US3598448A

US3598448A - Method and apparatus for manufacture of side brooms

Info

Publication number: US3598448A
Application number: US839287A
Authority: US
Inventors: Donald G Kirk
Original assignee: Elgin Sweeper Co
Current assignee: Elgin Sweeper Co
Priority date: 1969-07-07
Filing date: 1969-07-07
Publication date: 1971-08-10
Anticipated expiration: 1988-08-10

Abstract

Groups of wires used in side brooms for streetsweepers and similar apparatus are manufactured by apparatus comprising a wire sorter that vibrates to position a specified number of wire broom strands in vertical and lateral position for bending and forming. A transversely moving hydraulic cylinder actuated ram means bends the group of wire through a forming die generally at their midpoint into a hairpinlike configuration. The method of forming the bristle groups and filling wire broom segments includes the steps of counting a predetermined number of straight wire broom strands, orienting these strands in a predetermined relation to one another, holding the predetermined number of oriented strands at an upper and lower position adjacent a forming means, forcing the wire strands through a forming die by means of a ram that moves transverse to the central axis of the group of strands and removing the bent group of wire strands from the forming die and inserting them into a wire broom segment.

Description

United States Patent OF SIDE BROOMS 14 Claims, 8 Drawing Figs.

US. Cl v.

Int. Cl

Field of Search References Cited UNITED STATES PATENTS 3/1890 Young 1/1914 Wiens 1,525,246 2/1925 LeBoeuf ABSTRACT: Groups of wires used in side brooms for streetsweepers and similar apparatus are manufactured by apparatus comprising a wire sorter that vibrates to position a specified number of wire broom strands in vertical and lateral position for bending and forming. A transversely moving hydraulic cylinder actuated ram means bends the group of wire through a forming die generally at their midpoint into a hairpinlike configuration. The method of forming the bristle groups and filling wire broom segments includes the steps of counting a predetermined number of straight wire broom strands, orienting these strands in a predetermined relation to one another, holding the predetermined number of oriented strands at an upper and lower position adjacent a forming means, forcing the wire strands through a forming die by means of a ram that moves transverse to the central axis of the group of strands and removing the bent group of wire strands from the forming die and inserting them into a wire broom segment.

METHOD AND APPARATUS FOR MANUFACTURE OF SIDE BROOMS BACKGROUND OF THE INVENTION 1. Field of the Invention This invention generally relates to the apparatus and method of making brooms and is particularly concerned with the apparatus for forming the groups of wire broom bristles by counting and orienting a predetermined number of wire broom bristle elements and bending them so that they may be readily incorporated in the broom structure. It further includes the method of automatically forming the bristle groups and inserting them in the broom segment.

2. Prior Art Heretofore the methods of and apparatus for manufacturing wire broom bristles and making wire brooms have included a great number of individual operations, each performed mainly by hand or with the aid of simple and crude equipment separated by both time and space. Thus, for example, counting and sorting of the predetermined lengths of wire which are used as broom bristles has been carried out in one place by one person with a relatively crude piece of equipment and the counted and sorted wires have then been taken to another place where another or the same workman with different equipment has bent the wires and forwarded them to yet another location for insertion of the bundles of bent wires into the broom segments.

Many disadvantages are associated with these prior art structures and methods including the fact that the wires became jumbled or mixed during the transfer from the counter or sorter to the bender so that the resulting broom many times had an uneven bristle structure that produced inconsistent results and uneven wear of the bristles. Thus, for example. when a wire having a generally rectangular cross section is used, it may be appreciated that if the wires become disarranged so that they are bet transverse to the greater diameter of the wire cross section-there may be a tendency for the wires to be strained beyond their elastic limit and thereby weakened to create the possibility of the bristles breaking at this point and being thrown from the rapidly rotating broom. This situation is not only dangerous, but the loss of bristles reduces the sweeping efficiency and increases maintenance.

