US3388657A - Flat truss press - Google Patents

Description

June 18, 1968 J. c. JUREIT FLAT TRUSS PRESS 6 Sheets-Sheet 2 I Filed March 2, i966 l i I l I I I i. Q .w.mN WW QMN 9 New INVENTOR. TOHN CHLVIN S RE (T iazwafi ATTORNEYS.

June 18, 1968 J. c. JUREIT FLAT TRUSS PRESS 3 Sheets-Sheet 15 Filed March 2, 1966 S un QvR

mmvrozc 3'OHN ALV N I'UREIT BY 34.84 19% ATTORNEYS.

United States Patent "ice 3,388,657 FLAT TRUSS PRES John Calvin Jureit, Miami, Fla, assignor to Automated Building Components, 1110., Miami, Fla, a corporation of Florida Filed Mar. 2, 1966, Ser. No. 531,132 4 Claims. (Cl. 100-208) ABSTRACT OF THE DISCLOSURE The flat truss press comprises a plurality of longitudinally spaced press units, each comprising transversely spaced press head. The press units are adjustably mounted on a longitudinally extending base at selected positions therealong. The press heads are mounted on a frame for movement toward and away from each other whereby various sizes and arrangements of trusses can be placed on the frame below the press platens of the press heads. Press actuation and relative transverse movement between the press heads is accomplished by fluid actuated cylinders, while adjustable longitudinal movement of each press unit along the base is accomplished by means of a sprocket journaled in each press unit and engaging a chain fixed to the base.

The present invention relates to an improved press for fabricating fiat trusses.

In recent years the building trades have shown a marked trend toward prefabrication. Various portions of frame homes, such as trusses have thus been preassembled at the factory and shipped to building sites. This prefabrication itself has undergone an evolution from hand nailing and bolting of trusses to the vastly improved method of construction which was made possible by the advent of structural butt joints formed with unitary connector plates of the type described in Patent No. 2,877,520.

In previous fabrication techniques which utilized truss presses, wooden structural elements consisting of elongated chords and cross members were assembled on a frame or jig which held these elements in proper position with connector plates mounted on the opposite sides of the truss at the butt joints. Thereafter, as described in Patent No. 2,877,520 the assembled wooden elements and connector plates were subjected to pressure to thereby form the completed truss. A press capable of providing the foregoing action is shown in Patent No. 3,079,607.

However in the past a truss press was generally set up to fabricate a particular size and type of truss. However when a dilferent type or size of truss was to be built, a large amount of labor was required to prepare the press for making the new trusses. In addition, in previous truss presses, it was relatively diflicult to remove the truss after the truss elements had been secured to each other because the machine elements tended to obstruct such removal. This again contributed toward inefficiency in truss fabrication with the attendant increase in cost of manufacture. It is with the overcoming of the foregoing shortcomings encountered in previous truss making techniques that the present truss press is concerned.

It is accordingly one object of the present invention to provide an improved highly versatile truss press which 3,388,657 Patented June 18, 1 968 can be rapidly modified to make various sizes and configurations of trusses in an extremely simple and expedient manner.

Another object of the present invention is to provide an improved truss press having the parts so arranged that a completed truss can be removed from the press in a simple manner without being obstructed by the press elements. Other objects and attendant advantages of the present invention will be readily perceived hereafter.

The present invention relates to an improved truss press having a plurality of press units spacedly mounted on an elongated base. Means are provided for moving each of the press units lengthwise of the base to vary the spacing therebetween to thereby space the press units by an amount equal to the spacing between the cross members of the truss. In addition, each press unit includes a pair of spaced press heads which can be moved toward and away from each other in a direction substantially perpendicularly to the longitudinal axis of the base to vary the spacing therebetween. This permits them to be set up to receive cross pieces of different lengths. A hydraulic system is provided for actuating all of the press heads simultaneously to drive connector plates into the assembled truss components. Thereafter the press heads of each press unit are caused to move apart to permit the completed truss to be removed without obstruction by the press heads. The present invention will be more fully understood when the following portions of the specification are read in conjunction with the accompanying drawings wherein:

FIG. 1 is a plan view of the improved truss press of the present invention;

FIG. 2 is a side elevational view of the truss press of FIG. 1;

FIG. 3 is a view taken substantially along line 3-3 of FIG. 1 and showing various components of a truss press unit;

FIG. 4 is a view taken substantially along line 44 of FIG. 3;

FIG. 5 is a fragmentary plan view of the truss press unit of FIG. 4;

FIG-6 is an enlarged view of a portion of FIG. 3 showing the manner in which each truss press unit is mounted for movement on the truss press base;

FIG. 7 is a view taken substantially along line 7--7 of FIG. 4 and showing the mechanism used for locking each truss press unit in position;

FIG. 8 is a view taken substantially along line 8--8 of FIG. 7;

FIG. 9 is a plan view of a truss of the type fabricated by the improved truss press of the present invention; and

FIG. 10 is a side elevational view of a connector plate used in the press.

