US3599562A

US3599562A - Apparatus for fabricating multiple type truss members

Info

Publication number: US3599562A
Application number: US868464A
Authority: US
Inventors: Ralph W Hutchens Sr
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-10-22
Filing date: 1969-10-22
Publication date: 1971-08-17
Anticipated expiration: 1988-08-17

Abstract

A plurality of power-actuated press devices are adjustably supported for movement to desired positions in which the timber components of a truss are positioned with the juncture of one or more timber elements being supported by the press devices which upon actuation impress nail plates into the various timber members for joining the timber members to each other; all of the timber members are positioned in the final form of the truss with all of the press assemblies being simultaneously actuated to provide the finished truss. Changeover from one form of truss assembly to another is enabled by electric motor drive means connected to the press assemblies by drive transmission chains for automatically positioning the press devices in accordance with the nature of the truss to be assembled. Another aspect of the invention resides in the particular nail-plate press devices in which a single power source provides the movement necessary for opening the press and for impressing the nail-plates in the timber members.

Description

Ralph W. Hutchens, Sr.

P.O. Box 128, Toano, Va. 23168 [21 Appl. No. 868,464

[22] Filed Oct. 22, 1969 [45] Patented Aug. '17, 1971 [72] Inventor [54] APPARATUS FOR FABRICATING MULTIPLE TYPE TRUSS MEMBERS 25 Claims, 19 Drawing Figs.

[52] U.S. Cl 100/100, 100/226, 100/231, 100/233, 100/269, 100/289, 227/152 [51] Int. Cl B30b 15/00 [50] Field of Search 227/152;

IOO/DIG. 13, 100, 231, 226, 233, 289, 269, 208

[56] References Cited UNITED STATES PATENTS 3,068,483 12/1962 Moehlenpah et al. 227/152 3,100,301 8/1963 Black 227/152 X 131334 W1 i, !?!-:;-:;:----r111-;11-:- l9.Q/29

" lee 3,460,465 8/1969 McGlinchey ABSTRACT: A plurality of power-actuated press devices are adjustably supported for movement to desired positions in which the timber components of a truss are positioned with the juncture of one or more timber elements being supported by the press devices which upon actuation impress nail plates into the various timber members for joining the timber members to each other; all of the timber members are positioned in the final form of the truss with all of the press assemblies being simultaneously actuated to provide the finished truss. Changeover from one form of truss assembly to another is enabled by electric motor drive means connected to the press assemblies by drive transmission chains for automatically positioning the press devices in accordance with the nature of the truss to be assembled. Another aspect of the invention resides in the particular nail-plate press devices in which a single power source provides the movement necessary for opening the press and for impressing the nail-plates in the timber members.

PATENTED AUG] 7 I971 SHEET 1 OF 8 INVI'JN'I UH. QALPH W. HUTCHIN5,$2-

ATTORNEYS PATENTEUAUGI'IISYI 3 599,5 2

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msagmkfimmi PATENTEDAusmsn 3.599562 SHEEI 5 [IF 8 PATENIED nus: 7 an SHEET 7 [1F 8 i Ag-te INVEN'IOR. QALPH \N. Hu-rcHeNs,S2-

BY- masou lwwwt A'I'TORNICYS APPARATUS FOR FABRICATING MULTIPLE TYPE TRUSS MEMBERS BACKGROUND OF THE INVENTION This invention is in the field of fabrication devices and is particularly directed to means for enabling the fabrication of wooden truss members of varying designs. Such truss members are formed of timber components which are. joined together by nail plates to provide a rigid unitary truss construction. While many of the prior known devices have been adequate in certain respects, they have suffered from a number of defects which have, until this invention, remained unsolved.

For example, many of the prior known devices join the various timber elements at each individual juncture separately one after the other as the junctures are brought into position in a nail-plate press. However, the instant invention is a vast improvement over devices of this type in that all of the timber junctures are simultaneously connected by individual press elements located at each juncture. Consequently, the resultant truss members are uniformly and accurately provided.

An additional advantage of this invention is that it does not require the large amount of space necessary if a truss member being formed is to be manipulated and maneuvered into various positions for connecting the timber junctures.

Other prior art devices have employed individual nail-plate press members for impressing nail-plates at each timber juncture. However, the nail-plate press members employed by the prior art devices have been both cumbersome and expensive to manufacture and maintain. The instant invention, on the other hand, provides a uniquely simplified nail-plate press member which is economical to manufacture, maintain and operate. Moreover, one embodiment of the press member employed in this invention does not require the employment of auxiliary pneumatic or hydraulic pressure means for operation.

in that it is driven solely by elect c motor means.

