US3824919A

US3824919A - Method of and apparatus for fabricating wood structures

Info

Publication number: US3824919A
Application number: US00305518A
Authority: US
Inventors: W Moehlenpah
Original assignee: Moehlenpah Walter George
Current assignee: Gang Nail Systems Inc; Mitek Holdings Inc
Priority date: 1972-11-10
Filing date: 1972-11-10
Publication date: 1974-07-23
Anticipated expiration: 1991-07-23
Also published as: GB1403335A; FR2206159B1; JPS5430155B2; CA1011933A; DE2356939A1; JPS5024865A; FR2206159A1

Abstract

A method and apparatus for fabricating wood structures utilizing a C-shaped press having an upper platen and a lower platen which are relatively movable toward and away from one another for driving nailing plates into two or more wood members from above and below, in which the wood members are held in position for being nailed together on a plurality of stands arranged on lines bounding the structure. Each such stand includes means for supporting the wood members and has a holder plate adapted to hold a nailing plate for being driven upwardly into the wood member from below by the lower platen of the press. The supporting means and the holder plate are so mounted on the stands as to enable lateral entry of the lower platen of the press from either side of the stand to an operating position below the holder plate. The press is mounted for generally lateral movement with respect to the press substantially sidewise into and away from an operating position at each such stand. Means are provided for preventing operation of the press unless it is in an operating position at a stand.

Description

United StatesjPatent n91- Moehlenpah v v [111 3,824,919 51 July 23,1974

[ METHOD OF AND APPARATUSFOR FABRICATING WOOD STRUCTURES [76] Inventor: Walter G. Moehlenpah, 9906 Old Warson Rd., Ladue, Mo. 63124 [22] Filed: Nov. 10, 1972 [21] Appl. No.: 305,518

[52] US. Cl 100/35, lOO/DlG. l3, 100/53,

7 100/231, 100/269 R, 227/152 [51] Int. Cl B30b 13/00 [58] .Field of Search 100/35, 53, 231, 269 R,

l00/DIG. 13; 227/152; 335/205 [56] References Cited UNITED STATES PATENTS 3,068,484 12/1962 Moehlenpah et al. l00/DlG. 13 3,069,684 12/1962 Moehlenpah et al. 100/DlGhl3 3,487,430 12/1969 Schmitt loo/DIG. 13

Primary Examiner-Billy J. Wilhite Attorney, Agent, or Firm-Koenig, Senniger, Powers and Leavitt [57] ABSTRACT A method and apparatus for fabricating wood structures utilizing a C-shaped press having an upper platen and a lower platen which are relatively movable toward and away from one another for driving nailing plates into two or more wood members from above and below, in which the wood members are held in position for being nailed together on a plurality of stands arranged on lines bounding the structure. Each such stand includes means for supporting the wood members and has a holder plate adapted to hold a nailing plate for being driven upwardly into the wood member from below by the lower platen of the press. The supporting means and the holder plate are so mounted on the stands as to enable lateral entry of the lower platen of the press from either side of the stand to an operating position below the holder plate. The

. press is mounted for generally lateral movement with respect to the press substantially sidewise into and away from an operating position at each such stand. Means are provided for preventing operation of the press unless it is in an operating position at a stand.

29 Claims, 11 Drawing Figures PAIENTEDJULZBIQH SHEEY 2 BF 6 innnnnnnn PATENIEDJULZIHQH sum 3 or 6 FIG.5

FIG.6

PATENTED HLN 3.824.919

SHEET 6 OF 5 PEG-.IO

, 1 METHOD OF AND APPARATUS FOR FABRICATING WOOD STRUCTURES BACKGROUND OF THE INVENTION This invention relates to the fabrication of wood structures, and more particularly to a method of and apparatus for fabricating wood structures utilizing a C- shaped press to drive nailing plates into two or more wood members.

U.S. Pat. Nos. 3,068,484 and 3,069,684 show prior art truss fabricating apparatus utilizing a C-shaped press having an upper platen and a lower platen for driving nailing plates into two or more wood members from above and below having a plurality of pedestals (or stands) for supporting the wood members in position. Each of the pedestals includes a holder or locator 2 upward or downward force thereto. The press is then opened and moved generally laterally with respect to the press substantially sidewise out of the stand and over to the next successive stand. The press is maintained adjacent to the wood members supported by these stands as it is moved and it enters the next successive stand substantially from the side thereof to bring it to its operating position at the next successive stand. The press is again operated to drive the nailing plates into the wood members, and the latter two steps are repeated as the press is moved between successive stands thereby to nail additional wood joints.