In FIGURE 9 a fiat truss 10' of the type which is fabricated by the improved press 11' of the present invention is shown. Truss 10 consists of elongated chords 11 and 12 which are joined by spaced cross members 13 and by diagonal members 14, which extend between the opposed chords and adjacent cross members 13. Butt joints, not numbered, are formed at the junctions of elements 12, 13 and 14 and at the junctions of elements 11, 13 and 14. It is at these butt joints that connector plates 15 are driven into the adjacent butted members on op- 3 posite sides of the truss to hold the truss in assembled condition.

Each connector plate 15 consists of a substantially rectangular base 16 from which are struck a series of slender elongated nail-like teeth 17. Connector plates 18 of a different size may be used at the end locations for joining two butted members. It will be appreciated that the connector plates 15 are located on opposite sides of the truss in opposition to each other at the butt joints, as will become more apparent hereafter.

In order to fabricate a truss such as 10', press 11' is used. Essentially press 11' consists of a plurality of press units 1 through 10, inclusive, which are mounted for movement along the longitudinal axis of base 19 to permit the fabrication of trusses of different lengths and having dilferent spacings between cross braces 13 thereof. Each press unit 1-10 includes a pair of spaced press heads which are movable relative to each other in a direction transverse to the longitudinal axis of base 19 to adjust the spacing therebetween.

The improved truss press 11' includes a base .19 consisting of elongated channels 20 and 2]. (FIGS. 1, 3 and which are connected by suitable welding or the like through cross struts 22. An angle member 23 (FIGS. 3 and 5) is welded to top plate 24 of channel 20 so that apex 25 points upwardly. Angle 23 extends throughout the length of channel 20. Leg 26 (FIG. 5) of press unit 27 is essentially a vertical plate member with its lowermost portion notched at 28 for complementary mating engagement with the outer surfaces of legs 29 and 30 of angle 23. The foregoing connection between leg 26 and angle 23 permits longitudinal sliding movement therebe tween, while holding leg 26 on channel 20. In addition to leg 26 of press unit 10, an opposite leg 27 is provided (FIG. 5), the lower portion of which is square for sliding engagement on top surface 31 of channel 21.

A frame 32 is mounted on plates 26 and 27 and consists of parallel channels 33 and 34 which are connected to each other by I- beams 35 and 36. Bar 37 extends between facing webs (not numbered) of channels 33 and 34, and inverted U-shaped channel 38 is mounted on bar 37. The opposite ends of channel 38 and of bar 37 are secured, as by welding, to channels 33 and 34. An additional frame 39, consisting of parallel plates 40 and 41 connected by end plates 42 and 43, is provided and is secured, as by welding, to the upper legs of channels 33 and 34. Flanges 44 and 45 extend downwardly from plates 40 and 41, respectively, and mount bars 46 and 47, respectively, on their inner faces.

A press head 47 is mounted in opening 48 defined by plate 38 of channel 38, and by plates 40, 41 and 42. Press head 47 includes a base plate 49 which extends across plates 40 and 41. Plate 49 (FIG. 5) has apertures 50 and 51 therein which receive screws 52 and 53, respectively. As can be visualized from FIGURE 5, base plate 49 can be moved along plates 40 and 41 when screws 52 and 53 are removed from apertures 54 and 55. After aperture 50 is aligned with any one of apertures 54 in plate 40 and aperture 51 is aligned with any one of apertures 55 in plate 41, screws 52 and 53 are inserted to secure plate 49 in position. Plate 49 serves as the base for supporting a connector plate 15 and a portion of a chord of a truss, as will become more apparent hereafter. Press head 47 also includes an additional plate 56 (FIG. 3) which is movably located underneath base plate 49 and extends between flanges 44 and 45 (FIG. 4) depending downwardly from plates 40 and 41. The ends of plate 56 provide a square fit with flanges 44 and 45, which causes plate 56 to act as a key for guiding a portion of press head 47 for rectilinear movement along plates 40 and 41 during retraction thereof.

