US3847003A

US3847003A - Apparatus for producing pigtails on hanger wires

Info

Publication number: US3847003A
Application number: US00456893A
Authority: US
Inventors: O Schaefer
Original assignee: O Schaefer
Current assignee: SLAS Inc A CORP OF TX
Priority date: 1974-04-01
Filing date: 1974-04-01
Publication date: 1974-11-12
Anticipated expiration: 1991-11-12

Abstract

For producing pigtails on hanger wires, apparatus includes a rotatable shaft having mandrels at opposite ends projecting from a frame, each having a diametral end slot. The shaft carries a fixed pinion gear, and is driven intermittently by means of a continuously rotating flywheel carrying a gear segment. An index mechanism stops rotation of the shaft after each intermittent drive, with the diametral slots oriented horizontally. Guide means guide wire segments into and through the mandrel slots, and maintain the segments in the guide path during mandrel rotation, to produce a pigtail consisting of a full loop and a return tail extending generally parallel with the wire segment. Stripper members, actuated by the flywheel, strip the hanger wires from each mandrel.

Description

United States Patent 1 [111 3,847,003

Schaefer Nov. 12, 1974 1 1 APPARATUS FOR PRODUCING PIGTAILS Primary Examiner-Lowell A. Larson ON HANGER WIRES [76] Inventor: Otto W. Schaefer, 2838 Alan-A-Dale, lrving, Tex. 75061 [22] Filed: Apr. 1, 1974 [21] App]. No.: 456,893

[52] US. Cl 72/134, 72/142, 140/104 [51] Int. Cl B2lf 3/027 [58] Field of Search 140/71, 90, 92, 102, 104, 140/124, 92.2; 72/134, 142

[56] Y References Cited UNITED STATES PATENTS 1,045,900 12/1912 Sleeper 72/142 1,673,185 6/1928 DesCombes 72/142 2,553,796 5/1951 Stussi 72/142 2,873,767 2/1959 Barnes 140/71 A Attorney, Agent, or Firm-Peter .1. Murphy [57] ABSTRACT in the guide path during mandrel rotation, to produce I a pigtail consisting of a full loop and a return tail extending generally parallel with the wire segment. Stripper members, actuated by the flywheel, strip the hanger wires from each mandrel.

9 Claims, 9 Drawing Figures PMENTEDHUV 12 mm 3,847,003

sum 1 or 2 v Fig. 2

PATENTEDNUV12 1914 sum 2 w 2 3,847,003

HUMP 60 I z y 5.9

APPARATUS FOR PRODUCING PIGTAILS ON HANGER WIRES BACKGROUND AND SUMMARY OF THE INVENTION This invention relates to semi-automatic apparatus for forming pigtails on hanger wires, for embedment in poured concrete ceiling structures.

In the construction of commercial buildings, such as multi-story office buildings, space is provided at the ceiling of each floor level for conduits for the purpose of carrying building utilities such as water and electricity; and means are provided for suspending, from the permanent ceiling structure, a false ceiling to provide for an aesthetically pleasing ceiling in the finished space. The false ceiling structure conventionally consist of a grid of supporting rails, which in turn support panels of various structure defining the aesthetically pleasing ceiling surface; and these rails also support lighting fixtures.

The means for supporting and leveling the false ceiling rails, and also for supporting the above mentioned utility conduits, are referred to as hanger wires; and these must be anchored in some manner to the permanent ceiling.

In structures where the permanent ceiling or ceilingfloor structure is of poured concrete, it is convenient to provide such hanger wires by drilling holes in the concrete forms, initially supporting the hanger wires by said forms, with the hanger wires having means not only to be retained and supported by said forms but also having means to be enveloped and permanently retained in the concrete ceiling after it is set. This invention is concerned with such means which is referred to as a pigtail formed at one end of the hanger wire, which provides an anchor to be enveloped in the concrete, and also provides means for supporting that anchor in spaced relation to the form so that it is fully enveloped by the concrete.

A principal object of this invention is to provide a novel apparatus for forming pigtails on hanger wires in a rapid and efficient manner.

Another object of this invention is to provide such apparatus which is semi-automatic in operation enabling an operator to manually feed said apparatus for automatic pigtailing.

A further object of this invention is to provide such apparatus which is available for use, when the demand requires, for pigtailing hanger wires in an efficient manner.

A still further object of this invention is to provide such semiautomatic apparatus incorporating two work stations enabling operation with two operators simultaneously if required by the demand.

