US3625570A

US3625570A - Apparatus for dispensing workpieces

Info

Publication number: US3625570A
Application number: US860754A
Authority: US
Inventors: Dennis Ford
Original assignee: CONCENTRIC PROD RES
Current assignee: CONCENTRIC PROD RES; CONCENTRIC PRODUCTION RESEARCH Ltd
Priority date: 1968-09-24
Filing date: 1969-09-24
Publication date: 1971-12-07
Anticipated expiration: 1988-12-07
Also published as: GB1281523A

Abstract

Apparatus for dispensing workpieces comprises a chamber incorporating opposed end closure assemblies one of which is provided with means for introducing into the chamber through a series of jet orifices air under pressure. Outlet means are located in the chamber at a point remote from the said one end closure assembly, and the chamber is provided with at least one normally closed opening through which workpieces are introduced into the chamber. Air issuing from the jet orifices creates a turbulence within the chamber which causes the workpieces to be directed away from the said one closure assembly and to be discharged individually at random through the outlet means under the influence of air escaping therethrough.

Description

United States Patent Jan. 18, 1969, Great Britain, No. 3,035/69 APPARATUS FOR DISPENSING WORKPIECES 10 Claims, 5 Drawing Figs.

US. Cl 302/2,

214/85 E, 221/1 Int. Cl B653 53/00 Field of Search 302/2;

Primary Examiner-Andres H. Nielsen Altorney-Scrivener. Parker, Scrivener and Clarke ABSTRACT: Apparatus for dispensing workpieces comprises a chamber incorporating opposed end closure assemblies one of which is provided with means for introducing into the chamber through a series of jet orifices air under pressure. Outlet means are located in the chamber at a point remote from the said one end closure assembly. and the chamber is provided with at least one normally closed opening through which workpieces are introduced into the chamber. Air issuing from the jet orifices creates a turbulence within the chamber which causes the workpieces to be directed away from the said one closure assembly and to be discharged individually at random through the outlet means under the influence of air escaping therethrough.

PATENTED DEC 7197! SHEET 2 BF 3 PATENTED nzc Hen SHEET 3 [)F 3 APPARATUS FOR DISPENSING WORKPIECES SPECIFIC DESCRIPTION This invention relates to a new or improved apparatus for dispensing workpieces, although the apparatus may also serve to separate, before dispensing, workpieces of the kind, such as coiled springs, which tend normally to become interengaged or entangled.

According to our invention apparatus for dispensing workpieces comprises a chamber incorporating opposed end closure members in one of which is provided means for introducing in the chamber through a series of jet orifices air under pressure, outlet means located in the chamber at a point remote from the said one closure member, and at least one normally closed opening permitting the introduction into the chamber of workpieces to be dispensed, the arrangement being such that air issuing from the jet orifices creates a turbulence within the chamber which causes the workpieces to be directed away from the said one closure member and to be discharged, one at a time at random, through said outlet means under the influence of air escaping therethrough.

In the chamber the workpieces are held in a state of semisuspension, which serves to separate the workpieces from each other when the workpieces are of the kind tending normally to become interengaged or entangled.

The chamber is arranged vertically with the said one closure member at its lowermost end, and the workpieces are directed upwardly towards and into contact with the said other closure member and are discharged, one at a time, through the outlet means.

The outlet means may comprise at least one outlet port located in the said other closure member, or in a port of a wall of the chamber adjacent to and slightly below the said other closure member. In a modification the outlet means comprises at least one flexible or rigid tube passing into the interior of the chamber through an opening in either the said other closure member, or in a part of a wall of the chamber adjacent to and slightly below the said other closure member, and into which the workpieces are drawn, one-by-one, due to the pres sure of the air escaping through the tube. The inner end of the tube may be flush with the inner surface of the wall of the chamber or it may project inwardly therefrom by a short distance.

Preferably the diameter of the inner end of the tube is greater than the maximum transverse dimension of the workpieces so that the workpieces are dispensed from the chamber in a precise attitude and in end to end relationship.

The free end of the pipe is positioned adjacent to or connected to means with which the workpieces are to be used, or in which they are to be stored.

For example-the free end of the pipe may be located at any convenient point in an assembly line so that the workpieces are delivered directly to a station at which they are required, and means may be incorporated at the free end of the pipe to control the rate at which the workpieces are dispensed from the pipe.

