimony whereof I aflix my signature.

THEODOR EUGEN BUSCHMANN.

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