US3661251A

US3661251A - Strip of fasteners in a predetermined sequence

Info

Publication number: US3661251A
Application number: US136589A
Authority: US
Inventors: Ronald Waeltz
Original assignee: Standard Pressed Steel Co
Current assignee: SPS Technologies LLC
Priority date: 1971-04-22
Filing date: 1971-04-22
Publication date: 1972-05-09
Anticipated expiration: 1989-05-09

Abstract

Equipment for setting fasteners in a tape or strip of flexible and resilient material from which the fasteners may be automatically inserted into workpieces. The fasteners are carried in holes in the tape which are formed to accommodate different types or size fasteners. In addition, these holes may be barrelled to enhance the alignment of the fasteners for their insertion into the workpieces.

Description

United States Patent Waeltz [54] STRIP OF FASTENERS IN A PREDETERMINED SEQUENCE [72] Inventor: Ronald Waeltz, Hatboro, Pa.

[73] Assignee: Standard Pressed Steel Co., Jenkintown,

[22] Filed: Apr. 22, 1971 [21] App1.No.: 136,589

Related US. Application Data [601 Continuation of Ser. No. 8,106, Jan. 20, 1970, abandoned, which is a division of Ser. No. 641,754, May 29, 1967, Pat. No. 3,495,315.

52 U.S. C1 ..206/56 DF, 206/56 A, 227/136 51 ..B65d 83/00 58 Field of Search ..24 73 R, 73 B, 73 MF, 73 BP,

24/73 AS, 73 BC, 73 SA, 81 R; 161/46; 206/56 A, 56 AC, 56 DF, 59 E, 63.4; 227/136 51 May 9,1972

[56] References Cited UNITED STATES PATENTS 1,168,760 1/1916 Sworzyn ..206/44.1| 2,823,789 2/1958 Henning..... 206/56 A UX 2,599,01 1 6/1952 Phipard, Jr. ..206/79 3,097,360 7/1963 Carlson, Jr. et al... 206/56 DF 3,165,968 l/1965 Anstett ....206/56 DF 3,211,284 10/1965 Anstett.... .....206/56 DF Primary Examiner-Joseph R. Leclair Assistant E.\'aminer-Steven E. Lipman Attorney-Stanley Belsky [57] ABSTRACT Equipment for setting fasteners in a tape or strip of flexible and resilient material from which the fasteners may be automatically inserted into workpieces. The fasteners are carried in holes in the tape which are formed to accommodate different types or size fasteners. In addition, these holes may be barrelled to enhance the alignment of the fasteners for their insertion into the workpieces.

6 Claims, 4 Drawing Figures PATENTEDMAY 91972 3,661,251

sum 2 BF 2 INVENTOR. R0 NMD WAELTZ ATTORNEY STRIP F FASTENERS IN A PREDETERMINED SEQUENCE This application is a continuation of Ser. No. 8,106 filed Oct. 20, 1970, now abandoned, which is a division of application Ser. No. 641,754 filed May 29, 1967, now US. Pat. No. 3,495,315.

The present invention relates, in general, to the automatic application of fasteners to workpieces and, in particular, to apparatus for arranging fasteners on a tape or strip of flexible and resilient material so that the fasteners may be engaged by a power tool and inserted into workpieces.

Presently, much time and effort is being devoted to the design and development of machinery which will permit various manufacturing and assembly operations to be performed automatically. Among the types of equipment receiving such attention are machines for setting fasteners automatically. Despite the demand for such units, their use is not as widespread as might be expected because those machines which are presently available suffer from one or more serious shortcomings. For example, while the use of certain automatic fastener setting machines results in a great savings of time and money for users of large numbers of fasteners, these machines have been found to be economically undesirable for users of small quantities of fasteners. Another limitation of these machines is that they lack the flexibility and versatility needed to satisfy modern-day requirements. Generally, a particular machine is arranged to set only one type or size fastener and is not able to handle different fasteners sequentially.

Accordingly, it is an object of the present invention to provide new and improved apparatus for arranging fasteners to be set automatically.

It is a further object of the present invention to provide such apparatus which may be fabricated and operated at reasonable cost to most users.

It is yet a further object of the present invention to provide such apparatus which is flexible and versatile so that different fasteners may be handled and set in a predetermined sequence corresponding to a particular need.

