US3827367A

US3827367A - Conveyor trolley with camming heads

Info

Publication number: US3827367A
Application number: US00309672A
Authority: US
Inventors: M Paglia
Original assignee: Individual
Current assignee: Individual
Priority date: 1972-11-27
Filing date: 1972-11-27
Publication date: 1974-08-06
Anticipated expiration: 1991-08-06

Abstract

An improved conveyor trolley system of the type in which a series of load-carrying trolleys are supported in rolling suspension from an overhead monorail track, and are moved by pushing engagement between successive trolleys. The invention resides in the combination of a track with predetermined curvature range, trolleys of predetermined maximum length, and leading and trailing camming means on each trolley to insure smooth pushing engagement when a trolley series of the specific type is moved on a track of the specified type. One preferred species includes a skirt cam for inhibiting derailment of the trolley when traveling on a track of the specified type. Another preferred species provides the cam surfaces in a unitary formed sheet metal body incorporated in each trolley head assembly.

Description

United States Patent 91 Paglia 1 CONVEYOR TROLLEY WITH CAMMING HEADS [76] Inventor: Marius F. Paglia, 2913 Westbrook Ave., Hollywood, Calif. 90046 [22] Filed: Nov. 27, 1972 [21] Appl. No.: 309,672

[52] US. Cl. 104/93, 105/150 [51] Int. Cl EOlb 25/22 [58] Field of Search 105/148, 150, 152, 156;

[56] References Cited UNITED STATES PATENTS 2/1953 Finkbeiner 105/150 6/1971 Weiss 105/152 l/l972 Kavieff 104/172 8.]

Primary Examiner-M. Henson Woods, Jr. Assistant Examiner-D. W. Keen Attorney, Agent, or Firm-Edmond F Shanahan Aug. 6, 1974 5 7 ABSTRACT An improved conveyor trolley system of the type in which a series of load-carrying trolleys are supported in rolling suspension from an overhead monorail track, and are moved by pushing engagement between successive trolleys. The invention resides in the combination of a track with predetermined curvature range, trolleys of predetermined maximum length, and leading and trailing camming means on each trolley to insure smooth pushing engagement when a trolley series of the specific type is moved on a track of the specified type.

One preferred species includes a skirt cam for inhibiting derailment of the trolley when traveling on a I track of the specified type.

Another preferred species provides the cam surfaces in a unitary formed sheet metal body incorporated in each trolley head assembly.

6 Claims, 8 Drawing Figures CONVEYOR TROLLEY WITH CAMMING HEADS SPECIFICATION This invention relates generally to conveyor trolleys of the type in which a series of load-carrying trolleys, hanging in rolling suspension from an overhead monorail track, are moved by end-to-end pushing engage ment, and/or power projection. Such trolleys are used in many factory and warehouse applications, but they have achieved particularly widespread use in garment warehouses because of their cleanliness, lack of fire hazard, and general usefulness in carrying light and medium loads.

Moreover, such trolleys have been successfully adapted to an economic system of automation particularly suited for garment handling. In the automation system, the track has main and branch lines. Switching means capable of automatic or manual actuation are located at turn-off points for each branch. Trolleys may also be provided with switch actuating means which may be selectively set to divert that trolley into any one of many predetermined branch tracks. The person operating the conveyor trolley system may load an individual trolley with a specified assortment of garments which it is desired to divert to a designated branch; he may then set the switch actuating means on that trolley so that it will be automatically diverted from the main track to the destination branch track, as it is pushed along by means of power, in a series of individual trolleys.

In a typical installation of a conveyor trolley system of the type described, the warehouses are huge, and are operated by a relatively small crew of operating personnel, who are stationed at various work locations. The utility and economy of such an installation is lost if the conveyor line is frequently brought to a standstill by jamming at some point in the track remote from an operator's station.

Unfortunately, the utility and economy of such conveyor installations has been much impaired by tendencies of the trolleys to be derailed by the pushing force, particularly when a long series of trolleys must be pushed along a track with many curves and inclines. The problems of trolley derailmenthave arisen with new difficulties in each new installation. Generally, each new installation has required track confirgurations not found in prior installations, so that experience could not be relied upon to assure satisfactory operation of a newly designed conveyor trolley system. On the contrary, movers have had to resign themselves to building the system and then debugging it after its particular jamming problems were developed during initial operation.

It is the primary object of this invention to provide a novel combination of track and trolley with much greater resistance to derailment, than in previously known pusher type conveyor trolley systems, and moreover to achieve the superior features described herein after by means of a construction lower in cost than previously known conveyor trolley systems.

