An apparatus for positioning a workpiece in a desired orientation for welding or the like during a manufacturing process is provided. The positioner has a generally vertical support column and a generally horizontal boom which is pivotally coupled to a top end of the support column. At a second end of the boom, the positioner has an arm member with a rotatable shaft extending therefrom upon which a workpiece may be mounted. The column is preferably mounted on a turntable such that the positioner may be rotated about a longitudinal axis of the column. In use, the positioner can move a workpiece up, down, left, right and to and fro to change the location of the workpiece. The orientation of the workpiece may also be changed by rotating the workpiece about a longitudinal axis of the shaft.

CROSS-REFERENCE TO RELATED APPLICATIONS
 Not Applicable.
 STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
 Not Applicable.
 BACKGROUND OF THE INVENTION
 The present invention relates to an apparatus for manipulating the position
 and orientation of a workpiece for welding. More particularly, this
 invention relates to a welder positioner which allows a user to raise,
 lower, move side to side and rotate a large piece of metal to a desired
 location and orientation to assist in the construction and manufacturing
 of any number of large metal devices, mechanisms or apparatus.
 In the manufacturing process, workers are often times required to move
 large metal pieces which are to be welded together to fabricate the item
 being manufactured. As a result, numerous devices have been developed for
 manipulating the location and orientation of these workpieces to assist in
 the manufacturing process. One such device, and the simplest, is merely a
 table or platform which can be raised and lowered, thus raising and
 lowering the workpiece resting on the table. Many of these devices
 incorporate hydraulic cylinders because of their ability to easily move
 heavy objects.
 Numerous modifications have been made to the simple raising and lowering
 table design to provide the user with more freedom in changing the
 orientation of the workpiece. Some of the changes include making the
 tabletop surface rotatable, thus permitting the user to not only raise and
 lower the workpiece but to rotate the workpiece in a horizontal manner.
 Another modification to the raising and lowering platform design is to
 provide a way for the tabletop to move from a generally horizontal
 orientation to a vertical orientation, thus providing the user with even
 more freedom to change the orientation of the workpiece. While these
 devices certainly present an advance in the art over simply laying items
 to be joined side by side on the ground, these devices provide only a
 limited number of movements and hence a limited number of positions in
 which to orient the workpiece or workpieces.
 Therefore, there is a need for a workpiece positioner which can easily and
 efficiently move large workpieces through a virtually infinite number of
 locations and orientations, including up, down, left, right, to and fro
 and clockwise and counterclockwise rotation in any location. The present
 invention overcomes the drawbacks of the prior art and fills these and
 other needs.
 BRIEF SUMMARY OF THE INVENTION
 In order to overcome the above-stated problems and limitations, and to
 achieve the noted objects, there is provided a welder positioner having a
 generally vertical and upright support column with a top end, a generally
 horizontal boom that is pivotally coupled with the top end of the support
 column, an arm member pivotally coupled to and rotatable about a second
 end of the boom, and a shaft extending outwardly from the arm member and
 rotatable 360.degree. about its longitudinal axis upon which a workpiece
 may be coupled.
 In general, a user of the positioner can move a workpiece through a large
 generally vertical arc by way of a boom cylinder which is coupled with the
 column in the boom. By extending the length of the boom cylinder, the boom
 pivots about its connection to the column and the second end of the boom
 travels through a large and generally vertical arc. Additionally, the user
 can independently move the workpiece through a smaller generally vertical
 arc by way of an arm member cylinder which couples the boom with the arm
 member. By extending the length of the arm member cylinder, the arm member
 pivots about its connection to the second end of the boom and travels
 through a smaller generally vertical arc.
 Further, a user of the positioner may also move the workpiece through a
 large and generally horizontal arc by way of the column resting on a large
 turntable. As a result, the user may rotate the positioner about the
 longitudinal axis of the generally vertical column. Further still, the
 user has even more freedom of moving the workpiece by providing a motor
 coupled with the shaft extending from the arm member. By activating the
 motor, the user may rotate the workpiece about the longitudinal axis of
 the shaft to position the workpiece in the desired orientation.