In accordance with one embodiment of the present invention, fasteners are inserted into holes punched in a tape or strip of flexible and resilient material in such a manner that each fastener lies in yielding frictional engagement with the walls of its associated hole. The fasteners may be of the same type or they may vary from one to the next. The holes, shaped and dimensioned according to the associated fasteners, are punched into the tape at prescribed points corresponding to the particular sequence in which the fasteners will be needed for insertion into workpieces. This mode of operation may be termed programmed loading of fasteners. The tape, thus loaded with fasteners, is adapted to be fed past a power tool so that the fasteners may be ejected from the tape and set into workpieces as the drive element of the tool is projected against the fasteners and through the holes.

The holes in the tape preferably are barrelled and formed of the strip material as the holes are punched and the material is pushed outward and stretched. Such construction enhances the alignment of a fastener as it is carried by the tape and positioned with respect to the powered tool, thereby reducing the possibilities of operational failures.

For a better understanding of the present invention, together with other and further objects thereof, reference is made to the following description, taken in connection with the accompanying drawings, and its scope will be pointed out in the appended claims.

Referring to the drawings:

FIGS. la and lb are schematic diagrams of the loading and ejecting portions, respectively, of an automatic fastener setting system constructed in accordance with the present invention;

FIG. 2 is a sectional view of a part of the loading portion of FIG. la; and I FIG. 3 is a perspective view, on an enlarged scale, of a length of a tape employed for carrying fasteners in accordance with the present invention.

Referring to FIGS. la and 2, a tape or strip 10 of flexible and resilient material is loaded with fasteners at a loading station, designated generally by reference numeral 12. The tape 10 is supplied from a supply reel 14 and may be a suitable plastic material.

The first operation performed at the loading station 12 is the punching of a pair of upper and lower sprocket holes 16a and 16b into the tape 10. Sprocket holes 16a and 16b are punched by a pair of reciprocating

punches

18a and 18b, respectively, which are ganged together and actuated by a punch drive mechanism 20 at prescribed times in a manner to be described hereinafter. The punches 18a and 18!: are guided through the tape 10 by a pair of bores in a block 21 having a slot through which the tape passes.

The sprocket holes 16a and 16b are engaged by pairs of upper and

lower sprockets

22a and 22b, respectively, carried on an indexing wheel 24. The indexing wheel 24 is coupled through a shaft 26 to a wheel drive mechanism 28 which effects incremental rotational movements of the indexing wheel at prescribed times in a manner to be described hereinafter. It is these incremental movements of the indexing wheel 24 and the engagement of the sprockets 22a and 2212 with the holes 16a and 16b which draws the tape 10 toward the loading station 12 and moves the tape through the loading station.

As the tape 10 is moved through the loading station 12, fastener holes are punched into the tape by two

reciprocating punches

30 and 32 which are actuated by punch drive mechanisms 34 and 36, respectively, at prescribed times in a manner to be described hereinafter. Positioned on the opposite side of tape 10 from the

punches

30 and 32 are two reciprocating

blocks

31 and 33 which are provided with

wells

31a and 330, respectively, aligned with these punches and adapted to receive the forming ends of

punches

30 and 32, respectively. The reciprocating

blocks

31 and 33 are actuated by block drive mechanisms 35 and 37, respectively, at prescribed times in a manner to be described hereinafter. The purpose for moving

blocks

31 and 33 to and away from tape 10 is to provide a base against which the tape bears as the holes are being punched and to permit the tape to move freely afterward. The particular sizes and shapes of the forming ends of

punches

30 and 32 and the wells 31a and 33a correspond to the sizes and shapes of the fasteners which are to be inserted into the holes punched by

punches

30 and 32. The forming end of punch 30 is slightly larger than that of punch 32 so that the holes developed by punch 30 are adapted to receive fasteners of a slightly larger size. The relative sizes of these holes and their associated fasteners are such that each of the fasteners inserted into these holes lies in yielding frictional engagement with the walls of a hole. The

punches

30 and 32 preferably are rotated as they pierce and project through tape 10. As a result, the holes developed by

punches

30 and 32 are more uniformly round.

As most clearly illustrated in FIGS. la and 2, the forming ends of each of the

punches

30 and 32 have a starting tip (30a, 32a), a first bevelled section (30b, 32b), a cylindrical section (300, 32c), and a second bevelled section (30d, 32d). As a result, the holes punched by

punches

30 and 32 are barrelled. The barrelling effect is formed as the flexible and resilient material of the strip 10 is pushed outward and is stretched by the punches as the different sections of the forming ends of the punches are projected through the strip. In particular, tape 10 is first pierced and then subjected to the increasing diameters of the sections of the forming ends of the punches. By barrelling the holes, the alignment of the fasteners subsequently inserted is enhanced. The barrelling offsets the tendency of a fastener having an external thread, for example, from being skew. FIG. 3 shows a length of tape 10 after the barrelled holes have been punched and two fasteners have been inserted in two of the holes.