A second object is to provide an improved trolley system in which derailment and jamming tends to be selfcorrecting, without personal attendance of the operator.

Still another object is to provide a conveyor trolley system whose ability to perform without jamming is much more predictable, when the present invention is employed, than has been in the case of conveyor systems heretofore employed.

The foregoing and other objectives of the invention are achieved by incorporating into each individual trolley a complementary cam structure at the leading and trailing ends, to insure smooth pushing engagement between successive trolleys, when they are traveling on a track of a specified co-acting type.

The same structure which incorporates the pushing engagement cam structures may also incorporate a derailment inhibiting cam for engaging the track at moments of partial derailment, and tending to force the trolley back onto the track.

The foregoing and other objects and advantages of the invention will best be understood from the following description of one preferred specific embodiment, which should be read with reference to the accompanying drawings.

The drawings illustrate the incorporation of the invention into a conveyor trolley system having many features already in widespread use, and familiar to those having knowledge of the art.

The track is usually steel tubing, typically 1-1/16 inches or l-5/ l 6 inches in outside diameter. This tubing is bent into the desired curves and inclines, along which the individual trolleys are required to travel.

Each trolley is comprised of a load-carrying structure (typically a horizontal bar for hanging garments) which is suspended from the track at its leading and trailing ends by means of a trolley head assembly. The longitudinal dimension of an individual trolley is often sufficiently great in relationship to the curvature of the track to be an important cause of the operating difficulties already mentioned.

It will be understood that successive individual trolleys are not connected to one another; a series of trolleys is merely pushed along the track by end-to-end engagement. However, although there is no positive coupling employed, the present invention uses a nesting cam system at the leading and trailing ends of each trolley, so that many of the advantages of a coupling are accomplished without actually employing a positive connection. It will, therefore, be convenient to describe the nesting leading and trailing cam surfaces as coupling cam surfaces.

Also, it will be understood that the track incorporates many upward and downward inclines; not all the track curvature is in a horizontal plane. Nevertheless, for convenience, the term track curvature will be employed to include all departures of a track from a perfectly straight line.

It will be necessary to make several references to the track as an overhead monorail, or to track rollers as being disposed above" the track in a horizontal plane. References will likewise be made to vertical transverse planes, etc. It will be understood that these refer to the geometric relationships between track and trolley in the normal straight-line horizontal track characteristic of the greatest part of the typical conveyor installation. Actually, at inclined places, these geometric definitions do not apply.

Also, because of the substantial length of a typical individual trolley, as compared with curvature in the track, the longitudinal center line of a trolley will not be disposed in the same vertical plane as the longitudinal center line of the track at places of curve and incline. Nevertheless, for purposes of description, it is convenient to refer to these longitudinal centerlines, and other geometric relationships, with reference to the relationships which exist when the trolley is moving along a straight-line horizontal section of track substantially longer than the longitudinal dimension of the trolley. It will be understood that departures from this geometry will occur at curves and inclines.

In the drawings:

FIG. 1 is a left side elevational view of a leading trolley head constructed according to the present invention;

FIG. 2 is a plan view of the head of FIG. 1;

FIG. 3 is a rear elevational view of the head of FIGS. 1 and 2;

FIG. 4 is a right side elevational view of the head of FIGS. 1 to 3;

FIG. 5 is a right side elevational view of a trailing head form of the invention;

FIG. 6 is a perspective view of a stamped metal body incorporating the coupling cam features of the invention;

FIG. 7 is a right side elevational view of a series of two trolleys, each suspended by a pair of trolley head assemblies illustrated in FIGS. 1 to 5, shown as the second trolley pushes the first up an upwardly inclined section of conveyor track; and

FIG. 8 is a perspective view of a sharp right turn bend in a section of track, showing (fragmentarily) a series of two trolleys as they negotiate the turn with their ends in pushing engagement.

In the drawings, the general conveyor trolley system is suggested only fragmentarily in FIGS. 7 and 8, and indicated by the numeral 10, since the present invention is an improvement on a system well known to those skilled in the particular art, as to features not illustrated in the drawing.

The standard tubular track 11 is shown in a typical upward moving incline in FIG. 7 and in a typical right turn in a horizontal plane in FIG. 8.

The manner of suspending the track 11 from the ceiling or some type of frame structure, without interfering with the free passage of the trolleys is illustrated only fragmentarily because the construction and installation of such suspension is well known to those skilled in the art of this conveyor. It will be seen that the track 11 is supported at spaced intervals by C-supports 12, which are adjustably clamped at 13 to downhanging overhead tubular support 14 (see FIG. 8).

