US2271773A

US2271773A - Draw bench

Info

Publication number: US2271773A
Application number: US369315A
Authority: US
Inventors: Edwin J Mcilvried
Original assignee: Vaughn Machinery Co
Current assignee: Vaughn Machinery Co
Priority date: 1940-12-09
Filing date: 1940-12-09
Publication date: 1942-02-03
Anticipated expiration: 1959-02-03

Description

Feb. 3, 1942. E. J. MCILVRIED DRAW BENCH 3 Sheets-Sheet l ATTORNEY5 Filed Dec. 9, 1940 I QM.

Lil l1 Feb. 3, 1942. E. J. MCILVRIED DRAW BENCH Filed D60. 9, 1940 3 Sheets-Sheet 2 Illllli R w LN m m M6 [W W M paratus embodying my invention;

Patented Feb. 3, 1942 UNITED STATE DRAW BENCH Edwin J. Mcllvried, Stow, Ohio, assignor to The Vaughn Machinery Company, Cuyahoga Falls, Ohio, a corporation of Ohio Application December 9, 1940, Serial No. 369,315

Claims.

This invention relates to drawing apparatus and more particularly to drawing apparatus of the kind known as a draw bench and which has a carriage adapted to travel away from and toward a die support.

An object of the invention is to provide an improved draw bench having novel means by which the carriage can be quickly returned after a drawing operation and can be brought to a stop without likelihood of colliding with the die support.

Another object of my invention is to provide improved drawing apparatus, of the character mentioned, in which the return movement 01 the carriage is limited or stopped by the tautening of a length of cable having one end connected with the carriage and its other end anchored.

Still another object of my invention is to provide improved drawing apparatus, of the type referred to, wherein the means for returning the carriage after a drawing-operation involves the use of a winding drum and a novel arrangement of cables, one of which has one end connected with the carriage and its other end anchored on the drum and is of a length to be tautened by the return movement for stopping the carriage just short of engagement with the die support.

A further object of my invention is to provide improved drawing apparatus of the character mentioned, which contemplates the use of a for slowing the return movement of the ear winding drum and a pair of cables for returning the carriage and in which, one of the cables is anchored to'the drum and is of a length to limit the return movement'and the other cable extends over a yieldable take-up device in passing from the drum to the carriage. 7 I

The invention may be further briefly sum-' marized vas consisting in certain novel combinations and arrangements of parts hereinafter 'described and particularly set out in the appended In the accompanying sheets of drawings,

Fig. l-isa side elevation showing drawing ap- Fig. 2 is aplan View thereof;

Fig. 3 is a partial plan view, with portions in section, showing the winding means for taking up the v fcablesused in returning the carriage;

, 41s a vertical sectional view taken throughthe drum' and its driving means substantially as indicated by line H of Fig. 3; I

Fig; 5 is an elevation, with portions broken Fig. 6 is a side elevation showin a yieldable take-up device for removing slack from the cables;

Fig. 7 is an end view Of the take-up device, with portions thereof shown in section; and

Fig. 8 is a partial sectional view taken through tliie winding drum as indicated by line 88 of F g. 3.

Further reference will now be made to the accompanying drawings for the purpose of describing in detail the construction and operation of one embodiment of my improved drawing apparatus, but it will be understood, of course, that the invention is not limited to the particular apparatus here disclosed since it may be embodied in various other forms and arrangements of similar apparatus.

In Figs. 1 and 2 I show a draw bench It to which my novel carriage return means has been applied. The draw bench shown in this instance comprises anv elongated frame I I havin a die mount or support I2 adjacent one end thereof and also having a carriage l3 which is movable along the frame in a direction away from the die support during a drawing operation and toward the die support during the return movement following the drawing operation. The carriage l3 may have a gripping means I4 thereon for gripping the leading endv of a work piece, such as the metal bar l5 shown -in this instance, and the die support l2 may have. a die. l6 thereon through which the bar IS/is drawn .by the movement of the carriage.