In addition to the technical disadvantage of poor quality the prior art structures and methods have the inherent disadvantages of slow production and large space requirements. Moreover, the greater amount of human handling of the wires during the transferring of the wire bristles through each of the many individual stages of production requires much extra time and entails additional storage space for the wires during the various stages of production.

SUMMARY OF THE INVENTION The disadvantages associated with the prior art are overcome by the method and apparatus of the present invention. Economies of money, time and space are effected while producing a consistently higher quality product than has heretofore been known to the prior art.

The apparatus of the present invention generally comprises a wire sorter means which utilizes vibration and gravity to effectively sort and position a predetermined number of straight lengths of wire that are quickly and uniformly bent by a wireforming means.

The wire sorter means comprises a generally vertically disposed tubular structure having a flared upper end for receiving a large quantity of predetermined lengths of broom bristle wires. A sorting grid is affixed across the lower end of the tubular hopper structure so that only a predetermined number of wire lengths may pass therethrough in only a predetermined orientation. The wire lengths are caused to pass through the grid by the vibratory motion imparted to the hopper. This vibratory motion causes the wire elements to be jostled until such time as they pass through an opening in the grid. Where wire elements having rectangular transverse cross sections are used the holes in the grid will be of a rectangular cross section and thus the wire elements passing through the grid will be oriented with respect to one another.

The number of openings in the grid and their particular orientation may of course, be arranged to provide maximum effectiveness in the broom design. The count of the wire e iciments of course is implicit in the number of holes in thegrid which, because of the grid construction will always be filled under normal operating conditions. Two vertically spaced rows of rodlike members wherein each of the layers is oriented at to the other has been found to provide a very effective grid structure. The rounded edges of the members greatly facilitate movement of the wire elements under the vibrating conditions and provide long wear and low maintenance. Masks and wire guide members may be provided on the grid member to vary the capacity of the grid and to increase its'efficiency respectively.

As the wires pass through the grid they fall through a chute and come to rest with their lower ends in a lower holder cup. In this position the wires will be vertically disposed adjacent or in front of a die-forming means with their lower ends held in a wire holder cup and their upper ends in the openings in the sorting grid. A forming ram energized by a hydraulic or pneumatic ram means is moved transversely across the group of wires at their midsection to force them through a wire-forming die that doubles them up into a generally hairpinlike configuration. The ram is constructed with a pair of sidewalls which moves past the vertically positioned wires before the crossbarforming piece actually begins the forming operation. By this means the wires will be retained in their relative positions and orientations in the group as they are being bent. As the wires pass through the forming die they may be taken by a workman and inserted into a broom segment.

According to the present invention the method of producing bent wire broom bristles and manufacturing wire brooms comprises feeding predetermined lengths of broom bristle wire into a sorting apparatus, vibrating the sorting apparatus to pass a predetermined member of bristle wires in a predetermined orientation into a wire-forming means, forcing the wires in the vicinity of their midpoint through a wire-forming die so that the group of bristle wires assumes a generally hairpin configuration, removing the formed wires from the forming die and inserting these wires in a wire broom segment.

BRIEF DESCRIPTION OF THE DRAWINGS Other objects, features and advantages of the invention will be readily apparent from the following description of certain preferred embodiments thereof, taken in conjunction with the accompanying drawings, although variations and modifications may be effected without departing from the spirit and scope of the novel concepts of the disclosure, and in which:

FIG. I is a perspective view of one embodiment of the invention with parts thereof in section and other parts thereof schematically illustrated;

FIG. 2 is an elevational view of the central portion of the apparatus with parts in section;

FIG. 3 is a view of a sorter-counter block taken along the line llIl II in FIG. 4 with the general profile of the hopper superimposed thereon;

FIG. 4 is a cross-sectional view of FIG. 3 taken along the line IV-IV;

FIG. 5 is schematic representation of the group of bristle wires as they are held just prior to their being bent by the ram means;

FIG. 6 is a schematic representation of the group of bristle wires during a sequential stage in the bending and forming operation;

FIG. 7 is a schematic perspective view of the end of the forming ram; and,

FIG. 8 is a view of a broom segment showing groups of bristle wires in place and'a group being inserted.