Apparatus of this invention generally comprises a series of stands for holding the wood members which are plate for holding a lower nailing plate in position below the wood members for being driven upwardly by the lower platen of the press which is adapted to be positioned in a nailing plate driving position within the pedestal. Other prior art fabricating apparatus is shown in U.S. Pat. No. 3,487,430. Wood members have also been supported in a cantilevered position forforming joints with nailing plates. However, in all such prior known wood fabrication systems the press was not moved laterally (with respect to the press) substantially sidewise out of one stand and over to the next stand for sidewise entry thereinto where the press would operate to drive nailing plates into the wood members without applying any substantial net upward or downward force, and the presswas not prevented from operating if the press was in other than an operating position at one of the stands.

SUMMARY OF THE INVENTION Among the several objects of this invention may be noted the provision of methods of and apparatus for fabricating wood structures which minimize the time and effort required in forming a number of joints between wood members such as neededin fabricating roof and floor trusses or the like; the provision of such to be secured together at their joints by nailing plates to form a wood structure. The stands are arranged at joints, and each such stand has a support and means cantilevered relative to the support for holding wood members with clearance therebelow. A press is provided having an upper platen and a lower platen which are relatively movable toward and away from one another for driving nailing plates into thewood members from above and below. Also provided is means mounting the press for generally lateral movement of the press substantially sidewise into and away from an operating position at each of the stands for driving nailing apparatus in which nailing plates are driven into the wood members without applying any substantial net upward or downward .force thereto whereby light, strong joints are formed between the wood members; the provision of such apparatus which utilizes a single press movable from stand-to-stand substantially along a line of stands to form said joints and which facilitates positioning of the press in an operating position at each of the stands; and the provision of such methods and apparatus which permit more rapid and efficient production of such relatively large wood structures.

In general, the method of this invention utilizes a C- shaped press having an upper platen and a lower platen which are relatively movable toward and away from one another for driving nailing plates into two or more wood members from above and below, and comprises supporting the wood members, which are to be nailed together at joints to form a wood structure, on a plural ity of stands arranged at the joints, with clearance below the wood members for movement of the lower platen of the press underneath the wood members. The press is brought into an operating position at one of the stands with its lower platen below the wood members. The press is then operated to drive the nailing plate into the wood members without applying any substantial net plates into the wood members held by that stand. Preferably means are provided for preventing operation of the press unless it is at an operating position at one of said stands.

Other objects and features will be in part apparent and in part pointed out hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view showing apparatus of this invention set up to fabricate a W-type truss;

FIG. 2 is a front elevation of the apparatus, showing a hydraulic press assembly;

FIG. 3 is an enlarged plan view of a first embodiment of one of the stands with parts broken away;

FIG. 4 is a front elevation of the stand of FIG. 3 with the lower portion of the hydraulic press (shown in phantom) in its operating position;

FIG. 5 is an enlarged plan view of a second embodiment of one of the stands with parts broken away;

FIG. 6 is a front elevation of the stand of FIG. 5 with parts broken away;

FIG. 7 is a side elevation of the stand of FIG. 5 showing the press in its operating position, with respect to the stand, and showing means for facilitating positioning of the press in its operating position;

FIG. 8 is a hydraulic schematic;

FIG. 9 is anelectrical schematic;

FIG. 10 is a semi-diagrammatic view depicting movement of the press (shown in phantom) into and out of its operating position at a Stand of this invention; and

FIG. 1 l is a semi-diagrammatic view depicting movement as in the prior art of a press into and out of its operating position at a prior art stand.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, FIGS. 1 and 2 show apparatus of this invention, generally indicated at 1, for fabricating wood structures, e.g., wood trusses, such as indicated'at T. The apparatus comprises a series of stands generally indicated at 3 for holding precut wood members M which are to be secured together'at their joints by upper and lower nailing plates UN and LN, respectively. The stands are arranged at the joints on straight lines bounding the wood structure to be fabricated and each stand has a support or base generally indicated at 5 and means indicated at 7 for holding the wood members cantilevered relative to the support. The apparatus further comprises a C-shaped hydraulic press generally indicated at 9 which has an upper platen 1 1 and a lower platen 13 which are relatively movable toward and away from one another for driving nailing plates into the wood members from above and below. Means generally indicated at 15 carries the press 9 for moving it into an operating position (the position of the lower platen is indicated at A in FIG. for driving the nailing plates into the wood members M at one of the stands, for movement in a generally lateral direction with respect to the press(as shown by the arrows in FIG. 10) substantially sidewise out of its operating position at the one said stand and over the next successive stand and into its operating position at this next successive stand, with the press being maintained substantially adjacent wood members M supported by these stands as it is moved. Means also carries the press in such manner so as to drive the nailing plates into the wood members from above and below without exerting any substantial net upward or downward force (aswill be hereinafter described) on the wood members by the platens.

As shown in FIG. 1, the apparatus 1 is set up to fabricate a W-truss, but it will be understood that the method and apparatus of this invention may be adapted to fabricate a wide variety of triangular or flat trusses. More particularly, the apparatus is shown as comprising a pluralityofthe stands 3 movable to different posi- 4 toward the interior of truss T, and extends up above the top 37. The hollow wall 39' is formed by an outer vertical wall 41 secured as by welding to the upper portions of the side channels 33. This outer vertical wall carries inwardly facing flanges 43 at each side and has an inner vertical wall 45 secured thereto.