For accomplishing these objects, apparatus according to the invention includes a shaft rotatably supported on a frame, having a mandrel at one end provided with a diametral slot. The apparatus includes drive means for driving the shaft intermittently through a selected number of revolutions; and the apparatus includes index means acting on the shaft to stop the rotation of the mandrel after each drive with the slot oriented in a preselected position. The apparatus includes guide means for guiding the end of an elongated wire segment into and transversely through the mandrel slot, and stop means for limiting the movement of the wire segment beyond the mandrel. The apparatus further includes stripping means for stripping the wire from the end of the mandrel, operated in timed relation with the shaft drive.

The novel features and the advantages of the invention, as well as additional objects thereof, will be understood more fully from the following description when read in connection with the accompanying drawings.

DRAWINGS FIG. I is a fragmentary illustration of a hanger wire embedded in a concrete ceiling beam prior to removal of the concrete form;

FIG. 2 is a front elevation view of a machine according to the invention;

FIG. 3 is a plan view of the machine of FIG. 2, partially broken away;

FIG. 4 is a partial rear elevation view of the machine of FIG. 2, partially broken away;

FIG. 5 is a detail view taken in the plane 5-5 of FIG. 3;

FIG. 6 is a partial elevation view of the machine from the left side;

FIGS. 7 and 8 are fragmentary plan and elevation views, respectively, of the front spindle and associated components, with wire wrapped on the spindle; and

FIG. 9 is a fragmentary elevation view of the rear spindle and associated components, with wire wrapped on the spindle.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 of the drawing is a broken view of a hanger wire or hanger 10 which is formed by the apparatus of this invention, and which is formed from an initially generally straight wire segment of selected length, with a pigtail being formed at one end consisting of a loop 12 and a return tail 13. The return tail is so named, since it returns in generally parallel relation with the straight portion of the segment referred to as the body 1 1.

FIG. 1 shows a hanger wire as initially supported by a concrete form 14, which is illustrated as a metal form for example, with the loop 12 being spaced from the upper surface of the form 14 by the return tail 13. The length of the return tail is selected to maintain the loop in spaced relation to the form, to assure that when the wet concrete I5 is poured it will fully envelope the loop 12 so that the hanger wire is securely retained within the concrete after it is set. While the illustrated loop consists of a single revolution, it may desirably have additional revolutions.

The hanger wire is of suitable gauge for its supporting function, and the forms 14 are provided with holes 16 of suitable diameter to permit ready insertion of the hanger wires and to permit ready removal of the forms after the concrete has set. The lengths of the hanger wires of course are selected for the particular application.

Referring now to the remaining figures, a preferred form of apparatus according to the invention includes a generally rectangular frame 20 to stand free in a shop area, and including a top panel which is principally a protective cover but which may be used as a convenient surface for supporting wire segments priorto forming the pigtails. FIG. 2 illustrates what is referred to as the front of the apparatus, while FIG. 4 illustrates the back.

As best shown in FIG. 3, a horizontal shaft 24 is rotatably supported in the frame having a front cylindrical mandrel 24F projecting from the front of the machine and a rear cylindrical mandrel 25R projecting from the rear thereof. The shaft is rotatably mounted in suitable bearings 26, and has non-rotatably fixed thereto a pinion 27 and an indexing ratchet cam 28.

As best seen in FIGS. 2 and 6, the pinion 27 is driven by means of a flywheel gear 30, fixed to a shaft 31 sup ported in a suitable bearing assembly on the frame 20. The flywheel gear carries a gear segment 32 adjacent to its periphery and axially spaced therefrom, and also carries a diametrically opposed counterweight 33. The gear segment 32 is disposed for intermittent driving engagement with the spindle pinion 27. The flywheel gear 30 is driven by means of a drive gear 34, non-rotatably fixed to a shaft 35 supported on the frame by a suitable bearing; and this shaft also carries large pulley 36. The pulley 36 is driven by an electric motor 37 carrying small pulley 38, through drive belt 39. The apparatus is provided with a suitable switch for selectively energizing the motor 37.

For providing lubrication for the gear segment 32 and pinion 27, a generally crescent-shaped oil pan 40 is disposed adjacent the lower periphery of the flywheel gear so that the gear segment may pass through oil contained in this oil pan.

