US3900132A

US3900132A - Apparatus for handling parts

Info

Publication number: US3900132A
Application number: US401236A
Authority: US
Inventors: Donald E Kuehn; John Keith Lyon
Original assignee: TRW Inc
Current assignee: Northrop Grumman Space and Mission Systems Corp
Priority date: 1973-09-27
Filing date: 1973-09-27
Publication date: 1975-08-19
Anticipated expiration: 1992-08-19
Also published as: DE2443132A1; FR2245452A1; GB1481996A; CA1020185A; FR2245452B1; JPS5059874A; AU7038474A

Abstract

Apparatus is provided for handling parts and particularly for feeding fasteners to a transfer station. The fasteners are fed in an oriented, sequential manner to the transfer station from which they are moved into contact and assembled with a workpiece. The fasteners have flat portions or flanges which tend to overlap or shingle and can cause jamming or malfunctioning at the transfer station. To overcome this, fingers are provided which engage the second fastener being fed sequentially and reverse its direction to separate it from the first fastener, thereby preventing jamming even if the flanges had been overlapped. The fingers are automatically operated by a punch or ram which assembles the fasteners with the workpiece. The fingers are also provided with resilient safety means to prevent operation of the fingers in the event that a jam occurs.

Description

United States Patent [191 Kuehn et a1.

[ APPARATUS FOR HANDLING PARTS [75] Inventors: Donald E. Ku'ehn, Bay Village; John Keith Lyon, Wellington, both of Ohio [73] Assignee: TRW Inc., Cleveland, Ohio [22] Filed: Sept. 27, 1973 21 Appl. No.: 401,236

[ Aug. 19, 1975 Primary Examiner-Stanley H. Tollberg Attorney, Agent, or Firm-Allen D. Gutchess, Jr.

[57] ABSTRACT Apparatus is provided for handling parts and particularly for feeding fasteners to a transfer station. The fasteners are fed in an oriented, sequential manner to the transfer station from which they are moved into contact and assembled with a workpiece. The fasteners have flat portions or flanges which tend to overlap or shingle and can cause jamming or malfunctioning at the transfer station. To overcome this, fingers are provided which engage the second fastener being fed sequentially and reverse its direction to separate it from the first fastener, thereby preventing jamming even if the flanges had been overlapped. The fingers are automatically operated by a punch or ram which assembles the fasteners with the workpiece. The fingers are also provided with resilient safety means to prevent operation of the fingers in the event that a jam occurs.

19 Claims, 15 Drawing Figures PATENTEDAUG] 91% 3,900,132

FIG. 1 f

PATENIEBAUWM 132 APPARATUS FOR HANDLING PARTS This invention relates to apparatus for handling parts and particularly for automatically feeding fasteners to a transfer station from which they are assembled with workpieces.

Fasteners of the type with which the present inven tion is concerned have portions which can overlap when the fasteners are fed in a sequential, oriented manner. The particular fasteners have cylindrical portions forming threaded Openings with integral flanges at ends of the cylindrical portions having prongs extending transversely from the edges of the flanges. The cylindrical portions are received in holes in workpieces of wood or other material, with the prongs being driven into the material around the holes. Bolts or machine screws can then be threaded into the openings to assemble other components with the workpieces. Typically, the fasteners of this type are used in furniture construction but have heretofore been assembled only by hand.

The overall apparatus in accordance with the inven tion orients the fasteners, feeds them sequentially to a transfer station, and moves them from the transfer station into assembled relationship with the workpiece. Twenty or more fasteners can be assembled with workpieces per minute, as compared with only a few when assembled by hand, as done heretofore.

When the fasteners are fed sequentially to a transfer station or escapement unit, peripheral portions of the flanges tend to overlap occasionally and when this occurs, a malfunction or jam can result when the first fastener is attempted to be fed from the transfer station into assembled relationship with the workpiece. To overcome this, in accordance with the invention, fingers are provided at the escapement unit which engage the second fastener in the line and reverse its direction of movement away from the first fastener, to separate them and enable the first fastener to be fed to the workpiece free and clear of the second fastener and those therebehind. Hence, even if a shingling or overlapping relationship occurred, this will be eliminated before the first fastener is fed to the workpiece. The fingers are automatically operated by the same ram or moving member which moves the first fastener from the trans fer station to the workpiece. Further, safety provisions are incorporated which prevent the fingers from moving the second fastener in the reverse direction in the event of upstream jamming, which could otherwise damage the apparatus or fasteners.