Secured to the underside of plate 56, as by welding, are lower legs 57 and 58 of C- frame members 59 and 68, respectively, having upper legs 61 and 62, respectively. C-frame members 59 and 60 are connected to each other by horizontal plate 63, FIG. 4, which has its opposite ends secured to legs 61 and 62 by welding. Flanges 64 and 65 of hydraulic motor 66 have rods 67 extending therethrough, said rods also extending through aligned apertures, not shown, in plate 63. Nuts 68, 69 and 70 are secured to rods 67, as shown, to firmly mount hydraulic motor 66 on plate 63. The piston (not shown) Within hydraulic motor 66 is connected to head 71 through shaft 72, head 71 in turn mounting plate 73 which moves up and down when motor 66 is actuated. A pin 74 (FIG. 3) extends rearwardly from piston head 71 toward the central portions of C-frames 59 nad 60 and is received within slot 75 of plate 76 having its opposite edges welded to the central portions of C- frames 59 and 68. Pin 74, by virtue of traveling in slot 75, guides plate 73 upwardly and downwardly in a rectilinear path.

As can be seen from FIGURE 3, a portion of press head 47 can move between the dotted and solid line positions. In the dotted line position, plate 73 overlies a chord lying on plate 49. When plate 73 of press head 47 is in the solid line position, it will be moved away from a chord lying on plate 49. The press head is moved to its solid line position to permit the chord to be unobstructed for ease in removal. In order to achieve the foregoing, a channel 77 is secured to the underside of plate 49 which, as described above, is fixedly attached to plates 4t) and 41. A piston rod 78 has its end secured to channel 77 by nuts 79 and 80. A cylinder 81 has its head 82 secured to channel 83 through which piston rod 78 extends with a sliding fit. Channel 83 is secured to C- frarne legs 57 and 58. Since the end of piston rod 78 is attached to fixed channel 77 it will readily be appreciated that when fluid pressure is admitted to the right of piston 84, cylinder 81 will move to the right to move C-frames 59 and 60 to the solid line position shown in FIGURE 3. To facilitate the above described rectilinear movement of plate 73, rollers 86 are mounted on plate 87, respectively having their upper edges secured as by welding to the lower surface of plate 56. Roller 86 roll on bars 46 and 47 (FIG. 4).

Press head 10 has a pair of clamps 89 and 90 mounted thereon for securing a chord, such as 11, to this press head. Clamp 89 includes a base 91 which is secured to angle 92 mounted on the top of plate 49. A member 93 has pin 94 mounted at its lower end so that member 93 may pivot in member 91. This permits the top elongated plates 95 and 96 of clamp member 89 to pivot in a clockwise direction about the axis of pin 94 in FIGURE 3 to thereby move out of overlying relationship relative to plate 49 to permit a chord, such as 11, to be placed with its rear edge 96 (FIG. 9) against the vertical edge of angle 92. Mounted at the end of plates 95 and 96 remote from pin 94 is a pin 98 which pivotally supports shoe 99 having lever 100' attached thereto. After the chord .11 has been placed in abutting relationship to the vertical side of flange 92, lever 100 is rotated to move shoe 99 into engagement with edge 100 of chord 11 because shoe 99 is eccentrically mounted on pin 98. It is to be noted that clamp 90 is of the same construction as clamp 89 and therefore a detailed description thereof has been omitted. However, it is to be noted that angle 92' (FIG. 5) of clamp 90 is identical to angle 92 and also has a vertical edge 91' which also serves as an abutment for an edge of chord 11.

A chord such as 11 is clamped on plate 49. Furthermore, it is to be noted that only the end press unit 10 has clamps 89 and 90 thereon for clamping the end of a chord such as 11. The remainder of the press units 1 through 9 do not have this construction nor do they need it. It is to be noted at this point, that chord 1]. lies not only on plate 49 of press unit 10 but also lies on analogous plates 101 through 109, inclusive, of press units 1 through 9, respectively. At this point it is also to be noted that press units 1 through 9 may be identical in all respects to press unit 10 except for the clamping mechanisms 89 and 99'.