Additionally, none of the prior known devices previously used in assembling truss members have employed easily adjustable motor driven means for automatically varying the position of the individual nail-plate press devices to enable a changeover from one truss design to another. The present invention, on the other hand, enables such changeover in a very rapid manner and results in a great savings in labor and a dramatic increase in efficiency over any of the prior known devices.

SUMMARY OF THE INVENTION It is the primary object of this invention to provide a new and improved means for assembling and connecting the timber elements of wooden trusses.

Obtainment of the object of this invention is enabled through the provision of a plurality of fixed rail members and a plurality of shiftable rail members for supporting individual nail presses capable of embedding nail-plates in timber members to be joined. Both the fixed and the shiftable rail members support movable carriage means on which individual nailplate press devices are mounted. Automatic motor driven chains connected to the shiftable rail members and to the carriage serve to position each nail-plate press in any desired position in accordance with the nature of the truss to be fabricated.

Each nail-plate press includes an axially reciprocable rod on the interior of a main cylinder column driven either by an electric motor or by a piston. Downward movement of the rod from an upper limit position serves to pivot a C-shaped frame having a movable platen on its upper end into position above timber elements positioned on a fixed platen on the upper end of the cylinder and then subsequently moves downward vertically to impress nail-plates into the upper and lower surfaces of the timber members. DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a portion of a preferred embodiment of the invention;

FIG. 2 is a diagrammatic view of the preferred embodiment as employed for forming one form of truss;

FIG. 3 is a diagrammatic view of the preferred embodiment as employed for forming another type truss;

FIG. 4 is a perspective view illustrating an individual one of the plural nail-press means in a closed position as employed in the preferred embodiment;

FIG. 5 illustrates the top portion of the nail-press means of FIG. 4 in another position in which the parts are open for receiving timber elements to be joined by the clamping means;

FIG. 6 is a sectional view taken along lines 6-6 of FIG. 4;

FIG. 7 is a sectional view similar to FIG. 6 but illustrating the parts'in the position of operation at the completion of a work stroke with the nail-plates embedded in the timber members;

FIG. 8 is a sectional view taken along lines 8-8 of FIG. 6;

FIG. 9 is a sectional view taken along lines 9-9 of FIG. 1;

FIG. 10 is a sectional view taken along lines 10-10 of FIG.

FIG. 11 is a sectional view taken along lines 11-11 of FIG. 10;

FIG. 12 is a sectional view taken along lines 12-12 of FIG. 10;

FIG. 13 is a perspective view illustrating a modified form of nail-plate press means employed with the preferred embodiment;

FIG. 14 is a perspective view illustrating the clamping means of FIG. 13 in a different position of operation;

FIG. 15 is a top plan view of the clamping means of FIG. 14 with portions removed;

FIG. 16 is a sectional view taken along lines 16-16 of FIG. 14; I

FIG. 17 is a sectional view taken along lines 17-17 of FIG. 15;

FIG. 18 is a bisecting sectional view of another form of nailplate press means employed with the preferred embodiment; and

FIG. 19 is a sectional view taken along lines 19-19 of FIG. 18. DESCRIPTION OF THE PREFERRED EMBODIMENT Attention is initially invited to FIG. 1 of the drawings which comprises a plan view of the right hand portion of the preferred embodiment and includes a portion of the left-hand portion with it being understood that the left-hand portion that is omitted is symmetrical to the illustrated right-hand portion and for all intents and purposes identical thereto.

The preferred embodiment is mounted on a floor 18 or other flat horizontal surface and includes a plurality of fixed and movable rails with nail-plate press members being provided on the various rails for positioning to enable connection of timber members to form various forms of timber truss elements. The fixed rail members comprise a main central rail member in the form of an I-beam 20, a main base rail in the form of a floor mounted I-beam 22 extending in a transverse direction perpendicular to the main central rail 20 which has its forward end adjacent the middle of base rail 22. An intermediate transverse rail in the form of an I-Beam 24 and a third transverse rail in the form of an I-beam 26 are als affixed to the floor. The transversely extending

rails

22, 24 and 26 provide support for movable

interior flanking rails

28 and 30 respectively oriented on opposite sides of the central rail 20 as best shown in FIG. 2. Similarly, the main base rail 22 and the intermediate transverse rail 24 provides support for movable

exterior flanking rails

32 and 34 which a e also in the form of I-beams. All of the flanking rails are movable toward and away from the main central rail 20 in directions perpendicular to their axes as indicated by the arrows in FIG. 2. However, it should be understood that all of the flanking rails remain in parallel relationship with respect to the main central rail 20.

It should be noted that the transversely extending floor mounted rails 22, 24 and 26 are mounted on the floor 18 while the main central rail is supported in an elevated position by

support members

36 and 38 on each end thereof. The tops of the rails 24), 28, 30, 32 and 34 all lie in a common horizontal plane.

