US3895659A

US3895659A - Apparatus and method for forming circular dynamoelectric machine field windings by pushing

Info

Publication number: US3895659A
Application number: US473679A
Authority: US
Inventors: Patrick L Grawcock
Original assignee: Essex International Inc
Current assignee: Essex International Inc
Priority date: 1973-05-30
Filing date: 1974-05-28
Publication date: 1975-07-22
Anticipated expiration: 1992-07-22
Also published as: CA1017542A; FR2232103A1; SE400677B; GB1462283A; IT1017637B; JPS5031381A; SE7407159L; DE2425576A1

Abstract

An apparatus and method for placing magnet wire in slots respectively defined by the blades of coil insertion apparatus which lie on an imaginary cylinder thereby to form a circular dynamoelectric machine field winding. The wire is pushed and simultaneously guided in a circular path which overlaps the cylindrical array of blades and which is aligned with the open ends of two of the slots whereby the wire is pushed into the two slots.

Description

United States Patent 1 Fidiam [54] WIRE HANDLING AND MANIPULATING APPARATUS [76] Inventor: John F. Fidiam. 13133 Madonna Lane. Fairfax. Va. 22030 [221 Filed: May 30.1973

[21] Appl. No.: 365.284

[52] US. Cl 140/93 R. 29/203 MW [51] Int. Cl ..B2lf 15/00 [58] Field of Search ..140/93; 29/203; 242/717.

[56] References Cited UNITED STATES PATENTS 2.696.656 12/1954 Madden 140/93 2.818.756 1/1958 Moeller 8l9.5l

3.117.736 1/1964 Loy, et al 242/7.l7

3.435.858 4/1969 Taysom. et al 140/93 3.516.140 6/1970 Bohannon 29/203 3.530.746 9/1970 Gudmestad S19.51

3.006.563 10/1971 B05. ct al 242/717 3.774.283 l1/1973 Staiger 29/203 Primary Examiner- Lowell A. Larson Attorney, Agent, or FirmMillen, Raptes & White l ABSTRACT Two embodiments of an apparatus for preparing and wrapping stripped ends of wire especially on electrical terminals for interconnecting the terminals are disclosed. An X. Y locator is used to shift and accurately position the wire wrapping head of the apparatus. The head includes a wrapping tool to which wire of an indeterminate length is fed. cut, stripped and loaded in a unique. fully automatic manner at the first end. and then the procedure is repeated at the second end. Additional wires are automatically connected in accordance with data supplied to the X. Y locator. Gripper means positively hold the wire adjacent the 1 3,895,659 l l July 22, 1975 tool and the tool is advanced and retracted from each terminal on a sliding carriage. The wrapping tool includes a non-rotatable bit element having a slanted. open notch on the side for efficient side loading and a rotatable elongated concentric sleeve. The sleeve has a bisected slot for loading of the stripped end in a closed groove portion thereof and through an open groove portion and the notch. The loading operation is performed by relative shifting ofthe sleeve and only after the end has been cut and stripped to prevent fracture of the wire. A feed tube shifts the wire to a position between a movable door and backup assembly that carries blades and forms the stripping and cutting means and then through a cam-shaped clamp means to positively control the end of the wire: the clamp being made more effective upon movement of the wire in a second direction and into a U-loop that is caught by catch means on the side of the cam. An anti-backforce mechanism is provided by a second sliding carriage with a biasing means connected be tween the same and the base member that is carried by the locator means. This mechanism is operative at least during advancement of the tool to the terminals to prevent damage to terminals should misalignment occur. Control means between the sliding support of the loading means and the support for the main frame or sliding carriage assures proper loading and full advancement and retraction of the tool. An air turbine motor preferably rotates only the sleeve for the wrapping operation and indexing ofthe sleeve is performed while single direction rotation is main tained. Holder means guides the second end of the wire for proper reception by the gripper means. All of the above structure is present in both embodiments of the invention. it being understood that the difference lies in specific structural details. as will appear below.

47 Claims. 13 Drawing Figures 10 n a w 9?. so l5 1 11 J 9| If 15 a 14 PATENTED JUL 2 2 ms CONT SZOL Loeuc PATENTED L I915 3,895,659

' SHEET 2 we. 55 PRESSURE MOTO R.

Am 60 51 SUPPLY 6'5 \.0\N 64 rzzssu RE ll! 15 F/G. 2

PATENTED JUL 2 2 I915 PATENTED JUL 2 2 ms SHEET PATENTED JUL 2 2 SHEET WIRE HANDLING AND MANIPULATING APPARATUS The present invention relates generally to the art of handling and manipulating wire to make electrical interconnections. and more particularly, to an improved apparatus for automatically cutting and stripping in sequence two ends of a wire from a supply of indeterminate length and wrapping or affixing the prepared ends to separate electrical terminals.