DESCRIPTION OF THE PREFERRED EMBODIMENT A wire-bending apparatus generally indicated at in FIG. 1 makes possible the sorting and precise bending of a plurality of wire lengths 12. A generally tubular hopper 14 that may be generally vertically disposed may have a flared upper end 15 to facilitate the receipt of a large number of predetermined lengths of wire 12. Across a lower end 14a of the hopper 14 there is affixed a sorter means 16 which allows only a predetermined number of wires to drop through. The lengths of wire 12 may be inserted into the upper end of the hopper in random number and array and be processed by the apparatus into definite groups of definite arrangement. The sorter means 16, as will be discussed in greater detail with respect to FIGS. 3 and 4, includes a grid having a predetermined number of openings therethrough in a predetermined orientation through which the wires may pass. The hopper 14 is secured in a frame 18 by motion-transmitting means 19 and 20 at its upper and lower endsrespectively. These means 19 and 20 allow vibration of the hopper 14 and the attached sorter means 16.

Vibration of the wires in a general up-and-down motion is provided by a vibrating means which may include a connecting rod 23 as may be seen in FIG. 1 in part in dotted lines attached at one end to the hopper 14 and having its other end eccentrically attached to an axle 210 on which is mounted a wheel 21 so that as the wheel 21 turns, the hopper 14 will be vibrated in a general up-and-down motion so that the straight lengths of wire 12 will jostle about in the hopper until they orient themselves into alignment with an opening and then pass through this opening by the force of their own weight. The pulley wheel 21 is driven by a belt 24 that passes over a motor pulley 25a driven on a motor 25. The motor 25 may be conveniently mounted on the frame 18. The pulley 21 is suitably mounted in a bushing 22 that may also be attached to the frame 18. The common frame 18 and its components allow great flexibility in positioning of the various elements of the apparatus. Thus, the frame member 18, 180 may comprise U-shaped channels each having upstanding legs 18d, [8e and a bottom crosspiece 18f. This attachment of the various elements of the apparatus to a common rigid frame 18 has the advantage of providing a sturdy maintenance-free, vibrationless construction.

Referring to FIG. 4 the features of the sorter means 16 may be seen in greater detail. In the illustrated embodiment, which we have found to provide excellent results, the sorter means 16 comprises an upper portion 30, a central grid portion 32 and a lower portion 34. A guide member 36 having an internal guide surface 40 may be positioned in a recess 38 in the upper member to provide a-connection means with the hopper 14. The internal surface 40 guides the wire members through an opening 42 onto a mask 44 and through an opening 46 in the mask. It is pointed out that with the hopper substantially filled with the elongated wire bristle members 12 the inclined guide surface 40 would tend to exert lateral pressure urging them into frictional side-by-side engagement at their lower end. However, with the elongated wire elements being vigorously jostled in a generally up-and-down motion this frictional engagement is substantially reduced whereby the wires 12 may pass more freely through the grid. The mask 44 will determine the area of the grid and the number of openings therein that are exposed to the wires. In this manner an easy variation in the configuration and area of the grid is possible.

In the central grid portion 32 a plurality of generally horizontally disposed rodlike members 48 pass through an opening 52 in a first direction and are anchored at their ends 50 to the central portion 32. The rodlike grid members 48 may be parallel to each other and generally lie in the same plane. The spacing of the rods will depend upon the dimensions of the wire elements that will be allowed to pass through the sorting means 16. In an embodiment of the invention the wire members 12 are of a rectangular transverse cross-sectional configuration so that in this instance the rodlike members 48 would be spaced apart a distance slightly greater than one of the wire bristle dimensions.