The shaft assembly, which includes the mandrels 25, pinion 27 and index cam 28 is a low inertia assembly; and an index mechanism 43 including the cam 28 is provided to stop rotation of this assembly and to index the assembly in a preselected orientation after each drive by the gear segment. This index mechanism 43 is particularly illustrated in FIGS. 3 and 5. As best seen in FIG. the peripheral surface of the cam 28 is generally cylindrical and is provided with diametrically opposed index notches, to be engaged by an elongated reciprocating pawl 45 which reciprocates along an axis perpendicular to the axis of rotation of the shaft 24. The pawl includes a rectangular body provided with an inclined bearing face 46 at one end, and having a spring retaining finger 47 at its other end. The rectangular body is supported for reciprocation by hearing brackets 48, which prevent rotation of the pawl. As best seen in FIG. 3, a compression spring 49 is supported between the retaining finger 47 and a retainer assembly 50, secured on the apparatus frame 20 and including adjustment means for adjusting the compression of the spring 49. The cam notches, as illustrated in FIG. 5, include shoulders 53 disposed in generally radial planes at the leading sides of the notches relative to the direction of rotation, and by chordal bearing surfaces 54 generally perpendicular-to the shoulders 53. In operation, the cam is driven in the indicated direction ratcheting the pawl; and the drive ceases with the pawl bearing face 46 engaging a bearing surface 34. The pawl acts to stop rotation of the shaft assembly, and actually rotates the assembly in a reverse direction until the adjacent shoulder engages the pawl as shown in FIG. 5. The shaft assembly is then indexed in a preselected position.

The

mandrels

25F and 25R are provided with diametral slots 56, which extend from the ends thereof to a point adjacent the side walls of the frame 20. By way of example, the cylindrical mandrels may have an OD of 1 1/4 inches with the slots having a depth of 1 3/4 inches. As seen the drawings, the mandrel slots are always indexed in a horizontal plane by the index mechanism 43. In the preferred form of mechanism illustrated, the gear segment 32 is provided with one and one-half times the number of teeth provided on the pinion 27, so that the shaft assembly is rotated one and one-half revolutions for each drive engagement of the gear segment with the pinion. The number of revolutions may be greater, but should preferably be an odd multiple of half revolutions to produce a return tail 13 generally parallel with the body 11.

As best seen in FIGS. 3 and 8, a wire guide assembly at the front of the frame includes a bracket 58 mounted thereon defining a horizontal guide shelf, and an angle bracket 59 mounted on the guide shelf defines a vertical guide wall. The guide shelf 58 is disposed in a horizontal plane so that a wire segment guided thereacross will pass into and through the mandrel slot; and the guide wall 59 defines, with the guide shelf, a linear path for directing the wire 11 generally transverse to the mandrel axis but slightly angled relative thereto. Another element of the guide assembly is stop bracket 60 disposed at the opposite side of the mandrel which defines a limit for the feed of the wire through the slot. This stop bracket is adjustably mounted, since the position of the stop bracket determines the length of the return tail 13 illustrated in FIG. 1. FIG. 3 shows a wire segment against the stop bracket prior to drive of the shaft 24; and FIG. 7 illustrates the position of the hanger wire on the spindle just after completion of the drive cycle with the pigtail being formed as illustrated in FIG. 1. To maintain the wire segment generally in the line of feed during mandrel drive, a limit pin 61 mounted on the bracket 58 prevents the wire segment from swinging upward, as best seen in FIG. 8.

A guide assembly at the rear of the apparatus includes the same components namely a guide shelf 58, vertical guide wall 59, stop bracket 60 and stop pin 61. These guide assemblies are arranged sothat an operator feeding the front mandrel 25F would normally position itself at the left side of the apparatus, while an op erator feeding the rear mandrel 25R would position himself adjacent to the right side of the machine. This of course provides for maximum output, without the operators interfering with each other.

It will be apparent that the rear mandrel 25R will rotate in a counterclockwise direction, as viewed from the rear of the machine and illustrated in FIG. 9. As seen in FIG. 9 the rotation of the spindle will tend to swing the wire downward rather than upward; and the shelf 58 prevents swing in this direction. Because the rotation of the mandrel urges the wire segment 11 toward the shelf, the shelf 58 is provided with a rounded edge 58A to provide for smooth feeding of the wire to the mandrel.