BACKGROUND OF THE INVENTION Solderless wrapped connections on airline type wiring between electrical terminals have become standard for wiring computers, television, communications equipment and similar electronic gear. In a typical manufacturing process where two electrical terminals are to be connected, a length of wire is pre-measured and pre-stripped at both ends and one end of the wire is inserted at a time into a special tool, the tool is placed on the terminal post and the bare wire is coiled tightly around the post by rotary action of the tool. This wrapping process is repeated for the second end of the wire after extending the wire to the second terminal thereby creating an elec trical interconnection. Wrapped connections have demonstrable advantages, such as: (l) shorter elapsed time for making a connection; (2) no additional parts required; (3) high shearing force at the corners of the terminal to assure clean metal-to-metal contact and sealing of the contact area from ambient conditions; (4) greater mechanical attaching stability on the terminal so that assembly and handling operations and vibrations do not cause loosening of the wire; and (5) wider clearance between the adjacent terminals so that a larger number of connections per unit area can be realized.

As the technology of computers has increased and integrated circuits have brought about a reduction in the hardware size, the pressure has increased considerably for making the terminal boards that support the circuits smaller. As mentioned above, the wrapped connection is best suited of all of the known ways of making a high quality connection, but the smaller spacing and the greater number of wires flying over the terminal board has made it increasingly difficult to economically provide the necessary interconnections.

To alleviate the problem, machines have been introduced in recent years that are known in the art as semi-automatic wiring machines. These machines are in reality merely position locators that sequentially identify for the wire wrapping technician the terminals that are to be interconnected. Such a machine typically provides a mounting for the terminal board and adjacent the board an X. Y locator with pointer which moves in response to data from a precoded punched or magnetic tape. When the end of a pointer stops, it is in alignment with the terminal that is to be wrapped and the operator then manually inserts the stripped end of the wire into the hand-held tool, engages the terminal with the tool and activates the tool to wrap the wire. The locator is then programmed upon receiving a signal from the operator to go to the next terminal to be connected and the manual wrapping process is repeated. These machines have increased the production dramatically to approximately 500 terminations per hour. and thus are in widespread use, especially among small to medium size computer manufacturers and users. However. as the uses and complexity of computers continues to accelerate. still more economical and mistake-proof means for performing the wire wrap operation. especially for the small and medium size users is needed.

To our knowledge. there has not been any successful solution to the problem of fully automating the wire wrapping procedure for the small to medium size operations that have in the past used the semiautomatic wiring machine. On the other hand. for the large scale user and equipment manufacturers. machines have been proposed to fully automate the wire wrapping procedure. Representative of the efforts in this area are the machines disclosed in the patent to Madden 2.696.656. issued December 14. l954. and the patent to Bos et al. 3.103.735. issued September 17. 1963.

In the Madden patent. the principle of automatic wire feeding and wrapping is taught: however. as can be seen from the disclosure. the tool is relatively complex. and most importantly, it is incapable of making wrapped connections on closely spaced ter minal posts found in a computer installation. The machine represented by the Bos et al patent is even more complex and expensive. requires a large area that makes it unsuitable for operations where floor space is at a premium. has proven to be incapable of effective monitoring and control by an operator. and is even unsafe in an emergency. Furthermore. the machine requires two separate wrapping heads for making the two wrapped connections of one wire and a highly complex logic system for determining the length of the wire and the proper spaced location of the two heads. Thus. a machine made in accordance with the teaching of Bos et al.. or Madden. not only limits the market to which automatic wire wrapping machines can be supplied. i.e.. to the few relatively large users and hardware manufacturers. but also these machines have certain inherent shortcomings in terms of efficiency of operation.

OBJECTIVES OF THE INVENTION Accordingly. it is an object ofthe present invention to provide a simplified and low cost apparatus for automatically performing the wire wrapping operation on computer terminal boards or the like.

It is another object of the present invention to provide a machine that is not only low cost and fully automatic. but which also has the capability of working on closely spaced terminals and that may be monitored and controlled in a safe manner by an operator in an emergency situation.

It is still another object of the present invention to provide an improved wire wrapping apparatus. and subcombinations thereof. that is specially designed for use in conjunction with a conventional position locator, thereby giving many small and medium size users capability of conversion from semi-automatic to automatic wire wrapping.

It is still another object of the present invention to provide a wire wrapping head of simplified and lightweight design and with superior mechanical features to handle and manipulate the wire while maintaining the same under positive control at all times.

BRIEF DESCRIPTION OF THE INVENTION A wire wrapping apparatus and subcombinations thereof constructed in accordance with the principles of the present invention comprises a rotary wrapping tool for wrapping the stripped and cut ends of a wire on spaced terminals to form an interconnection of high integrity. means for catching and loading the wire on the tool. stripping and cutting means for forming the connector ends. and means for advancing and retracting the tool along the Z axis ofthe tool toward the terminal in a rapid. but delicate manner. In the overall combination invention. these components. which collectively form a wire wrapping head. are coupled with locator means for traversing the tool to new X. Y locations for each new first and second end wrapping.