The manner in which the movable rails are supported will now be discussed with initial-reference being made to FIGS. 4 and 9 which illustrate the exterior rail 34. A vertically oriented transversely extending support'rail 36 is welded along one edge of the base flange 38 of the I-beam 22 comprising the main base rail. A carriage in the form of an angle member 40 with two vertical wheels 42 and four flanking wheels 44 which engage the support rail 36 is supported by rail 36 for movement therealong and is attached to the forward end of rail 34 by braces 45. The other end of movable exterior flanking rail 34 is provided with a pair of downwardly extending bracket plates 46 which support two upper rollers 48 and two lower rollers 50 respectively engageable with the top and bottom of the upper flange 52 of the intermediate transverse rail 34. Therefore, rail 34 is capable of movement along the

transverse rails

24 and 26 inwardly and outwardly with respect to the main central rail 20.

Similarly, the other movable exterior flanking rail 32 is supported on

rails

36 and 24 in an identical manner as rail 34.

Support for the movable rail 30 as shown in FIG. is quite similar to the support for the rail 34 in that a forward carriage comprising an angle 54 supporting vertical rollers 56 and flanking rollers 58 is supported for movement along the transversely extending support rail 36 in the same manner as the carriage connected to the front end of rail 34 as discussed previously. Moreover, rail 30 is connected to the angle 54 by means of brace arms 60 essentially identical to braces 45. Additionally, rail 30 is provided with roller-supporting brackets 62 analogous to brackets 46 of rail 34 which support upper rollers 64 and lower rollers 66 engageable with the upper flange 68 of the intermediate transverse rail 24 as best shown in FIG. 10. Rail 30 also has a pair of roller support brackets 70 adjacent its rearmost end which support rollers engageable with the upper flange 72 of rail 26 in the same manner as

rollers

64 and 66 engage flange 68.

Rails

20, 22, 28, 30, 32 and 34 all provide means for supporting nail-plate press-supporting carriages for movement along the lengths of the respective rails. The nail-press supporting carriages each comprise a main carriage frame in the form of a channel member 74 best illustrated in FIG. 4. Each carriage has four upper rollers 76 riding on the upper surface of the upper flange of the particular rail-with which the carriage is associated and also includes two lower rollers 78 mounted in the middle of each wall of the channel member and engageable with the lower surface of the flange of the rail. Consequently, each of the carriage members is easily reciprocated along the length of the particular rail with which it is associated.

A hollow pedestal column 80 extends upwardly from the main channel member 74 of each carriage for providing support for a nail-plate press means generally designated 82. The preferred embodiment for the nail-plate press illustrated in FIGS. 4, 5, 6, 7 and 8 comprises a main cylinder member 84 telescopically received within the interior of pedestal column 80 and which has a collar 86-welded to its outer periphery for engaging the upper end of the column so as to position the top of the cylinder 84 at a desired height.

Cylinder 84 is provided with an elongated access opening 88 upwardly above collar 86 and through which the lower end of a C-shaped frame member 90 formed of two spaced plates 91 extends. A piston 100 is mounted on the interior of cylinder 84 and has a rod 102 connected at its lower end by means of a pivot shaft 104 which extends through the plates 91 with the lower end of rod 102 extending downwardly between the lower end of the plates 91 as best illustrated in FIG. 6. Guide rollers 106 are retained for rotation on each outer end of shaft 104 by retaining clips or the like and are received between a vertical plate 108 and a cam plate 110 which are both fixed to the interior of cylinder 84. Each of the plates 91 is provided with an upper cam follower roller 114 mounted for rotation on stub shafts 116 extending outwardly from plates 91 as shown in FIG. 8.

The upper end of C-shaped frame 90 supports a movable platen 118 and a fixed platen 120 is supported on the upper end of cylinder 84. All of the fixed platens are in a common horizontal plane. A compression spring 122 on the interior of cylinder 84 engages an internal flange 124 on its lower end and engages the bottom of piston 100 on its upper end to consequently urge the piston upwardly at all times.

The center of gravity of C-shaped frame 90 and platen 118 is to the right of the axis of shaft 104 and the C-shaped frame and platen are consequently urged in a clockwise direction by virtue of the force of gravity. Therefore, when piston 100 is in its uppermost position illustrated in FIG. 6 in dashed lines, the C-shaped frame 90 assumes the dashed line position rotated clockwise from the solid line position of said figure. However, engagement of the cam follower roller 114 with the upper end of the'cam 110 limits the clockwise movement of frame 90 etc.