Referring now to FIG. 7, the wood member holding means 7 includes two cantilever arms, each designated 47, in side-by-side spaced relation and extending forwardly over the base top 37 from the outer sides of hollow wall 39. The top surfaces of the cantilever arms 47 are positioned above the top of wall 39 and are adapted to support the wood members M in position to be secured together by upper nailing plates UN and lower nailing plates LN. The cantilever arms are located above the base top'37 a sufficient distance to permit the entry of the lower platen 13 of the press 9 from one lateral side or the other of the stand belowthe cantilever arms 47 to its operating position (as shown in FIGS. 4, 7 and 10) in a vertical plane generally midway between the cantilever arms. The top surfaces of the cantilever arms are spaced from the top surface of the tions to correspond to the joints at the intersections of two or more wood members M in their assembled position. The lower chord stands, indicated at 17, and the peak stand '19, are mounted on a lower chord track 21 and a center track 23, respectively. The upper chord stands 25are slidably mounted on the floor and are adapted (when moved to their desired positions) to be rigidly clamped at those positions by locking

extensible telescoping links

27 and 29. The track mounted stands each have a screw clamp 31 for rigidly clamping them in their desired positions on their respective tracks. The stands 17, 19 and 25 generally correspond to the

pedestals

9, 13, 17, 19 and 21 shown in U.S. Pat. No. 3,068,484, tracks 21 and 23 herein correspond to tracks 11 and 15, and

telescoping links

27 and 29 correspond to

links

23 and 25, respectively, in the abovementioned patent. It will be understood that the stands 3 of this invention may be mounted on the track arrangement shown in U.S. Pat. No. 3,693,542 in which event no telescoping links are used.

As shown in FIGS. 3-7, each stand 3 includes a support or base 5 comprising a pair of inwardly facing channels, each designated 33, which constitute stand side members. The channels 33 are joined at their bottoms by angle members 35 and have a horizontal top 37 extending between theupper portions of the channels constituting the top of the base. A vertical hollow wall 39 is secured to the back of the base, i.e., the side lower platen 13 a distance sufficient to accommodate the lower nailing plate LN arranged with its teeth pointing up for being driven into the wood members from below. As shown in FIG. 4, the cantilever arms 47 are laterally spaced from one another a distance greater than the width of the lower platen 13 of the press for entry of the lower platen between the arms when the press is in its operating position and the lower platen is moved upwardly to drive the lower nailing plate LN into the wood members.

At the back ends of the cantileverd arms 47, a horizontal member 49 is secured to the upper portion of outer wall 41 with the top surface of member 49 at substantially the same level as the top surface of the cantilever arms. Each arm 47 is cantilever-supported by an angle member 51 secured to the outer wall 41 and extending outwardly therefrom, and member 49 is supported by an angle member 53 welded to the upper portion of the outer wall. The cantilever arms 47 and the horizontal member 49 correspond to the channelshaped guides 103 and 71, respectively, shown in the aforementioned U.S. Pat. No. 3,068,484, and are adapted to carry clamping and aligning means (not shown) similar to those indicated by

reference numberals

75, 77 and 105 in the last-said patentfor holding the wood members M.

Wood member holding means 7 further includes a holder or a locator plate 55 cantilevered outwardly from the support 5 constituting means at each stand for holding a lowernailing plate LN below the wood members M supported on the cantilever arms 47. The holder or locator plate 55 is positioned between the cantilever arms 47 and is carried by the support for upward and downward movement relative thereto for being driven upwardly by the lower platen 13 of the press 9 from a lower retracted position (as shown in FIG. 4) below the top surface of the cantilever arms 47 to drive the lower nailing plate LN positioned thereon into the wood members from below. The operating position (e.g., A in FIG. 10) of the press is more particularly defined as that position at each of the stands in which the press and its platens are substantially centered between the cantilever arms 47 and the platens are positioned vertically relative to the wood members M and fore and aft relative to wall 45 so as to be above and below the joint in the wood members with lower platen 13 below holder plate 55 when the latter is in its lowered retracted position and with the upper platen 11 above the joint in the wood members. Thus, with the press in its operating position, the press may be operated to drive the nailing plates into the wood members without damage to the stand. The operating position of i the press is also shown in FIGS. 4 and 7.