 Further objects, features, and advantages of the present invention over the
 prior art will become apparent from the detailed description of the
 drawings which follows, when considered with the attached figures.

DETAILED DESCRIPTION OF THE INVENTION
 Referring initially to FIG. 1, numeral 10 generally designates a first
 embodiment of an apparatus for positioning workpieces in a desired
 orientation for welding. The apparatus 10 may also be called a welder
 positioner 10 and it generally includes a column 12, a boom 14, an arm
 member 16 and a shaft 18. The positioner preferably also includes a boom
 cylinder 20, an arm member cylinder 22, a turntable 24 and a hydraulic
 power unit 26.
 The column 12, as viewed in greater detail in FIG. 10, is preferably an
 elongate member in a generally vertical orientation and has a top end 28
 and a bottom end 30. In the present embodiment, the column 12 includes a
 post 32 that is essentially a square tube having a front wall 34, a back
 wall 36 and first and second side walls 38,40. The post 32 is preferably
 made of steel and the walls 34,36,38,40 of the post are of sufficient
 thickness to support the loads desired to be positioned. The post 32
 includes a cylinder coupler bracket 42 located on the front wall 34 of the
 post. The cylinder coupler bracket is for coupling the boom cylinder 20
 with the column 12 and is preferably a pair of flanges 44 extending
 outwardly from the post 32. Each of the flanges 44 has a bore 46
 therethrough for receiving a pin 48.
 As can be seen in FIGS. 1 and 10, the post also includes a shelf 50
 extending outwardly from the first sidewall 38 of the post 32. The shelf
 50 supports the hydraulic unit 26 which includes an electric motor 52 and
 a fluid reservoir 54. The electric motor 52 is directly coupled to a
 hydraulic pump (not pictured) that is contained in the fluid reservoir 54.
 It should be noted that if a user desired to have a hydraulic power unit
 external from or separate from the positioner 10, one would not need the
 bracket. However, in an effort to make the positioner a self-contained
 unit, the shelf 50 for supporting the hydraulic power unit has been found
 desirable. Additionally one could remove the shelf by locating the fluid
 reservoir and hydraulic pump inside the post 32.
 Also preferably mounted on the column 12 are a hydraulic manifold 56 and an
 electrical power supply box 58. The manifold 56 controls the flow of the
 hydraulic fluid to the various hydraulic components of the positioner.
 Preferably, the cylinders 20,22 include counterbalance valves or safety
 check valves wherein the orientation of the workpiece would not change if
 a hydraulic hose 60 were to leak or rupture. While the manifold has
 corresponding control levers 62 that have been mounted on the post 32, the
 control levers 62 could be positioned in a movable control unit located
 remotely from the column 12, wherein an operator of the positioner could
 stand, for example, out near the workpiece and still control the operation
 of the positioner. However, for safety reasons, it has been found
 beneficial to locate the control levers 62 on the column 12, whereby the
 operator cannot stand in an area where the workpiece is moving. The
 electrical power supply box 58 is coupled to an external electrical power
 source and simply supplies electrical power to the electric motor 52 of
 the hydraulic power unit 26.
 The post 32, at the bottom end 30 of the column 12, includes support
 brackets 64. The support brackets, as illustrated, are welded to the first
 and second sidewalls 38, 40 of the post and to the turntable 24 to help
 maintain the post 32 in a generally vertical and upright position during
 the operation of the positioner.
 The column 12 also includes a pair of upwardly extending plates 66 at its
 top end 28. The plates are preferably welded to the post 32 and extend
 upwardly therefrom. Each of the plates 66 contain a bore 68 therethrough
 for facilitating the pivotal coupling of the boom 14 to the top end 28 of
 the column 12. While the present embodiment features plates 66 coupled to
 the sidewalls of the post 32, it is within the scope of the present
 invention to merely have the sidewalls 38, 40 of the post 32 extend
 upwardly beyond the front and back walls 34, 36 of the post 32.
 The boom 14, as seen in FIGS. 1 and 11, has a first end 70 and a second end
 72. The first end of the boom is pivotally coupled with the top end 28 of
 the column via a pair of pins 74 which pass through bores 76 in the first
 end 70 of the boom 14 and the bores 68 in the plates 66 of the column 12.
