US1736421A - Steady rest for automatic lathes - Google Patents

Description

Nov. 19, 1929. D. TURcoTT STEADY RST FOR AUTOMATIC VLATHES Filed June 23. 1928 3 Sheets-Sheet l 'Il/Ummm, Q

I l @antifa/'C022 vr-Emmi l.

Nov. 19, 1,929.

' D. TURcoTT 1,736,421

STEADY REST FOR AUTOMATIC'LATHES Filed June 23, 1928 3 Sheets-Sheet 2 HHIIHIIHIIIHHHIIIHIIHIIIIIHHWHU Nov- 19,y 1929. D. TURCOTT 1,736,421

` STEADY REST FOR AUTOMATIC LATHES Filed June-25, 1928 3 Sheets-Sheet 5 Patented Nov. 19, 1929 UNITED STATI-I PATENT oFFclcE DAVID TURCOTT, 0F BELOIT, WISCONSIN', ASSIGNOR TO YATES-AMERICAN MACHINE ,y

COMPANY, OF BELOIT, WISCONSIN, A CORPORATION OF DELAWARE STEADY REST FOR AUTOMATIC LATI-IES Application filed June 23,

This invention has to do with automatic wood-turning lathes of the type in which the stock is brought into engagement with rotating knives and is rotated on its own axis while in such engagement.

The purpose of the invention is to provide a novel steady rest for supporting the stock near the point of cut during the cutting operation.

The device of the invention will yield at one stage in the cutting operation to compensate for irregularities in the shape of the rotating stock, but will become non-yielding at a subsequent stage to support the stock firmly against the action of the knives.

While the foregoing statements are indicative in a general way of the nature of the invention, other objects and advantages will be evident to those skilled in the art upon a full understanding of the construction, arrangement and operation of the device.

One form of the invention is presented herein for the purpose of exempliication, but it will of course be appreciated that the invention is susceptible of embodiment in other structurally modified forms coming equally within the comprehensive scope of the claims.

In the accompanying drawings:

Fig. 1 is an end view of an automatic lathe equipped with the steady rest of the invention, showing the carriage ofthe lathe in a partially advanced position prior to the cutting operation; v j

Fig. 2 is a plan view of the steady rest;

Fig. 3 is a diagram of the electric circuit used in connection with the steady rest;

Fig. 4 is a fragmentary end view of the lathe, showing the carriage in its fully advanced position near the completion of the cutting operation; and

Fig. is a similar View, showing the carriage in its fully retracted position upon com,- pletion of the cutting operation.

The particular lathe illustrated in the drawings is of well known construction and therefore will not be described in detail. Briefly, it includes a main frame 10, a set of rotating knives 11 supported by the frame, a carriage 12 pivoted at 13 to the frame, a pair of rotating chucks 14 supported'by the carriage, and

1928. Serial No. 287,853.

a feed lever 15 connected with the carriage for swinging the same toward the frame a distance limited by an adjustable stop 16, whereby to cause a rotating piece of stock 17 held between the chucks to be advanced into engagement with the knives and turned down to the size indicated at`18. 4 I j The steady rest with which the lathe is equipped includes a bracket 19 supported by the carriage 12, a shaft 2O journaledin the bracket, a stock-engaging arm 21 journaled on the shaft, a cam-engaging arm 22 secured to the shaft alongside the arm 21, an adjustable connection 23 between thev arms 2.1 and 22, amagnet-engaging arm 24 secured to the shaft within a housing 25 formed in the bracket, an electrically energized magnet 26 positioned in the housing beneath the arm 24 and a coil spring 27 positioned in the housing above the arm 24. i

The arm 21 of the steady rest extends beneath the stock 17 and is provided with a plate 28 which is adapted to bear against the stock under the pressure exerted by the spring 27 through lthe arm 24, the shaft 20, the arm 22, and theadjustableconnection 23.

The arm 22 extends in a direction opposite the arm 21 and is provided with a cam roller 2 9 which is adapted to engage with and ride upon a cam 30 on a portion 31 of the frame 10 when the carriage 12 is fully retracted, as shown in Fig. 5, whereby to cause the plate 28 to move away from the stock far enough to permit the finished stock to .be replaced by other stock. v

The adjustable connection 23 between the arms 21 and 22 is present in order to permit the arm 21 to be set at various angles with respect to the arm 24, thereby rendering it unnecessary to alter the position of the magnet 26 when a change is to'be made in the diameter of the cut on the stock. The connection 23 consists of a bolt 32 which projects laterally from the arm 22 through'an arcuate slot 33 in the arm 21, and a nut 34 on the bolt which may be tightened against the edges of the slot at any point throughout the length of the saine. The steady rest is set for any particular diameter of cut by first releasing the connection 23, then moving the plate 28 int@ a. position tangential to the circle of the iinished cut on the stock, then moving the arm 2a into a position in contact with the magnet 26. and then tightening the connection 23.

The spring 27 permits the plate 28 to yield downwardly during the first part of the cutting operation to compensate for the initial irregularities in the shape of the rough stock. After the stock has turned about 90 on its own aXis While in its fully advanced position and has been cut throughout that angle, the plate 28 will follow the cut surface of the stock upwardly into a position tangential to t-he finished circle of cut, as shown in Fig. 4, and the magnet 26 will become energized and act on the arm 24; to render the plate nonyielding during the remainder of the cutting operation.