Locator plate 55 is cantilever-supported outwardly from the wall 45 by a pair of rods, each designated 57, secured to its lower face adjacent the back edge thereof. Means generally indicated at 58 is carried by the stand for guiding rods 57. More particularly, in one embodiment, as shown in FIGS. 3 and 4, this guide 1

guide rollers

64a, 64b of nylon or the like and which are vertically movable within hollow wall 39 such that the guide rollers and the hollow walltogether constitute guide means 58. In both of the abovedescribed embodiments, the upper edge of wall 45 constitutes a stop and prevents the locator plate from moving substantially below its lowered retracted position, and the locator plate is gravity-biased to remain in its lowered retracted position. Additionally, the guide means 58 of both of the above-described embodiments accurately maintains the holder plate in a substantially horizontal position as the holder plate is moved from its lower retracted position to drive the lower nailing plate LN positioned thereon into the wood members M from below. Thus, the teeth of the lower nailing plate are maintained in substantially perpendicular relation to the lower surface of the wood members M so that they engage the lower surface of the wood members at substantially the same time thereby to facilitate forming tight, strong joints. Locator strips 65 are optionally provided on the top surface of the locator plate to accurately position the lowernailing plate LN relative to the respective wood members supported thereabove.

Referring now to FIG. 2, the hydraulic press 9 may correspond to the press indicated at 35 in US. Pat. No. 3,068,484, and it is herein-shown to be supported for universal movement by mounting means which comprises a yoke 66, a cable 67 attached to the yoke and to one end of a boom 69. The latter is counterbalanced by a hydraulic pump and electric motor assembly 71 at the other end of the boom. A pivotal hanger 73 suspends the boom from a carriage 75 which is movable along an overhead l-beam 77 suspended from the ceiling, or from other overhead structure. The hanger 73, the counterbalanced boom 69, and the movable carriage 75 permit horizontal movement of the press from stand to stand for nailing plate driving purposes and permit vertical movement during driving of the nailing plates into the wood members without exerting any substantial net upward or downward force on the wood members. A substantial net upward or downward force on the wood members is one which would move the wood members relative to each other to open the joints therebetween, or would force a wood member out of its clamps, or would deflect the cantilever arms 47. Such a substantial force may be applied to the wood members by one platen of the press exerting a greater force on thewood members than the other, or by supporting all or a significant part of the weight of the press on the wood members. Generally, such a substantial net upward or downward net force is one that does not exceed about 5 percent of the capacity of the press and preferably does not exceed about 500 lb. It will be understood that press 9 may also be carried by a movable gantry, and in instances where a significant upward or downward force on the wood members is not critical, the press may be mounted for movement in a horizontal plane but without being free to move vertically.

As shown in FIG. 7, the press 9 comprises a C-shaped frame 79 on which the lower platen 13 is fixed and carries the upper platen 11 which is movable via a hydraulic power cylinder 81. The hydraulic cylinder is interconnected to the hydraulic pump of assembly 71 by hydraulic fluids lines 83 and 84 (FIG. 8) for providing hydraulic fluid under pressure to move the upper platen toward and away from the lower platen. Pistol grip handles 85 are provided on opposite sides of frame 81 (only the left-hand handle 85 is shown in FIG. 7) so as to enable the press operator readily to control the movement and operation of the press. Push button electrical switch PB1 is mounted on one of the handles 85 and switch PB2 is positioned on the other for controlling movement of the carriage along I-beam 77. Push button electrical switches PB3 and PB4 are also respectively provided on handles for controlling operation of the platens of the press. Hydraulic and electrical circuits (FIGS. 8 and 9) including the abovementioned push button switches will be more fully explained hereinafter.

In accordance with this invention, means generally indicated at 87 (see FIG. 7) is provided for preventing operation of theplatens of press 9 to drive nailing plates into the wood members except when the press is in its operating position (see FIGS. 4 and 7) thus insuring that the press will not damage the stand by being operated when it is improperly positioned relatively to the holder and the stand, and further insuring that nailing plates LN and UN will be properly driven into the wood members from above and below to form a tight, strong joint. Moreover, by preventing operation of the press, means 87 facilitates positioning of the press in its operating position at each of the stands 5.

More particularly, means 87 includes a magnetic switch 89 (e.g., a magnetic reed switch such as manufactured by Cutler-Hammer) and a magnet 91 (a permanent magnet) together constituting proximity sensing means responsive to movement of press 9 into its operating position at each of the stands 5. Magnetic switch 89 is mounted on the nose of press frame 79 below lower platen 13 and is actuable in response to a magnetic field of a predetermined strength. The magnetic switch is connected in series with push buttons PB3 and PB4 to prevent operation of the press unless the magnetic switch is also actuated. Magnet 91 is mounted on inner wall 45 of the stand in the vertical central plane between arms 47 (see FIGS. 4 and 5) so that it is adjacent the magnetic switch when the press is in its operating position. Magnet 91 produces a magnetic field of sufficient strength (i.e., the effective field of the magnet) to actuate the switch when the switch 7 is within the effective field. Typically, this effective field extends from the magnet about 1% inches in all directions. Thus, unless the press is properly positioned at a stand in its operating position with its switch 89 in the effective field of magnet 91, operation of the 'press is prevented. It will be understood that means 87 may be constituted by components other than a magnet and magnetic switch. For example, photoelectric'or induction-type proximity switches carried by the press may also be used to signal when the press is in its operating position.

