US 3563361 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
' I United States Patent H 13,563,361
 Inventor Miroslav J. Plroutek 3,069,049 12/1962 Brown 221/171 Stamford, Conn. 3,143,201 8/1964 Wyle et al 198/33(R4)  Appl. No. 734,463 3,194,389 7/1965 Grgetic 198/209  Filed June 4,1968 3,367,015 2/1968 Brosene, Jr 29/212  Patented Feb. 16, 1971  Assignee Self-Matic Valves Corporation W Stamford, Conn. Assistant Exammer--Douglas D. Watts Attorney- Blair, St. Onge & Mayers  SETSCREW FEEDING, ORIENTINQ AND DRIVING SYSTEM 3 Claims, 11 Drawing Figs.
 US. ("I 198/33;
29/240 ABSTRACT: The disclosed system includes a vibratory feeder [5i] III. C] B658 feeding headless set crews successivelly to an orienting p-  Fit O'SCII'CII 29/21 I, paratus, which usgs an air jet properly orient the et screws 208, 212, 211D, 0 l98/33(Rl 33( Z), or has a passageway admitting only properly oriented set 193/ 3, 3(1)) screws. An escapement mechanism in a delivery of set screws with o eration of a shuttle mechanism in ositionin each to  References cued be driv en into a part by a driver mechanisiir. This m chanism UNITED STATES PATENTS includes an air cylinder and piston for reciprocating a rotating 2,904,162 9/1959 Simer 198133 driver element engaging each set screw.
Patentd eb; 16, 1971 4 Sheets-Shee t 4 SETSCREW FEEDING, ORIENTING AND DRIVING SYSTEM BACKGROUND AND OBJECT OF THE INVENTION Headless set screws, because of their configuration, present special automated handling problems. In those automated situations where set screws are being fed to a set screw driver, it is of paramount importance that the set screws be properly oriented in order that they may be driven into the threaded bore of one part which is to be affixed to another. If the set screws are not properly oriented, attempts to drive the set screw invariably causes jamming of the system and possible damage thereto. In either case, the feeding and driving system must be shut down in order to remedy the situation caused by an improperly oriented set screw. It will be appreciated that any shutdowns of the set screw handling system are costly inasmuch as it necessitates corresponding shutdowns of the manufacturing and assembly operations to which the system is adapted.
Systems for orienting, feeding and driving headless set screws are known in the art. However,-such prior art systems are typically complex in design and therefore quite expensive. Moreover, many such prior art systems cannot handle set screws of conventional design, but rather require a specially designed set screw as a basis for effective operation.
It is accordingly an object of the present invention to provide an orienting, feeding and driving system for conventional headless set screws which is simplified in design, inexpensive to manufacture, and reliable in operation.
SUMMARY OF THE INVENTION In accordance with the above noted general object of the invention, there is provided a system for properly orienting conventional headless set screws and successively feeding them to a set screw, driver mechanism which, in turn, drives the set screws into the threaded bores of successive parts to be assembled. The set screws are contained in the bowl or hopper of a "conventional vibratory feeder. Vibration of the feeder causes the set screws to proceed in trainlike fashion to a point of delivery at which is positioned one of two orienting apparatus constructed according to the invention depending upon the size of the set screws being handled.
In one form, the orienting apparatus utilizes an air jet which permits passage of those set screws coming tip first but flips over those set screws coming socket end first. The air jet is so oriented that it impinges against the sidewall of the set screw socket recess from a downward direction, causing the set screw to flip over to assume the desired tip first orientation. This form of orienting apparatus handles set screws whose lengths are equal to or in excess of their diameters. The properly oriented set screws then proceed through a delivery tube to a shuttle mechanism.
In the other form of orienting apparatus designed to handle set screws whose lengths are less than their diameters, there is provided a passageway having a cross section conformed such as to permit the passage therethrough of only those set screws having the desired orientation. All improperly oriented set screws arriving at the orienting apparatus cannot enter the passageway and fall back into the feeder bowl. There is further included elements which are caused to vibrate by the vibratory feeder and are in communication with a bore constituting the approach into the delivery tube. These elements impart agitation to the set screws as they are routed from the passageway into the delivery tube, thereby preventing jamming of the set screws thereat.