A second set or layer of rods 54 extend across an opening 58 in the central portion 32 in a second direction and may be spaced apart a distance equal to the other dimension of the wire members in our embodiment. The members 54 also may be generally parallel to each other and may lie in approximately the same plane although it is to be understood that to form the grid openings 49 the rods 54 will be oriented with their axes at an angle of about 90 to the axes of the grid members 48. As seen in the plan view of FIG. 3 the spaces 49 between the rods 48 and 54 respectively will generally be equal to the cross-sectional configuration of one piece of wire. The grid is thus formed of two layers of transversely extending members 48,54.

With the above construction of the grid across the bottom of the hopper 14 the wires 12, being jostled vertically up and down atop the sorting grid, will fall quickly into the spaces 49. Each of the members 54 has an end portion 56 that is mounted in the central portion 32. If desired, the individual members 48 and 54 may be rotatably mounted so that wear will be distributed about the periphery of the rods. An opening 58 smaller in size than the opening 42 bounds the opening 52 in which the members 54 are disposed. To further guide the wire members 12 as they pass through the opening and sorting grid there has been provided a guide surface 60 in the lower portion 34. This guide surface 60 will further assure the correct orientation of the wire members.

It may be seen in FIG. 4 that the rounded configuration of the rod 48 will facilitate and guide the wire members such as illustrated by the wire element 12a through the grids. The wire element 12b illustrates the wire member as it is passing through the opening 49 and the wire element 12c illustrates a typical wire element with its lower end resting in the cup holder.

Having passed through the sorting means 16, the wire members 12 drop by the force of gravity through a chute 70 and have their lower ends supported in a cuplike member 64. The chute 70 may be of a downwardly tapering configuration having an enlarged end 71 below the sorting grid means of a dimension to receive any wires passing therethrough. It is pointed out that although the lower ends of the wire have passed through the openings 49 and the grid means 16 their upper ends are still being jostled and therefore the chute means will serve to guide the wire elements until they have passed beyond the effect of the vibrating hopper and grid. At its lower end the chute 70 has a smaller opening 72 which is just above and adjacent to the wire die forming means 75.

As seen in FIG. 2 the wire-forming die generally indicated at 75 may include a pair of forward walls 76 converging toward a final forming element 77 which has an inner flared end 78 and an outer opening 79. Spaced along and from the converging walls 76 are a plurality of forming elements 80 which allow the wire to pass freely thereagainst as they are being bent. These elements 80 may be rollers turning on axes 81 that extend between forming die sideplates 82. The sideplates 82 may be parallel or may be tapered toward the opening 79. The converging walls 76 space these sideplates.

Prior to being bent the wires will be vertically disposed with their lower ends received in the cup 64 and their upper ends held by the sorting grid means as illustrated by the element 120 in FIG. 4 so that their orientation prior to bending will be fixed within the limits of the flexibility of the wire elements. With the group of wire elements so held at either end in position across the opening 84 of the wire-forming die, a ram shown in solid lines at will begin moving in a direction transverse and generally perpendicular to the axes of the wires to intersect the wires at their midpoints and begin to force them into and through the wire-forming die 75. The ram 90 as shown in perspective view in FIG. 7 includes a pair of sidewalls .91, 92 having rounded forward end edges 91a,.92a respectively. The

sidewalls

91, 92 are held in spaced relationship by a solid platelike crossmember 94 that flares outwardly near the rear end 90b of the ram. The rear end of the ram 90b is connected by suitable means 96 to a ram power means 98 that is mounted in a frame member 180 which in turn is connected to the frame 18 so that the force of the ram power means may be transmitted to the ram 90 to force it through the forming die.

A pair of joining members 18b on the rearward side of the frame 18 are attached to the frame member 18 by suitable fastening means 100 in holes 102 that are provided in the frame flange portion 18d. The joining membersare also permanently affixed to the frame portion 18a. Another similar pair of joining members 18c on the forward side of the frame 18 likewise are attached by suitable fastening means 100 in holes 102 on the frame flange portions l8e and permanently secured to frame portion 18a to thereby rigidly connect the frame portion 180 to the frame 18. Both the chute means 70 and the cup 64 have supports 70a and 64a respectively, which allow adjustable attachment to the frame 18. The frame member 180 extends through the frame 18 and supports the wire die forming member on this extension.