It is, therefore, a principal object of the invention to provide improved apparatus for automatically feeding fasteners having cylindrical portions and flanges into assembled relationship with workpieces.

Another object of the invention is to provide apparatus for handling fasteners which separates the fasteners at a transfer station, thereby preventing any problem resulting from overlapping.

A further object of the invention is to provide an improved escapement unit for handling fasteners with resilient or yieldable means for preventing operation in the event of certain types ofjams.

Many other objects and advantages of the invention will be apparent from the following detailed description of a preferred embodiment thereof, reference being made to the accompanying drawings, in which:

FIG. 1 is a somewhat schematic front view in elevation of overall apparatus for orienting fasteners, feeding them sequentially to a transfer station, and moving the fasteners into assembled relationship with a workpiece;

FIG. 2 is an enlarged, fragmentary view in elevation of the transfer station or escapement unit of FIG. 1;

FIG. 3 is a fragmentary bottom view taken along the line 3-3 of FIG. 2;

FIG. 4 is a fragmentary top view taken along the line 44 of FIG. 3;

FIG. 5 is a fragmentary view in vertical cross section taken along the line 5-5 of FIG. 4;

FIGS. 6 and 7 are views similar to FIG. 5 but with the components shown in progressive positions;

FIG. 8 is a view in transverse cross section taken along the line 88 of FIG. 2;

FIG. 9 is a view similar to FIG. 8 but with components shown in a different position;

- FIG. 10 is an enlarged, fragmentary bottom view of the fasteners shown in FIG. 3;

FIG. 11 is a view similar to FIG. 10 but showing the fasteners separated;

FIG. 12 is a view in transverse cross section taken along the line l2-12 of FIG. 5;

FIG. 13 is a fragmentary view similar to FIGS. 5-7 but showing the components in a still different position;

FIG. 14 is a fragmentary view in longitudinal cross section taken through the ram used with the apparatus to move the fasteners from the transfer station to the workpieces; and

FIG. 15 is a perspective view of a fastener in assembled relationship with a workpiece.

Referring to the drawings, and particularly to FIG. 1, overall fastener handling apparatus is indicated at 10 and includes a vibratory feeder 12 having a vibratory bowl 14 with a spiral ramp (not shown) therein and a drive unit 16. Parts or fasteners with which the invention is specifically concerned are indicated at 18 and move up the ramp in the bowl 14 under the influence of the vibratory action and enter a feed track or guide means 20. The fasteners are fed sequentially in an oriented manner to an escapement unit 22 constituting a transfer station from which the fasteners 18 are moved by a ram or moving means 24 to a workpiece 26, which is shown as a block of wood constituting a component of an article of furniture. The workpiece 26 is supported on a suitable stand or fixture 28 and an upper housing 30 contains suitable drive mechanism and controls for the overall apparatus 10.

The fastener 18, when assembled with the workpiece 26, is shown more particularly in FIG. 15. The fastener 18 includes a central cylinder 32 forming a threaded opening 34 which receives a machine screw or bolt from the lower side of the workpiece 26. The fastener 18 also includes a generally circular flange or flat portion 36 from the edges of which prongs 38 extend in a direction generally parallel to the cylinder 32. The cylinder 32 is forced into a pre-drilled hole 40in the workpiece 26 and the prongs 38 penetrate the workpiece 26 by the force of the ram 24. For some workpieces and fasteners, it is possible for the cylinder 32 to be forced into the workpiece26 without requiring any previous drilled hole, the cylinder 32 forming its own hole therein.

When the fasteners 18 are fed sequentially down the track 20, it is possible for certain peripheral portions or edges 42 to overlap or shingle. This can cause jamming or malfunctioning particularly if it occurs when the first one of the overlapping fasteners 18 is to be moved by the ram 24 toward the workpiece 26.