The hydraulic pump and electric motor assembly 71 heretofore described includes a conventional hydraulic pump 93 mounted in a tank or sump 95 on the right end of hanger beam 69 (as viewed in FIG. 2). An electric motor 97 is mounted on the sump for driving the pump. The motor is supplied with current from an electrical source(not shown) via line 99. Carriage 75 is driven along I-beam77 by a hydraulic carriage motor 101 supplied with hydraulic fluid under pressure frompump 93 via

lines

103 and 105, this arrangement being similar to the carriage drive shown in'FIGS. 13-15 of the'previously mentioned US. Pat. No. 3,068,484.

F IG'. 8 shows the hydraulic circuit for press 9 and carriage motor 101. Pump 93 is supplied with hydraulic fluid from sump 95 via a line 107. The pump via a line 109 directs hydraulic fluid under pressure to an inlet port Vla of a three-way valve V1. The spool of valve motor via line 105. Valves V7 and V8 together constitute means for regulating the speed of motor 101. Check valves V9 and V10 are included in

lines

103 and 105, respectively, and are connected in parallel to their respective metering valves V7 and V8 to permit low pressure fluid from the motor to drain to the sump without passing through the metering valves. These check valves each block the flow of pressurized fluid to the motor and thus force the liquid through their respective metering valve.

Referring now to FIG. 9 illustrating the electrical circuit, pump motor 97 is supplied with power from an electric power source via line 99 including lines L1, L2 and L3. The primary of a step-down transformer 113 is connected across lines L2 and L3 by lines 115 and 117. The secondary of the transformer supplies electrical power to lines 119 and 121. Switch P131 is connected across lines 119 and 121 in a line 123 including solenoid Z. Switch PB2 is connected across lines 119 and 121 in a line 125 including solenoid Y. Push buttons PB3 and PB4 and magnetic switch 89 are connected in series across lines 119 and 121 in a line 127 including a time delay relay TD1 which prevents operation of carriage motor 101 while the press is hydraulically actuated. This time delay relay includes contacts C1, C2, C3 and C4 with contact C1 included in a line 129, contacts C2 and C3 included in a line 131, and

. contact C4 included in line 121. Upon energization of V1 is controlled by solenoids Wand X.- This valve has I a pressure outlet'port Vlb connected to the upper end of hydraulic cylinder 81 via line 83 .for supplying hydraulic fluid-under pressure to the press for effecting movement of the platens toward one another, a second outlet port Vlc. connected to the lower end of the hydraulic cylinder via line 84 for supplying hydraulic fluid to the lower end of the hydraulic cylinder to effect movement of the platens away from one another after the joint in the woodmembers has been formed, and a third outlet port Vld connected to the inlet port V2a of a valve V2.via a line 111 for supplying hydraulic fluid to motor 101.

Pressure relief valves V3 and V4 are provided in line 109 to return hydraulic fluid to sump 95 in the event pressure in the hydraulic system exceeds a predetermined .value. More particularly, valve V3 is adjustable to control the pressure supplied to the press to thus vary the maximum force the platens may exert on the wood members, and valve V4 is a safety valve preset to limit the maximum pressure in. the system. An unloader valve V5 is included in line 83 operable in response to increase in pressure in line 84 to drain fluid from the hydraulic cylinder to the sump as the platens are moved apart from one another. A relief valve V6 is provided in line 84 to relieve pressure therein and thus limit the force applied to the hydraulic cylinder when the upper platen is fully retracted and to limit the pressure of the fluid supplied to motor 101.

Valve V2 is a three-way valve whose spool is controlled by solenoids Y and Z. In addition tov port V2a, valve V2 has an outlet port V2b connected to one side of carriage motor 101 via line 103, a second outlet port V2c connected to the other side of the motor by line 105, and a drain port V2d in communication with sump 95. Line 103 includes an adjustablemetering valve V7 for controlling the flow of hydraulic fluid to motor 101 via line 103, and a similar metering valve V8 is included in line 105 to control the flow of fluid to the relay TDl (which can only occur when the press is in its operating position at a stand Sand magnetic switch 89' is actuated and when both push buttons PB3 and PB4 are depressed), contacts Cl and C2 close, and contacts C3 and'C4 open. The closing of contact C1 energizes solenoid W and the opening of contact C4 prevents energization of solenoids Y and Z and thus prevents movement of carriage along beam 77. Energization of solenoid W shiftsthe spool of valve V1 from the position shown in FIG. 8 so that hydraulic fluid is supplied to the press via line 83 to effect movement of the platens toward one another for driving the nailing plates into the wood members. Releasing either of the push buttons PB3 or PB4, or moving the press from its operating position and thus opening magnetic switch 89, de-energizes relay TDl. This in turn instantly opens contact C1 and closes contact C3 thereby to respectively de-energize the solenoid W and'to energize solenoid X. This shifts the spool in valve V1 back to the position shown in FIG. 8 and permits hydraulic fluid to flow in lines 84 for niovingthe platens apart and in line 111 for supplying hydraulic fluid to valve V2. After a time delay to permit sufficient separation of the platens, contacts C2 of the delay relay open and contacts C4 close thereby to respectively de-energize solnenoid X and to complete line 121 so that upon actuation of push buttons FBI and PB2, motor 101 will operate to drive the carriage along I-beam 77 to move the press from stand to stand.

