US1761739A - Spring-coiling machine - Google Patents

Description

June 3, 1930.

- M. NlgRo 1,761,739

SPRING COILiNG MACHINE Filed Nov. 1. 1928 2 Sheets-Sheet '1.

M76724 jig/'0 June 3, 1930. Y M, eRo 1,761,739

SPRING COILING MACH-INE Filed Nov. 1, 1928 2 Sheets-Sheet 2 .1 a Mk6! Jay/0 Patented June 3, 1930 UNITED STATES PATENT OFFICE MICHEL NIGRO, OF WORCESTER, MASSACHUSETTS, ASSIGNOR TO SLEEPER & HARTLEY, INC, OF ,WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS SPRING-OOILING' mcnmn My invention relates to machines for forming or coiling wire springs, particularly coiling machines of the type employing feed rolls for positively feeding the wire to a stationary coiling point where it is deflected around an arbor into a coil of the desired size and form.

A machine of this general type is shown and described in Patent No. 1,266,070 issued May 14, 1918, to Frank H. Sleeper, and the object of the present invention is to provide a spring coiling machine of this type with an improved arbor and coiling and cutting instrumentalities co-operating therewith whereby springs may be coiled and out having a very much smaller internal diameter than any springs that it has been heretofore possible to coil and cut on existing machines. Furthermore, my improved arbor is so designed that it possesses very great strength for its size and is able to withstand the strains imposed upon it by the impact of the cutting tool each time a spring is severed. The above and other advantageous features of my invention will hereinafter more-fully appear with reference to the accompanying drawings in which- Fig. 1 is a general View in front elevation of a portion of a spring coiling machine provided with an arbor and tools embodying my invention.

Fig. 2 is a fragmentary view illustrating on an enlarged, scale the spring coiling and cutting tools co-operating with my improved arbor.

Fig. 3 is a horizontal sectional view along the line 3-3 of Fig. 1, looking in the direction of the arrow.

Fig. 4 is a perspective view of the tool holder with my improved arbor carrled thereby. I

Figs. 5, 6 and 7 are enlarged detailed vlews of the arbor removed from its holder.

.Fig. 8 illustrates the formation of a coil on the arbor.

Fig. 9 is a perspective View of the coiling point removed from the machine.

Fig. 10 is aperspective view of the pitch tool removed from the machine.

Like reference characters refer to like parts throu bout the drawings.

Re erring to the drawings, particularly Fig. 1, the machine generally comprises a housing upon which are mounted airs of co-operatlng feed rolls 2, 2 and 3, 3 w ich are adapted by their rotation to grip the wire 4 and positively feed it through grooved wire guides 5 and 6 to the coiling tools.

' The particular mechanism for driving the' rolls 2 and 3 to feed the wire 4 forms no part of the present invention, but is fully shown and described in the aforesaid Sleeper Patent N 0. 1,266,070. Sufiice it to say for the purposes of the present invention that the two pairs of feed rolls 2 and 3 are geared together for synchronous, rotation and are riven intermittently from a suitable source of power to feed the wire 4 step by step to the coiling devices which will now be described. Referring now to Fi 2 it will be seen that as the wire 4 emerges rom between the lefthand guides 6 under the urge of the feeding rolls2 and 3, it will be partially received in a groove 7 provided in the lower edge of an auxiliary guide 8. The wire 4; will then pass over the coiling nose 9 of my improvedarbor 10 to the coiling point 11 which will deflect the wire downwardly around thenoee 9 when a righthand spring is being coiled. As the wire is fed and coiled on the arbor 10, the proper pitch is imparted to the convolutions of the helix by a pitch tool 12.

When enough wire 4 has been fed by the rolls 2 and 3 to form a coil of the desired length, the rotation of the feed rolls 2 and 3 is interrupted, whereupon a cutting tool 13 severs the completedcoil by co-operation with the stationary arbor 10. As fully described in the aforesaid Patent No. 1,266,070, the cutting tool 13 is carried by a clamp 14 on a movable head 15 that is adapted to have a 'rotative movement imparted thereto to swing the cut-- ting tool 13 in the direction of the arbor 10, the mechanism for operating the head 15 being so timed as to operate the cuttin tool 13 as soon as the wire feeding rolls 2 an 3 come to rest.