As shown in the dotted lines indicated at 90a the ram 90 will pass through the forming die and opening 79 to thereby form the wires into a hairpinlike configuration illustrated at 12d.

From the foregoing description the many advantages of the instant invention over the prior art should now be apparent. Thus, in a single compact apparatus a predetermined number of wires of predetermined length are oriented, positioned and bent into specifically oriented groups or bundles that may be readily inserted by a workman into a broom segment. When the hopper is full the vibration thereof causes the predetermined number of openings in the grid to be filled hence the apparatus does perform what may be considered a wire-count ing function as will be understood by those skilled in the art. Attachment of the various elements of the apparatus to a common frame and a relatively few, simple moving parts results in an efficient easily maintained machine.

The method of producing bundles or groups of wire broom bristles according to the present invention includes the steps of cutting lengths of suitable broom wire to a substantially uniform predetermined length as is represented by the elements l2, counting a predetermined number of these wire lengths l2, arranging these wires in a predetermined orientation with respect to each other, holding the thus arranged group of wires in place with respect to each other, and, bending the thus arranged group of wires generally about their midpoint so that the group of bristle wires assumes a generally hairpin configuration. The method of producing the wire brooms comprises the further steps of taking and retaining the thus formed group of wires in their predetermined orientation, inserting this group of wires in a wire broom segment and securing each of said wire groups in position to form a side broom.

In terms of the apparatus previously described the method of producing bent wire broom bristles comprises feeding quantities of uniform length straight broom bristle wire 12 into a generally vertically positioned hopper 14 so that the hopper is substantially full, vibrating the hopper 14 by means of a vibrating means 23, 25 whereby the wires 12 are jostled in the hopper 14 above a grid means 48, 54 until such straight wire lengths 12a pass through the openings 49 as exemplified by the wire length 12b and pass downwardly under the force of gravity into a lower cup 64 which holds their lower end so that at this point the wire lengths 12c are held adjacent a wireforming means 75 with their lower ends in the cup 64 and their upper ends in the grid 48, 54, and bending the wire lengths thusly positioned by means of a ram 90 bearing against their midpoint and forcing the group of bristle wires through the forming die 75 so that the group of bristle wire assumes a generally hairpin configuration. Again in terms of the apparatus the method of manufacturing the wire brooms com prises the additional steps of removing the thus formed and oriented group of wires 12d from the forming die 75, inserting this group of formed wires [2d in a wire broom segment as is shown in FIG. 8 and securing the groups of wires in position in the broom segment 110. lt is an important aspect of the invention that the wires are retained in their precise orientation and are secured in that orientation in the wire broom segment 1 10.

Although minor modifications might be suggested by those versed in the art, it should be understood that I wish to embody within the scope of the patent warranted hereon all such modifications as reasonably and properly come within the scope of my contribution to the art.

I claim as my invention:

1. A wire-forming apparatus comprising a sorter means for vertically orienting a predetermined number of wires in predetermined spaced relation to one another in a vertically disposed group, a generally vertically disposed hopper means for accommodating predetermined lengths of wire in vertical position, said lengths of wire having upper and lower ends, a wire positioner means for holding said group of wires in a predetermined generally vertical position, and a wire-forming means generally horizontally positioned for bending said vertically oriented and positioned group of wires.

2. A wire-forming apparatus according to claim 1 wherein said sorter means includes a grid means having a predetermined number of openings of predetermined size and configuration therein whereby the wires in said hopper means are oriented by said grid.

3. A wire-forming apparatus according to claim 2 wherein said wire positioner means includes said grid means and a lower stop means, said grid means being adapted to hold the upper ends of the wires passing therethrough and said lower stop means being adapted to hold the lower end of said wires.

4. A wire-forming apparatus according to claim 3 wherein said apparatus includes a vibrator means connected to said hopper means for vibrating said hopper to cause the wires in said hopper to pass through said grid means.

