US3333448A

US3333448A - Powered metal spinning apparatus

Info

Publication number: US3333448A
Application number: US118342A
Authority: US
Inventors: George H Ikert
Original assignee: Calumet and Hecla Inc
Current assignee: Calumet and Hecla Inc
Priority date: 1961-06-20
Filing date: 1961-06-20
Publication date: 1967-08-01
Anticipated expiration: 1984-08-01
Also published as: GB984662A

Description

6. H. iKERT POWERED METAL SPINNING APPARATUS Aug 1, 1967 2 Sheets-Sheet 1 Filed June 20, 1961 1, 1967 G. H. iKERT 3,333,448

POWERED METAL SPINNING APPARATUS Filed June 20, 1961 2 Sheets-Sheet 2 J 1/5 110 701 J06 23 o J 512 INVENTOR,

J05 J10 6205 96 Zlfwr' United States Patent POWERED METAL SPINNING APPARATUS George H. Ikert, Elgin, 11]., assignor to Calumet & Hecla,

Inc., Chicago, Ill., a corporation of Michigan Filed June 20, 1961, Ser. No. 118,342 The portion of the term of the patent subsequent to June 13, 1981, has been disclaimed 6 Claims. (CI. 72-85) This invention relates generally to methods of formmg metals and especially to metal spinning.

Metal spinning has been practiced for centuries, and the utility of this metal forming process is attested to by the extent to which it is employed, essentially unchanged, even in our modern age of automation. Metal spinning is generally considered to be an art or craft exacting manual skill, judgment, physical strength and endurance considerably beyond that required of an operator in other metal forming processes. Reduced to its rudiments, metal spinning entails the pressing of a tool against the side of a spinning metal blank according to a deliberate sequence until the originally flat blank is completely formed against a volumetric chuck. Since the wall thickness of the blank can be either increased or decreased during spinning, the operator must retain tactile contact with the forming metal in order to control the wall thickness of the finished part. As the original thickness and temper of the metal blank is increased, so also are the physical demands on the operator, especially if he is to maintain his feel of the forming metal. Compound spinning apparatus has .been developed, employi ng a lever arrangement for multiplying the operators physical efforts; however, even this apparatus imposes appreciable demands on the operators strength and endurance during an ordinary work shift.

Accordingly, an important object of the present invention is to provide metal spinning apparatus incorporatmg power assistance for movement of the spinning tool and ensuring tactile perception of the forming of the workpiece.

A more general object of the invention is to provide new and improved metal spinning apparatus.

Another object of the invention is to provide metal spinning apparatus that places but small physical demands on the operator.

Yet another object of the invention is to provide powered metal spinning apparatus that uses the normal spinning skills and techniques.

Additional objects and features of the invention pertain to the particular structure and arrangements where- ,by the above objects are attained.

Spinning apparatus in accord with the invention includes a tool rest, a fulcrum lever pivotally mounted on the tool rest, a spinning lever pivotally mounted on the fulcrum lever and carrying a spinning tool thereon, hydraulic acks acting between the levers and the tool rest, control valves for the hydraulic jacks functioning in response to actuating forces in excess of a predetermined value, and handle elements pivotally mounted respectively on the fulcrum lever and on the spnning lever adapted for pivoting the respective lever upon application of manual force less than the predetermined value and for actuating the corresponding control valve upon application of manual force more than the predetermined value.

The invention, both to its structure and mode of operation, will be better understood by reference to the following disclosure and drawings forming a part thereof, wherein:

FIG. 1 is a perspective view of powered metal spinning apparatus constructed in accordance with the invention;

3,333,448 Patented Aug. 1, 1967 FIG. 2 is a schematic plan view of the levers and hydraulic arrangements used in the apparatus of FIG. 1;

FIG. 3 is a schematic view of the spinning lever, the associated hydraulic jack and the control valve for the jack, the valve spool in the control valve being shown in the neutral position in which no actuation of the jack piston is realized;

FIG. 4 is a view similar to the showing of FIG. 3 with the several parts rearranged for powered movement of the lever to the right as viewed in the drawing; and

FIG. 5 is a view similar to the showing of FIG. 3 but with the parts rearranged for powered movement of the lever to the left as viewed in the drawing.