Alternatively the free end of the pipe may issue into a storage container, such as a helical tube, into which the workpieces are delivered substantially continuously and in end-toend abutting engagement.

One embodiment of our invention is illustrated in the accompanying drawings in which:

FIG. I is a section through apparatus for dispensing workpieces passing through the center line of the apparatus;

FIG. 2 is a section on an enlarged scale of a portion of the apparatus of FIG. I illustrating the means for introducing air under pressure into, and exhausting air from, the dispensing chamber of the apparatus;

FIG. 3 is a plan vie of the apparatus of FIG. 1 with certain parts omitted for clarity;

FIG. 4 is a plan view of a closure plate for the upper end of the chamber; and

FIG. 5 is a section through a pneumatically operated screwdriver incorporating means by which the screwdriver is supplied intermittently with screws from the apparatus.

The apparatus illustrated in FIGS. 1 to 4 of the drawings comprises a vertically disposed cylindrical body 10 comprising a lower transparent or translucent tube 11 clamped in sealing end-to-end engagement with an upper metal tube 12. The body is closed at opposite ends by a pair of end closure assemblies I13 and 14. The lowermost end closure assembly 113 comprises a pair of circular axially spaced mounting plates l3, 116 having opposed central spigots l7, 18 respectively secured in opposite ends of a tube 19 of substantial diameter. The

plates

13 and 16 are provided with aligned central openings through which is passed a tube 20 of relatively small diameter connected at its lowermost free end remote from the assembly to a supply of air under pressure through a union 2].

The

plates

15 and 16 are also provided with a pair of aligned openings offset radially with respect to the openings in which the tube 20 is received and in which are received opposite ends of a second tube 22 leading at its lower free end into a union 23 screwed into the plate 16.

The lowermost mounting plate 16 is adapted to be secured to a fixed structure, such as the working surface of a workbench, and the uppermost plate is detachably secured, by means of angularly spaced removable bolts 23a to the lower end of a frustoconical member 24 constructed from an alloy casting and of which the peripheral wall 25 diverges in an upward direction.

A circular orifice plate 26 with a series of orifices 27 and 28 spaced angularly on at least two pitch circles of constant diameters is located in an annular chamber 29 defined between opposed recesses in the mating faces of the frustoconical member 24 and the mounting plate 15 to which it is secured. The orifice plate is spaced above the adjacent face of the mounting plate 15 by an annular spacer member 30, and an annular resilient gasket 31 is interposed between the orifice plate 26 and the spacer member 30.

The spacer member 30 is provided with a central opening 31a providing communication between the upper end of the tube 20 and the orifices 27 and 28 through a chamber 32 defined between the lower face of the orifice plate 26 and the base of an annular recess 33 in the adjacent face of the spacer member 30.

The base of the recess in the plate 15 which defines a part of the chamber 29 is provided with an annular recess 34 with which communicates the upper end of the tube 22, and a radial passage 35 in the plate 15 provides communication between the recess 34 and a passage 36 in the wall 25 of the conical member 24.

A resilient annular gasket 37 is interposed between the lower end of the spacer member 30 and the adjacent upper faces of the plate 15 against which the spacer member 30 engages to ensure that the recess 34 is sealed from the chamber 32.

The uppermost end closure assembly 114 comprises a generally circular plate 38 provided with three openings 39 each of generally triangular outline which are equally spaced angularly on a pitch circle of constant diameter.

The plate 38 is provided with three equiangularly spaced radially extending cars 40 which seat against the upper surfaces of three complementary outwardly extending radial lugs 41 at the upper end of the metal tube 12. Each ear is provided with a circumferentially extending slot 42 of generally keyhole outline of which the circular portion is of a diameter slightly greater than that of a washer 43 interposed between the plate 38 and a nut 44 screwed into a threaded portion of a stud 45 screwed into a tapped hole in the lug 41 against which that ear is adapted to seat. Thus the plate 38 is detachably mounted on the upper end of the metal tube 12 by passing the nuts 44 and washer 43 through the circular portions of the slots 42 and then moving the plate 33 angularly so that the studs 45 are received in the portions of the slots 42 of lesser width and the washers 43 overlie and engage with the portions of the plate 38 on opposite sides of the slots 42.

An annular resilient gasket 46 forms a seal between the plate 38 and the upper end of a skirt 47 of reduced diameter projecting upwardly from the upper end of the metal tube 12.