FIG. 5 of the drawings illustrates the open position of the nail-plate press which is assumed when the piston is at the top of the stroke under the urging of spring 122. In this position, a nail-plate 126 can be positioned on the fixed platen 120 and timber elements 128 can be subsequently positioned on the upper ends of the nails of the nail plate as will be obvious from inspection of FIG. 5. An upper nail-plate 130 is then placed on top of the positioned timber members 128 and pressurized air or other fluid is then introduced through a hose 132 to an inlet 134 in cylinder 84 above piston 100. Introduction of pressurized fluid moves piston 100 downwardly with cam follower roller 114 following the contour of cam 110 so that the C- shaped frame 90 and platens 118 are moved from the dashed line position of FIG. 6 into the solid line position of the same figure. Continued downward movement of piston 100 to the position illustrated in FIG. 7 results in vertical movement of the movable platen 118 against the upper nail-plate 130 so that both the upper and lower nail-plates are pressed into the timber members to provide a permanent connection therebetween as shown in FIG. 7. In actuality, all of the timber members for a particular desired truss are positioned on the various stationary platens of the various nail-plate press members 82 which are then simultaneously actuated to stamp nailplates into all of the members forming the truss.

It is necessary that each of the nail-plate press devices 82 be properly positioned in order to enable the fabrication of a desired truss member of a given span and height. For this reason, the subject invention provides means by which the nail-plate press devices are all accurately and automatically positioned by electric motor drive means. The means for accomplishing this result will now be discussed in detail.

Attention is initially invited to FIGS. 1 and 10 which illustrate a reversible drive motor 136 having a power output through a stepdown transmission 138 to a main output drive shaft 140 which is supported adjacent its forward end by a bearing 142 in the web of rail 22 as shown in FIG. 10. A first output sprocket 143 (FIGS. 10 & 11) is keyed on shaft 140 and has a chain 144 connecting it to a driven sprocket 146 which is keyed to a driven shaft 148. The rearmost end of driven shaft 148 is supported in a bearing 154 in the web of rail 24 and has an output drive pinion 156 mounted adjacent the bearing as shown in FIG. 10. Drive from shaft 148 to output drive sprocket 156 is enabled by means of a dog clutch 157 which can be connected or disconnected in accordance with whether or not it is desired to drive the sprocket. A rail shifting drive chain 158 is trained over sprocket 156 for a purpose to be discussed hereinafter.

The forward end of driven shaft 148 is supported by a support bracket 160 (FIG. 10) having a rotary bearing in which the shaft is received with a second output drive sprocket 162 being connected to the forwardmost end of shaft 148. A railshifting'drive chain 164 is trained over sprocket 162 and over an idler sprocket 166 attached to a floor-mounted bracket 168 (FIG. 1) with the ends of the chain being connected to lugs 170 extending downwardly from the lowermost flange of rail 34 on each side thereof as shown in FIG. 11. Consequently,

drive from output sprocket 162 serves to provide a laterally shifting force to the forward end of rail 34. Similarly, chain 158 is connected over an idler sprocket on a second floormounted bracket 172 adjacent the right end of rail 24 as shown in FIG. 1. The ends of chain 158 are connected to lugs 174 extending downwardly from each side of the bottom flange of rail 34. Therefore, it will be seen that drive from shaft 148 is provided through

sprockets

156 and 162 to

chains

164 and 158 for providing shifting movement of a rail 34 inwardly and outwardly with respect to the main central rail 20. It should be noted that the chain 158 extends upwardly through an opening in the upper flange of rail 24 so that the upper flight of the chain rests along the top of flange 68 of rail 24, while the lower flight is mounted between the two flanges of the rail.

A second driven shaft 176 is driven from shaft 148 by means of a connecting chain 178 extending about sprockets keyed to

shafts

148 and 176. The forward end of shaft 176 is supported in bearing bracket assembly 160 (FIG. and has an output drive sprocket 180 connected to the forward end of the shaft by means of a dog clutch. A chain 182 is trained over sprocket 180 and about an idler sprocket mounted on bracket 168 with the free ends of the chain being connected to a pair of lugs 184 extending downwardly from the bottom flange of rail 30. Similarly, the rearmost end of shaft 176 is provided with a sprocket 136 connectable to the shaft by a dog clutch and having a chain 188 extending therefrom. Chain 188 is looped over an idler sprocket 190 mounted on a bracket adjacent the right end of rail 26 with the ends of chain 188 being connected to lugs 192 extending downwardly from the lower flange of rail 30. Consequently, driving rotation of shaft 176 serves to shift rail 30 either inwardly or outwardly with respect to the central rail 20.