Referring now in detail to the drawings, particularly to FIGS. 1 and 2, a powered metal spinning apparatus will be seen to comprise a lathe machine 10 including a rotatable drive head 12 receiving motive force from. an electric motor 14. A volumetric chuck 16 is mounted to the drive head 12, and a metal blank 18 is held securely against the chuck 16 by means of a tail block 20. A tool rest arrangement shown generally at 22 is fixed to the lathe machine 10 spaced laterally apart from and parallel to the common axis of head 12, chuck 16 and tail block 20. The tool rest arrangement 22 includes an elongated member 24 having laterally formed

extensions

26 and 28 rigidly fastened at its end. i

A dog-leg-shaped, compound or fulcrum lever 30 is pivotally mounted to the member 24 intermediate its ends. Advantageously, the compound lever 30 overlies the member 24 and is pivotally connected thereto by means of a pin 32 entering aligned bores in the lever 30 and the member 24. As will be recognized, pin 32 may be prevented-from axial movement relative to the lever 30 by heading, by provision of a collar, or other suitable means. In addition, the drilling of a series of holes in the member 24 permits considerable adjustment in the position of the compound lever relative to the workpiece.

A roll or spining lever 34 is pivotally mounted on the offset end portion of the compound lever 30 by means of a pin 36 entering aligned bores in the respective levers. As will be recognized, certain variation in the leverage applied by the interaction of the levers can be achieved by repositioning the spinning lever 34 along the offset end portion of lever 30. The lever 34 carries a spinning tool 38 on which is nearest the workpiece; and while a wheel-like tool has been illustrated, any type of spinning tool may be used.

In accordance with an important feature of the invention, an arrangement of hydraulic cylinders and valves is provided for supplementing an operators manual manipulation of the

levers

30 and 34. Specifically, a double-acting hydraulic jack 40 operates between the spinning lever 34 and the extension 28 of the tool rest. Similarly, a double-acting hydraulic jack 42 operates between the compound lever 30 and the extension 26.

As is particularly well shown in FIG. 2, the hydraulic jack 40 includes a cylinder 44 that is swingably mounted to the lever 34 by means of an arm 46 and a pivot st-ud 48. The jack 40 also includes a piston 50 having a piston rod 52 fixed thereto. At the end of rod 52 away from the piston 50, a coupling 54 swingably mounts the jack 40 to the extension 28. In similar manner, the jack 42 includes a cylinder 56 which is swingably mounted to lever 30 by means of an arm 58 and a pivot stud 60, the jack 42 also including a piston 62 and a piston rod 64. The piston rod 64 is appropriately swingably mounted to the extension 26 by means of a coupling 66.

Hydraudic fluid is supplied to the

jacks

40 and 42 from a pump 68, pump 68 withdrawing fluid from a reservoir 70 that is associated with the return hydraulic lines.

The operation of each of the

hydraulic jacks

40 and 42 is regulated and directed by a control valve arrangement,

control valve arrangements

72 and 74 respectively. These hydraulic control valves are actuated by

handles

76 and 78 respectively, the handle 76 being pivotally mounted to the spinning lever 34 at 80 and being connected to the operating member of valve 72 by the ball stud 82. Handle 78 is pivotally connected to the compound lever 30 at 84 and is arranged to actuate the operating member of valve 74 through a ball stud 86.

Detailed descriptions of the construction of control valve 72, of the hydraulic connections between valve 72 and jack 40, and of the operation of these elements will now be given with reference to FIGS. 3-5.

The control valve 72 will be seen to comprise a valve body or housing 90 that is provided with a threaded bore 93 opening from one end. An L-shaped arm 94 is welded or otherwise rigidly fastened to an extension 96 of spinning lever 34; and the free end of arm 94 is appropriately threaded for progressive engagement with the threaded bore 92 and resultant rigid attachment of the valve body 90 to the spinning lever 34.

The valve body 90 is fashioned with a central bore 98 in which a valve spool 100 reciprocably operates. The valve body also defines a pair of

passageways

102 and 104 communicating with a common conduit 105 which leads to the pump 68. The valve body 90 also defines a pair of

passageways

106 and 108 situated approximately diametrically to but offset slightly from the

passageways

102 and 104,

passageways

106 and 108 communicating respectively with the jack cylinder 44 on opposite sides of the piston 50. Passageways 106 and 108 specifically communicate with the cylinder 44 through

conduits

110 and 112 respectively. The valve body 90 is further fashioned with a radial cavity 114 opening into the bore 98 intermediate the

passageways

106 and 108. A passageway 116 opens into bore 98 diametrically from cavity 114 and is connected to reservoir 70 by a conduit 118.

The spool 100 includes a central shaft 120 and three annular, radially extending, flange-like valve members,

valve members

122, 124 and 126. Valve member 122 is adapted for selective opening and closing of the

passageways

102 and 106; the valve member 124 is arranged for selective opening a closing of the passageway 116 and the cavity 114; and the valve member 126 is arranged for selective opening and closing of the

passageways

104 and 108. The valve spool 100 is centered in the bore 98 by means of a compression spring 128, two rigid retainer washers,

washers

130 and 132, and spaced apart, annular shoulders formed in the valve body 90 for individual cooperation with the

Washers

130 and 132.