In accordance with one specific aspect of the present invention. a gripper means is provided adjacent the tool to positively hold the wire while stripping the ends and loading into the tool. And. a lower clamp is provided adjacent the cutting means to further provide additional positive holding ofthe wire through a U-shaped loop of wire that assures continued operation without interruption. The entire handling and manipulation means for the wire with the positive control is furthermore advantageously designed so that a single tool with minimal frontal area is operative to position and wrap both ends of the wire.

The wrapping tool is in and of itself important to the invention in that it allows convenient side loading of the prepared end. A sleeve that is concentric with the bit element is mounted for relative rotation therewith. The sleeve is provided with a longitudinally extending slot bisected by the bit element to form an open groove and a closed groove contiguous with the bit element. Upon relative axial shifting between the sleeve and the bit element the wire is loaded into the closed groove by passing through the open groove and the notch. The wire is loaded in the tool by means separate from the cutting and stripping means so that fracture of the wire due to excessive tension is avoided.

The stripping and cutting subcombination includes a movable door and backup assembly that mounts the opposed stripping blades and the cutter blade for simultaneous operative movement. The assembly is mounted on slide means that moves toward the end of the wire only after the cutting and the score for the stripped insulation has been completed.

The lower clamp for positive control is positioned below the cutting blade and includes. more particularly. a pivotal cam element having an operative gripping surface and an opposed jaw forming a nip to trap the wire. The cam element is pivoted to open to receive the wire automatically as the same is pulled in the first direction therethrough. and catch means on the side of the cam element actually increases the clamping action when the wire is pulled in the opposite or second direction. In one embodiment a V- shaped catch is employed on the side of the cam element to positively trap the wire. The U-shaped loop formed by the cam element in either embodiment plays an important role in assuring positive control of the wire at all times. as mentioned above.

The feeding means subcombination includes a feed tube carrying the wire that is mounted substantially normal to the tool rather than in the same direction thereof so that the tube does not require advancement with the tool to the terminal board where interference with the terminals could occur. as in prior art machines. such as shown in the Madden patent. Means is provided for shifting the feed tube to provide a new length of wire through the stripping and cutting means and for engagement with the lower clamp. The tube is mounted for pivotal action to permit glancing movement past the gripper means that serves to catch the wire and hold the same in position for receipt in the side loading notch of the bit element. in one embodiment. the gripper means plays an important role of further assuring continued positive holding of the wire so that the same does not escape during the critical loading operation in the tool. The gripper in this embodiment includes two elongated jaws. one stationary and one movable. that can move forward with the sleeve on the loading operation and. if desired. for the wire wrapping operation. The ends of the gripper jaws are narrow so as to be easily accommodated between adjacent rows of the terminal posts on the terminal board and serve to tuck in previously attached wires. However. since the entire wire end is held firmly in the closed groove of the tool after loading. the gripper means need not be advanced at all or advanced all the way to the terminal board for a successful wrapping operation.

In fact. in a second embodiment illustrated. the gripper means remains stationary and a separate pusher means serves to carry forward the wire adjacent the wrapped end and tuck the same between the terminals. The stripped wire end in both embodiments is advantageously carried totally within the tool after loading so that it does not stick out the side of the tool where it could fly around out of control during the tool rotation.

A motor means. such as a pneumatic cylinder. is connected to a sliding support in order to perform the loading operation through relative movement of the sleeve and the bit element. This motor is carried by a mounting assembly to provide a reaction point for movement of said support. and the main frame of the head forms a first sliding carriage on the assembly also responsive to said motor means. With this configuration in the first embodiment. the motor means thus serves the function of not only loading the wire in the tool. but also of bringing the tool by movement of the main frame into engagement with terminals. In the second embodiment. a separate motor may be employed for the latter function. The mounting assembly forms a second sliding carriage on a base member (that is in turn carried by the X. Y locator means). thereby providing an additional relative motion interface. Biasing means is connected in accordance with the invention between the mount ing assembly and the base member to provide an anti-backforce mechanism which automatically produces the proper wrap tightness on the terminal post. The additional movement and biasing interface also serves to limit the forward force of the tool to prevent bending of a misaligned terminal. When a bent terminal pin or post is encountered. the operator. who may have responsibility for several automatic wire wrapping machines designed in accordance with the present invention. simply manually retracts the wire wrapping head against the force of the spring. straightens the terminal and releases the head. whereupon the post is properly engaged by the tool and the wrapping proceeds without further interruption or down-time of the machine.

As an added feature in the second embodiment illustrated in this application, the biasing means may be mounted for retraction from second carriage engagement as the wrapping operation is initiated. In this instance. only the friction between the parts controls the backforce for wrapping. which condition is preferred under certain circumstances. such as where relatively light gauge wire is used.