After the barrelled holes are punched by

punches

30 and 32, fasteners such as the

setscrews

42 and 44 may be loaded onto the tape 10. Setscrews 42, being slightly larger in diameter than setscrews 44, are inserted into the holes punched by punch 30, while setscrews 44 are inserted into the holes punched by punch 32. The

setscrews

42 and 44 are supplied along chutes 46 and 48, respectively, to a pair of

grooved beds

50 and 52, respectively. The

setscrews

42 and 44 are pushed off of the

beds

50 and 52 by a pair of

reciprocating plungers

54 and 56, respectively which are aligned with the beds and are actuated by plunger drive mechanisms 58 and 60, respectively, at prescribed times in a manner to be described hereinafter. Positioned on the opposite side of tape from the

plungers

54 and 56 are two reciprocating blocks 55 and 57 which are provided with wells 55a and 57a, respectively, aligned with these plungers and adapted to receive the barrelled holes in the tape and the

setscrews

42 and 44. The well 55a is slightly larger than the well 57a to receive the larger setscrew. The

plungers

54 and 56 drive the

setscrews

42 and 44 into the barrelled holes in tape 10 and the wells 55a and 57a. The reciprocating blocks 55 and 57 are actuated by

block drive mechanisms

59 and 61, respectively, at prescribed times in a manner to be described hereinafter. The purpose for moving blocks 55 and 57 to and away from tape 10 is to provide a base against which the tape bears as the setscrews are being inserted and to permit the loaded tape to move freely afterward.

After the insertion of

setscrews

42 and 44, the loaded tape 10 is drawn away from the loading station by indexing wheel 24. The loaded tape may be wound on a storage reel or held in a suitable container for subsequent use.

The operation of

punch drive mechanisms

20, 34 and 36, wheel drive mechanism 28, plunger drive mechanisms 58 and 60 and

block drive mechanisms

35, 37, 59 and 61 is controlled by a control unit 70. The output lines 70a-70j, inclusive, from control unit 70 extend to the

various drive mechanisms

20, 34, 36, 28, 58, 60, 35, 37, 59 and 61, but have been shown broken for the sake of clarity. The output lines 70a-70j carry control signals which operate the associated drive mechanisms which, in turn, actuate the respective punches, plungers, blocks and the indexing wheel.

Various modes of operation may be employed at the loading station 12. The various punches, plungers and blocks may be actuated sequentially or simultaneously or a combination of the two. While one mode of operation and variations thereof will be described, others will become readily apparent. Whatever mode of operation is chosen, the control unit 70 may be designed accordingly.

At the outset, the leading end of tape 10 is provided with a few pairs of sprocket holes 16a and 16b to start the movement of the tape through the loading station 12. If the loaded tape is to be collected on a storage reel, the leading end of the tape is wound onto this reel.

Punches

18a, 18b, 30 and 32 are actuated simultaneously by three times coincident signals directed to punch

drive mechanisms

20, 34 and 36 from the control unit 70 along

output lines

70a, 70b and 70c. At the same time, blocks 31 and 33 are moved to tape 10 by two signals directed to block drive mechanisms 35 and 37 from the control unit 70 along output lines 70d and 70e. Thus, a pair of sprocket holes and a pair of barrelled fastener holes are punched in tape 10. Next, a control signal is supplied from control unit 70 along line 70f to wheel drive mechanism 28 to turn the indexing wheel 24 through a prescribed angle to position the two fastener holes, just punched, in front of

beds

50 and 52.

At this time,

plungers

54 and 56 are actuated simultaneously by two time coincident signals directed to plunger drive mechanisms 58 and 60 from the control unit 70 along

output lines

70g and 70h. At the same time, blocks 55 and 57 are moved to tape 10 by two signals directed to block

drive mechanisms

59 and 61 from the control unit 70 along output lines 70i and 70j. If desired, the

punches

18a, 18b, 30 and 32 and the

blocks

31 and 33 also may be actuated at this time to punch the next set of sprocket and fastener holes. Thus, after the first set of fastener holes have been punched, the punching of holes and the insertion of fasteners may take place simultaneously. The indexing wheel 24 is driven through its incremental movement after each hole punching and fastener insertion cycle.