A series of trolleys travel along track 11 in end-toend pushing engagement as illustrated in FIGS. 7 and 8, in which two individual trolleys are identified by the numerals 15 and 16.

The direction of movement of the trolleys l5 and 16 is indicated by the arrow 17, and may be conveniently referred to as movement in a downstream or downtrack direction.

Typically, all the trolleys in a given system are identical. However, some installations may permit or require an assortment of trolleys; the invention will be applicable if its limitations are met. Also, the trolley designs are as diverse as their many applications. In the present embodiment, a typical garment trolley is illustrated.

Trolley 15 is seen to be comprised of a garmentcarrying bar 18, and a pair of trolley head assemblies, a leading trolley head assembly 19, and a trailing trolley head assembly 20. Garment-carrying bar 18 is provided with a number of upward projecting stops 21 to prevent the sliding of garment hangers when trolley 15 is traveling on an inclined part of track 11.

The most readily observable structural features of the invention are in the

trolley head assemblies

19 and 20, which are illustrated in FIGS. 1 to 4, although, as will be explained hereinafter, there is a cooperating relationship between cam surfaces incorporated in the trolley head assembly, and the structure of both track 11 and trolley 15.

Leading trolley head assembly 19 is illustrated in detail in FIGS. 1 to 4. Typically, the trailing trolley head assembly 20, illustrated in FIG. 5, is identical in all respects to leading trolley head assembly 19, except for certain differences related to a species of the invention in which automatic switching is employed, as will be explained hereinafter.

In FIG. 3, the viewer sees leading trolley head assembly 19 as it moves toward the viewer on tubular track 11 (seen in transverse cross-section). Referring to FIG. 3, and to the plan view of FIG. 2, and the left and right side views of FIGS. 1 and 4 respectively, one sees that the parts of assembly 19 are assembled on a vertically extended hanger 30. At its lower end, hanger 30 carries a hanger swivel 31 for providing swiveling attachment to the leading end of carrier bar 18. In the preferred embodiment illustrated, hanger 30 is in the form of a box formed out of sheet steel, with an open face at the right side, outboard of track 11, for accommodating selectively positionable automatic switch actuators 35 seen in FIG. 4.

The swivel 31 is preferably a vertically disposed swivel shaft 36, mounted in a swivel shaft support 37, which projects under track 11 so as to dispose the vertical axis 38 of swivel shaft 36 in a vertical plane lying in the longitudinal axis of (a straight-line portion of track 11. Typically, swivel shaft 36 rotatably swivels in the leading end 18a of carrier bar 18.

The upper end of hanger 30 carries a body shaft 40, which projects horizontally, transversely to track 11, over track 11.

Shaft 40 provides swiveling attachment of a body 41, which may be referred to as roller body 41, since it carries a pair of

rollers

42 and 43 which roll on tubular track 11 as best seen in the head-on view of FIG. 3. Preferably

rollers

42 and 43 are symmetrically recessed to ride on the cylindrical surface of tubular track 11.

Rollers

42 and 43 are rotatable on

shafts

44 and 45, which are mounted in body 41.

It will be seen that the axis of body swivel shaft 40 is horizontal, and transverse to tubular track 11, and spaced above a horizontal plane defined by the axes of

roller shafts

44 and 45.

It will also be seen from FIGS. 1 to 4 that the swiveling action of body 41 around body shaft 40 is limited by a body-swiveling stop 47, which projects inwardly toward tubular track 11, from the left side of hanger 30, and limits the rotation of body 41 about shaft 40.

Body 41 is illustrated in perspective in FIG. 6, and entirely disassembled from leading trolley head assembly 19. Body 41 is shown in the preferred form of the invention as formed entirely as a unit out of stamped sheet metal. This construction is not only betterfor purposes of the invention, but also less expensive, than fabrication by casting as generally employed in the prior art, and heretofore believed to be the preferred method of fabrication. Stamped sheet metal has unique advantages in providing the smooth camming surfaces required by the present invention, as will be seen hereinafter.

FIG. 6 reveals that body 41 has what may be referred to as an inverted channel construction with an inboard skirt 51 (adjacent hanger 30 in the assembly 19) and an outboard skirt 52. Also, body 41 has its sheet mate-. rial downfolded at leading and trailing ends to form a smoothly contoured projecting leading cam 53 and a smoothly contoured recessed trailing cam 54. Preferably, projecting leading cam 53 and recessed trailing cam 54 are symmetrical about a central plane passing through the center line of body 41, and containing the longitudinal axes of both tubular track 11 and carrier bar 18, as well as the vertical axes 38 of hanger swivel shaft 36. Also preverably, the outboard skirt 52 incorporates a skirt cam indicated generally by the number 55, and including a central portion 56 closely approaching track 11, and outwardly diverging leading and trailing

portions

57 and 58, respectively. Preferably, skirt cam 55 is symmetrical about a vertical plane transverse to track 11, and passing through both axes 38 and the axes of body shaft 40.