An operational feature in the first embodiment includes the use of a novel latch means and differential friction between the sliding support and the mounting assembly to assure full and proper sequential advancement and retraction of all parts. Of course. in the second embodiment. where a separate cylinder is employed. no such latch means is required. The sleeve for performing the wrapping of the wire is indexed by a rotating arm engaging a stop means during the retraction movement of the tool. The indexing can in accordance with the invention take place while the sleeve continues to rotate in the same direction as the wrapping. The indexing is performed and maintained by a secondary and lower pressure on the air turbine drive motor. If the friction in the tool is insufficient to hold the tool against rotation after the wire is loaded, the lower pressure may be terminated as the tool starts to move forward so that the proper position is held until wrapping is initiated. A holder means captures the wire when the head is moved to the second location in order to position the wire for catching by the gripper means to assure proper formation of the second stripped end. In the first embodiment. control of the wire during the stripping and cutting operation is further assured by using a single motor that closes the door prior to any move ment of the slide means and by providing angled projections on the stripping blades that form intersecting Vs to enclose the wire prior to the cutoff by the knife. Separate motors for the door and the slide means are contemplated in the second embodiment.

Within certain broader aspects of the present invention, it is contemplated that the wire handling and manipulating subcombinations of both embodiments have utility for making electrical interconnections where the end of the wire is affixed to the terminal without wrapping such as by a chemical bonding process. Of course, the side loading wire wrapping tool subcombination can be used in other semi-automatic or automatic wire wrapping environments. The pivotal clamp that is self-loading and capable of providing increased holding force when a wire loaded therein is pulled in a second direction can be utilized in analogous manufacturing processes where control of a piece of wire is necessary. One such application would be in the making of wire harnesses on ajig board with the pivotal clamps serving to locate the ends of the wires for convenient attachment of whatever connector is desired.

Still other objects and advantages of the present invention will become readily apparent to those skilled in this art from the following detailed description. wherein we have shown and described only the two preferred embodiments of the invention. simply by way of illustration of the best modes contemplated by us of carrying out our invention. The first embodiment illustrated is preferred for its simplicity of structure. and thus lower initial cost. and for its advantages in terms of combining functions for rapid and assured sequential operation. The second embodiment is preferred for its reliability of operation at the present time. This reliability results mainly from separate mechanical mechanisms and operators for performing each of the several functions in the wrapping operation. as well as different designs and configurations of the parts and elements. As will be realized. the invention is capable of still other and different embodiments. and its several details are capable of modification in various obvious respects. all without departing from the invention. Accordingly. the drawings (FIGS. l-l4. first embodiment. and FIGS. l5-l7. second embodiment). and the description of the two embodiments. are to be regarded as illustrative in nature. and not as restrictive. Unless otherwise clear from the language therein. the invention is to be interpreted in all instances as broad enough to cover both embodiments illustrated. as well as all equivalent embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall perspective view of a wire wrap head and base assembly constructed in accordance with the teachings of the present invention;

FIG. 2 is a perspective view ofthe wire wrap head and base assembly of the invention showing the side opposite of that shown in FIG. 1;

FIG. 3 is a section view taken through the wire wrap head of FIGS. and 2 showing portions of the wire feeding, catching and loading. and stripping and cutting mechanisms of the present invention;

FIG. 3A is a showing like that of FIG. 3 but with the parts in a different sequence step;

FIG. 4 is a plan view of a wire wrapping head mounted on an X. Y locator forming the combination inventive concept of the present invention;

FIG. 5 is a schematic diagram of the control system and actuators of the invention;

FIG. 6 is a side view of a portion of the wire wrapping head;

FIG. 7 is a top plan view of the head constructed in accordance with the principles of the present invention. and showing the gripper means and its relationship with the wrapping tool. and the indexing means. in more detail:

FIG. 7A is a top plan VIEW like FIG. 1 showing the indexing means at a different sequence step:

FIGS. 8, 9-9A. and 10-10A show in sequence the catching and loading operations of the apparatus of the present invention;

FIG. 11 is an enlarged detail and cross-sectional view of the wire wrapping tool with a stripped wire in a fully loaded position in readiness to perform a modified wrap on a terminal post:

FIGS. 12 and 13 show the supporting base assembly including the anti-backforce arrangement. with positioning of the latch means in sequence for loading and then for forward advancing movement for wrapping: and

FIG. I4 is a final sequence showing positioning and holding of the wire in readiness for forming the second stripped end.

FIGS. l-l4 thus in composite. show the first embodiment of the invention. and the second embodiment is shown in FIGS. 15-17. described below.