When the plate 28 reaches the finished circle of cut on the stock, the magnet 26 is auto- -mat'ical-lyenergized by an electric coil 35 on one leg of the magnet. The circuit for the coil, which is shown diametrically in Fig. 3, le'ads from one end of the coil to a contact point which constitutes the previously mentioned adjustable stop 16 for the carriage, and 'such contact point is adapted to engage with Va stationary contact point 36 on the frame when the carriage reaches its fully advanced pnsition. The 'circuit leads from the other end of the coil to a contact point 37 within the housing 25, and such contact point is adapted to be engaged by a movable Contact peint 38 ony the end ofthe arm 24. T he two contact points 36 and 38 are in turn connected with the opposite leads of a closed electric circuit.

From the foregoing, it will be understood that the magnet 26 will not be energized to render the plate 28 non-yielding until after the carriage 12 has reached its fully advanced position and the cutting operation has progressed to a point where the plate 28 has moved upwardly and is bearing against the finished circle of cut on the stock, since the circuit fory the coil 3'5 will not be completely closed until the Contact point 16 has come into engagement with the contact point 36 and the Contact point 37 has been engaged by the contact point 38.

Upon completion of the cutting operation, the carriage is retraced by manipulation of the feed lever, and. as soon as the Contact 13 on the carriage withdraws from the contraeL point 36 on the frame, the magnet 25 will become cle-energized, with the result that, when the carriage reaches its fully retracted position, the steady rest is in an unlocked condition and the cam 29 can operate to swing the plate 28 downwardly away from the stock to permit the stock to be changed.

The steady rest possesses many distinctive advantages. wWhile it will yield readily to the irregularities of the stock during the first par-t ofthe cutting operation, it will become non-yielding after a certain stage in the cutting operation has been reached. The stop for determining the dimension of the finished stock cooperates with the steady rest in such way as to prevent the same from becoming locked until after the stop has functioned. The steady rest embodies means for adjusting the same to various sizes of cut without having to change the position of the magnet or other locking means. Furthermore, the steady rest will only operate 'as' a non-yield'- ing support for the stock when the carriage is in its fully advanced position against the stop, and it will lock and unlock automatically at the proper moment in the operation of the carriage.

ln the form of the invention used herein for thD purpose of exemplification, an elec trically energized magnet is employed as the locking means for rendering the steady rest non-yielding, but it will of course be appreciated that the locking of the steady rest may be accomplished in many other ways. lVhile the steady rest is shown in its application to an automatic wood-turning lathe, it will lof course be evident that it may be employed with other kinds of turning machines.

I claim:

1. A steady rest for use with a lathe, comprising a movable member adapted to bear against the rotating stock, means for supporting the said movable member While .per mitting the member to yield in a direction away from the axis of the stockrand means for preventing the member from yielding when advanced toward the axis Aof the stocli to 'a predetermined point.

2. A steady rest for use with a lathe, comprising a member adapted to bear against the rotating stock, yielding means for causing the member to move toward the aXis of the stock as the diameter of the stock is reduced in the lathe, and means for preventing the member from backing up after it has reached a predetermined point in its m'o'vement toward the axis of t-he stock.

3. A steady rest for use with a lathe, comprising a resiliently yieldable member adapted to bear against a piece of rotating stock being reduced in diameter in the lathe, `and means for holding the member against yielding movement as soon as it begins to bear on a portion of the surface of the stockthat has been reduced to a predetermined diameter.

1l. A steady rest for use with a lathe, comprising a member adapted to bear lagainst the rotating stock, yielding means for causing the member to move toward the axis of the stock as the diameter of the stool: lis reduced in the lathe, means for holding the member against yielding movement when it reaches a predetermined position, and means to adjust the member to various depths of cut without disturbing the holding means.

5. A steady rest for use with a lathe, 'coiprising a member, a spring for causing the member to move toward the rotating stock, which spring also allows the member to yield away from the stock, and means for preventing the member from yielding when the member reaches a certain point in its movement.

6. A steady rest for use with a lathe, comprising a member, means for causing the member to move toward the rotating stock, means for holding the member against movement, and stops for governing the relative movement one toward the other of the stock and the cutter, the engagement of which stops determines the operation of the holding means.

7 A steady rest for use with a lathe, comprising a member, yielding means for causing the member to move toward the rotating stock, and means for automatically holding the member against yielding movement when it reaches a predetermined position.

8. A steady rest for use with a lathe, comprising a member, yielding means for causing the member to move toward the rotating stock, means for holding the member against yielding movement, means for causing relative movement one toward the other of the stock and the cutter, and means for automatically releasing the member when the stock is withdrawn form cutting position.

9. A steady rest for use with a lathe, comprising a shaft, a stock-engaging arm journaled on the shaft, a cam-engaging arm secured t`o the shaft, means for securing the stock-engaging arm to the cam-engaging arm in various angular adjustments, a cam for swinging the cam-engaging arm to withdraw the stock-engaging arm from the stock, a magnet-engaging arm also secured to the shaft, an electrically energized magnet for holding the magnet-engaging arm, and means for automatically energizing the magnet when the stock-engaging arm has come into engagement with a portion of the surface of the stock that has received the full depth of cut.

10. In a lathe, the combination with a rotating cutter for operation upon a piece of rotating stock, and means for bringing the cutter and the stock together to reduce the size of the stock at a certain point, of a member adapted to bear against the surface of the stock at the point where it is being reduced, means for supporting the said member` While permitting the member to yield in a direction away from the axis of the stock at one stage of the cutting operation, and means for preventing the member lfrom yielding at another stage of the cutting operation.

11. In a lathe, the combination With a rotating cutter for operation upon a piece of rotating stock, and means for bringing the cutter and the stock together to reduce the size of the stock at a certain point, of a member adapted to bear against the rotating stock, yielding means for causing the memreceived the full depth of cut.

In testimony whereof I have hereunto subscribed my name.

DAVID TURCOTT.

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