 The boom is preferably an elongate member with a U-shaped cross-section.
 The boom has a bottom wall 78 and first and second sidewalls 80, 82. The
 three walls 78, 80, 82 of the boom 14 define an open area 84 between the
 sidewalls 80, 82 and above the bottom wall 78. By omitting a top wall from
 the boom, and having the boom have a U-shaped cross-section, the arm
 member cylinder 22 may go down between the sidewalls 80,82 and into the
 open area 84 during use of the positioner 10 when the arm member 22 is
 rotated such that the shaft 18 points in a generally downward direction.
 To strengthen the boom 14 and to accommodate for the omission of a top
 wall, the boom is provided with sister plates 86 and supports 88.
 At the second end 72 of the boom 14, the boom includes first and second
 extension arms 90, 92. The extension arms are for supporting the arm
 member 16 and have bores 93 therethrough to facilitate the pivotal
 coupling of the arm member to the boom. While the extension arms 90, 92
 are separate pieces which have been welded to the sidewalls 80, 82 of the
 boom in the present embodiment, as with the plates 66 on column 12, it is
 within the scope of the present invention to provide the extension arms
 90, 92 by simply having the sidewalls 80, 82 of the boom 14 extend beyond
 the bottom wall 78 of the boom.
 The boom also includes a first cylinder coupler bracket 94 and a second
 cylinder coupler bracket 96. The first cylinder coupler bracket 94 is
 located on an underneath side 98 of the bottom sidewall 78 of the boom 14
 and is for coupling the boom 14 within the boom cylinder 20. As with the
 cylinder coupler bracket 42 on the column 12, the first cylinder coupler
 bracket 94 is preferably a pair of outwardly extending flanges 100. The
 flanges 100 both include a hole 102 therein for receiving a pin 104 to
 facilitate the pivotal coupling of the boom cylinder 20 with the boom 14.
 The second cylinder coupler bracket 96 is preferably located at the first
 end 70 of the boom 15 intermediate the sidewalls 80, 82 of the boom and
 above the bottom wall 78 of the boom. The second cylinder coupler bracket
 96 similarly includes a pair of flanges 106 that extend outwardly from the
 boom and have bores 108 therethrough for receiving a pin 110 to facilitate
 the pivotal coupling of the arm member cylinder 22 with the boom.
 The arm member 16, as seen in FIGS. 1 and 12, has a body 112 and a
 plurality of arms 444 extending outwardly there from. The body 112
 generally functions as a bearing support 114 and preferably takes on a
 box-like shape. The body has a front plate 116, a rear plate 118, a top
 plate 120, a bottom plate 122 and first and second side plates 124, 126.
 The front and rear plates 116, 118 have bores 128 therethrough which are
 coaxial and which jointly receive a bearing 130. In the present
 embodiment, and as best seen in FIG. 6, the bearing 130 is a bushing 132.
 The bushing 132 is generally tubular in nature and extends between and is
 received in the front and rear plates 116, 118 of the body 112. It has
 been found beneficial to have the bushing made of brass. However, the
 bushing could be made of any material capable of withstanding the forces
 placed on it when a workpiece is positioned on the shaft 18. Additionally,
 it is within the scope of the present invention for the bearing 130 to be
 a first ball bearing assembly received in the front plate 116 and a second
 ball bearing assembly received in the rear plate 118.
 Preferably, the plurality of arms 114 include first and second side arms
 134, 136 and a transfer arm 138. The first and second side arms are
 generally parallel elongate members and, as with several other components
 of the positioner, may be cut from a large metal plate or sheet of
 sufficient thickness to support the workpieces being positioned. Each of
 the side arms 134, 136 has a proximal end 140 which is coupled with one of
 the side plates 124, 126 of the body 112 of the arm member 16 and a distal
 end 142 which is pivotally coupled with the second end 72 of the boom 14
 at the first and second extension arms 90, 92 via pins 144.