FIG. 15 is a top plan view of the wire wrap head and base assembly of the second embodiment of the invention:

FIG. 15a is a section view taken along line 15A- ISA of FIG. 15 showing the clamp element that forms the U-shaped loop to control the free end ofthe wire:

FIG. 16 is a transverse section view taken through the assembly of FIG. 15 along line 16-16 showing portions of the wire feeding. catching and loading. and stripping and cutting mechanisms of the present invention;

FIG. [7 is a longitudinal side section view taken through the assembly of FIG. 15 along line 17-17 showing substantially all the remaining parts of the basic structure of the second embodiment; and

FIG. 18 is a section view like FIG. 17 showing the parts in a different position with the wire end stripped and the holder pin withdrawn.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT With reference now to FIGS. l-3 of the drawings. there is disclosed therein a wire wrapping head embodying the several features of the first embodiment of the present invention. In general terms. the wire wrapping head 10 comprises a main frame ll that houses a wire catching and loading means. generally designated by the reference numeral I2. stripping and cutting means 13 and head advancing and retracting means I4. A rotary wire wrapping tool is provided on a sliding support 1511 on the upper portion of the head ll) injuxtaposition with the catching and loading means I2. As best shown in FIG. 3. a wire W may be fed from a suitable location adjacent the head 10 from reel R containing wire of indeterminate length. The wire W is fed through a bodily movable feed tube I6 extending normal to the tool I5. said tube [6 having an outlet orifice 17 positioned just above the end of said tool 15. The wire W is adapted when extending downwardly past the tool 15 (see FIG. 1. for example) to be in cross engagement therewith. and is held in this position by a pair of opposed gripper jaws I8, 19 forming an important part of the catching and loading means 12.

The feed tube 16 is carried by a support block 20 pivotally mounted on the piston rod 21 of a suitable air cylinder 22. The piston may be double acting or spring biased to raise the tube 16 to its uppermost position. as shown in FIGS. 3 and 3A. Upon actuation of the cylinder 22. the feed tube is pushed down to the dotted line position shown in FIG. 3. This downward movement when initializing wire portion W. of the wire is held up serves to feed an initial length of wire into the lowered dotted line position shown. When the wire W is thus positioned it extends through the stripping and cutting mechanism 13 and an initial cut is made by the knife. as will be seen below. This positioning and cutting of the wire W is known as the "initializing" process and is the only step required to completely set the head 10 in readiness for operation and needs to be performed only when the roll R of wire W is to be replenished.

The stripping and cutting means 13 includes a pivotal door 25. on the top of which is mounted a stripping blade 26 and on the bottom of which is mounted a knife or cutting blade 27 (see FIG. 1). The door is supported on a backup member and slide means 28 that carries an opposed stripping blade 29 and an opposing slot for the knife 27. The

blades

26, 29 have dual projections forming opposed Vs serving to locate and capture the wire W as it moves through the mechanism. as shown by the dotted lines in FIG. 3. These projections are designated by reference numeral 260 in FIG. 3.

0n the lower portion of the slide means 28 there is mounted a lower cam-shaped clamp 30. that is pivotally mounted and spring biased in the counterclockwise direction. as viewed in FIG. 1. This clamp catches and traps the wire W as the outlet end 17 of the feed tube 16 moves down to its lowermost position and through the nip. The clamp 30 holds that portion ofthe wire that is to become the U-shaped control loop. as will be apparent shortly.

The door 25 is spring biased to open to the position shown in FIGS. land 2. A lower corner ofthe door 25 is provided with a cam surface that is operative to be engaged by a pivotal actuating cam 36 mounted on the slide means 28. The upper face of the cam 36 is positioned for engagement by a downwardly moving piston rod 37 of a second pneumatic cylinder 38. Slide means 28 is constantly urged in the upper direction by compression spring 39. It will be realized that the single cylinder 38 is operative to first close the pivotal door 25 through the action of the cam 36, and thereafter (when the cam 36 can pivot no farther because the door has reached its fully closed position) to start the slide means 28 travelling in the downward direction. It is important to note that the opposed projections [611 have captured the wire. The opposing sharpened portions with the Vs score the insulation in a line around the wire W. and at a point below. the knife 27 has cut the wire. thus forming the end thereof.

As the slide means 28 moves toward its final downward position. the initial operative end is held in the lower clamp 30. Since the wire is freely movable through the feed tube 16. a brief retro movement of the wire W may take place and is taken up by any suitable slack means (not shown). It is also understood that the roll R is mounted on any suitable arbor or cradle and may be regulated by suitable brake means (not shown) to prevent overrunning. When the slide means 28 has reached its final lowered position (see. for example. FIG. 9) the initializing wire portion W. is removed and may be discarded whereupon the machine is ready to commence making wrapped interconnections between terminals.

The head 10. whose major functions have thus far been broadly described. is mounted on a suitable locator means. generally designated by the reference numeral 40 in FIG. 4. The locator may be merely a semi-automatic wiring machine presently sold on the commercial market by several companies. such as Standard Logic. Inc. of Santa Ana. California 92707. The specific locator shown in the present preferred embodiment can be readily related to the Standard Logic, Model No. WWM-SOO that employs crossed lead screws 41. 42 on slidable supports carried by a rectangular frame 43. The usual pointer of the locator 40 has been converted to a travelling slide carrier 44.