An escapement mechanism incorporated in the delivery tube beyond the orienting apparatus operates to coordinate the delivery of the set screws to the shuttle mechanism in accordance with the operation of the shuttle mechanism and the operation of the set screw driver mechanism. The escapement mechanism further includes an air jet for insuring positive and speedy delivery of each set screw to the shuttle mechanism.
The shuttle mechanism includes a shuttle element adapted to assume one position where it accepts a set screw from the delivery tube and moves to a second position wherein the set screw is positioned in alignment with a driver element of the set screw driver mechanism. The shuttle mechanism is further adapted to mount an elastic sheetlike member having an aperture through which the set screw is advanced on the tip of the driver element. The aperture of the elastic member is less than the diameter of the set screw so as to impart some resistance to the advancement of the set screw thus insuring full and positive engagement of the tip of the driver element in the socket recess of the set screw. In addition, the shuttle mechanism mounts a sensor adapted to sense the act of removal of the set screw from the shuttle element by the driver element.
A chamber in the shuttle element-accommodating each set screw is provided with a lengthwise slot allowing the driver element to clear the shuttle chamber as the shuttle element is returned to the position for acceptance of the next set screw. Thus, the shuttle element need not wait for a retraction of the set screw driver element from the shuttle chamber.
The set screw driver mechanism includes a motor for imparting rotational motion to the set screw driver element. The motor output shaft is drivingly connected to a shaft adapted for both rotational and reciprocal motion by virtue of a sliding coupling. This shaft carries a piston operating in a cylinder. The piston is affixed to the shaft such as to prevent relative axial movement while permitting relative rotational movement therebetween. Air under pressure: is introduced into the cylinder on opposite sides of the piston to cause reciprocation of the shaft. The output end of this shaft mounts a self-aligning slip clutch in which the rearward end of the set screw driver element is secured. This slip clutch includes a flexible disc which is drivingly connected at its center to the set screw driver element and is somewhat loosely clamped at its periphery between elements drivingly connected to the reciprocating shaft. The flexible disc accommodates possible misalignment of the reciprocating shaft and the set screw driver element and is also adapted to slip between its clamping elements when the set screw is driven tightly into a part.
The invention accordingly comprises the features of construction, combinations of elements, and arrangement of parts which will be exemplified in the constructions hereinafter set forth, and the scope of the invention will be indicated in the claims.
For a fuller understanding of the nature and objects of the invention, reference should be had to the following detailed description taken in connection with the accompanying drawings, in which:
FIG. I is a perspective view of the overall system constructed according to one embodiment of the invention;
FIG. 2 is an enlarged cross-sectional view, taken along line 2-2 of FIG. I, of an orienting apparatus employed in the system of FIG. 1, illustrating its operation in passing properly oriented set screws;
FIG. 3 is an enlarged cross-sectional view, taken along line 2-2 of FIG. I, of the orienting apparatus of FIGS. 1 and 2 illustrating its operation in flipping over improperly oriented set screws;
FIG. 4 is an enlarged sectional view, taken along line 4-4 of FIG. I, of the escapement mechanism employed in the system of FIG. 1;
FIG. 5 is a top plan view, partiallly broken away, of a modified orienting apparatus for use in the system of FIG. 1',
FIG. 6 is a sectional view taken along line 6-6 of FIG. 5;
FIG. 7 is a sectional view taken along line 77 of FIG. 6;
FIG. 8 is a top plan view, partially broken away, of the set screw driver and shuttle mechanisms employed in the system of FIG. 1;
FIG. 9 is a sectional view taken along line 9-9 of FIG. 8;
FIG. 10 is a sectional view taken along line 10-10 of FIG. 9; and
FIG. 11 is a top plan view of the shuttle mechanism of FIG. 8 illustrating its operation in conjunction with that of the set screw driver mechanism.
Similar reference numerals refer to like parts throughout the several views of the drawings.