The forward end of the main drive shaft 140 has three output drive sprockets connected thereto by means of dog clutches for providing shifting movement of the three nailplate press devices 82 mounted on the right-hand portion of the main base rail 22 as viewed in FIG. 1. The output sprockets are all mounted in a cutout portion 198 of rail 22 as shown in FIG. 12 and comprise a first press shifting drive sprocket 200, a second press shifting drive sprocket 202 and a third press shifting drive sprocket 204. Chains extend from all of the sprockets along the upper surface of the upper flange of rail 22 and are looped over three idler sprockets mounted on a support bracket 206 on the rightmost end of rail 22 as viewed in FIG. 1. These chains comprise a chain 208 connected to sprocket 200 and having its free ends connected to the nailplate press designated 82' in FIG. 1. A chain 210 is connected to the intermediate nail-plate press 82" and also to sprocket 202 and a chain 212 is connected to sprocket 204 and the rightmost nail-plate press 82" It should be noted that it is necessary that the distances of the

press members

82, 82" and 82 from the main central rail 20 normally remain in a fixed ratio (i.e. the distance of press 82 should be a the distance of press 82". Therefore, shifting movement of press 82' etc. requires that the outermost press move three times the distance moved by the innermost press. This movement is accomplished by virtue of the fact that drive sprocket 200 is substantially smaller than drive sprocket 204. Consequently, each revolution of shaft 140 serves to drive press 82" three times the distance that press 82 is moved. Sprocket 202 is similarly proportioned to provide the desired movement of press 82".

In like manner, it is normally desirable that the ratio of the distances between the

rails

30 and 34 from the main central rail 20 remain constant. Therefore, it is normally desirable that rail 30 be shifted only one half the distance that rail 34 is shifted. If it should be desired to maintain a different ratio between the spacing of

rails

30 and 34, the sizes of the

sprockets

162 and 180 could be varied accordingly.

The foregoing discussion has been directed to the shifting movement of the elements in the right-hand portion of FIG. 1 of the drawings. However, it should be understood that movement of the elements to the left of main rail 20 is accomplished in exactly the same manner with a shaft 176 corresponding to shaft 176 and shaft 148' corresponding to shaft 148 and shaft corresponding to shaft 140. Drive to the elements to the left of main rail 20 is provided from an output drive sprocket 214 keyed to the main drive shaft 140 and having a chain 216 extending therefrom over an idler sprocket 218 attached to a floor-mounted bracket. The outer periphery of chain 216 engages a main input drive sprocket 220 keyed to the shaft 140' (FIG. 11). The purpose of having the outer periphery of chain 216 engage the sprocket 220 is for providing rotation of shaft 140 in a direction opposite the direction of rotation of shaft 140 in order that the elements driven from shaft 140' will be shifted in a direction opposite the direction of movement of elements driven from shaft 140. For example, if it is desired to move the

rails

28 and 30 outwardly, they must obviously be driven in opposite directions as evidenced from inspection of FIG. 2. A drive chain 144' analogous to chain 144 drives shaft 148' and a chain 178 extending from shaft 148 serves to drive shaft 176'. The drive connections to

rails

28 and 32 is identical to the drive chain connections to

rails

30 and 34.

In like manner, shaft 140' is connected through chains extending along the upper surface of a leftmost portion of rail 22 for shifting the press members 82 mounted thereon. The means for shifting the press elements is identical to the means employed for shifting elements 82', 82" and 82" as previously discussed.

The preceding discussion has been directed to the means for enabling shifting movement of the various rails at their associated nail-plate press means 82 inwardly and outwardly with respect to the central rail 20. However, it is also necessary that the press members 82 mounted on

rails

20, 32, 28, 30 and 34 must be accurately spaced with respect to the base rail 22. In other words, it is necessary that these press members he moved inwardly and outwardly with respect to the base rail in order to enable construction of truss members having various heights such as the two truss members illustrated in FIGS. 2 and 3. The manner in which this movement is accomplished will now be discussed in detail.

A variable speed electric motor 230 drives a splined shaft 232 by means of a drive chain 234 extending from the output of a stepdown transmission 236 to a sprocket 238 keyed to shaft 232. The manner in which splined shaft 232 shifts the various press members is identical for

rails

20, 28, 30, 32 and 34 and will be explained with reference to rail 34 as shown in FIG. 4. A bracket 239 attached to the forward end of rail 34 engages a sprocket 240 mounted for rotation on shaft 32. Sprocket 240 is driven by means of a dog clutch 242 normally urged into engagement with sprocket 240 by means of a spring or clamp member 244. Dog clutch 242 has a lug received within the slot of splined shaft 232 so as to be continuously driven thereby. However, dog clutch 242 can be disconnected from the sprocket 240 if desired. A chain 246 is connected to sprocket 240 and extends along the length of rail 34 over a rearwardly mounted idler sprocket 248 (FIG. 9). Sprocket 240 is freely rotatable on splined shaft 232 and is driven by means of engagement with dog clutch 242. However, sprocket 240 is shiftable along the length of shaft 232 upon lateral movement of rail 34in an obvious manner. Similarly, dog clutch 242 is also shiftable along the length of splined shaft 232.