The end closure assembly 14 is completed by the provision of a circular hopper 48 rotatably mounted on the plate 38 for relative movement thereto. The hopper 48 has in its base 48a a central opening 49 provided with a bush 50 having a radial flange 51 at its upper end. The flange 51 fon'ns an abutment for one end of a compression spring 52 urging the hopper into sealing engagement with the plate 38. The compression spring 52 is housed within a retainer 53 in engagement with a pair of nuts 54 screwed into the upper end of a bolt 55 which is passed through a central opening 56 in the plate 38 and through the bush 50.

The base 48a of the hopper 48 is formed with three openings 56a complementary to the openings 39 in the plate 38. The hopper 48 is rotatable relative to the plate 30 through an angular distance between a first loading position in which the complementary openings are superimposed, and a second position in which the openings 39 in the plate 38 are closed by parts of the base 48a of the hopper 48 between the openings 39.

In at least the second position, the hopper 48 is held positively against angular movement relative to the plate 38 by the engagement the inner end of a threaded bolt 57 through an axially extending threaded opening 58 in the wall of the hopper 48 with a recess 59 in the plate 38.

The metal tube 12 is provided in its peripheral wall with one or more ports of which only one is illustrated at 60. It is preferred that three equiangularly spaced ports 60 are provided but, according to the requirement of the apparatus, any convenient number may be provided. The port 60 is inclined upwardly with respect to the axis of the body 10. A union 61 having central bore 62 is secured in the port by means of thumb screw 63 having a threaded stem 64 screw through a threaded bore in a radial lug 65 integral with the metal tube 12 and engaging at its inner end in a recess 66 in the wall of the union 61. The wall of the union is provided with an inclined drilling 67 communicating with the bore 62 and directed towards the inner end the bore 62. The drilling 67 leads from a counterbore 68 in communication with the passage 36 in the wall 25 of the conical member 24 of the lowermost end closure assembly 13, through a communicating bore 69 in radial projections 70 integral with the walls of the

tubes

11 and 12. Where more than one union 61 is provided a corresponding number of separate passages 36 are provided, one connected to each union 61. A banjo union 71 provided with diametral passage 72 is located at the lower end of the tube 69.

A rigid tube 73 is secured in the or each union 61 at its inner end and at its outer end is connected to a flexible tube (not shown) leading to escapement means.

Normally communication between the chamber 32 in the closure assembly 24 and the interior of the cylindrical body through the orifices 27 is prevented by flexible annular flap valve 78 located in the chamber 32. The flap valve 78 is clamped at its radially innermost edge between the lower face of the orifice plate 26 and a nut and washer assembly 79 screwed on the lower end of a stem of a bolt 80 passing through an opening 81 at the center of the orifice plate.

In operation of the embodiment described above workpieces loaded into the hopper 48 are fed into a dispensing chamber defined by the interior of the tube 10, by rotating the hopper 48 into the first loading position relative to the plate 38. The hopper 48 is then restored to the second position in which it is held positively by engagement of the bolt 57 in the recess 59.

Alternatively the closure assembly 14 may be removed bodily from the dispensing chamber to enable workpieces to be loaded/unloaded directly into the tube 10. This is achieved by rotating the plate 38 and the hopper 48 with respect to the metal tube 12 in a direction such that the circular portions of the openings 42 in the plate 38 can be withdrawn past the washer 43.

Air under pressure is delivered to the chamber 32 below the orifice plate 26 through the central tube 20 and is discharged in the dispensing chamber through the orifices 28 from whence it issues through the bores 62 in the unions 61. The air jets impinge on the workpieces to hold them in a state of semisuspension, and the turbulence created in the dispensing chamber causes the workpieces to be urged upwardly and contact the plate 38 of the closure assembly 14 and the peripheral wall of the tube 10. The combination of turbulence and impact causes the workpieces to separate from each other and, when a workpiece is aligned with a bore 62 in a union 61 it escapes therethrough into the tube 73 and through which it travels due to the pressure of the escaping air. Thus the discharge of workpieces takes place in a random manner.

Should the pressure in the dispensing chamber exceed a predetermined value, such as could occur, if one or more of the outlet bores 62 in the unions 61, became blocked, the hopper rises automatically against the force in the spring 52 to allow the pressure in the chamber to be relieved.