The ball nut 82 is connected to the shaft 120 of valve spool 100 so that manually applied forces on the handle 76 tending to rotate the handle about the pivot 80 will be transmitted to the valve spool for relocation of the

valve members

122, 124 and 126. The spring 128 is advantageously selected to balance forces of approximately four pounds so that only forces in excess of that value are capable of relocating the valve spool 100. Thus, manual forces tending to rotate the handle 76 about the pivot 80 which do not exceed four pounds in total pressure do not operate the valve 72 but are transmitted directly to the spinning lever 34 for arcuate movement thereof about the pivot pin 36, fluid being transferred from one side of piston 50 to the other through cavity 114 to permit this movement. When such manual forces do exceed the value necessary to overcome the spring 128, the valve spool is relocated to result in jack 40 providing power assistance to the desired movement of the lever 34.

' The neutral position of valve 72 in which there is no actuation of jack piston 50 is shown in FIG. 3. There, it will be observed, the valve member 124 is in blocking relationship relative to the passageway 116 preventing any return of hydraulic fluid to the reservoir 70. In addition, the valve member 122 is positioned opening both the pas- 4

sageways

102 and 106. Similarly, the valve member 126 is disposed opening the

passageways

104 and 108. Thus,

hydraulic fluid from the pump 68 is transmitted to both sides of the piston 50 for balancing the piston and avoiding movement thereof.

Because of the pivotal arrangement of spinning lever 34, desired movement of the lever in the direction indicated in FIG. 4 by arrow 134 is realized by urging the handle 76 in the direction indicated by arrow 136. When the force imposed upon the handle in the direction of arrow 136 exceeds the spring pressure of spring 128, the valve spool moves to the right as shown in FIG. 4. As a result of this movement, the valve member 122 blocks the passageway 102 and the valve member 124 opens the passageway 116 to the return line to the reservoir 70. As the conduit is thus evacuated, the fluid pressure from pump 68 passing through the

passageways

104 and 108 and into the conduit 112 urges the piston 50 in the direction of arrow 138 providing power assistance for the desired movement of the lever 34.

FIG. 5 shows the arrangement of valve 72 for power assistance in movement of the lever 34 in the direction indicated by arrow 140. Upon movement of the handle 76 in the direction indicated by arrow 142 with such force as to overcome the spring 128, the valve spool 100 is resituated as shown. Valve member 126 opens passageway 108 to communication with passageway 116 around the lands of valve member 124, valve member 126 simultaneously closing off passageway 104. In addition, valve member 122 is positioned in non-obstructing relationship relative to the

pasageways

102 and 106. Thus, return flow of hydraulic fluid from the right side of piston 50 through the conduit 112 and to the reservoir 70 is incurred; and the fluid pressure from pump 68 is transmitted through the

passageways

102 and 106 and through the conduit 110 to the left hand side of the piston 50 as viewed in FIG. 5. As a result, the piston will be displaced in the direction of arrow 144 to provide power assistance to the movement of lever 34 in the direction of arrow 140.

As will be recognized, any time in the course of the manipulation of lever 34 that the force imposed on the handle 76 falls below that necessary to overcome the spring 128, the spring will center the spool 100 in the neutral position illustrated in FIG. 3 whereupon manual control of the lever will be realized. On the other hand, when the manual forces imposed upon handle 76 exceed the spring pressure in either direction, force from the hydraulic jack 40 will be developed causing the desired movement of the spinning lever.

Control valve 74 is constructed and oriented similarly to control valve 72; and since jack 42 is arranged oppositely to jack 44 in accordance with the showing of FIG. 2, it will be apparent that valve 74 operates jack 42 in a manner reverse of that described immediately hereinabove for valve 72 and jack 40.

Operation of the metal spinning apparatus of the invention will be apparent from the foregoing descriptions.

It is to be recognized that the machine operator is able to maintain tactile contact with the spinning metal blank since conscious effort is necessary on his part to move the

levers

30 and 34 so as to cause the spinning tool to follow the yielding metal blank. In accordance with the invention, power assistance is available, but movement of the tool levers must be initiated by manual force outside of the hydraulic power system.

The specific embodiment of the invention herein shown and described should be considered as illustrative only. Various changes in structure will, no doubt, occur to those skilled in the art; and such changes are to be understood as forming a part of this invention insofar as they fall within the spirit and scope of the appended claims.