DETAILED DESCRIPTION OF THE INVENTION The headless set screw orienting feeding and driving system, constructed according to one embodiment of the invention seen in FIG. I, includes a vibratory feeder, generally indicated at 10, having a hopper or bowl 12, containing a plurality of set screws 14. The vibratory feeder 10 is of conventional design including a motor (not shown) for suitable vibrating the bowl 12 to cause the set screws 14 to progress up a spiral ramp 16 formed along the inner sidewall of the bowl. The set screws 14 move in single file up the ramp 16, ultimately arriving at an orienting apparatus, generally indicated at 18, which is affixed to the sidewall of bowl 12 at the upper termination or exit of ramp l6.
The orienting apparatus 18 of FIG. 1, shown in enlarged scale in FIGS. 2 and 3, is designed to handle those set screws having a length dimension at least equal to its diameter dimension. It will be appreciated that set screws having this dimensional characteristic will progress up the ramp 16 and arrive at the orienting apparatus 18 while lying on their side. For those rare instances when a set screw 14 progresses up the ramp 16 standing on one end, a gate (not shown) may be provided to project inwardly from the sidewall of the bowl and spaced above the floor of ramp 16 by distance greater than the set screw diameter for deflecting up-ended set screws off the ramp.
Consequently, all set screws arriving at the orienting apparatus 18 are lying on their sides. The problem remains, however, to properly orient the set screws such that they are delivered to the remainder of the system with the appropriate end first. As will be seen from the illustrated embodiment of the invention, the set screws must be delivered tip end first.
Still referring to FIG. 1, just in front of the orienting apparatus 18, a deflector strip 20 is positioned to project partially across the exit of ramp 16. This is commonly done in the vibratory feeder art to provide what is termed a pressure break" for creating spacing between successive set screws. A screw 21 is provided for adjustment of degree of projection of the deflector relative to the ramp exit. Prior to reaching the deflector 20, the set screws are generally in end-to-end contact such that the set screws are being pushed from the rear by succeeding set screws. A separation between set screws provided by deflector 20 prevents the movement of each set screw therebeyond from being influenced or encumbered by its successor.
The orienting apparatus 18, as seen in FIGS. 1 through 3, consists ofa block 22 which is affixed to the feeder bowl 12 by suitable means such as bolts (not shown) beyond the exit of ramp 16. A shallow horizontal groove 24 formed in the upper surface of block 22 extends generally horizontally to its termination where it opens into a vertically oriented bore 26 (best seen in FIGS. 2 and 3). The lower end of bore 26 is countersunk for receipt of the upper end of a delivery tube 28. A bushing 29 (FIG. 2) is accommodated in this counterbore above the upper end of the delivery tube 28. Since the orienting apparatus 22 is fixedly connected to the feeder bowl 12, it is vibrated with the feeder bowl and the bushing 29 vibrates within this counterbore. The provision of vibrating bushing 29 is to insure that the set screws 14 make the transition from the bore 26 to the delivery tube 28 without jamming.
The portion of the block 22 along the inner side of the groove 24 is machined down to form a ramp surface 30 sloping towards the groove 24. The set screws are diverted by the deflector 20 from the ramp 16 out onto the ramp 30 from which they roll into groove 24. In order to orient the set screws 14, in accordance with the present invention air under pressure is supplied through a hose 32 which is secured in a bore 34 drilled in the block 22. The bore 34 communicates with a hole 36 drilled at an angle through the sidewall of bore 26 at a point opposite from the exit of groove 24. As a consequence, a jet of air is directed generally upwardly at the leading end of the set screws as they move along groove 24 approaching the bore 26.
The set screws 14, as seen in FIG. 2 are formed in conventional fashion having a frustoconically shaped tip 38 at one end and hexagonal socket recess 40 at its other end. It will be appreciated that the set screws may also have pointed tips. If a set screw 14 in groove 24 approaches bore 26 tip end first, the jet of air is so directed that it largely misses the reduced diameter tipped end of the set screw, thus permitting the set screw to make the transition from the horizontal groove 24 to the vertical bore 26. On the other hand, as seen in FIG. 3, if a set screw in groove 24 approaches bore 26 socket end first, the jet of air emanating from hole 36 enters the socket recess 40 and impinges against the upper sidewall portion thereof. This produces an upward force on the socket end of the set screw 14, causing the set screw to be flipped over end for end, such that the set screw becomes oriented tip end first in the groove 24.