Should a workpiece, for example a coiled spring, become wedged in an outlet bore 62, the supply of pressure air through the center tube 20 can be cutoff. Air can then be delivered to the annular recess 34 between the gasket 37 and the mounting plate 15 through the tube 22 from whence it passes to the drilling 67 in that union through the

passage

35 and 36 and the tube 69 to provide a blowback. Thus the dispensing chamber is subjected to air pressure acting in a opposite direction and thus pressure exhausts through the orifices 28 through the center tube 20. Under these conditions air also escapes to the center tube 20 through the orifices 27 since the flap valve 78 moves out of engagement with the orifice plate 26 when subjected to this back-pressure in the dispensing chamber.

Blowback at each outlet union 61 may take place one at a time in sequence. However, it is preferred that blowback at all unions 61 takes place simultaneously.

The application and cutoff of air under pressure through the center tube 20 and the subsequent application of air under pressure through the outer tube 22 is controlled by a sequence control unit incorporating a solenoid operated valve.

It is arranged that the drilling 67 in each outlet union is arranged sufficiently close to the inner end of the union to ensure that a maximum pressure is exerted on any component which may become wedged in the bore 62.

Depending upon the types of workpieces being dispensed by the apparatus, it may on occasions be necessary to alter or adjust the height of the dispensing chamber defined by the tube 10 to a value consistent with allowing the workpieces a suffi cient distance to orientate themselves with respect to the outlet bores 62.

This can be achieved by the insertion between the tube 10 and the end closure assembly 13, or between the tube 11 and the metal tube 12, one or more circular distance pieces.

in a modification the metal tube 12 may be omitted and the plate 38 is provided with three apertures (not shown) equally spaced on the pitch circle of constant diameter. The apertures in the plate 38 are aligned with complementary apertures in the base 48a of the hopper 48 connected to flexible tubes forming escapement means when the hopper 48 is in the second position. The apertures provide the outlet means from the chamber defined by the tube 11 for the workpieces. In this construction each passage 36 in the conical member 24 will be connected to one of the apertures in the base 480 of the hopper 48 through an external tube.

The construction and operation of this modification is otherwise as described above.

Means may be incorporated in the dispensing chamber for orientating headed workpieces so that they emerge from each escapement tube 73 in a desired attitude. These means comprises an assembly located in the outlet bore 62 in each union 61 which is constructed and arranged to provide the passage therethrough of a headed workpiece unless the workpiece is presented to the assembly transversely and with for example, the shank in advance of the head. Thus the head must be in advance of the shank, and the inner end of the bore 62 is cut away to provide a slot of dimensions consistent with those of the head. The base of the slot forms a stationary abutment with which the head engages directly and thereafter orientates the head workpiece into the correct attitude for subsequent passage through the escapement tube 73 in an end-to-end relationship with adjacent workpieces.

It is desirable that means are incorporated at the free end of each escapement tube 73 to control the rate at which the workpieces are dispensed from the dispensing chamber for delivering the workpieces at any stage in a production process as desired. The means can take various forms. In one example components such as screws or rivets having heads can be delivered directly to a pneumatically operated device, such as a screwdriver assembly or punch as illustrated in FIG. 5. The free end of the escapement tube 73 terminates in a fitting 90 inclined upwardly with respect to and located above a delivery guide tube 91 in which workpieces are supported on a column of air under pressure. The components are delivered to the fitting 90 after they have been orientated into attitudes with the stems in advance of the heads by an orientation device in the line between the tube 73 and the fitting 90. As the device is released, a sleeve 92 embodied in the device moves downwardly under the influence of a return spring 93 with respect to the screwdriver blade 94 to permit the column of air to be diverted. This allows the next workpiece to move, under the influence of air escaping from the dispensing chamber, into a position in an axially extending outlet guide tube 95 in which it can be acted upon by the blade 94. Simultaneously, this movement of the sleeve provides a signal for the next workpiece to be fed into a position previously assumed by the first. Thereafter the air pressure acting on the components is cut off.

lclaim:

1. Apparatus for dispensing workpieces comprising a chamber having opposite ends, first and second end closure assemblies closing said opposite ends of said chamber, a series of jet orifices provided in said first end closure assembly, means for introducing into said chamber through said jet orifices air under pressure, outlet means located in said chamber at a point remote from said first end closure assembly, and at least one normally closed opening through which workpieces to be dispensed are introduced into the chamber, the arrangement being such that air issuing from said jet orifices creates a turbulence within said chamber which causes the workpieces to be directed away from said first end closure assembly and to be discharged, one at a time at random, through said outlet means under the influence of air escaping therethrough, means being included for blowing air back down said outlet means for releasing a workpiece wedged therein,

2. Apparatus as claimed in claim 1, wherein said chamber is arranged vertically with said first end closure assembly at its lowermost end, whereby workpieces are directed upwardly towards said end closure assembly when said chamber is pressurized.