' Drawing movement, that is, movement away from the die support l2, may be imparted to the carriage 13 by any suitable means. In the apparatus here illustrated a traveling chain I1 is employed for this purpose and the carriage I3 is provided with a hook l8 which is engageable in the chain for connecting the carriage therewith. The chain I! may extendaround sprockets 20 and 2| provided adjacent the ends ofthe frame II and may be propelled by suitable driving means connected with the shaft 22 of the sprocket 20. This driving means may comprise an electric motor 23'. which is connected with the shaft 22 through a reduction gear 24. At the end of the outward or drawing movement of the carriage I3, the gripping jaws i4 release the work piece l5 and the hook I8 is disconnected from the chain, as by engagement of the carriage with the slopinghousing 25, whereupon away, showing means for actuating limit switches the carriage is ready to be returned to a point adjacent the die'support ing operation.

Inasmuch as the draw bench "may be of considerable length, it is desirable to return the carriage I3 rapidly so as to save time, but returning the carriage rapidly increases the danger of damage to the apparatus due to collision of the carriage with the die support l2. The novel carriage return means which I have provided and which will now be described in 'detail enables the carriage [3 to be returned rapidly and at the same time substantially eliminates all likelihood of the carriage colliding with the die support. This carriage return means comprises a winding drum 21 and a pair of

cables

23 and 29 connected with the carriage l3. As will be presently, explained more in detail, the cable 23 is arranged to be taken up by the drum 21 for imparting the return movement to the carriage. The cable 23 has one end connected with the carriage l3 and its other end suitably anchored andis of a length such that when the carriage arrives at a point adjacent the die support l2, as shown in Fig. 1, this cable will be tautened and will stop the'return movement thereby preventing the carriage from colliding with the die support. The outer end of the cable 29 is anchored preferably, though not necessarily, by being connected with the winding drum 21.

In the arrangement here shown for the carriage return means, the cable 28 extends longitudinally beneath the frame II and around an idler pulley or sheave 30 and has its inner end connected with the carriage, as indicated at 3|. The other or outer end of this cable passes on to l2 for the next draw- 1 the winding drum 21 at the'underside thereof and is anchored on the drum adjacent one end of the winding groove 32, as indicated at 33. The cable 22 extends longitudinally above the frame II at one side of the chain 11 and. has its inner end connected with the carriage l3, as indicated at 34. The outer end of this cable passes on to the winding drum 21 at the top' thereof, that is, at the side opposite the cable 28 and is anchored on the drum at the opposite end of the winding @5 groove 32, as indicated at 35.

With the cable arrangement just described, it will be seen that when the winding drum 21 is rotated in a clockwise direction, as seen in Fig.1, the cable 28 will be wound onto the drum and at the same time the cable 28 will be unwound or payed out. During the drawing operation in movement of the carriage l3. In the present embodiment I show for this purpose a drive shaft 33 to which the drum21 is keyed or otherwise connected, and an electric motor 31 drivingly connected with said shaft by means of the pinion switch 42 which controls the energization of the motor 31- and a limit switch 43 which controls the operation of a brake 44, such as a magnetic brake, arranged to act on the shaft of the motor 31. The limit switches 42 and 43 may be actuated at the proper time by any suitable means, such as earns 45 and 43, carried by a rotatable wheel '41. This wheel may be driven in timed relation to the rotation of the winding drum 21 and the return movement of the carriage I3 by suitable means such as a pinion 43 mounted on a projection or extension 360 of the shaft 3 and meshing with a gear 49 which is formed on or connected with the wheel 41. l a

The wheel 41 and the gearing for driving the same are so constructed and arranged that the wheel will make only one revolution, or slightly less than one revolution, during the return travel V of the carriage l3.

The cams 45 and 48 are located on the wheel 41 so that when the carriage l3 approaches the die support l2, but is still some distance therefrom, the cam 45 will trip the arm III of the limit switch 42 to thereby deenergize or partially deenergize the motor 31 and this will result in a slowing down of the carriage. As the carriage moves closer to the die support, the cam 48 engages the trip arm II thereby actuating the limit switch 43 and causing the brake 44 to be applied. The application of the brake 44 slows the return movement of the carriage I3 so that by the time the cable 23 is fully unwound from the drum 21 and is stretched taut. the speed of the carriage will be relatively slow and the cable will notbe subjected to a violent jerk. If desired the cams 4B and 48 may be individually adjustable on the wheel 41 to permit of some adjustment of the timing of. the actuation of the switches 42 and 43. To this end the wheel .may have circumferential T-slots 41a in which the cams can be shifted to the desired setting.