 The transfer arm 138 has a proximal end 146 which is attached to the top
 plate 120 of the body 112 of the arm member and a distal end 148 which is
 pivotally coupled with the arm member cylinder 22. The transfer arm 138,
 as can be best seen in FIGS. 1, 3 and 12, preferably includes two
 plate-like members 150 which are curved or bowed in appearance. Each of
 said curved plates 150 has a bore 152 therethrough at the distal end 148
 of the transfer arm 138 to facilitate the pivotal coupling of the transfer
 arm 138 with the arm member cylinder 22 via a pin 154. The transfer arm
 138 transfers the lateral movement of the arm member 22 into a generally
 vertical arc path traced out by the body 112 of the arm member 16 and in
 turn the workpiece.
 The shaft 18 has a proximal end 156 (not shown) and a distal end 158. A
 portion 160 of the shaft 18 is rotatably received in the bearing 130. The
 shaft is preferably a solid steel bar. The distal end 158 of the shaft 18
 is mechanically coupled with a jig 162. The jig 162 in turn is coupled
 with the workpiece. As seen in FIG. 6, the distal end 158 of the shaft 18
 may be externally threaded 164 and a flange 166 on the jig 162 may be
 internally threaded 168 such that the jig 162 may be threadably coupled
 with the shaft 18.
 The proximal end 156 of the shaft 18 extends outwardly from the rear plate
 118 of the body 112 of the arm member 16 and is coupled with a shaft motor
 170 inside a gear box 172. The shaft motor 170 is preferably a fluid motor
 and is powered by the hydraulic power unit 26. Consequently, the shaft
 motor 170 is connected to the hydraulic power unit 26 via hoses 60.
 The boom cylinder 20 and the arm member cylinder 22 are common hydraulic
 cylinders known in the art. The cylinders each have a housing 174 and a
 rod 176 which is slidably received in the housing 174. Each of the
 housings 174 have a proximal end 178 that includes a flange 180 with a
 bore 182 therethrough to facilitate the pivotal coupling of the cylinder
 20,22 with the appropriate cylinder coupler bracket 42, 96, respectively.
 A distal end 184 of the housing 174 slidably receives a distal end 186 of
 the rod 176. The rod 176 also has a proximal end 188 with a flattened
 tongue portion 190 that has a bore 192 therethrough to facilitate the
 pivotal coupling of the rod 176 of the boom cylinder 20 with the first
 cylinder coupler bracket 94 on the boom 14 or of the arm member cylinder
 22 with the bores 152 in the distal end 148 of the transfer arm 138 of the
 arm member 16. The cylinders 20, 22 are hydraulicly operated and are
 therefore connected with the hydraulic power unit 26 via hoses 60.
 The turntable 24 has a top plate 194 and a bottom plate 196. The top plate
 194 is connected to the bottom end 30 of the column 12 and to a portion of
 the support brackets 64. The bottom plate 196 may be connected to a base
 198 or to a ground or a floor surface 200. The base 198 preferably acts as
 a large counterbalance to prevent the positioner 10 from tipping over when
 a large workpiece is lifted. Alternatively, it is possible for a user to
 omit the base 198 by bolting the bottom plate 196 directly to the floor
 200.
 The turntable is simply a large bearing which permits the top plate 194 to
 freely rotate with respect to the bottom plate 196 even when a large load
 is placed on the top plate 194. The turntable 24 preferably includes a
 slewing gear 202 which includes a plurality of teeth 204 around a
 periphery 206 of the turntable 24. The slewing gear 202 works in
 connection with a turntable motor 208 that permits a user to rotate the
 positioner 10 about a longitudinal axis of the column 12.
 A second embodiment of the positioner of the present invention is
 illustrated in FIG. 5. Because the positioner of the second embodiment
 includes many of the same elements, the elements of the second embodiment
 will be referenced by the numerals given above in connection with the
 first embodiment. However, in the event an element of the second
 embodiment is modified from the similar element in the first embodiment,
 the reference numeral will be followed by a prime mark.
 The main difference between the boom 14' of the second embodiment and the
 boom 14 of the first embodiment is the location at which the boom is
 pivotally coupled with the top end 28 of the column 12'. Instead of the
 boom being pivotally coupled to the top end 28 of the column 12' at its
 first end 70, the boom 14' is pivotally coupled with the top end 28 of the
 column 12' at a location intermediate the first and second ends 70, 72 of
 the boom 14'.