Chain 246 is connected to lugs on the interior of the channel members 74 of nail-plate means 82 associated with the rail 34 so that rotation of sprocket 240 serves to move the nailplate press member along the length of rail 34 in an obvious manner. Drive sprockets and chains are similarly associated with

rails

30, 20, 28 and 32 in order for providing shifting movement of the various nail-plate press members associated with these rails. However, it should be noted that the size of the sprockets associated with

rails

28 and 30 will differ from the size of the sprockets associated with

rails

32 and 34 since the distances with which the press members associated with these respective rails must be shifted will vary in a manner analogous to the differences in distance that the

rails

30 and 34 must be shifted as was discussed previously. Shifting movement of the nail-plate press members mounted on central rail is always greater than the shifting movement of the other nail press assemblies mounted on the other rails and the sprocket for shifting the press assembly on rail 20 is consequently larger than any of the other sprockets.

Therefore, it will be seen that drive means provided by the instant invention provides automatic means for shifting the various nail-plate press devices laterally with respect to shaft 20 and for also varying the distance of those nail-plate press assemblies on

rails

20, 30 etc. from the base rail 22 in an automatic manner. Therefore, there is no necessity for manually shifting the nail-plate press devices for most truss constructions to be fabricated. However, the shifting drive to various nail press assemblies 82 can be disconnected through disconnecting various dog clutches when special design truss members are being fabricated.

FIGS. 18 and 19 illustrates a modified form of nail-plate press operable by an electric motor means instead of pneumatic means in a manner of the previously discussed press. The modified device employs a cylinder 84 that is essentially identical to the cylinder employed in the hydraulic press; however, a threaded rod 250 having threads 252 along its lower end in threaded engagement with the interior of a thrust nut 254 is substituted for the piston rod assembly of the hydraulic system. Nut 254 is rotated by an electric motor 256 which drives a worm 258 engageable with nut 254 so as to move rod 250 axially in an obvious manner. The upper end of rod 250 is received within a guide plate 260 on the interior of the cylinder 84 and reciprocation of the rod 250 serves to move the frame 90 in a manner identical to the movement of the frame of the hydraulic device. In fact, the only difference between the device of FIGS. 18 and 19 and the previously discussed hydraulic device is the employment of the electric motor for reciprocating the rod 250 rather than the usage of a hydraulic piston and cylinder. The devices are identical to each other in all other respects.

FIGS. 13-17 illustrate an attachment which can be provided on either the motor driven or hydraulic nail press devices for providing support for a large number of timber elements which are to be connected by a particular press assembly. This attachment comprises a U-shaped frame 270 which has a circular collar 272 encircling the upper end ofcylinder 84 and which is biased upwardly against the lower edge of the stationary platen 120 by a compression spring 274. The compression spring engages an external abutment collar 276 fixed to the exterior of cylinder 84 and consequently continuously biases the U-shaped frame 270 upwardly. The timber elements rest on the U-shaped frame 270 when it is in its uppermost position so that the lower nail plate 126 does not constitute the support for the timber elements prior to actuation of the press. In fact, the lower nail plate 126 does not provide any support for the timber elements. The advantage of this con= struction is that a large number of timber elements can be joined if desired in the support area provided by the reciprocable U-shaped frame 270 which is substantially larger than that of the nail plates. Therefore, this modification is of particular use on those press members in which alarge number of timber elements are to be joined. It is necessary that the U-shaped frame 270 be prevented from making any rotary motion during the impression of the nail plates in the timber elements which results in downwardly movement of frame 270. Therefore, steel spheres 280 mounted in the circular collar 272 and received with vertical grooves on the exterior of cylinder 84 prevent such rotation in a manner made obvious by inspection of FIG. 16, for example.

The versatility of the subject invention will be better appreciated upon inspection and comparison of FIGS. 2 and 3 of the drawings which illustrate the device in use for forming two different types of truss members. It will be obvious that practically all form of truss can be fabricated with the subject invention with a minimum of delay during changeover from one truss design to another. Additionally, the subject invention canbe controlled automatically by well-known machine tool control systems for providing an automatic changeover of the nail-plate press positions when it is desired to manufacture a different type truss. Since all of the drive sprockets 162, etc. are connected through releasable dog clutches to the shafts on which they are mounted, these sprockets can be disconnected from driving relationship to their support shafts to permit manual positioning of the various rails and press assemblies.