To provide for the automatic removal of the hanger wires 10 from the mandrels after the pigtails are formed, identical stripper mechanisms are provided to coact with the mandrels. As best seen in FIGS. 2, 3, 6 and 7 the stripper mechanism for the front mandrel includes an elongated arm 64 pivotally mounted to the frame 20 at its lower end and defining a yoke 65 at its upper end receiving and extending around the mandrel. The normal position of the stripper arm is illustrated in solid lines in FIG. 6, and the arm is maintained in this position by a tension spring 66. As best seen in FIGS. 3 and 7, the yoke 65 is positioned adjacent to the proximal end of the mandrel, so that the pigtail is formed between the yoke and the distal end. The stripper arm 64 is moved to the strip position, illustrated in broken lines in FIG. 6, by means of a push rod 67 mounted for rectilinear movement in the apparatus frame 20, and actuated by cam 68 fixed to the face of the flywheel gear 30. At the selected time, the stripper arm swings in the manner indicated to strip the hanger wire from the mandrel.

The stripper mechanism for the rear mandrel 25R consists of the same components with the push rod 67a being necessarily longer as seen in FIG. 6. The timing of the stripper mechanism in relation to the shaft rotation is illustrated in FIG. 4, which shows clockwise rotation of the flywheel gear 30 with the gear segment 32 just releasing from the pinion 27 so that the mandrel is indexed in the position shown. As seen in this view, the push rod cam 68a is just approaching the push rod 67a, so that the hanger wire is stripped from the mandrel immediately following the indexing of the mandrel. It will also be seen from FIG. 4 that, following the return of the stripper arm by its associated return spring 66, the shaft 24 will not be driven again until the flywheel gear 30 has rotated approximately 180 degrees. The time interval for this half revolution of the flywheel gear allows time for the operator or operators to feed the next wire segment into the respective mandrel slots; and the speed of rotation of the flywheel gear is desirably selected to allow just sufficient time for the operator to discharge the finished hanger wire and to obtain and feed a succeeding wire segment into position, for most efficient operation of the apparatus.

Operation The operation of the apparatus, as apparent from the foregoing, involves the continuous drive of the flywheel gear at a relatively constant speed with accompanying intermittent drive of the mandrels at a speed selected for most efficient operation.

The wire segments to be operated on by the apparatus may be conveniently stacked on the top frame panel, in position to be readily grasped by either or both operators. After each drive of the mandrels, the operator feeds one end of a wire segment into and through a mandrel slot along the linear path generally defined by the intersection of the shelf 58 and guide wall 59, feeding the wire to the stop 60 which determines the length of the return tail 13. The operators hold the wires in this general orientation during the drive of the spindles; and during such drive the wire will be automatically withdrawn by the spindles, and it will be prevented from swinging either upward or downward by the respective pin 61 or shelf 58. Preferably the operator will continue to hold the wire segment during the pigtail forming operation, so that when the hanger wire is stripped from the spindle he may place it in a suitable container or on a suitable stack of hanger wires adjacent to his work station. Alternatively the operator may release his hold on the wire and allow the stripper mechanism to discharge the wire into an adjacent container for example.

Either simultaneously with the placing of the finished hanger wire in a suitable container, or immediately following, the operator will grasp a succeeding wire segment to be fed into the mandrel slot.

What has been described is a unique convenient and efficient apparatus which is readily available for use at any time for finishing the hanger wires, in the sense of forming the desired pigtails. The apparatus is convenient to use, providing for maximum output by either a single operator or by two operators to supply the demand at a particular time. That the machine is semiautomatic in operation, is a part of its inherent convenience providing for maximum output on demand with minimum fatigue on the part of the operators.

While the preferred embodiment of the invention has been illustrated and described, it will be understood by those skilled in the art that changes and modifications may be resorted to without departing from the spirit and scope of the invention.

What is claimed is:

1. Apparatus for producing hanger wires comprising a frame;

a rotatable shaft supported on said frame, having a cylindrical mandrel at one end provided with a diametral slot opening to its distal end; index means acting on said shaft for indexing said shaft, in the rest position, with the mandrel slot oriented in a preselected position; drive means for driving said shaft intermittently through selected numbers of revolutions;

guide means on said frame for guiding an elongated wire segment longitudinally into said mandrel slot transversely of said mandrel; stop means on said frame for limiting the longitudinal movement of said wire segment beyond said mandrel slot;

stripper means for stripping the hanger wire axially from said mandrel; and actuator means for effecting operation of said stripper means by said shaft drive means in timed relation with the intermittent drive of said shaft.

2. Apparatus as set forth in claim 1 said shaft drive means including a pinion fixed to said shaft, and a rotatable flywheel carrying a gear segment for intermittent engagement with said shaft pinion.