The invention is claimed a follows:

1. Metal spinning apparatus comprising: tool rest means; a fulcrum lever pivotally mounted on said tool rest means; first hydraulic jack means acting between said lever and said tool rest means; control valve means for said jack means functioning in response to actuating forces in excess of a predetermined value; handle means on said fulcrum lever adapted for pivoting said lever upon application of manual forces less than said predetermined value and for actuating said control valve means upon application of manual forces at least equal to said predetermined value; a roll lever pivotally mounted on said fulcrum lever and carrying a spinning tool thereon; second hydraulic jack means acting between said roll lever and said tool rest means; control valve means for said second jack means functioning in response to actuating forces in excess of a predetermined value; and handle means on said roll lever adapted for pivoting said lever upon application of manual forces less than said predetermined value and for actuating said control valve means upon application of manual forces at least equal to said predetermined value.

2. Metal spinning apparatus according to claim 1 wherein each of said control valve means includes a plurality of flow passageways communicating with the cylinder of the cooperating jack means, a valve spool selectively opening and closing said passageways and a centering spring operative to position said spool normally in a neutral position associated with inaction of said jack means.

3. Metal spinning apparatus according to claim 1 wherein said predetermined force value is approximately four pounds.

4. Metal spinning apparatus comprising: tool rest means having laterally formed, oppositely disposed terminal extensions; a fulcrum lever pivotally mounted on said tool rest means; first double acting hydraulic jack means acting between said lever and one of said terminal extensions; control valve means for said jack means functioning in response to actuating forces in excess of a predetermined value; handle means pivotally mounted on said fulcrum lever adapted for pivoting said lever upon application of manual forces less than said predetermined value and for actuating said control valve means upon application of manual forces greater than said predetermined value; a roll lever pivotally mounted on said fulcrum lever and carrying a spinning tool thereon; second double acting hydraulic jack means acting between said roll lever and the other of said terminal extensions; control valve means for said second jack means functioning in response to actuating forces in excess of a predetermined value; and handle means pivotally mounted on said roll lever adapted for pivoting said lever upon application of manual forces less than said predetermined value and for actuating said control valve means upon application of manual forces greater than said predetermined value.

5. Metal spinning apparatus according to claim 4 wherein each of said control valve means includes two flow passageways connected to the cylinder of the cooperating jack means respectively on opposite sides of the piston thereof, a valve spool selectively opening and closing said passageways, and a centering spring operative to position said spool normally opening both of said passsageways.

6. Metal spinning apparatus according to claim 4 wherein said predetermined force value is approximately four pounds.

References Cited UNITED STATES PATENTS 603,096 4/1898 Worth l1352 2,918,850 12/ 1959 Swanson et a1. -13.5 3,053,234 9/1962 Chevreux 121-41 OTHER REFERENCES Product Engineering, Jan. 5, 1959, pp 42-47.

RICHARD J. HERBST, Primary Examiner.

NEDWIN BERGER, Examiner.

K. A. COCKS, Assistant Examiner.

Claims

1. METAL SPINNING APPARATUS COMPRISING: TOOL REST MEANS; A FULCRUM LEVER PIVOTALLY MOUNTED ON SAID TOOL REST MEANS; FIRST HYDRAULIC JACK MEANS ACTING BETWEEN SAID LEVER AND SAID TOOL REST MEANS; CONTROL VALVE MEANS FOR SAID JACK MEANS FUNCTIONING IN RESPONSE TO ACTUATING FORCES IN EXCESS OF A PREDETERMINED VALUE; HANDLE MEANS ON SAID FULCRUM LEVER ADAPTED FOR PIVOTING SAID LEVER UPON APPLICATION OF MANUAL FORCES LESS THAN SAID PREDETERMINED VALUE AND FOR ACTUATING SAID CONTROL VALVE MEANS UPON APPLICATION OF MANUAL FORCES AT LEAST EQUAL TO SAID PREDETERMINED VALUE: A ROLL LEVER PIVOTALLY MOUNTED ON SAID FULCRUM LEVER AND CARRYING A SPINNING TOOL THEREON; SECOND HYDRAULIC JACK MEANS ACTING BETWEEN SAID ROLL LEVER AND SAID TOOL REST MEANS; CONTROL VALVE MEANS FOR SAID SECOND JACK MEANS FUNCTIONING IN RESPONSE TO ACTUATING FORCES IN EXCESS OF A PREDETERMINED VALUE; AND HANDLE MEANS ON SAID ROLL LEVER ADAPTED FOR PIVOTING SAID LEVER UPON APPLICATION OF MANUAL FORCES LESS THAN SAID PREDETERMINED VALUE AND FOR ACTUATING SAID CONTROL VALVE MEANS UPON APPLICATION OF MANUAL FORCES AT LEAST EQUAL TO SAID PREDETERMINED VALUE.