Iclaim:

1. An adjustable fabrication enabling means for fabricating wooden truss members formed of a plurality of timber elements joined together at juncture points bynail-plate connector means impressed into the timber members, saidassembly comprising a plurality of elongated movable nail-plate press supporting members, a plurality of nonmovable nail-plate press-supporting members, nail-plate press means adjustably mounted on said elongated movable nail-plate press supporting members for movement along the length of said elongated nail-plate press supporting members, other nail-plate press means mounted on said nonmovable nail-plate press-supporting members and motor means drivingly connected to adjustment means for simultaneously adjusting the position of said elongated movable nail-plate press-supporting members with I respect to each other and for simultaneously adjusting the position of each of said nail-plate press means mounted on said elongated movable nail-plate press-supporting members along the length of said elongated movable nail-plate supporting members by an amount in fixed ratio with respect to all other nail-plate press means on said movable nail-plate presssupporting members so that said nail-plate press members are completely adjusted automatically to enable a changeover for fabrication of different size truss members.

2. The invention of claim 1 wherein said nonmovable nailplate press supporting members comprise a main central rail means and a main base rail means oriented perpendicularly with respect to each other with one end of said main central rail means being adjacent the middle of said base rail means.

3. The invention of claim 2 wherein said elongated movable nail-plate press supporting members comprises movable flanking rails on each side of and in parallel relation to said main central rail means.

4. The invention of claim 3 wherein said flanking rails are mounted for movement perpendicular to their axes.

5. The invention of claim 4 wherein said flanking rails comprise first and second movable interior flanking rails respectively oriented on opposite sides of said main central rail means and first and second movable exterior flanking rails oriented outwardly of said interior flanking rails on opposite sides of said main central rail means.

6. The invention of claim 5 wherein said motor driven adjustment means includes power transmission means for moving said interior flanking rails simultaneously in opposite directions.

7. The invention of claim 6 wherein said motor driven adjustment means additionally includes transmission means for driving said exterior flanking rails in opposite directions simultaneously.

8. The invention of claim 7 wherein each of said nail-plate press means is mounted on a carriage member movable along the length of the respective rail with which the respective nailplate press means is associated.

9. The invention of claim 8 wherein said nail-plate press means includes a vertical cylinder, a power driven rod mova ble within said cylinder, a pivotable frame member connected to said power driven rod, a fixed platen supported by said cylinder, a movable platen attached to said pivotable frame member and cam means for pivoting said frame means from an open position in which said fixed platen is freely accessible to a closed position in which said movable platen is positioned over the fixed platen as said movable power driven rod moves from an upper position to a lower position to consequently provide nailnplate impressing force for impressing nail-plate means into timber members supported'on said fixed platen.

10. The invention of claim 9 wherein said pivotable frame member is C-shaped and extends through an opening into the interior of said cylinder with cam follower means attached to the C-shaped frame for engagement with said cam means and pivotable connection means for connecting said power-driven rod to said C-shaped frame.

1 l. The invention of claim additionally including hydraulic piston means connected to said power-driven rod for vertically reciprocating said power-driven rod.

12. The invention of claim 10 additionally including electric motor means driving a rotary thrust nut, threads on one end of said power driven rod threadably received within said rotary thrust nut so that rotation of said rotary thrust nut reciprocates said rod.

13. The invention of claim 9 additionally including a U- shaped frame extending about the periphery of said fixed platen and urged upwardly above the upper surface of said fixed platen for supporting timber members prior to actuation of said press means and spring means connected between said U-Shaped frame and said cylinder for biassing said U-shaped frame upwardly.

14. The invention of claim 10 wherein said cam follower means comprises first and second rollers on each side of said C-shaped frame engageable with said cam means which comprises a vertical plate and a spaced cam plate on each side of said C-shaped frame between which said rollers are received.

15. The invention of claim 14 additionally including hydraulic piston means connected to said power-driven rod for vertically reciprocating said power-driven rod.

16. The invention of claim 14 additionally including electric motor means driving a rotary thrust nut, threads on one end of said power-driven rod threadably received within said rotary thrust nut so that rotation of said rotary thrust nut reciprocates said rod.

17. The invention of claim 3 wherein said nail-plate press means includes a vertical cylinder, a power driven rod movable within said cylinder, a pivotable frame member connected to said power driven rod, a fixed platen supported by said cylinder, a movable platen attached to said pivotable frame member and cam means for pivoting said frame means from an open position in which said fixed platen is freely accessible to a closed position in which said movable platen is positioned over the fixed platen as said movable power-driven rod moves from an upper position to a lower position to consequently provide nail-plate impressing force for impressing nail-plate means into timber members supported on said fixed platen.