The holder 16 provides a longitudinal open ing 17 for receiving the arbor 10 and a second opening 18 parallel to the opening 17 receivesa. rod 19 for supporting the pitch tool 12. The holder 16' also provides a threaded opening 20 for receiving a bolt '21 which secures the auxiliary guide 8 to the face of the holder 16. ,7 I I Referring now to Figs. 5, 6 and 7, the arbor 10 consists of a cylindrical body portion of suitable diameter to be received in the opening 17 of the tool holder 16, a slot 17 intersecting the opening 17 to permit the material of the holder to be compressed around the cylindrical body portion of the arbor 10 to hold it firmly in position. Each end of thearbor 10 provides a web 22 of uniform thickness, the parallel faces 22 of the web 22 being joined at one end of the web 22 by a rounded surface 23 which extends at right angles to the end face 24 of the arbor body. The coiling nose 9 is formed at theend of the rounded surface 23 by beveling the edge of the,web 22 to. provide a shoulder 25 around which the wire is deflected as shown in. Fig. 8, when forming the smallest coil. The bevel 26 merges at one end of the web 22 with the rounded surface of the cylindrical body portion, the bevel serving to direct the wire as it passes around the nose 9 when forming coils of difierent diameters. By reason of the construction of the nose 9 it is possible to form a coil, the internal diameter of which is not more than one and one-half times the diameter of the wire from which the coil is being formed, as shown in Fig. 8.

It is also apparent from -aconsideration of Fig. 5 that the construction of the arbor 10 is such as to provide the maximum degree of strength for the nose 9 on which the coiled wire is cut by the tool 13 striking through to the sharp edge 27 between the rounded end surface 23 and the lower flat web face 22.

. The web portion extending across the arbor face 24 has a length several times the diameter of the nose 9 so that the whole area at the base of this web 22 will have to be sheared off in order to break off the nose 9 when it receives the impact of the cutting tool 13. The arbor 10 is provided with a web 22 at each end, thenoses 9 facing in opposite directions so that when the arbor 10 is reversed, the nose 9 will face properly for the formation of a 'left-hand coil. v

As best shown in Fig. 10, the pitch tool 12 is adapted to be set closely to the Web 22 of the mandrel 10 when coiling springs of small diameter, the upper edge of the tool 12 providing a depression 28 which is adapted to receive a portion of the web 22 when the pitch tool 12 is turned on its supporting rod 19 in the position shown in Fig. 2. The position of the pitch tool 12 with respect to the arbor 10 and coiling point 11 is adapted to be controlled in the manner set forth in the aforesaid Patent No. 1,266,070'and it is therefore believed to be unnecessary to go into further detail regarding this particular mech-' anism which forms no part of the present invention.

Referring now to Fig. 9 the coiling point 11 is shown provided with a groove 29 at each end thereof to receive the wire 4 as it is deflected around the coiling nose 9, each end of the tool. 11 being beveled in two planes to provide clearance for the cutting-tool 13 to swing in close to thenose 9 when severing a completed spring. The coiling point 11 is secured by a clamp 30 to a block 31 which is carried by a pin 32 projecting from a slide 33 as shown in Fig. 3. The slide 33 is adapted to be moved with respect to the arbor or man drel 10 by means of an arm 34 for the purpose of varying the diameter of the springs being coiled.

From the foregoing, it is apparent that by my invention I have provided a spring coiling.

machine embodying an improved arbor on which springs of very small diameter may be coiled and out. By means of my arbor it is possible to coil and cut springs which have an internal diameter of not more than one and one-half times the diameter of the wire stock being coiled. Furthermore, my improved arbor is so constructed that the nose about which a wire is actually coiled is formed integrally with a web which serves to' around which wire is adapted to be de ected into a spiral having an internal diameter of less than twice the diameter of the wire being coiled.

2. In a machine of the class described, a coiling arbor providing at its end a projecting web having a rounded end and parallel faces, one of said faces being beveled to provide a shoulder opposite to said rounded end around which shoulder the wire is deflected in coiling.

3. In a machine of the class described, a coiling arbor providing at its end a projecting web having a rounded end and parallel faces, one of said faces being beveled to provide a shoulder around which the wire isdeflected in coiling, with the junction between said beveled face and said rounded end probe severed.

4. In amachine of coiling arbor comprisinga cylindrical body which provides a web of portion, one end of substantially unifor the class described, a

thickness, the parallel faces of said web being joined at one end by 5 a rounded surface extending at right angles to the end face of the a face of the web beveledrbor body, with one to provide a'shoulder around which the Wire is deflected in coilmg.

MICHEL NIGRO.

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