Frame 32 also contains a window 110 in which a press head 111 is mounted in opposition to press head 47. Press head 111 includes a base plate 112 having its outer edges overlying plates 4%) and 41. Screws 113 (FIG. 5) fit through apertures (not numbered) in plate 112 and are received in selected apertures 114 in plate 41 and apertures 115 in plate to thereby locate base plate 112 on the press unit 10. Plate 112 is affixed to the remainder of press head 111 through plate 116 (FIG. 3) having opposite edges which fit between the downwardly extending flanges 44 and depending from plates to and 41. The edges of plate 116 guide the remainder of the press head 111 for rectilinear movement, as would be required when the position of base plate 112 is being adjusted. Secured to the underside of plate 116, as by welding, are the lower legs 117 and 113 of C-frames 119 and 1213, respectively, the central portions of which are connected by plate 121 having slot 122 therein for receiving pin 123 attached to cylinder head 124 to guide the latter for rectilinear movement. The upper legs 125 and 126 of C-frames 119 and 1219 are connected by plate 127 on which fluid pressure motor 128 is mounted. This motor contains a piston therein (not shown) which is attached to head 124 which in turn mounts plate 129. Motor 128 is mounted on plate 127 in the same manner as motor 66 is mounted on plate 63 and therefore a detailed description is not deemed necessary. Rollers 119 are mounted on plates (not numbered) extending downwardly from plate 115. These rollers ride on bars 46 which are analogous to bars 46 and 47 associated with window 43.

At this point it is to be noted that a detailed description has been made of press unit 19. It is to be again noted that each of press units 1 through 9 are of identical construction in all material respects except for clamps 89 and 91 which are not required on each of the press units 19.

In FIGURE 1, press units 1 through 11) are shown as being substantially equidistantly placed. This is the required orientation to fabricate a particular type of truss 10 such as shown in PEG. 9. However, each of the press units 1 through 19 is movable on base 19 to make the machine capable of producing a truss having any desired spacing of the cross braces 13. To this end, a shaft 130 (FIG. 3) has opposite end portions journalled in legs 26 and 27 of the press unit 113. Keyed to said opposite end portions are gears 131 and 132 which are in mesh with chains 133 and 134, respectively, welded to base channels 21) and 21, respectively. Heads 135 and 136 are located at opposite ends of shaft 130 for receiving a suitable wrench or the like for rotating shaft 130. It will readily be appreciated that whenever shaft 131 is rotated, gears 131 and 132 will engage successive portions of the chains with which they are in mesh to thereby cause the press unit to move along the longitudinal axis of base 19. Whenever press unit 11 has been moved to its desired position, a pin 137 which is mounted for threaded movement in block 138 is moved so that the end 139 thereof enters the space between two adjacent teeth of gear 132. In order to provide a fineness of adjustment another pin 137 which may be identical in all respects to pin 139, and which is mounted in block 138 in the same manner, may be spaced from pin 139 a distance which is an odd multiple of one-half the pitch of teeth of gear 132. Thus, the position of press unit 16 may be adjusted on base 19 to the nearest one-half of the pitch of the teeth on the gears 132 or 131. While this adjustment has been described only with respect to press unit 10, it will be appreciated that the identical structure is provided on each of press units 1 through 9. Thus, each of the press units may be adjusted longitudinally of base 19 so that they can be ultimately spaced from each other as is required by the distances between cross braces 13 of a particular truss which is to be fabricated.

As noted above, the base plates 49 and 112 of the press heads 47 and 111 of press unit 10 may be moved relative to each other to accommodate any particular length of cross brace 13. Thus, there are two adjustments which must be made in order to set the press units 1 through 10 for fabricating trusses. These, as noted above, are the longitudinal spacing between the press units 1-10 on base 19 and, secondly, the spacing between the press heads 47 and 111 on each of the presses.

After the press units 1 through 10 have been spaced relative to each other and after the press heads such as 47 and 111 on each of the units have been spaced from each other, the press is ready for operation. A connector plate 15 is mounted on plate 49 of press unit 47 with the plate portion 16 lying on plate 49 and teeth 17 pointing upwardly. A suitable locating mechanism may be placed on plate 49, such as a pin or pins extending upwardly from plate 49 which are received in suitable openings in plate 16. Similar connector'plates 15 are placed on each of plates 191 through 169 (FIG. 1) with the teeth 17 pointing upwardly. The connector plates on each of plates 101 through 169 are located in a predetermined position in the same manner as noted above relative to plate 49. Thereafter connector plates, such as 15, are placed on plate 112 of press head 111 and located by suitable pins or the like. Connector plates are then placed on plates 146 through 148, inclusive, which are associated with press units 1 through 9, inciusive, respectively, and are analogous to plates 112 of press head 111. These additional connector plates 115 are located by means of suitable pins or the like so that they occupy predetermined positions on the plates on which they are mounted with their spikes 17 pointing upwardly.