It is thus seen that the provision of the air jet in the orienting apparatus 18 of FIGS. 1 through 3 permits the passage of set screws 14 tip end first and reorients those set screws which arrive socket end first.
As previously noted, the orienting apparatus 18 of FIGS. I through 3 is specifically adapted to handle set screws whose lengths equal or exceed their diameters. The orienting apparatus of FIGS. 5 through 7, generally indicated at 18', is especially adapted to handle set screws whose lengths are less than their diameters. Thus, in the system shown in FIG. 1, the orienting apparatus 18' is substituted for the orienting apparatus 18 when the set screws to be handled have a length dimension which is less than its diameter. The orienting apparatus 18 is thus secured to the feeder bowl 12 beyond the termination of ramp 16. As seen in FIGS. 5 through 7, the orienting apparatus 18' includes an apron surface 46 which constitutes an extension of the feeder ramp 16. The apron surface is bounded on one side by a curved wall 48 which guides the set screws 14 to the entrance of a groove 50.
As best seen in FIG. 7, the groove 50 is formed having vertical upper sidewalls 50a and inwardly tapered lower sidewalls 50b which merge into a flat bottom surface 50c. The top of groove 50 is closed off with a plate 52, secured in place by screws 51. The groove 50 when covered by plate 52 constitutes an enclosed passageway which, as seen in FIG. 7, has an entrance cross section such as to admit set screws 14 only if they are standing on their tipped end. If a set screw at the entrance ofthe groove 50 is standing on its socket end, it cannot enter due to interference with the sloping sidewalls 50b thereof. Since the improperly oriented set screws 14 cannot enter into the passageway formed by groove 50 and cover plate 52, they are pushed passed the entrance thereto by succeeding set screws. These rejected set screws move up a ramp surface 46a to an elevated apron surface 46b from which they drop back into the feeder bowl. The ramp apron surface 460 is provided so as to prevent properly oriented set screws from moving too rapidly as they pass the entrance to the passageway. Instead, the ramp 46a causes them to dwell momentarily at the entrance to the passageway, giving them every opportunity of entry therein. a
At this point, it should be pointed out that the vast majority of set screws 14 inherently arrive at the orienting apparatus 18 properly oriented, that is, standing on their tipped ends. This is due to the fact that the tipped end 38 is heavier than the socket end due to the removal of material in forming the socket recess 40. Thus, since the center of gravity of an individual set screw whose length is less than its diameter is nearer its tipped end than its socket end, it will in most cases orient itself tip down in response to vibratory motion of the feeder 10.
Still referring to FIGS. 5 through 7, the set screws 14 progress through the passageway (groove 50) to the end thereof which opens into a vertical bore 52. Surrounding the upper end of bore 52 are a series of three wells 54 which loosely receive pins 56. The wells 54 are so positioned that they open into the sidewall of bore 52. Consequently, the pins 56 in wells 54 protrude somewhat into the bore 52. The upper end portion of each pin 56 is neck down to form an annular groove 56a. A keeper plate 58, held in place by screws 59 projects into each of the grooves 56a of the pins 56 to retain them in their respective wells 54.
As the feeder is vibrated, the pins 56 also vibrate, thus maintaining the set screws agitated as they make the transition from the groove 50 to the vertical bore 52. This completely eliminates the possibility of the set screws jamming at this point. Also, as seen in FIG. 6, the feature of the loose bushing 29 described in connection with FIG. 2, is also preferably incorporated in the orienting apparatus 18'. The vibratory motion of the bushing 29 insures that .the set screws safely make the transition from the vertical bore 52 to the delivery tube 28.