Trailing trolley head assembly 20, seen in FIG. 5, and also in FIGS. 7 and 8, is substantially the same assembly as used for leading trolley head assembly 19; indeed, an identical assembly may be employed. However, in the preferred form illustrated, trailing cam 20 does not carry any switch actuating means 35, and consequently the trailing assembly 20 employs a much smaller hanger 60.

It is important to understand that there is a co-acting relationship between track 11, the maximum trolley links (i.e., spacing along the track between trolley heads of the same trolley), and the configuration of the cam surfaces employed in body 41. For the successful functioning of the inventive combination, these three are related to produce an optimum combination of design flexibility and operating reliability. All curves in track 11 should fall within a range of permitted curvature (including horizontal curves, inclines, or combinations of both). The maximum permitted length of an individual trolley 15 or 16 should correspond to the permitted track curvature range so as to restrict turning angles between two successive trolleys to a suitable predetermined range. The two foregoing ranges will in turn determine, or be determined by, the cam surfaces employed on body 41. The leading and trailing coupling cam surfaces 53 and 54 must provide the best pushing engagement consistent with turning curves within the permitted track curvature range as illustrated in FIG. 8. Also, the skirt cam 55 must provide a configuration of the diverging

portions

57 and 56 which accommodates the curvature of track 11, without producing jamming interference between skirt 55 and track 11. Leading cam 53 and trailing cam 54 must have suitable camming characteristics in the vertical plane so that override jamming does not occur at an incline, such as pushing up an incline illustrated in FIG. 7, provided the curvature incline of track 11 is kept within the permitted range predetermined by the combination.

The pushing earns 53 and 54, and the skirt cam 55 provide a much improved and more reliable form of trolley for automatic switching. In the automatic switching procedure described in preceding paragraphs, it is important that one and only one trolley be diverted by a single automatic switch operation and that no jamming occur at the junction of the branch track to the main track. The cams of body 41 of the present invention provide smooth and powerful pushing engagements throughout most of the branch turnoff, so taht switching errors are less likely to occur, and also so that slightly imperfect operation of the switches does not produce jamming at the branch track junction.

In many installations, the narrow hanger 60 is sufficient for use in a leading trolley head assembly, as well as the trailing head assembly. In such installations, both leading and trailing trolley head assemblies would look exactly like trailing trolley head assembly 20 in FIG. 5. It is more convenient to have only one type of hanger, hanger 60, throughout the entire system, unless the automatic switch actuation is of sufficient complexity to require the use of the larger trolley head assembly illustrated in FIGS. 1 to 4.

The preferred embodiment of the invention has been described with the trolleys traveling in the direction indicated by the arrow 17 in FIG. 8, that is, with the projections 53 leading and the recessed 54 trailing. However, in some installations, because of the location of C-supports 12, on the opposite side of track 11 from that indicated in FIG. 8, it is necessary to have the trolleys traveling oppositely to the direction indicated by arrow 17, to wit: with recesses 54 leading and projects 53 trailing. Even in this form of operation, the invention is found to accomplish substantial coupling between successive trolleys, and derailment is much inhibited by the camming action between trailing projections 53 and leading recesses 54.

I claim:

1. In a conveyor trolley system in which a series of load-carrying trolleys are movable in rolling suspension from an overhead monorail track, an improved system which includes:

a series of trolleys, each of which has a longitudinal dimensiontalong a longitudinal axis substantially parallel to straight line portions of said track, said longitudinal dimension being limited to a predetermined maximum for any single trolley;

a monorail track including curved portions restricted to a predetermined range of curvature related to said maximum longitudinal dimension for a single trolley to limit the range of turning angle between longitudinal axes of two successive trolleys in pushing engagement with each other; and

each of said trolleys in said series of trolleys including;

a carrier member extending along the longitudinal axis of said trolley;

a pair of trolley head assemblies carrying said carrier member in rolling suspension from said track, said pair comprising a leading head and a trailing head at the leading and trailing ends, respectively, of said carrier, each of said head assemblies including:

a series of two rollers rolling on the upper surface of said track, said rollers having bearing axes transverse to said track, said roller axes defining a horizontal roller axis plane spaced above said track;

a body in which said two roller members are rotatably mounted, said body overhanging said rollers, said body including coupling cam surfaces for making smooth pushing engagement between successive trolleys on said track;