 In this embodiment, the column 12' acts as a fulcrum upon which the boom
 14' pivots. One of the benefits of moving the pivot point between the
 column 12' and the boom 14' towards the midpoint of the boom is a change
 in the element that supports the load placed on the boom when a workpiece
 is lifted. In the first embodiment, as is best illustrated in FIG. 2, when
 a workpiece is coupled with the positioner and the boom 14 is in the
 raised position, the pin 104 in the first cylinder coupler bracket 94 acts
 as the fulcrum and the load and downward force on the boom 14 is
 transferred through the boom cylinder 20 to the cylinder coupler bracket
 42 mounted on the column 12. This arrangement, especially when an
 extremely heavy workpiece is being positioned, places a large amount of
 stress on both the boom cylinder 20 and the cylinder coupler bracket 42.
 In the second embodiment, however, because the point where the boom
 attaches to the column is moved inward on the boom 14', the load and
 downward force placed on the boom 14' is directed through the pins 74 and
 right down through the column 12'. As a result, the column 12' directly
 supports the load and a considerable amount of stress is removed from the
 cylinder coupler bracket 42 and the boom cylinder 20 in the second
 embodiment.
 As can be seen in FIG. 5, the boom 14' has also basically been inverted. As
 a result, the boom 14' does not have a bottom wall 78 like the boom 14 of
 the first embodiment but instead has a top wall 210 upon which the second
 cylinder coupler bracket 96 is mounted. The first cylinder coupler bracket
 94 may be either moved to the first end 70 of the boom 14' or may be
 removed. If the first coupler bracket 94 is removed from the boom 14', the
 proximal end 188 of the boom cylinder 20 is coupled with the first end 70
 of the boom 14' via a pin 212 through the bores 76 in the first end 70 of
 the boom 14'. Additionally, as a result of the change in the point at
 which the boom cylinder 20 couples with the boom, the cylinder coupler
 bracket 42 on the column 12' is located on the back wall 36 of the post 32
 instead of on the front wall 34 as in the first embodiment.
 Other changes which may be incorporated in the second embodiment include
 replacing the shelf 50 on the first side wall 38 that supports the
 hydraulic power unit 26 with a bracket 214 projecting outwardly from the
 back wall 36 of the column. By incorporating this change, the hydraulic
 power unit 26 can be further moved out of the way while at the same time
 functioning as a counterbalance. A still further change in the second
 embodiment is the position of the plate 66 with respect to the side walls
 80, 82 of the boom 14'. In the first embodiment, the first end 70 of the
 boom 14 was located between the plates 66. In the second embodiment,
 however, the plates 66 are positioned within the opening defined by the
 first and second side walls 80, 82 and the top wall 210.
 One of the modifications that can be made to the positioner of the present
 invention is the inclusion of a linkage 216, as illustrated in FIG. 4. The
 linkage 216 is preferably a Y-shaped bar member having a first end 218 and
 a second end 220. The first end of the linkage has a bore 222 through
 which the pin 48 passes when the first end of the linkage is positioned
 between the pair of flanges 44 of the cylinder coupler bracket 42. The
 second end 220 of the linkage 216 includes a pair of spaced apart flanges
 224 similar to the flanges 44 of the cylinder coupler bracket 42 and
 between which the flange 180 of the housing of the boom cylinder 20 is
 positioned. The boom cylinder 20 is then coupled with the second end 220
 via a pin 226 that passes through bores 228 in the flanges 224. As seen in
 FIG. 4, when the linkage 216 is used in the manner illustrated, a block
 230 is positioned below the second end of the linkage and supports the
 linkage and boom cylinder combination during use. By using the linkage 216
 in the manner described, a user can change the height through which the
 second end of the boom travels without having to purchase multiple boom
 cylinders 20 of varying length.