To further assist the set screws 14 in making the transition from groove 50 to vertical bore 52, an extremely flexible spring strip 60, seen in FIG. 6, is angularly mounted at one end in a standard 61 so as to orient a horizontally extending freeend portion 60a vertically above bore 52. The set screws 14 are engaged by the free-end 60a of spring 60 as they move from groove 50 out into bore 52. Spring 60 thus serves to maintain the set screws in a generally upright orientation during this transition and also imparts a small downward thrust to the set screws as they become free to fall through bore 52.
Returning now to FIG. 1, the appropriately oriented set screws 14 passed by orienting apparatus 18 or 18' fall through the upper vertical portion of the delivery tube 28 to an escape ment mechanism, more clearly seen in FIG. 4, operates to permit coordination of the delivery of the set screws through the remaining portion the delivery tube 28 with the operation of a shuttle mechanism, generally indicated at 66, and the iemainder of the system to be described. Thus, as seen in FIG. 4, the set screws 14 fall under gravity through the vertical portion of the delivery tube 28 to a point where they are stopped by a pin 68 which projects through a longitudinal slot 70 in the delivery tube. Pin 68 is carriedby an elongated spring 72 at a point spaced inwardly from the free end thereof. The other end of spring 72 is secured by a screw 75 to a bracket 74 carried by the tube 28. Preferably, the screw 75 passes through an elongated slot 75' (FIG. I) in the spring 72 to provide for convenient adjustment of the vertical position of the pin 68. A depending flange 76 mounted to bracket 74 supports an air cylinder 78 adjacent its lower end. The air cylinder 78 contains a piston (not shown) which is caused to reciprocate by the appropriate application of air under pressure through hose 78'. The piston of air cylinder 78 carries a pin 80 which is adapted to project through aperture 80' in one side and slot 70 in the other side of delivery tube 28, and thus across the bore thereof.
As seen in FIG. 4, the set screws in delivery tube 28 stack up against pin 68. The piston of air cylinder 78 is spring biased to the left, as seen in FIG. 4, and pin 80 is retracted from delivery tube 28. Air is then introduced through hose 78 driving the piston to the right. The pin 80 connected thereto moves through aperture 80 and slot 70 in the delivery tube and engages the free end of spring 72, deflecting it to the right as seen in phantom. This withdraws pin 68 and the bottom one of the stacked set screws is freed to fall to the position shown in phantom where it engages pin 80. The rest of the set screws drop down a corresponding amount until they rest on the bottom most set screw. The pressure of the air communicated through hose 78' is terminated and pin 80 retracts from tube 28. The bottom most set screw falls beyond the position of pin 80 while spring 72 returns to its normal position with pin 68 engaging and stopping the next lower screw 14 and those stacked above it.
The single set screw released by each operation of the escapement mechanism 64 falls downwardly in the delivery tube 28 to the point where the tube bends to a generally horizontal orientation leading to the shuttle mechanism 66. In order to insure delivery of the set screw through the horizontal section of the delivery tube 28, a jet of air is supplied through a hose 82 communicating with a port 84 formed in the delivery tube at the upper portion of the bend. This jet of air blows against each set screw 14 released by the escapement mechanism 64 and forces it through the horizontal section of the delivery tube 28 and into the shuttle mechanism 66.
The shuttle mechanism 66, seen in FIGS. 1 and 8 through 11, includes a shuttle 92 adapted for reciprocating movement in a guide block 93 including a floor 94, a sidewall 96, and an end wall 98. A plate closes off the other side of the guide block while a plate 102 closes off the other end to thus define a track accommodating reciprocating movement of the shuttle element 92. End wall 98 limits movement of the shuttle 92 in one direction while the vertical wall of a ledge 103 limits movement in the opposite direction. The plate 102 mounts an air cylinder 104 into which air under pressure is introduced through hose 106. The piston in air cylinder 104 is normally spring biased to a rearward position and it is forced to forward position under air pressure. An arm 108 is connected at one end to the piston and at its other end to the shuttle 92. Thus, operation of the air cylinder 104 causes reciprocating movement of the shuttle 92.