The feed track 20, as shown in FIGS. 2 and 3, for example, is made of a generally shallow, inverted U- shaped upper strip 44 and two lower,

inwardlyextending flanges

46 and 48 forming a slot 50. The flange 36 of the fastener 18 rides on the upper surfaces of the

flanges

46 and 48 with the cylinder 32 and the prongs 38 extending through the slot 50 to maintain the fasteners 18 oriented with respect to the feed track. Since the peripheral portions 42 of the fastener flanges are in contact with one another as the fasteners move down the track, they are subject to the possibility of overlapping and causing a problem at the escapement unit 22, the overlapping being shown in FIGS. and 10.

The escapement unit 22 is supported by brackets 52 and 54 (FIG. 2) depending from the upper housing 30, the unit comprising a main escapement body 56 and a cover 58. A passage 60 is formed in the body 56 as an extension of the track 20, the passage being formed in part by a web 62 (see also FIG. 12) and two

pair

64 and 66 of spring-loaded feet 68. The four feet of the two

pair

64 and 66 are substantially similar and only one will be discussed in detail. Each of the feet 68 has an upwardly-extending leg 70 (FIGS. 8 and 9) located in a slot 72 of the escapement body 56 and is pivotally held therein by a pin 74. The legs have extensions 76 which are contacted by springs 78 located in recesses 80 of the body 56 to urge the feet 68 inwardly, below the passage 60. In this position, the inner extremities of the feet 68 are spaced apart less than the distance across the fastener flanges 36, thereby retaining the fasteners 18 in the passage 60 after leaving the track 20.

The first pair 64 of the feet 68 holds the first fastener in the path of the ram 24 which moves through a vertical passage 82. The feet yield outwardly as the ram moves downwardly in a predetermined path to move the fastener toward the workpiece 26.'After the fastener passes, the feet 68 return to their normal position because the minimum space between them exceeds the thickness of the ram 24 across the flats thereof (FIG. 3). The feet 68 are then in position to support the next one of the fasteners 18 moving down the track and the passage 60. The second pair 66 of the feet 68 retain the second one of the fasteners 18 in position adjacent the first fastener with the second pair yielding to enable a fastener to be forced downwardly and outwardly only if it is in an intermediate position and not aligned with the ram 24.

To prevent a problem from occurring if the edges 42 of the fasteners 18 should overlap, particularly with the type of overlap of FIG. 5, the second one of the fasteners 18 in the row is engaged and physically moved back from the first one of the fasteners 18 located in the path of the ram 24 under the passage 82. To accomplish this, with reference to FIGS. 5-7 and 12, a carrier 82 consists of two parts 84 and 86 held together by a fastener 88 with fingers or engaging

means

90 and 92 extending into

slots

94 and 96 in the web 62 of the body 56. The carrier 82 is mounted on a pin 98 which extends into vertical notches or recesses 100 in the body 56. The ends of the pin 98 are urged upwardly by coil springs 102 located in vertical blind passages 104 in the escapement body 56. With this arrangement, the carrier 82 is urged upwardly toward the cover 58 so that the lower extremities of the

fingers

90 and 92 are above the lower surface of the web 62, leaving the passage or guide means clear and unobstructed (FIGS. 5 and 12).

The carrier 82 also has a cam member or engageable means 106 extending into the path of the ram 24 and into the passage 82. When the ram 24 moves downwardly, it engages an upper slanted surface 108 of the cam member 106, thereby placing a downward and rearward force on the carrier 82. The carrier thereby moves downwardly as shown in FIG. 6 with the pin 98 moving downwardly in the notches until the pin reaches the bottom of them. At this time, the

fingers

90 and 92 extend downwardly into the passage 60 and specifically between the peripheral edges of the flanges 36 of the first two fasteners 18 (FIG. 10). Since the carrier 82 cannot move downwardly any further, and the cam member 106 is still in the path of the ram 24, the carrier must move in a clockwise direction, as shown in FIG. 7. This causes the

fingers

90 and 92 to engage the periphery of the second one of the fasteners 18 and move it rearwardly, in the direction from which it came. This separates the first two fasteners and overcomes any overlapping or shingling positions thereof.