3. Apparatus as set forth in claim 2 an oil reservoir disposed adjacent to the lower portion of said flywheel, configured to receive a portion of said gear segment to apply lubricant thereto.

4. Apparatus as set forth in claim 1 said gear segment and said pinion having a coacting number of teeth for driving said shaft through at least one full revolution and one additional half revolution for each engagement thereof, thereby producing a pigtail consisting of at least one full loop, and a return tail projecting from said loop in generally parallel relation to the hanger body.

5. Apparatus as set forth in claim 4 said shaft and mandrel being disposed in a horizontal plane; said index means acting to index said mandrel slot in said horizontal plane;

said guide means comprising intersecting horizontal and vertical walls, with the intersection of said walls being disposed generally in said horizontal plane;

and said stop means being adjustable relative to said shaft axis to determine the length of said return tail projecting from said loop.

6. Apparatus as set forth in claim 5 including means for maintaining said wire segment generally in said horizontal plane during the drive of said mandrel. 7. Apparatus as set forth in claim 1 said index means comprising a disk-like ratchet cam fixed to said shaft and a spring loaded pawl urged into engagement with the peripheral surface; said pawl being disposed to reciprocate in the plane of the shaft axis perpendicular to said axis; said cam having diametrically opposed notches each consisting of a shoulder disposed in a generally radial plane at the leading side thereof, relative to the direction of drive, and a bearing surface disposed in a plane generally perpendicular to said shoulder plane, whereby said pawl acting on said bearing surface urges rotation of said cam in a direction to engage said cam shoulder with said pawl; and said shaft and associated structure having low inertia, thereby allowing said pawl to stop rotation of said cam and shaft.

8. Apparatus as set forth in claim 1 said stripper means comprising an elongated arm having a yoke at one end receiving said mandrel, and being hinged to said frame at the other end; actuator means for intermittently swinging said yoke arm along said mandrel. including cam means mounted on said flywheel and reciprocable connecton rod means coupling said yoke arm and said cam means.

9. Apparatus as set forth in claim 1 said rotatable shaft having a second cylindrical mandrel at its other end provided with a diametral slot opening to its distal end, with the diametral slots of the two mandrels being disposed in a generally common plane; and corresponding said guide means, said stop means, said stripper means, and said stripper actuated means coacting with said second mandrel.

Claims

1. Apparatus for producing hanger wires comprising a frame; a rotatable shaft supported on said frame, having a cylindrical mandrel at one end provided with a diametral slot opening to its distal end; index means acting on said shaft for indexing said shaft, in the rest position, with the mandrel slot oriented in a preselected position; drive means for driving said shaft intermittently through selected numbers of revolutions; guide means on said frame for guiding an elongated wire segment longitudinally into said mandrel slot transversely of said mandrel; stop means on said frame for limiting the longitudinal movement of said wire segment beyond said mandrel slot; stripper means for stripping the hanger wire axially from said mandrel; and actuator means for effecting operation of said stripper means by said shaft drive means in timed relation with the intermittent drive of said shaft.

5. Apparatus as set forth in claim 4 said shaft and mandrel being disposed in a horizontal plane; said index means acting to index said mandrel slot in said horizontal plane; said guide means comprising intersecting horizontal and vertical walls, with the intersection of said walls being disposed generally in said horizontal plane; and said stop means being adjustable relative to said shaft axis to determine the length of said return tail projecting from said loop.

6. Apparatus as set forth in claim 5 including means for maintaining said wire segment generally in said horizontal plane during the drive of said mandrel.

7. Apparatus as set forth in claim 1 said index means comprising a disk-like ratchet cam fixed to said shaft and a spring loaded pawl urged into engagement with the peripheral surface; said pawl being disposed to reciprocate in the plane of the shaft axis perpendicular to said axis; said cam having diametrically opposed notches each consisting of a shoulder disposed in a generally radial plane at the leading side thereof, relative to the direction of drive, and a bearing surface disposed in a plane generally perpendicular to said shoulder plane, whereby said pawl acting on said bearing surface urges rotation of said cam in a direction to engage said cam shoulder with said pawl; and said shaft and associated structure having low inertia, thereby allowing said pawl to stop rotation of said cam and shaft.

8. Apparatus as set forth in claim 1 said stripper means comprising an elongated arm having a yoke at one end receiving said mandrel, and being hinged to said frame at the other end; actuator means for intermittently swinging said yoke arm along said mandrel including cam means mounted on said flywheel and reciprocable connecton rod means coupling said yoke arm and said cam means.