When the outer end of the carriage 29 is anchored on the winding drum 21, as indicated at 3!, the connection between the cable and drum may be formed by providing the latter with a in the opposite or counterclockwise direction by 00 tep or recess 52, as shown in Fig. 8, and the end a power means to be presently described causing the cable 28 to be taken up or wound on the drum port 12, this cable will be entirely unwound from the drum and will become tautened and will limit or stop further return movement of the carriage thus-preventing collision of the same against the die support.

The winding drum 21 may bedriven by any suitable power means for causing the return 1| of the cable may be provided with an eye I3 through which an anchor bolt 54 extends. The step or recess 52 is located adjacent the end of the winding groove 32 so that the portion of the cable extending away from the eye 53 will readily engage in the groove when the drum 2] is rotated in a direction to wind up the cable 29.

It will be seen from Fig. 8 that when aportion of the cable 20 is wound on the drum 21, the cable will extend away from the drum alongia line which is substantially tangent to thedrum surface, as indicated in dot and dash lines, but when the cable has been fully unwound from the drum, as shown in full lines, the eye 33 occupies a position substantially opposite the drum shaft 98 and the cable is no longer tangent to the drum. The angular movement of the anchor bolt 54 from its broken line position to its full line position. as indicated in Fig. 8, thus causes a sudden increase in the rate at which the cable 29 is being payed out and would result in a slackening oi the cable if some means were not provided to compensate for this effect. To prevent such a sudden slackening of the cable 29, I provide a yieldable take-up device 56 adjacent the winding drum 2! and over which the cable 28 passes. This take-up device may comprise a suitable frame 51 having a pair of fixed sheaves or

idler pulleys

58 and 59 thereon and a travelingor movable sheave 60. The cable 28 passes from the winding drum 2'! around the movable sheave 60 and then around the stationary sheave 58 before passing forward to the carriage I3. The sheave 59 serves merely as a fair lead or guide over which the cable 29 passes. A guard 6| may be located adjacent the sheave 59 to retain the cable 29 thereon.

The movable or traveling sheave 60 may be carried by a swinging lever or arm 52 having a pivotal connection 63 on the frame and hav- 1 ing its free end guided by the arcuate slot 63a.

A compression spring 64 is arranged between the swinging lever 62 and an arm or bracket 65 of the frame so that a pulling force applied to the cable 28 will tend to compress the spring and any sudden tendency for either the cable 28 or the cable 29 to slackenwill be quickly taken up by the expansive action of the spring 64 moving the swinging lever 62 and the sheave 60 away from the sheave 58. Since both of the

cables

28 and 29 are connected with the drum 2] and with the carriage l3 and the'latter is movable along the track, it will be seen that the spring actuated sheave 60 over which the cable 28 passes will serve to take up slack in both cables. If slack should occur in the cable 29, the spring 56 acting through the cable 28 would move the carriage along its track a distance suflicient to take up such slack in the cable 29.

Oneend of the spring 64 may bear against a seat 66 which is pivoted to the arm 65 and the other end may bear against a seat 61 which is pivoted to the swinging lever 62. For maintaining the

seats

66 and 61 in proper alignment with each other, I may provide the seat 66 with an extension 68 having spaced bearings 69 and I0 thereon and may provide the seat 61 with an extension in the form of a rod H which is slidable in the bearings 69 and 10. As shown in. Fig. 6 the stationary sheave 58 may be mounted in an inclined position so that the portion of the cable 28 extending forward to the carriage I3 may clear the movable sheave 60.

From the foregoing description and the accompanying drawings, it will now be readily understood that I have provided an improved draw bench having novel carriage return means which permits the carriage to be rapidly returned after a drawing operation and insures a positive stopping of the carriage without colliding with the die support.