In moving clockwise, the carrier engages a plunger 110 (FIG. 7) located in a passage 112 of the escapement body 56. This movement of the plunger 110 compresses a coil spring 114 located around a plunger shank 116, the spring being retained by a setscrew 118. When the ram retracts again, the spring 112 causes the carrier 82 to move back to the position of FIG. 6, and the pair of springs 102, acting on the pin 98, moves the carrier 82 upwardly to the position of FIG. 5. The

fingers

90 and 92 thus clear the passage 60, enabling the fasteners 18 to move sequentially forwardly again, with the next one moving into the path of the ram 24.

In the event that the fasteners 18 in the track 20 become jammed between the escapement unit 22 and the bowl 14, damage could result to the apparatus as the

fingers

90 and 92 attempted to force the second one of the fasteners 18 rearwardly. To prevent this possibility, the cam member 106 is yieldably carried by the carrier 82 to prevent movement of the

fingers

90 and 92 in the event of the aforesaid jamming. Referring particularly to FIGS. 12 and 13, the cam member 106 is separate from the carrier 82, being located in a passage therein. This passage restricts movement of the cam member 106 in a path generally transverse to the movement of the ram 24. The cam member 106 has a transverse passage 122 therein containing a coil spring 124 which urges two balls 126 outwardly toward notches or recesses 128 formed in the carrier parts 84 and 86. When the cam member 106 is in the forward position relative to the carrier 82, as shown in FIG. 5, the balls 126 project into the notches 128 and hold the cam member 106 in that position. In the event ofjamming, however, so that the

fingers

90 and 92 cannot move rearwardly, the balls are forced out of the notches and the cam member moves to the position of FIG. 13 as the ram 24 moves downwardly. The cam member 106 will subsequently be returned to the forward position with the balls in the notches and with an upper flange 130 contacting the rear edge of the carrier 82, through the action of the coil spring 114.

Referring particularly to FIG. 14, the ram 24 has magnets 132 in the lower end to help retain the fastener as it is moved toward the workpiece. The ram 24 also has a punch 134 with a lower tapered end 136 projecting through the cylinder 32 of the fastener 18. If a jam should occur or if an attempt is made to fasten one of the fasteners 18 in a workpiece already containing a fastener, the punch 134 is preferably spring loaded. As shown, the punch has a narrow portion 138 terminating in an upper enlargement 140 with a fastener 142 having an end projecting into the space between the main part of the punch and the enlargement 140, at the narrow portion 138. This limits the maximum upward and downward movement of the punch 134, the punch being urged downwardly by a spring 144. If a fastener already exists in the workpiece, the punch 134 will retract into the ram 24 without damaging the apparatus, the end of the ram 24 simply deforming the second one of the fasteners 18.

In the event that the fasteners 18 are assembled into the wooden workpieces 26 without first forming holes in the workpieces, the punch 134 is rigidly mounted relative to the ram 24. The punch then helps to form the hole in the workpiece 26 along with the cylinder 32 of the fastener 18 from which the punch projects somewhat.

Various modifications of the above-described emvbodiment of the invention will be apparent to those skilled in the art, and it is to be understood that such modifications can be made without departing from the scope of the invention, if they are within the spirit and the tenor of the accompanying claims.

We claim:

1. Apparatus for handling parts comprising means forming a transfer station, moving means for moving parts from said transfer station along a given path, guide means for directing parts sequentially into the path, part-control means including engagable means engagable by said moving means and engaging means for engaging a part adjacent said path, said engaging means moving that part away from said path when said engagable means is engaged by said moving means, and yieldably-mounted feet for yieldably holding the first part in the path of said moving means.

2. Apparatus for handling parts comprising means forming a transfer station, means for moving parts along a given path from said transfer station, guide means for directing parts sequentially into said path, and means engageable by said moving means for engaging a part adjacent the path and for moving that part away from the path, said engageable means being movable from a position spaced from said guide means to a second position in which a portion of said engageable means projects into said guide means, and to a third position in which said portion projects into said guide means but is farther away from the path of said moving means.

3. Apparatus according to claim 2 characterized by said engageable means being out of the path of said moving means when in the third position.

4. Apparatus for handling parts comprising means forming a transfer station, a source of parts. guide means for feeding parts sequentially from said source to said transfer station, a member having engaging means for engaging parts along said guide means for temporarily moving those parts along said guide means in the opposite direction from which they are fed, said member having a position in which said engaging means is clear of said guide means and a position in which said engaging means projects into said guide means, and resilient means urging said member to the position in which said engaging means is clear of said guide means.