3. Apparatus as claimed in claim 1, wherein said outlet means comprises at least one outlet port located in a part of a wall of said chamber slightly below said second closure assembly.

4. Apparatus as claimed in claim 3, wherein a tube is secured to a union secured in said outlet port, and said union is provided with an axially extending through-bore through which workpieces are adapted to be dispensed from said chamber, and an inclined passage through which air can be blown back down said through-bore.

5. Apparatus as claimed in claim 1, wherein said first end closure assembly comprises a pair of complementary plates provided in their mating faces with a recess between which an orifice plate is clamped, and said orifice plate is provided on pitch circles of different diameters at least two series of jet orifices, both said series of orifices communicating with a second chamber defined between said orifice plate and a spacer interposed between said orifice plate and the lowermost plate of said first closure assembly, and a sealed recess between said spacer and said lowermost plate communicates with said outlet means, and wherein air for pressurizing said dispensing chamber passes into said dispensing chamber through said orifices from said second chamber which is in communication with a supply tube, and air under pressure from an inlet tube passes to said outlet means through said orifices, means being provided for supplying air through said tubes independently of each other.

6. Apparatus as claimed in claim 5, wherein said orifices on the pitch circle of smaller diameter are normally closed by a flap valve engageable with said orifice plate when said dispensing chamber is being pressurized through said orifices, and said flap valve is movable away from said dispensing chamber through said orifices on said pitch circle of smaller diameter when said dispensing chamber is subjected to pressure from said inlet tube.

7. Apparatus for dispensing workpieces comprising a chamber having opposite ends, first and second end closure assemblies closing said opposite ends of said chamber, a series of jet orifices provided in said first end closure assembly, means for introducing into said chamber through said jet orifice air under pressure, outlet means located in said chamber at a point remote from said first end closure assembly, and at least one normally closed opening through which workpieces to be dispensed are introduced into the chamber, the arrangement being such that air issuing from said jet orifices creates a turbulence within said chamber which causes the workpieces to be directed away from said first end closure assembly and to be discharged, one at a time at random, through said outlet means under the influence of air escaping therethrough, wherein said second end closure assembly comprises a plate member in sealing engagement with an adjacent end of a wall defining said dispensing chamber, and a hopper member mounted on said plate member for relative rotational movement between a first loading position in which complementary openings in the hopper member and the plate member are aligned and a second position in which the openings in one member are closed by parts between the openings in the other member.

8. Apparatus as claimed in claim 7, wherein said chamber is arranged vertically with said first end closure assembly at its lowermost end and at least a portion of said chamber terminating at said second end closure assembly comprises a metal tube provided with at least one outlet port which is inclined upwardly with respect to the axis of the chamber and in which an outlet union is located.

9. Apparatus as claimed in claim 7, wherein said plate member and the hopper member are normally spring urged into sealing engagement with each other, and are automatically moved away from each other against the spring loading to relieve the pressure in said dispensing chamber when that pressure exceeds a predetermined value.

10. Apparatus as claimed in claim 7, wherein said plate member is detachably mounted on said wall of said dispensing chamber and is removable therefrom by a rotational movement followed by an axial movement.

Claims

1. Apparatus for dispensing workpieces comprising a chamber having opposite ends, first and second end closure assemblies closing said opposite ends of said chamber, a series of jet orifices provided in said first end closure assembly, means for introducing into said chamber through said jet orifices air under pressure, outlet means loCated in said chamber at a point remote from said first end closure assembly, and at least one normally closed opening through which workpieces to be dispensed are introduced into the chamber, the arrangement being such that air issuing from said jet orifices creates a turbulence within said chamber which causes the workpieces to be directed away from said first end closure assembly and to be discharged, one at a time at random, through said outlet means under the influence of air escaping therethrough, means being included for blowing air back down said outlet means for releasing a workpiece wedged therein.