While I have illustrated and described my improved draw bench in a more or less detailed manner, it will be understood, of course, that I do not wish to be limited to the particular details of construction and arrangements of parts herein disclosed, but regard my invention as includingsuch changes and modifications as do not constitute a departure from the spirit of the invention and the scope of the appended claims.

Having thus described my invention, I claim: 1, In a draw bench having a die mount and a carriage movable relative thereto, means for moving the carriage away from the. die mount during a drawing operation, means for returning the carriage toward the die mount after a drawing operation, and means for limiting the return movement of the carriage comprising a cable having one end connected with the carriage and its other end anchored.

2. In combination with a draw bench'having a die mount and a carriage movable relative to said die mount, means for moving the carriage away from the die mount during a drawing operation, means for returning the carriage comprising a cable connected therewith and a winding drum for taking up the. cable, and means for limiting the return movement of the carriage comprising a cable having one end connected with the carriage and its other end anchored.

3. In a draw bench having a die mount and a carriage movable relative thereto, means for moving the carriage away from the die mount during a drawing operation, means for returning the carriage toward the die mount after a drawing operation, switch-controlled means for slowing the return movement of the carriage as it approaches the die mount, and means for limiting such return movement comprising a cable having one end connected with the carriage and its other end anchored.

4. In a draw bench having a die mount and a carriage movable relative thereto, means for moving the carriage away from the die mount dufring a drawing operation, a winding drum, means for driving said drum, a cable connected with the carriage and arranged to be taken up by the drum for returning the carriage toward the-die mount, and a length of cable having its drum being rotatable in the reverse direction to' pay out said cable during the drawing operation, and a second cable having its ends con- I nected respectively with said carriage and drum said cables and over and being of a length to limit the return movement of the carriage, said second cable being arranged to be taken up by said drum during its reverse rotation and to be unwound therefrom during said return movement of the carriage.

6. In a draw bench having a die mount and a carriage movable relative thereto, means for moving the carriage away from the die mount during a drawing operation, a winding drum. means for driving said drum, a cable connected with the carriage and arranged to be taken up by said drum for returning the carriage toward the die mount, a second cable having one end connected with the carriage and its other end anchored on the drum and being of a length to limit the return movement of the carriage, and yieldable take-up means adapted to take up slack in which the first-mentioned cable passes.

I. In apparatus oi the character described,

an elongated frame having a die support adia! cent one end thereof, a die on said support, a carriage movable along said frame and provided with a work gripping means, means for moving the carriage away from said die support for drawing work through said die, a winding drum adjacent the other end of said frame, a sheave adjacent said one end of the frame, a cable extending around said sheaveand having its ends connected with said carriage and said winding drum, means for driving .said drum for takup said cable and returning the carriage toward the die support, and a second cable. having one end anchored and its other end connected with said carriage and being of a length to stop the return movement of the carriage just short of engagement of the carriage with the die support 8. Inapparatus of the character described, an elongated frame having a die support adjacent one end thereof, a die on said support, a carriage movable along said frame and provided with a work gripping means, means for moving the carriage away from said die support for drawing work through said die, a winding drum adjacent the other end 01' said frame, a sheave adjacent said one end of the frame, a cable extending around said sheave and having its ends connected with said carriage and said winding drum, means for driving said drum for taking up said cable and returning the carriage toward the die support, switch-controlled means for slowing the return movement of the carriage as it approaches the die support, and means for stopping such return movement just short of en- 'riage and the other end anchored on the drum and being of a length such that it will be fully unwound from the drum and tautened to check the return movement of the carriage before the latter reaches the die support.

10. In combination with a die support and a carriage movable away from the die support during a drawing stroke and toward the die support during the return stroke, a traveling chain for propelling the carriage during the drawing stroke,

a winding drum spaced from said die support, a cable connected with said carriage and adapted to be taken up by the drum for propelling the carriage during its return stroke, and a second cable for limiting the return stroke to prevent the carriage from striking the die support, said second cable having one end connected with the carriage and the other end anchored on the drum and being of a length such that it will be fully unwound from the drum and tautened to check the return movement of the carriage before the latter reaches the die support.

EDWIN J. McILVRIED.