Referring to FIG. lb, which illustrates the ejecting portion of the system, the loaded tape 10 is supplied to an ejecting station, designated generally by reference numeral 80, from a storage reel or container. The loaded tape 10 is drawn past the ejecting station by a driven sprocket wheel 82. The sprocket wheel 82 undergoes timed, incremental rotations so as to position the

setscrews

42 and 44 sequentially in front of a reciprocating plunger 84 which is actuated by a plunger drive mechanism 86. The plunger 84 is actuated every time the tape 10 comes to rest. Setscrews 42 and 44 are driven from the barrelled holes in tape 10 as the plunger 84 is projected against the setscrews and through the holes in the tape. Specifically, the leading end of plunger 84 may be hexagonal in cross-section and adapted to enter correspondingly shaped wells in

setscrews

42 and 44. As the setscrews are ejected from the tape, they are guided through a bore 88 in a block 90 located forward of the tape 10. A workpiece (not shown) normally is positioned in front of block 90 so that it may receive the setscrews. Besides imparting longitudinal movements of plunger 84, plunger drive mechanism 86 also imparts a rotational movement to plunger 84 so that the setscrew may be seated in the workpiece.

While there have been described what are at present considered to be the preferred embodiments of this invention it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention and it is, therefore, aimed to cover all such changes and modifications as fall within the true spirit and scope of the invention.

What is claimed is:

1. A fastener strip comprising a strip of flexible and resilient material having a plurality of barrelled holes of at least two different sizes spaced along said strip in a predetermined sequence and formed of said flexible and resilient material as holes are punched in said strip through the thickness thereof and said flexible and resilient material is pushed outward and stretched.

2. A fastener strip comprising a strip of flexible and resilient material having a plurality of barrelled holes of at least two different sizes spaced along said strip in a predetermined sequence and adapted to receive a plurality of correspondingly sized fasteners, each of said bar-relled holes formed of said flexible and resilient material as holes are punched in said strip through the thickness thereof and said flexible and resilient material is pushed outward and stretched.

3. A fastener strip comprising:

a strip of flexible and resilient material having a plurality of holes of at least two different sizes spaced along said strip in a predetermined sequence and extending through the thickness of said strip; and

a plurality of fasteners of at least two different sizes positioned in correspondingly sized holes in said strip, each of said fasteners lying in yielding frictional engagement with the wall of a hole in said strip, whereby said fasteners may be driven from said holes as a drive element is projected against said fasteners and through said holes.

4. A fastener strip comprising:

a strip of flexible and resilient material having a plurality of barrelled holes of at least two different sizes spaced along said strip in a predetermined sequence and formed of said flexible and resilient material as holes are punched in said strip through the thickness thereof and said flexible and resilient material is pushed outward and stretched; and

5. A fastener strip according to claim 1 wherein said barrelled holes are arranged in a repetitive predetermined sequence.

6. A fastener strip according to claim 3 wherein said barrelled holes and fasteners are arranged in a repetitive predetermined sequence.

Claims

2. A fastener strip comprising a strip of flexible and resilient material having a plurality of barrelled holes of at least two different sizes spaced along said strip in a predetermined sequence and adapted to receive a plurality of correspondingly sized fasteners, each of said barrelled holes formed of said flexible and resilient material as holes are punched in said strip through the thickness thereof and said flexible and resilient material is pushed outward and stretched.

3. A fastener strip comprising: a strip of flexible and resilient material having a plurality of holes of at least two different sizes spaced along said strip in a predetermined sequence and extending through the thickness of said strip; and a plurality of fasteners of at least two different sizes positioned in correspondingly sized holes in said strip, each of said fasteners lying in yielding frictional engagement with the wall of a hole in said strip, whereby said fasteners may be driven from said holes as a drive element is projected against said fasteners and through said holes.

4. A fastener strip comprising: a strip of flexible and resilient material having a plurality of barrelled holes of at least two different sizes spaced along said strip in a predetermined sequence and formed of said flexible and resilient material as holes are punched in said strip through the thickness thereof and said flexible and resilient material is pushed outward and stretched; and a plurality of fasteners of at least two different sizes positioned in correspondingly sized holes in said strip, each of said fasteners lying in yielding frictional engagement with the wall of a hole in said strip, whereby said fasteners may be driven from said holes as a drive element is projected against said fasteners and through said holes.