a hanger disposed to one side of said track and extending vertically from said carrier to an elevation above said roller axis plane;

a vertical hanger swivel for connecting the lower end of said hanger to said carrier and permitting said hanger to swivel about a vertical hanger axis;

a horizontal body swivel for connecting the upper end of said hanger to said body at an elevation above said roller axis plane and permitting said body to swivel with respect to said hanger about a horizontal body axis transverse to said track and midway between said roller axes; and

a skirt cam integral with said body and extending downwardly adjacent the side of said track opposite the side at which said hanger is disposed, said skirt cam having a wall surface adjacent said track, which wall surface smoothly diverges downwardly away from the side of said track in both leading and trailing directions to inhibit derailment of said trolley head assembly while permitting accommodation of said assembly to said predetermined track curvature.

2. An improved conveyor trolley system as described in claim 1, in which each of said bodies is a single piece of formed metal sheet comprising an inverted channel section disposed longitudinally with respect to said track, and providing, in its downwardly extending walls, bearing locations for the mounting of said rollers and said body swivel; a downwardly extending side extension formed to provide said skirt cam; and folded sheet material at leading and trailing ends formed to provide said coupling cam surfaces.

3. An improved conveyor trolley system as described in claim 2, in which said formed sheet metal body has sheet material downfolded at the leading end formed into a projecting cam surface having a maximum projection at a vertical plane corresponding to the longitudinal center line of said track; and sheet material at the trailing end of said body is downfolded to form a recessed cam, with maximum recess depth at said vertical plane.

4. An improved conveyor trolley system as described in claim 1, in which, in said trolley head assemblies, said hanger carries a stop means located on said hanger adjacent said body, for limiting the rotation of said body about said horizontal body axis to a predetermined body swiveling angle related to the predetermined range of vertical curvature which can be negotiated by said leading and trailing coupling cam surfaces.

5. An improved conveyor trolley system as described in claim 1, in which said skirt cam is formed with a central portion having minimum clearance of said track, in straight line parts of said track, said central portion being disposed in a vertical plane through said hanger swivel axis, and said skirt cam diverging outwardly from said track, and straight line portions of said track, in both leading and trailing directions, to permit a predetermined range of track curvature without engagement between said skirt cam and said track, except when said skirt cam is operating to inhibit derailment of the trolley head assembly from said track.

6. An improved conveyor trolley system as described in claim 1, in which said coupling cam surfaces are comprised in a projection at the leading end of each of said bodies, having a line of maximum projection in a vertical plane corresponding to the center line of said track; a recessed surface in the trailing end of said body, having a line of maximum recess in said vertical plane; and said vertical axis of said hanger swivel is disposed in said vertical plane.

Claims

1. In a conveyor trolley system in which a series of loadcarrying trolleys are movable in rolling suspension frOm an overhead monorail track, an improved system which includes: a series of trolleys, each of which has a longitudinal dimension along a longitudinal axis substantially parallel to straight line portions of said track, said longitudinal dimension being limited to a predetermined maximum for any single trolley; a monorail track including curved portions restricted to a predetermined range of curvature related to said maximum longitudinal dimension for a single trolley to limit the range of turning angle between longitudinal axes of two successive trolleys in pushing engagement with each other; and each of said trolleys in said series of trolleys including; a carrier member extending along the longitudinal axis of said trolley; a pair of trolley head assemblies carrying said carrier member in rolling suspension from said track, said pair comprising a leading head and a trailing head at the leading and trailing ends, respectively, of said carrier, each of said head assemblies including: a series of two rollers rolling on the upper surface of said track, said rollers having bearing axes transverse to said track, said roller axes defining a horizontal roller axis plane spaced above said track; a body in which said two roller members are rotatably mounted, said body overhanging said rollers, said body including coupling cam surfaces for making smooth pushing engagement between successive trolleys on said track; a hanger disposed to one side of said track and extending vertically from said carrier to an elevation above said roller axis plane; a vertical hanger swivel for connecting the lower end of said hanger to said carrier and permitting said hanger to swivel about a vertical hanger axis; a horizontal body swivel for connecting the upper end of said hanger to said body at an elevation above said roller axis plane and permitting said body to swivel with respect to said hanger about a horizontal body axis transverse to said track and midway between said roller axes; and a skirt cam integral with said body and extending downwardly adjacent the side of said track opposite the side at which said hanger is disposed, said skirt cam having a wall surface adjacent said track, which wall surface smoothly diverges downwardly away from the side of said track in both leading and trailing directions to inhibit derailment of said trolley head assembly while permitting accommodation of said assembly to said predetermined track curvature.