The wire wrapping head has. as is shown in FIGS. 1 and 2. a base assembly 45 and this assembly is mounted directly to a base plate 46 carried by the locator slide carrier 44. With this mounting. it is clear that the head 10 is capable of movement in the X direction. as denoted by the double ended arrow at. and in the Y direction. as indicated by the double ended arrow ri in order to be positioned over any selected terminal 2 on terminal board B. As is well known in the art.

motors

47, 48 activate the

screws

41, 42, respectively in accordance with control logic means 49 that may be responsive to either punch tape. magnetic record or otherwise controlled.

A significant aspect of the inventive concept of the present invention is to provide a wire wrapping head 10 that is of a simple and lightweight design so as to be adapted to be carried on a conventional X, Y locator. such as the Standard Logic locator 40 shown. This successful design and novel combination of mechanisms of this first embodiment of the present invention gives results not heretofore obtained. In essence. a low cost. and yet fully automatic and dependable wire wrapping apparatus has been realized. Small and medium size firms can now afford automatic wire wrapping machines. and semi-automatic machines may be easily converted. It should however be clearly understood that the specific type of X. Y locator is of no particular patentable moment. and that therefore, the wire wrapping head 10 of the present invention can be used with any number of others. such as the type of locating device shown in the Bos et al Patent 3,103,735. cited above, without departing from the principles of the invention.

An important factor in designing a wire wrapping head 10 capable of being successfully carried and positioned on the X, Y locator 40 in both of the embodiments of the invention was found to be the simplicity of construction and design of the movable parts and the actuators for controlling the same. In addition to the

pneumatic cylinders

22 and 38 described above, in the specific first embodiment there is required only two additional linear actuators; a pneumatic cylinder 50 that is operative to close the

gripper jaws

18, 19 and a main cylinder 51 for loading the wire in the tool and thereafter advancing the main frame 11 to bring the tool 15 in engagement with the terminals t. A single air turbine motor 52 is provided to drive the wrapping tool 15 and is carried by the sliding support 15a. A general view of the placement of these motors may be seen in FIGS. 1 and 2 of the drawings.

In FIG. 5, a complete schematic of the operating controls for these actuators has been illustrated. Here. it can be seen that each of the

pneumatic cylinders

22, 38, 50 and 51 may be connected through control lines to a simple fluidic control circuit 55 for actuation in proper sequence. Although a fluidic control system (that is. utilizing pure fluid elements and switches). is desired for proper actuation of the cylinders because of its lightweightness. simplicity of design and low cost. it is obvious that electronic controls. including electrically operated switches and valves. could also be utilized to operate the components in proper sequence. Since the particular configuration of the control circuit is of no import to the present invention. no further showing is deemed necessary. The typical system. such as shown in the 805 et al Patent 3.l03.735. could be easily adapted by one skilled in the art in order to practice the present invention.

The control circuit 55 also may be provided with an additional air pressure line 56 that may be connected to a suitable inlet 57 (see FIG. 2) on the back of the pivotal door 25. A passageway in the door opens on the interior side. and when a pulse of air is provided through the line 56. the stripped length of insulation left by the previous stripping cycle will be dislodged and blown free.

The control circuit 55 may be provided with the necessary compressed air from a conventional compressor 60 through a high pressure trunk passageway 61. The motor 52 is provided with its high pressure driving air through a servo valve 62 operated by said control circuit 55 and a shuttle valve 63. The shuttle valve 63 also has constant low pressure supplied through input passageway 64. As will be evident. when the valve 62 is deactivated (not providing high pressure air via the passage 61). the low pressure air 64 shifts the shuttle ball 65 to the position shown. so that the turbine 52 is driven constantly forward in a standby condition at low power. When the valve 62 is opened by command from the circuit 55. the high pressure air biases the ball 65 to the right in FIG. 5. and the turbine is immediately operated on high pressure. The high pressure mode is utilized for the power or wrapping cycle and the low pressure mode is utilized for indexing as will be further explained. Typically. the high pressure air may be supplied at 80 pounds per square inch and the low pressure air regulated to approximately 5 pounds per square inch.

As shown in FIG. 6. the air turbine 52 drives the tool 15 through suitable gears 70. 71. Tool 15 is supported by suitable bearings in the sliding support 1511 and may be easily removed for replacement. as is necessary from time to time due to wear.