5. Apparatus for handling parts comprising means forming a transfer station, moving means for moving parts from said transfer station along a given path, guide means for directing parts sequentially into the path, part-control means including engagable means engagable by said moving means and engaging means for engaging a part adjacent said path, said engaging means moving that part away from said path in a direction opposite to the direction the parts move along the guide means, when said engagable means is engaged by said moving means.

6. Apparatus according to claim 5 characterized by said engaging means being movable from a position spaced from said guide means to a position in which said engaging means project into said guide means, and to a third position in which said engaging means project into said guide means but is farther away from said path.

7. Apparatus according to claim 6 characterized by said engageable means being in the path of said moving means when said engaging means is in the first and sec ond positions.

8. Apparatus according to claim 6 characterized by said engageable means being out of the path of said moving means when said engaging means is in the third position.

9. Apparatus according to claim 5 characterized by resilient means urging said part-control means toward the path of said moving means.

10. Apparatus according to claim 5 characterized by resilient means urging said part-control means in a direction away from said guide means.

1]. Apparatus according to claim 10 characterized by resilient means urging said part-control means toward the path of said moving means.

12. Apparatus according to claim 5 characterized by said engageable means being movably carried by said part-control means, and resilient means yieldably retaining said engageable means in a fixed position relative to said part-control means.

13. Apparatus for handling parts comprising means forming a transfer station, a source of parts, guide means for feeding parts sequentially from said source to said transfer station, a member having engaging means for engaging parts along said guide means for temporarily moving those parts along said guide means in the opposite direction from which they are fed, said member having a position. in which said engaging means is clear of said guide means and a position in which said engaging means projects into said guide means, and said member having a third position in which said engaging means projects into said guide means and is in a position from the second position closer to the source of said parts.

14. Apparatus according to claim 1 characterized by second yieldably-mounted feet adjacent said first yieldably-mounted feet for aiding and retaining the next part in a position near the path.

15. Apparatus for handling parts comprising means forming a transfer station, a source of parts, guide means for feeding parts sequentially from said source to said transfer station, a member having engaging means for engaging parts along said guide means for temporarily moving those parts along said guide means in the opposite direction from which they are fed, said member having a position in which said engaging means is clear of said guide means and a position in which said engaging means projects into said guide means, means for moving the parts from said transfer station, and said member having means engagable by said moving means for moving said member from the position in which said engaging means is clear of said guide means to the second position in which said engaging means projects into said guide means.

16. Apparatus according to claim 15 characterized by resilient means urging said engageable means toward said moving means.

l7. Apparatus according to claim 16 characterized further by said engageable means being yieldably carried by said member.

18. Apparatus according to claim 15 characterized by resiliently-mounted feet for holding the parts in the path of said moving means.

19. Apparatus according to claim 18 characterized by additional resiliently-mounted feet for aiding in holding the next parts near the path of said moving means.

Claims

4. Apparatus for handling parts comprising means forming a transfer station, a source of parts, guide means for feeding parts sequentially from said source to said transfer station, a member having engaging means for engaging parts along said guide means for temporarily moving those parts along said guide means in the opposite direction from which they are fed, said member having a position in which said engaging means is clear of said guide means and a position in which said engaging means projects into said guide means, and resilient means urging said member to the position in which said engaging means is clear of said guide means.

7. Apparatus according to claim 6 characterized by said engageable means being in the path of said moving means when said engaging means is in the first and second positions.

11. Apparatus according to claim 10 characterized by resilient means urging said part-control means toward the path of said moving means.

13. Apparatus for handling parts comprising means forming a transfer station, a source of parts, guide means for feeding parts sequentially from said source to said transfer station, a member having engaging means for engaging parts along said guide means for temporarily moving those parts along said guide means in the opposite direction from which they are fed, said member having a position in which said engaging means is clear of said guide means and a position in which said engaging means projects into said guide means, and said member having a third position in which said engaging means projects into said guide means and is in a position from the second position closer to the source of said parts.

17. Apparatus according to claim 16 characterized further by said engageable means being yieldably carried by said member.