In operation, the stands 3 are arranged to correspond to the joints of the wood members M which are to be nailed together by nailing plates UN and LN to form the desired wood structure T. The lower nailing plates LN with their teeth pointing up are then placed on the holder or locator plates 55 of the several stands in proper position as determined by locator strips 65. The precut wood members M are then placed in position and supported on the cantilever arms 47 and clamped in position to be secured together by the above said clamping and aligning means. The upper nailing plates UN with their teeth pointing down are then manually placed over the joints of the various wood members as shown in FIG. 4. It will be noted that operation of the press is prevented by magnetic switch 89 unless the press is in its operating position at one of the stands, thereby facilitating rapid and efficient positioning the press in its working station.

In accordance with the method of this invention (as particularly illustrated in FIG. the hydraulic press 9 is moved to one of the stands 3, e.g., the stand at the end of one of the straight lines of stands that bound the wood structure T, and the lower platen 13 of the press is moved sidewise from a position laterally of the stand, as indicated at B, below arms 47 of the stand to its operating position A.

With the press in its operating position A, magnet 91 actuates magnetic switch 89 thereby permitting operation of the press when both push buttons PB3 and PB4 are depressed. The press is mounted for universal movement on boom 69 so that as hydraulic cylinder 81 is actuated, upper platen 11 is moved downwardly to contact the upper side of the upper nailing plate UN. Continued actuation of the hydraulic cylinder causes press frame 79 and lower platen 13 to move upwardly without exerting any substantial net upward or downward force on the wood members, which in turncauses the lower platen to engage the lower surface of holder 55 to drive it upwardly until the teeth of the lower nailing plate LN resting thereon contact the lower surface of the wood members. Further actuation of the hydraulic cylinder causes the platens to move toward one another driving the nailing plates into the wood members from above and below. The universal movement of the press permits the lower platen and the upper platen to be simultaneously in position to drive their respective nailing plates into the wood members without placing any substantial net upward or downward forces on the wood members, and to drive the nailing plates into the wood members with equalized forces on each nailing plate. This equalized application of forces on the wood members prevents any substantial net upward or downward force from being applied to the cantilever arm 47 which would cause the cantilever arms to bend and the wood members to move relative to one another thereby preventing proper securing by the nailing plates, and enables the efficient production of trusses having tight, strong joints.

The press 9 is then opened by moving the upper platen 11 away from the lower platen 13 by releasing push buttons PB3 and PB4 and thus reversely actuating the hydraulic cyliner 81. The holder 55 is gravitybiased to return to its lower retracted position as the lower platen moves downwardly relative to the wood members. By swinging the boom 69'about the pivotal hanger 73 and/or by moving the carriage 75 along the I-beam track 77, the press is moved sidewise out of the stand from its operating position A through a position such as indicated at C below arms 47 and then moved completely clear of the stand and along the line of stands adjacent the wood members M to the next successive stand to assume its operating position therein.

The press is then again operated to drive the respective nailing plates into the wood members. Due to the cantilever arms 47 permitting lateral or sidewise entry of the lower platen of the press into each stand, the press may be moved directly from stand-to-stand in one continuous movement without any significant in and out movement relative to the wood structure (i.e., it is maintained closely adjacent the wood members) as it is moved into and out of its sequence of operating positions at successive stands.

In contrast, movement of the press of typical prior art apparatus in the same general field as the apparatus of the present invention, for example, such prior art apparatus as is shown in my above mentioned U.S. Pat. No. 3,068,484, is illustrated in FIG. 11 (the reference characters in FIG. 11 corresponding to the reference characters in my above-mentioned patent). This prior art apparatus included stands 17, 19 (as illustrated in FIGS. 3, 4, 7 and 8 in the above-mentioned patent) having two

guides

67, 69 at the sides of the stand and a bar 71 at the rear thereof for supporting wood members T on the stand (these guides and bar corresponding to arms 47 and bar 49 of the present invention).