The shuttle 92, best seen in FIGS. 8 through 11, is in the form of a block having a bore drilled therethrough to provide a chamber 110 in which the set screws are carried. An elongated slot 112 (FIG. 1, 9 and 10) is formed in the shuttle 92 opening the chamber 110 to the face of the shuttle facing the air cylinder 104. When the shuttle 92 is in the position shown in FIGS. 1 and 8, its chamber 110 is aligned with the exit end of the delivery tube 28 which is fitted in an aperture 114 in sidewall 96. Thus, each set screw released by the escapement mechanism 64 is blown through the horizontal section of the delivery tube and into the chamber 110* ofthe shuttle element. The other end of the chamber 110 is blanked off by the sidewall 100. After a set screw has been delivered into chamber 110, the supply of pressurized air through hose 106 is discontinued, and the piston returns to its rearward position bringing with it the shuttle 92. The shuttle chamber 110 is thus brought into alignment with an aperture 118 in sidewall 96 into which extends the driver element 120 ofa set screw driver mechanism, generally indicated at 122 (FIGS. 1 and 8). Also, the shuttle chamber 110, when the shuttle 92 is in the position shown in FIG. 11, is aligned with an aperture 124 in plate 100 and the threaded bore 126 of a part 127 which is to threadingly receive the set screw 14. The part is one of a succession sequenced into position on a turntable 128 or other suitable automated handling mechanism.
As will be seen, the driver element 120, while being rotated, is also advanced to the right as seen in FIGS. 1 and 8. The hexagonal tip of the driver element 120 enters into the socket recess 40 of the set screw and it is pushed out of chamber 110 through aperture 124 in plate 100 and threaded into bore 126 of the part 127 by extension and rotation of the driver element. It is to be noted that by virtue of the longitudinal slot 112 opening into the shuttle chamber 110, the shuttle 92 may be returned to the position shown in FIG. 8 while the extended set screw driver element 120 is still engaged in the act of threading a set screw into bore 126. The slot 112 permits the driver element to clear the chamber 110 as the shuttle is moved away. Since the shuttle does not have to wait for retraction of the driver element 120 before returning to its other position for accepting the next set screw, a significant economy in time is realized.
In order to insure that the hexagonal tip of the driving element 120 is in full and positive engagement with the hexagonal socket recess 40 in the set screws 14, the aperture 124 in plate 100 is bounded by an apertured elastic sheet of polyurethane, or the like, accommodated in a recess 129 in plate 100 and adjustably compressed by a second apertured plate 101. The clamping pressure of plate 101 is adjusted by tightening or loosening screws 105 threaded into plate 100. The size of the aperture in elastic sheet 130 is made less than the diameter of the set screw but greater than the diameter of the driver element 120 by adjustment of the clamping pressure 1 exerted by plate 101. The apertured sheet 130 thus provides a measure of resistance to the passage of the set screw therethrough as it is pushed by the driver element. This resistance insures that the hexagonal tip of the driver element 120 is fully seated in the socket recess 40 of the set screw.
Positioned above the aperture 124 in plate 100 is a sensor 134 which includes an elongated spring 135 clamped at its upper end between a bracket 136 and plate 101. The spring 135 is mounted such that it extends downwardly in contiguous relation to the depending portion of the bracket 136. The free end of spring 135 extends beyond bracket 136 to a point where it is engaged by the set screw as it is driven from the shuttle mechanism 66 into the part 127. The midportion of spring 135 is closely spaced to the open end of a hose 140 carried by the depending portion of bracket 136. The other end of hose 140 is connected to source of ,air supplied under low pressure. The spring 135 is deflected by'engagement with a set screw driven from shuttle chamber 110, closing off the open end of hose 140 and causing a pressure rise which is sensed by a pilot valve (not shown). The pilot valve responses thereto to initiate the next cycle of the system. Specifically, this entails actuation of the air cylinder 104 returning the shuttle 92 to its other position and also actuation of air cylinder 78 causing operation of escapement 64 and delivery of the next set screw into shuttle chamber 110.