As shown in FIG. 7. the gripper jaws l8. 19 are elongated and extend substantially parallel with the tool 15. The jaw 19 is slightly offset to the left (in this figure). so that the wire adjacent the stripped end held by gripper avoids interfering with the adjacent terminal when the tool 15 has moved to the full in" position (FIG. 11). The movable jaw l8is carried by the stationary jaw 19 by suitable parallel links 72. 73. thus providing for parallelogram type movement of said jaw 18. This movement is generated by an operator cam 74 mounted on the movable jaw 18 and positioned for engagement by the push rod 75 of the actuator cylinder 50. The parallelogram type linkage assures a strong sidewise component to make certain of secure gripping action of the wire at the operative portions of the jaw l8. 19 adjacent the ends or tips (see FIG. 3). The slanted engaging surface 76 further assures a positive sidewise gripping force and secure locking of the jaws l8, 19 together under continued actuator force. A return spring 77 is provided to open the jaws l8. 19 at the appropriate time in the cycle when the cylinder is deactivated.

To perform the rotary indexing function on the tool 15. the upper or driven gear 71 has a radially extending indexing arm 80 engaging a stop finger 81 when the sliding support a is in the retracted position (FIG. 7). The arm 80 moves free of engagement when the support 151: has advanced beyond the extent of the stop (FIG. 7A). With reference back to FIG. 5, the valve 62 is opened only after the stop 8] has been disengaged and full power is applied to the tool through the shuttle valve 63 for the wrapping operation. When the support 15a is again retracted. the low pressure is again applied and the stop 81 is engaged automatically thereby stopping and then retaining the tool in the proper orientation for the next loading operation. With this arrangement, it will be realized that indexing is simply yet positively accomplished at just the right time during the cycle and without the need for troublesome reversing ofthe tool as required in prior art arrangements.

After the initializing operation. that has been explained in conjunction with FIG. 3 takes place. the feeding cylinder 22 is presently to be deactivated so as to raise the feed tube 16 to its uppermost position. as best shown in FIG. 8. It will be remembered that at this point the grippers l8. l9 are open in anticipation of receiving the wire W and also the stripping and cutting door is open for the positioning of the wire that is to occur. It should also be noted with respect to the showing in FIG. 8 that the pivoting action ofthe feed tube 16 allows the outlet end 17 to glance past the stationary gripper 19 to prevent damage to the parts and so that in the final catching position the wire W is held firmly against said gripper 19 and the tool IS. The pivoting action also assures favorable glancing action through the lower clamp 30.

The value of the lower clamp can be further identified in the showing of FIG. 8. Here. the wire terminal portion W: has been formed by the initializing cutoff and by movement of the feed tube 16 in the opposite or the second direction a U-shaped loop has been formed about a V-shaped catch formed by a pin 85 extending from the side of the clamp 30. The outer insulation of the wire is wedged and caught in the V. This assures that the clamp 30 is tended to be further rotated in the clockwise direction. This action. in turn. tends to rotate the cam 30 so as to assure that inner gripping surface 86 is clamped even harder against the wire terminal portion W held against opposed jaw member 87. and thus. positive control of the wire terminal portion W is advantageously gained. This U-shaped loop is important to the operation of the present invention in that it alleviates the problem of the wire end possibly flying loose. as can occur in other clamping arrangements.

Reverting momentarily to FIG. 3. it will be remembered that the tool 15 is positioned directly below the outlet orifice 17 of the feed tube 16. At the upper end of the stroke. a stop 90 is positioned to hit the inlet end of the tube 16 and thus pivot the outlet end 17 higher than would normally occur and thereby slightly increase the stroke. Also. the stop 90 can serve as a means for locking the end 17 of the tube 16 in the exact position to insure catching of the wire W on the tool 15. Similarly. when the feed tube 16 reaches its dotted line position below. stop 91 serves to pivot the same to increase the stroke and to lock the tube 16 in position. In this manner. the precise feeding ofthe wire W and the locking in the upper and lower positions is ensured.

The next step of the sequence is shown in FIG. 9 and 9A. Here the

gripper jaws

18, 19 have captured and are holding the wire just below the outlet end 17 of the feed tube 16. Immediately thereafter. the cutter and stripper cylinder 38 is activated to first close the door 25 and trap the wire between the projections 260. on the

blades

26, 29, score the wire by the interaction of said stripping

blades

26, 29, and cut the wire by the knife 27 spaced therefrom. When the cam 36 is completely rotated (FIG. 3A). the slide means 28 carrying the stripping and cutting means 13 and the lower clamp 30 is moved downwardly. Thus, a first stripped end E, has now been completely formed in readiness for wrapping (see FIG. 9).

At this point. a more detailed look at the structure of the tool 15 should be taken. The bit element has an aperture 91 formed in its free end for receipt of the terminal t to be wrapped. The free end projects outwardly beyond the main frame 11 at all times so as to be capable of engaging said terminals! without interference. The bit element is held stationary. both in the rotary and axial sense. by a locking screw 92 engaging the same at the rear of the main frame 11, as shown in FIG. 1. A notch 93 is formed in the side of the stationary bit element 90 for side loading of the wire W. as shown by the prepared end E, in FIG. 9A. The side loading feature is particularly advantageous in automatic wrapping since this leaves the face of the main frame 11 free from structure that would interfere with the movement ofthe tool to the terminal board B. The tips of the gripper jaws 18. 19 when moved to the full forward position with the tool 15 fit between the adjacent space between horizontal rows of terminals r. and due to the offset of the stationary jaw 19 conflict with the adjacent terminal I in the vertical direction is also avoided. Wires already in position from previous operations are tucked in between the terminals 1 by the tips for a neater finished product.