Guides

67 and 69 are supported by

stand side walls

41 and 43, respectively, so that the lower platen of press 35 may enter the stand only from the front thereof. More particularly, movement of the lower platen of press 35 of such prior art apparatus into its operating position, as indicated at D in FIG. 11, at successive stands or pedestals 17 or 19 required that the press be moved sidewise (as shown by the arrows in FIG. 11 herein) from a position E at the side and in front of the stand to an entry/exit position F directly in front of the stand. The operator then moved the press inwardly toward its operating position D in the stand until the platens were properly positioned at the stand above and below the wood members supported by the stand. After operation of the press to drive the nailing plates into the wood members, the operator backed the press out of its working position to its entry/exit position, and then moved the press sidewise as illustrated at G toward the next successive stand. Thus, it can be seen that in accordance with the present invention the direct sidewise movement of the press into and out of its operating position A (see FIG. 10) at the various stands requires fewer movements of the press by the operator than the in-and-out movement of the press required by the prior art apparatus (FIG. 11). Accordingly, this direct movement of the press facilitates fabrication of the wood structure and enables more rapid and economical production of wood structures. Moreover, the proximity sensing means further markedly improves the, production effectiveness of this truss fabricating apparatus in that it functions-to insure rapid and reliable positioning of the press at each stand.

In view of the above, it will be seen that the several objects of the invention are achieved and other advantageous results attained.

As various changes could be made in the above constructions and methods without departing from the scope of the invention, it isintended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrated and not in a limiting sense.

What is claimed is:

1. The method of fabricating wood structures utilizing a C-shaped press and having an upper platen and a lower platen which are relatively movable toward and away from one another for driving nailing plates into two or more wood members from above and below comprising:

supporting wood members, which are to be nailed together at joints to form a wood structure, on a plurality of stands arranged at said joints, with clearance below the wood members for movement of the lower platenof the press underneath said wood members;

bringing the press into an operating position at one of said stands with its lower platen below the wood members;

operating the press to drive nailing plates into the wood members without applying any substantial net upward or downward force thereto and then opening the press;

moving the press generally laterally with respect to the press substantially sidewise out of said one stand and over to the next successive stand, maintaining it adjacent the wood member supported by these stands as it is moved and entering it substantially sidewise into said next successive stand to bring it into its operating position at said next successive stand for driving nailing plates into the wood members;

again operating the press to drive nailing plates into the wood members and then opening the press; and

repeating the latter two steps as the press is moved bounding the structure to be fabricated, and the aforesaid steps are carried out along each of said lines around the structure. b

3. The methodof claim 1 wherein operation of said press is prevented unless said press is at ,an operating position at one of said stands.

4. Apparatus for fabricating wood structures comprising a series of stands for holding wood members which are to be secured together at joints by nailing plates to form a wood structure, said stands being arranged at said joints, each such stand having a support and means cantilevered relative to the support for holding wood members with clearance therebelow, a C- shaped press having an upper platen and a lower platen which are relatively movable toward and away from I one another for driving nailing plates into the wood members from above and. below, said press being mounted to permit vertical movement during driving the nailing plates into the wood members, and means mounting said press for movement of the press into an operating position at one of said stands for driving nailing plates into the wood members held by said one stand, for movement in a generally lateral direction with respect to the press substantially sidewise out of its operating'position at said one stand, and over to the next successive stand, and into its operating position at said next successive stand with said press being maintained substantially adjacent the wood members supported by these stands as it is moved, and for driving said nailing plates into the wood members from above and below without exerting any substantial net upward or downward force on the wood members by the platens, the said clearance below the holding means being sufficient for lateral passage of the lower platen of the press below the holding means.

5. Apparatus as set forth in claim 4 wherein said stands supporting the wood members are arranged on lines bounding the wood structure to be fabricated.

6. Apparatus asset forth in claim 4 wherein said holding means includes a holder cantilevered outwardly from said support for holding a lower nailing plate to be driven into the wood members from below, said cantilevered holder being carried by the support for upward and downward movement relative to the support.

7. Apparatus as set forth in claim 4 wherein said holding means comprises two cantilever arms in sideby-side spaced relation adapted to support wood members in position for being secured together by the nailing plates at a location between the arms, said support being adapted for lateral entry of the lower platen of the press from one side or the other thereof below said cantilever arms to its operating position between said arms with the plane of the top surface of said arms spaced from the top surface of the lower platen a distance sufficient to accommodate a nailing plate arranged with its teeth pointing upwardly for being driven into the wood members from below, the cantilever arms being laterally spaced from one another a distance greater than the width of the lower platen of the press for entry of the lower platen of the press between the arms when the lower platen is moved upwardly to drive a nailing plate upwardly into the wood members.

8. Apparatus as set forth in claim 7 wherein said holding means further includes a holder for holding a lower nailing plate to be driven into the wood members from below, said holder being .carried by the support for upward movement between said arms by the lower platen of the press from a lowered retracted position below the plane of the top surface of said arms to drive a nailing plate positioned thereon into the wood members from below.