The set screw driver mechanism 122, as best seen in FIGS. 1 and 8, includes an electric motor 150 which provides the rotational force for turning the driver element 120. The output shaft 151 of the motor mounts a'plate 152 which rotates therewith. The plate 152 mounts a pair of guide pins 153 which extend parallel to the motor output shaft but laterally offset therefrom. The guide pins 153 are slidingly received in a pair of apertures formed in a disc 154 which is keyed on the end of a shaft 156 extending coaxially with the motor output shaft 151. The disc 154 may be of a somewhat flexible nature so as to accommodate slight misalignment between the axis of motor output shaft 151 and shaft 156.
It is seen that by virtue of plate 152, disc 154 and interconnecting guide pins 153, rotation of the motor output shaft 151 is transmitted to shaft 156. This rotational coupling is maintained while shaft 156 and disc 154 reciprocates coaxially relative to motor output shaft 151 and plate 152. Disc 154 merely slides along the length of the guide pins 153, with the guide pins preserving the rotational coupling.
Still referring to FIGS. 1 and 8, to reciprocate shaft 156 there is provided an air cylinder block 160. A horizontal cylinder 162 is bored through the cylinder block 160. The cylinder 162 is closed off by end plates 164 having e central apertures accommodating shaft 156 as it extends coaxially through cylinder 162. Suitable sealing means (not shown) about the central apertures in plates 164 prevent the escapage of air.
A piston 170 is carried on the portion of shaft 156 within the cylinder 162. Snap rings 172. accommodated in annular grooves in the shaft 156 constrain the piston 170 from axial movement relative to the shaft. A pair of washers 174 are interposed between each snap ring and the piston. An O-ring 176 accommodated in a peripheral groove 178 in the outer surface of the piston 170 prevents the leakage of air past the gap between the outer surface ofthe piston and the wall of the cylinder 162. Thus, the dimensional tolerances of the piston and cylinder are not critical.
It is seen that if air under pressure is forced into the cylinder 162 through fluid connection 180 to the left of piston 170, the piston together with shaft 156 is driven to the right as seen in FIG. 8. Conversely, if air under pressure is introduced to cylinder 162 through fluid connection l82 to the ri ht of the piston 170,1t1s driven to the left bringing with it the s aft 156.
Shaft 156 is therefore reciprocated and at the same time is permitted to rotate by virtue of the construction of the air cylinder and piston. It is seen that while the axial position of the piston 170 relative to shaft 156 is fixed, relative rotational therebetween is permitted. Consequently, shaft 156 rotates relative to piston 170 while it is being reciprocated by the piston. Inasmuch as the piston 170 is not forced to rotate with the shaft 156, the useful life of the O-ring is significantly increased.
The right hand of reciprocating shaft 156 is drivingly connected to driver element 120 through a suitable coupling 184. Thus, rotation and reciprocation of the former is imparted to the latter pursuant to driving a set screw 14 from shuttle chamber and threading it into the bore 126 ofa part 127.
It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above constructions without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention which, as a matter of language, might be said to fall therebetween.
1. 'Orienting apparatus for use in conjunction with vibrator feeders handling headless set screws having lengths less than their diameters, and first and second distinctly different end configurations, said apparatus comprising, in combination:
A. a body secured to the feeder adjacent the feeder output to which the set screws propagate B. means forming an apron surface on said body over which move the set screws from the feeder output;
C. means forming a generally horizontal passageway in said body, 1. said passageway having an exit end and an en trance of a cross section adapted to admit only those set screws standing on their first ends;
D. a wall carried by said body for guiding the set screws over said apron surface to said passageway entrance;
E. means forming a generally vertical bore in said body, said bore having 1; an upper end open to said exit end of said passageway;
F. means forming at least one well in said body adjacent said bore upper end, each said well 1. being open to said bore; and
G. an element loosely received in each said well, said element 1. extending partially into said bore, and 2. vibrating in response to vibration of the feeder to agitate the set screws making the transition from said passageway to said bore, thereby preventing jamming.
2. The orienting apparatus defined in claim 1 which further includes; A. a resilient element secured at one end above said body and having a horizontally extending free end portion disposed above said bore, 1. said free end portion engaging the set screws and imparting a downward thrust to the set screws.
3. The orienting apparatus defined in claim 1 which further includes: A. an inclined surface on said body beyond said passageway entrance from said wall.