 Another method of varying the height of the path through which the second
 end of the boom travels is illustrated in FIG. 9. While the method
 illustrated in FIG. 4 permits the user to lower the path through which the
 second end of the boom travels during use, FIG. 9 illustrates a method a
 user may use to raise the path through which the second end of the boom
 travels when compared to the arrangements of FIGS. 1 and 5 which do not
 incorporate the use of a linkage. In this method, a second linkage 232 and
 a second cylinder coupler bracket 234 are added. This arrangement raises
 the location of the proximal end 178 of the boom cylinder 20 and in turn
 raises the relative positions of the boom during use.
 Other modifications to the positioner that are within the scope of the
 present invention are illustrated in FIGS. 7 and 8. FIG. 7 illustrates a
 positioner that has been modified to include a telescoping column 12". The
 column 12" has an inner piece 236 and an outer piece 238. The inner piece
 236 is stationary and is rigidly secured at a bottom end 240 to the top
 plate 194 of the turntable 24. The outer piece 238 is slidably received on
 the inner piece in telescoping fashion. The column 12" also includes a
 column cylinder 242 that is located inside the mating pieces 236,238. Just
 like the other hydraulic cylinders 20,22, the column cylinder has a
 housing 174 with a proximal end 178. The proximal end 178 of the housing
 is coupled to the turntable 24 via a first coupler bracket 244. The column
 cylinder also has a rod 176 with a proximal end 188. The proximal end of
 the rod is coupled to the outer piece 238 via a second coupler bracket
 246. The boom cylinder may then be used to raise and lower the outer piece
 with respect to the base 198 and, because the boom 14 and the boom
 cylinder 20 are coupled with the outer piece, the boom cylinder raises and
 lowers the relative height of the workpiece.
 FIG. 8 illustrates a positioner that has been modified to include a
 telescoping boom 14". As with the telescoping column 12", the telescoping
 boom 14" has an inner piece 248 and an outer piece 250. The telescoping
 boom 14" also has an interior boom cylinder 252. The proximal end 178 of
 the housing of the interior boom cylinder 252 is coupled to the stationary
 inner piece 248 via a coupler bracket 254. The coupler bracket 254 can be
 located on a divider wall 256 in the inner piece. The proximal end 188
 (not shown) of the rod 176 is then coupled to the outer piece 250 and the
 interior boom cylinder can be used to move the workpiece toward and away
 from the column 12.
 In use, a user attaches a workpiece to be positioned to the jig 162 located
 on the distal end 158 of the shaft 18. By extending and retracting the rod
 176 of the boom cylinder 20, the user can move the workpiece through a
 large and generally vertical arc. By selectively extending and retracting
 the rod 176 of the arm cylinder 22, the user can also move the workpiece
 through a smaller generally vertical arc as the arm member pivots around
 the second end 72 of the boom 14. Additionally, the user may rotate the
 workpiece 360.degree., both clockwise and counterclockwise, about the
 longitudinal axis of the shaft 18. Further still, by rotating the column
 12 about its own generally vertical axis via the turntable 24, the user
 can move the workpiece through a large generally horizontal arc. Even
 further, if the positioner incorporates the extendable column and/or the
 extendable boom illustrated in FIGS. 7 and 8, respectively, the user may
 move the workpiece up and down and/or in and out, respectively.
 As can be seen, the positioner 10 is uniquely adapted to permit a user to
 move a workpiece through an infinite number of orientations to facilitate
 the welding or otherwise working on the workpiece in a safe manner.
 Additionally, because of the ease at which a user can change the
 orientation of the workpiece, the positioner makes the performing of
 common tasks in the manufacturing process more ergonomical as the user can
 move the workpiece to the proper height and orientation.
 From the foregoing it will be seen that this invention is one well adapted
 to attain all ends and objects hereinabove set forth together with the
 other advantages which are obvious and which are inherent to the
 structure. It will be understood that certain features and subcombinations
 are of utility and may be employed without reference to other features and
 subcombinations. This is contemplated by and is within the scope of the
 claims.
 Since many possible embodiments may be made of the invention without
 departing from the scope thereof, it is to be understood that all matter
 herein set forth or shown in the accompanying drawings is to be
 interpreted as illustrative of applications of the principles of this
 invention, and not in a limiting sense.