5. A wire-forming apparatus according to claim 3 wherein said wire positioner means further includes a guide chute positioned below said grid means and above said wire-forming means and wherein said lower stop means includes a cuplike member positioned below said wire-forming means, said guide chute, forming means and lower stop means being adjustably attached to a frame means whereby they are adjustable relative to each other and to said counter and sorter means.

6. A wire-forming apparatus according to claim 1 wherein said wire-forming means includes a power ram and a wireforming die, said ram being adapted to .move generally horizontally transversely against said group of vertically positioned wire lengths and to force said group of wires through said forming die.

7. A wire-forming apparatus according to claim 6 wherein said ram means is of a generally H-shaped transverse crosssectional configuration, the vertical side portions extending beyond the crossbars portions, said extending side portions being spaced and of a length to pass about and beyond said group of wires so that said crossbar bears against said group and forces it through the die.

8. A wire-bending apparatus including a generally vertically disposed hopper means for receiving a quantity of vertically disposed wires of predetermined length, a grid means connected with said hopper allowing a predetermined number of wires to pass therethrough and orienting said wire lengths in a vertically disposed group below said hopper means, and a wire-forming means below said grid means for bending said group of wires.

9. A wire-forming apparatus according to claim 8 wherein said wire-forming means includes a ram means, a forming die and a wire-positioning means for holding said group of wires between a ram means and a forming die, said forming die comprising a pair of walls converging toward a final forming member, said final forming member being generally tubular and having an inner flared end and an outer opening, said ram means forcing said wires through said outer opening to form them.

10. A wire-forming apparatus to claim 9 wherein a plurality of roller-type forming elements are spaced along and from the converging walls.

11. A wire-forming apparatus including a frame, a means allowing only a predetermined number of wires to pass therethrough, a wire positioner means having an upper and a lower end, said positioner lower means being adjustably mounted on said frame below said means allowing only a predetermined number of wires to pass therethrough whereby the positioner may be adjusted to accommodate wires of different length, means adjustably mounted on said frame at a point intermediate said upper and lower ends of said wire positioner for bending said wires.

12. A method of forming prearranged groups of wire broom bristles including the steps of allowing all but one end of a predetermined number of wire lengths to pass into a grid having a predetermined number of openings, said wire lengths having an upper end and a lower end, retaining said lower ends at a level so that the upper end remains in the grid, the thus arranged group of wires being positioned adjacent a wire forming means and forming the wires into a predetermined configuration.

13. A method of forming prearranged groups of wire broom bristles according to claim 12 wherein each of the wire lengths has a generally predetermined cross-sectional configuration corresponding to the configuration in said grid, and including the step of arranging the wire lengths into a predetermined spaced orientation with respect to each other.

14. A method of forming wire broom bristles according to claim 13 wherein the wires are formed into a predetennined configuration by a transversely moving ram .means contacting said group generally at their midpoint and driving said group through a wire die while retaining said wires in their relative orientation to each other, and including the further steps of removing the formed wire groups from the die while retaining their relative wire orientation and inserting said groups of wire in a broom segment to form a side broom.

Claims

6. A wire-forming apparatus according to claim 1 wherein said wire-forming means includes a power ram and a wire-forming die, said ram being adapted to move generally horizontally transversely against said group of vertically positioned wire lengths and to force said group of wires through said forming die.

7. A wire-forming apparatus according to claim 6 wherein said ram means is of a generally H-shaped transverse cross-sectional configuration, the vertical side portions extending beyond the crossbar portion, said extending side portions being spaced and of a length to pass about and beyond said group of wires so that said crossbar bears against said group and forces it through the die.

14. A method of forming wire broom bristles according to claim 13 wherein the wires are formed into a predetermined configuration by a transversely moving ram means contacting said group generally at their midpoint and driving said group through a wire die while retaining said wires in Their relative orientation to each other, and including the further steps of removing the formed wire groups from the die while retaining their relative wire orientation and inserting said groups of wire in a broom segment to form a side broom.