A chord such as 11 of FIGURE 9 is placed so that it lies on the spikes of each of connector plates 15 mounted on each of plates 49 and 102 through 109 inclusive with the rear edge 96 of chord 11 abutting the vertical leg 92 of the channel on plate 49 and analogous vertical legs or stops on each of the other plates 101 through 109. Thereafter, clamps S9 and 90 are actuated to lock chord 11 in position.

It will readily be seen therefore that chord 11 rests on a portion of each connector plate mounted on each of plates 49 and 161 through 109. Then a chord such as 12 is placed so that it runs parallel to chord 11, but is mounted on each of the connector plates located on plates 112 and plates 140448 of press units 1 through 10. Thereafter, cross braces 13 are mounted at each of the press units 1 through 10 so that, for example, one cross brace 13 straddles the distance between plates 49 and 112 at press unit 10 and has its ends resting on the connector plates 15 mounted on plates 49 and 112. A cross brace 13 is thereafter mounted in the same relationship on each of press units 1 through 9. Thereafter, diagonal braces 14 (FIG. 9) are also placed in position. After all the parts have been assembled in the foregoing manner, clamps such as 151 (FIG. 5) are ac tuated to hold the chords 11 and 12 and the cross braces 13 and 14 in assembled relationship. More specifically, each clamp 150 includes a head 151 which abuts the edge 152 of chord 12. Clamps 159 are each actuated manually to lock the truss in its assembled position. However, they release automatically after the connector plates 15 are driven into the truss. It is deemed unnecessary to go into specific detail of the construction of each of clamps 150 associated with each of press units 1 through 10 inasmuch as this is completely described in US. Patent No. 3,238,867 dated Mar. 8, 1966, in the names of Jureit and Bowman.

After the truss has been assembled and locked into position in the above described manner a connector plate 15 is then placed in opposition to each connector plate 15 which was originally placed on the various press units. In other words, a connector plate such as 15 is placed with its teeth 17 pointing downwardly in overlying relationship to the butt joints, as shown in FIGURE 9. If desired, these connector plates may be magnetically held by suitable magnets on the undersides of press head plates, such as 73 and 129 of press heads 47 and 111, respectively.

As can be seen from FIGURE 1 a pad 152 is provided having a motor 153 mounted thereon which is coupled to pump 154 through linkage 155. Pump 154 in turn is in communication with a source of hydraulic fluid, not shown. Conduit 156 is in communication with pump 154 through conduit 17%, valve 158 and conduit 157. Branch conduits 156' are in communication with conduit 155. One branch conduit 156 is in communication with the upper portion of cylinder 66 (FIG. 3) and other branch conduits 156' are in communication with each of the corresponding portions of the analogous cylinders mounted on each of press units 1 through 9. As can be seen conduit 157 is in communication with pump 154 through valve 158 and conduit 17%. Branch conduit 157 is in communication with conduit 157 and with the upper portion of cylinder 128 (FIG. 3). Other branch conduits 157 are associated with the cylinders which are analogous to cylinder 128 on press head 111. A suitable valve 158 effects communication between pump 154 and conduits 156 and 157 so as to cause the upper portions of cylinders 66 and 128 to be pressurized to thereby drive the pistons therein (not shown) downwardly and cause the plates 73 and 129 and analogous plates on all of the other fluid pressure motors to move downwardly to thereby drive the connector plates 15 into the assembled chords 11 and 12 and the cross braces 13 and 14. It will readily be appreciated that the pressure provided by the press heads causes both the upper and lower connector plates to be driven into the assembled wooden. structural members.

After the foregoing has been effected, valve 158 is actuated to relieve the pressure from conduits 156 and 157 and supply pressurized fluid to conduits 159 and 166. Conduit 159 is in communication with conduits 159 (FIG. 3). Each conduit 159' is in communication with the lower portion of cylinder 66 and the analogous cylinders mounted on press units 1 through 9. Conduit 1st) is in communication with conduits 160' (FIGS. 1 and 3), each of which is in communication with all of the cylinders analogous with cylinder 128. The admission of pressurized fluid to the lower portions of all of the cylinders analogous to 66 and 128 will cause the pistons therein to ride upwardly to thereby move the plates 73 and 129 back to the position shown in FIGURE 3 after they have performed their connector plate driving functions.