18. The invention of claim 17 wherein said pivotable frame member is C-shaped and extends through an opening into the interior of said cylinder with cam follower means attached to the C-shaped frame for engagement with said cam means and pivotable connection means for connecting said power-driven rod to said C-shaped frame.

' 19. The invention of claim 18 additionally including hydraulic piston means connected to said power-driven rod for vertically reciprocating said power-driven rod.

20. The invention of claim 17 additionally including electric motor means driving a rotary thrust nut, threads on one end of said power-driven rod threadably received within said rotary thrust nut so that rotation of said rotary thrust nut reciprocates said rod.

21. The invention of claim 2 wherein said adjustment means additionally includes power-transmitting means connected to a movable nail-plate press mounted on said main central rail means for adjusting the position of said nail-plate press on said main central rail means by an amount in fixed ratio to the amount of adjustment of said nail-plate press means mounted for movement along the length of said elongated movable nailplate press-supporting members.

22. The invention of claim 21 wherein said elongated movable nail-plate press supporting members comprise movable flanking rails on each side of and in parallel relation to said main central rail means.

23. The invention of claim 22 wherein the flanking rails comprise first and second movable interior flanking rails respectively oriented on opposite sides of said main central rail means for movement perpendicular to their axes and first and second movable exterior flanking rails oriented outwardly of said interior flanking rails on opposite sides of said main central rail means for movement perpendicular to their axes.

24. The invention of claim 23 wherein said motor driven adjustment means includes power transmission means for moving said interior flanking rails simultaneously in opposite directions.

25. The invention of claim 24 wherein said motor driven adjustment means additionally includes transmission means for driving said exterior flanking rails in opposite directions simultaneously.

Claims

1. An adjustable fabrication enabling means for fabricating wooden truss members formed of a plurality of timber elements joined together at juncture points by nail-plate connector means impressed into the timber members, said assembly comprising a plurality of elongated movable nail-plate press supporting members, a plurality of nonmovable nail-plate press-supportIng members, nail-plate press means adjustably mounted on said elongated movable nail-plate press supporting members for movement along the length of said elongated nail-plate press supporting members, other nail-plate press means mounted on said nonmovable nail-plate press-supporting members and motor means drivingly connected to adjustment means for simultaneously adjusting the position of said elongated movable nail-plate press-supporting members with respect to each other and for simultaneously adjusting the position of each of said nail-plate press means mounted on said elongated movable nail-plate presssupporting members along the length of said elongated movable nail-plate supporting members by an amount in fixed ratio with respect to all other nail-plate press means on said movable nailplate press-supporting members so that said nail-plate press members are completely adjusted automatically to enable a changeover for fabrication of different size truss members.

2. The invention of claim 1 wherein said nonmovable nail-plate press supporting members comprise a main central rail means and a main base rail means oriented perpendicularly with respect to each other with one end of said main central rail means being adjacent the middle of said base rail means.

8. The invention of claim 7 wherein each of said nail-plate press means is mounted on a carriage member movable along the length of the respective rail with which the respective nail-plate press means is associated.

9. The invention of claim 8 wherein said nail-plate press means includes a vertical cylinder, a power driven rod movable within said cylinder, a pivotable frame member connected to said power driven rod, a fixed platen supported by said cylinder, a movable platen attached to said pivotable frame member and cam means for pivoting said frame means from an open position in which said fixed platen is freely accessible to a closed position in which said movable platen is positioned over the fixed platen as said movable power driven rod moves from an upper position to a lower position to consequently provide nail-plate impressing force for impressing nail-plate means into timber members supported on said fixed platen.

11. The invention of claim 10 additionally including hydraulic piston means connected to said power-driven rod for vertically reciprocating said power-driven rod.

12. The invention of claim 10 additionally including electric motor means driving a rotary thrust nut, threads on one end of said power driven rod threadably received within said rotary thrust nut so that rotation of said rotary thrust nut reciprocates said rod. 13. The invention of claim 9 additionally including a U-shaped frame extending about the periphery of said fixed platen and urged upwardly above the upper surface of said fixed platen for supporting timber members prior to actuation of said press means and spring means connected between said U-Shaped frame and said cylinder for biassing said U-shaped frame upwardly.

19. The invention of claim 18 additionally including hydraulic piston means connected to said power-driven rod for vertically reciprocating said power-driven rod.

21. The invention of claim 2 wherein said adjustment means additionally includes power-transmitting means connected to a movable nail-plate press mounted on said main central rail means for adjusting the position of said nail-plate press on said main central rail means by an amount in fixed ratio to the amount of adjustment of said nail-plate press means mounted for movement along the length of said elongated movable nail-plate press-supporting members.