The tool 15 further comprises a rotatable and axially movable sleeve 95 mounted concentrically on the bit element 90. The sleeve 95 is the part that is directly attached to the gear 71 and is thus driven thereby. The sleeve is mounted in suitable bearings in the sliding support 15a and may be held in position by suitable expandable clips to allow removal as necessary when the tool has become worn. The operative face 96 of the tool engages the wire as it is being wrapped thereby causing the greatest area of wear and necessitating the periodic replacement. The face 96 is provided with projecting camming area 97 that serves to push each wrap of the wire snug against the previous wrap as the sleeve rotates.

The sleeve 95 has a longitudinal slot opening adjacent the bottom. as orientated in FIG. 9A. The slot is bisected by the stationary bit element 90, and thereby forms a closed groove 98 and an open groove 99 contiguous with the bit element 90 (see FIG. 11). The upper groove has. of course. less radial extent and is designed to hold the stripped end of the wire W when the end is ready for wrapping. The lower groove 99 is designed to simply allow free passage of the stripped end E, as it is drawn in by the notch 93

Claims

1. Apparatus for placing magnet wire in slots respectively defined by the blades of coil transfer apparatus which lie on an imaginary cylinder to form a circular dynamoelectric machine field winding, said apparatus comprising means for guiding said wire toward said blades, means for pushing wire through said guide means without applying tension thereto, and means for moving said guide means relative to said blades in a circular path which overlaps said cylindrical array of blades and which is aligned with the open ends of two of said slots whereby said wire is pushed in a direction away from the center of said path and is also pushed into said two slots.

2. The apparatus of claim 1 wherein said blades respectively have distal ends and proximal ends mounted on a support member, said slots having open ends defined by said distal ends, said cylinder having a first axes, said guide means including a gun member having a dispensing end spaced from and extending generally radially with respect to a second axis which is spaced from said cylinder and parallel with said first axis, said dispensing end lying in a plane spaced from said distal ends on the side thereof remote from said support member, said moving means including means for rotating said dispensing end about said second axis whereby said dispensing end pushes said wire in said circular path, the spacing of said dispensing end from said second axis and the ratio of the speeds of said pushing and moving means being proportioned and arranged so that said path overlaps said cylinder and is aligned with said open ends of two of said slots whereby said wire is pushed into said two slots.

3. The apparatus of claim 2 wherein said gun member comprises an elongated tube having an end opposite said dispensing end, said opposite end being adjacent said pushing means and lying on said second axis.

4. The apparatus of claim 3 further comprising means concentrically surrounding said dispensing end and radially spaced therefrom for confining said wire in said path.

5. The apparatus of claim 4 wherein said confining means comprises an annular member having a frusto-conical inner surface facing and spaced radially from said dispensing end, said surface tapering inwardly in the direction away from said distal ends of said blades.

6. The apparatus of claim 5 further comprising means for selectively, axially moving said annular member with respect to said dispensing end from a first position in which said wire pushed from said dispensing end impinges on said inner surface at first points lying on a first circle thereon whereby said wire is pushed in a first circular path having a first diameter, said first path being aligned with the open ends of a first two of said slots, and a second position in which said wire pushed from said dispensing end impinges on said inner surface at second points lying on a second circle thereon whereby said wire is pushed in a second circular path having a second diameter smaller than said first diameter, said second path being aligned with the open ends of a second two of said slots intermediate said first two slots.

7. The apparatus of claim 6 wherein said annular member is moved axially from said first to said second position thereof in a direction toward said support member, said annular member having slots therein for receiving said distal ends of certain of said blades at least in said second position.

8. The method of placing magnet wire in slots respectively defined by the blades of coil insertion apparatus which lie on an imaginary cylinder to form a circular dynamoelectric machine field winding, said method comprising the steps of advancing said wire by pushing the same on its axis without applying tension thereto, and guiding said wire as it is being pushed in a circular path, which overlaps said cylindrical array of blades and which is aligned with the open ends of two of said slots whereby said wire is pushed in a direction away from the center of said path and is also pushed into said two slots.

9. The method of claim 8 wherein said path is about an axis spaced from said cylinder and parallel with said cylinder axis.

10. The method of claim 9 comprising the further steps of confining said wire as it is being pushed to a first circular path having a first diameter and aligned with the open ends of a first two of said slots, and confining said wire as it is being pushed to a second circular path having a second diameter smaller than said first diameter and aligned with the open ends of a second two of said slots intermediate said first two slots thereby forming concentric windings.