If the pressure head 47 and the analogous pressure heads on press units 1-9 should occupy the position shown by the dotted line of cylinder 66 in FIGURE 3 after the above described connector plate driving operation has been effected, the only way in which the truss could be removed from the truss press 11' Would be by slipping it out laterally across the end 22 of the press. This would be an extremely tedious and ineflicient operation. Accordingly, the press includes a valve 162 coupled to pump 154 for selectively admitting pressurized fluid to cylinder 81 to the right of piston 84- through conduit 163 (FIG. 3) which is in communication with conduit 164 leading from valve 162. It is to be noted at this point that each of press units 1 through 9 has a cylinder analogous to cylinder 81. The admission of pressurized fluid to the right of piston 84 will cause the entire pressure head 47, except plate 4h, to move to the solid line position in FIGURE 3 to therefore move plate 73 out of overlying relationship relative to the chord 11. It is to be noted that this same action occurs in each of the other press units 1 through 9 so that they will all be retracted. Thereafter, the completed truss can be lifted from all of the press units by merely lifting chord 11 and tilting it upwardly and toward the left in FIGURE 3 so that it clears all of the plates analogous to 73. This direction is shown by arrow 1:15 in FIGURE 3. Once this clearance has been effected, the completed truss it) can be lifted from the machine. It will also be appreciated that compressed air may also be utilized instead of hydraulic fluid for moving press heads 47 back and forth. In this case it is merely necessary to substitute a source of compressed air for the source of pressurized liquid but the same conduits described above may be used.

After another chord, such as 11, has been placed on plate 49 and plates 131-189, valve 162 is manipulated to cause pressurized fluid to enter conduit 166 which is in communication with conduit 167 (FIG. 3) to the left of piston 84 in cylinder 81. This will cause the entire press head 47 excluding plate 49 to move to the left in FIGURE 3 to thereby occupy its dotted line position with plate 73 thereof in overlying relationship relative to a chord such as 11. Conduits such as .167 are associated with each of the cylinders such as 81 associated with all of the press heads analogous to 47 so that they all move in unison upon the actuation of valve 162..

While not specifically shown in the drawings, it will be appreciated that suitable guides may be used for properly aligning and locating cross members 13. These guides may be pairs of pins which straddle members 13 and which extend from plates 49 and .112 on press unit 10 and from the analogous plates on the other press units. In addition, if desired, suitable guides may be provided for diagonal braces 14. Also, while not shown, an abutment may be provided for the end of chord .12 to insure its proper positioning.

It can thus be seen that the present invention is manifestly capable of achieving the above enumerated objects and while preferred embodiments of the present invention have been disclosed it will readily be appreciated that it is not limited thereto but may be otherwise embodied within the scope of the following claims.

What is claimed is:

1. A truss press comprising an elongated longitudinally extending support, a plurality of press units spacedly mounted along said support, means for moving said press units along said support to adjust the longitudinally spacing between. said press units, means for restraining said press units against movement in their adjusted positions, each of said ress units including a frame mounted on said support, first and second press heads spaced transversely from each other on said frame, said first and second press heads including a press platen, said press heads each including a C-frame member having a fluid actuated piston and cylinder mounted on the upper leg thereof, said press platens being mounted on the ends of said pistons for vertical reciprocation therewith, means for adjustably spacing each of said press heads relative to each other in a transverse direction including roller means and guideways, and means mounting the lower legs of said C-frame members for transverse movement along said frame.

2. A truss press according to claim 1 wherein said frame has depending transversely spaced legs mounting the same on said support, said moving means including a chain and sprocket assembly, such chain being substantially coextensive with said support, means retaining said chain against longitudinal movement, each of said press units having a sprocket journaled on one of its'legs and engaging said chain whereby rotation of said sprocket moves the associated press unit along said support, and a pin carried by said one leg and releasably engageable with the associated sprocket to hold said press unit against movement in a longitudinally adjusted position.

3. A truss press according to claim 1 including means for moving said first press head away from said second press head after the completion of a pressing operation to thereby remove said first press heads from obstructing relationship relative to a completed truss, and including a fluid operated piston and cylinder engaging between the lower legs of said C-frame members of at least one of said press heads carried by each of said press units.

4. A truss press according to claim 3 including conduit means connecting said piston and cylinder in each of said press heads in parallel and selectively operable means 9 to actuate said piston and cylinder to reciprocate said 259,902 6/1882 Muller 100--231 X 2,996,721 8/1961 Black 227-152 3,069,684 12/1962 Moehlenpah et a1. 227152 10 Black 227-152 X Sanford 227-152 X Adams et a1 100-231 X Jureit et a1. -2 100214 Anderson et a1 100-214 BILLY J. WILHIT E, Primary Examiner.

Images