9. Apparatus as set forth in claim 8 wherein said support includes a base, said arms being cantilevered forward over the base and spaced above the base for the lateral entry of the lower platen of the press from one side or the other of the stand between the base and the arms.

10. Apparatus as set forth in claim 9 having means for supporting said holder movable upwardly and downwardly at one side of the base constituting the back of the base, said holder being a plate cantilevered forward over the base, the lowered retracted position of the holder plate being generally below the level of the top surface of said arms a distance sufficient to accommodate a nailing plate with its teeth pointing upwardly for being driven into the wood members from below and being spaced above the base a distance sufficient for entry of the lower platen of the press.

11. Apparatus as set forth in claim 10 wherein said holder plate supporting means comprises a pair of vertical rods secured to said holder plate with the latter extending forwardly from the upper ends of said rods, and guide means carried by the stand for guiding said holder plate during movement between its lowered retracted position and a raised operative position in which a nailing plate held thereby is driven into wood members from below.

12. Apparatus as set forth in claim 11 wherein said base has a top and said support includes supporting means for said arms extending upwardly above the top of the base at the back thereof.

13. Apparatus as set forth in claim 12 wherein said supporting means for said arms comprises a hollow wall extending upwardly from the base at the back thereof, said arms extending forwardly over the base from the sides of said wall at the top thereof and being located above the top of said wall, said apparatus further having a bar at the level of said arms extending between the back ends of said arms, said rods being movable up and down in said wall and the holder plate extending forwardly therefrom over the top of said wall.

14. Apparatus as set forth in claim 11 wherein said guide means comprises a pair of grooved rollers carried by said support for each of said rods, said rollers of each pair being disposed on opposite sides of their respective rod for guiding the rod as said holder plate is moved between its lowered retracted position and said raised position for driving said nailing plate into the wood members from below.

15. Apparatus as set forth in claim 11 wherein said guide means comprises a pair of rollers carried by each of said rods, said rollers being engageable with a portion of said support for guiding the rod as said holder plate is moved between its lowered retracted position and said raised positionfor driving said nailing plate into the wood members from below.

16. Apparatus as set forth in claim 4 further comprising means for preventing operation of the press unless the press is at an operating position at one of said stands. 1

17. Apparatus as set forth in claim 16 wherein the last-said means includes proximity sensing means responsivev to movement of the press into its operating position at each of said stands.

18. Apparatus as set forth in claim 17 wherein said proximity sensing means comprises a proximity switch actuable in response to a magnetic field of a predetermined strength, and means for producing a magnetic field of sufficient strength to actuate said proximity switch when said press is at its operating position at one of said stands thereby to permit operation of the press,

19. Apparatus as set forth in claim 18 wherein said proximity switch is carried by said press and said field producing means is a magnet carried by each of said stands so that with the press positioned at its operating position at a stand, said proximity switch being actuated by the field of the magnet carried by the stand.

20. Apparatus as setforth in claim 19 which further includes a circuit for initiating movement of said press platens toward one another for driving nailing plates into the wood members, said proximity switch being connected in said circuit whereby said press may be operated only when the press is at its operating position at one of said stands and said proximity switch is actuated to energize said circuit.

21. Apparatus as set forth in claim 20 wherein said circuit includes at least one manually operable switch, said proximity switch being serially connected in said circuit with said manually operable switch whereby said press may be operated only when the press is at its operating position at one of said stands and both of said switches are actuated.

22. Apparatus for fabricating wood structures comprising a series of stands for holding wood members which are to be secured together at joints by nailing plates to form a wood structure, said stands being arranged at said joints, a press having an upper platen and a lower platen which are relatively movable toward and away from one another for driving nailing plates into the wood members from above and below, means mounting said press for generally lateral movement of the press substantially sidewise into and away from an operating position at each of said stands, and means for preventing operation of the press unless the press is at an operating position at one of said stands.

23. Apparatus as set forth in claim 22 wherein each such stand includes a support and holding means cantilevered relative to the support for holding wood members with clearance therebelow.

24. Apparatus as set forth in claim 23 wherein said holding means includes a holder cantilevered outwardly from said support for holding a lower nailing plate to be driven into the wood members from below, said cantilevered holder being carried by the support for upward and downward movement relative to the support.

25. Apparatus as set forth in claim 22 wherein the last said means includes proximity sensing means responsive to the movement of the press into an operating position at each of the stands.

26. Apparatus as set forth in claim 25 wherein said proximity sensing means comprises a proximity switch actuable in response to a magnetic field of a predetermined strength, and means for producing a magnetic field of sufficient strength to actuate said proximity switch when said press is at its operating position at one of said stands thereby to permit operation of the press.

27. Apparatus as set forth in claim 26 wherein said proximity switch is carried by said press and said field producing means is a magnet carried by each of said stands so that with the press positioned at its operating position at a stand, said proximity switch is actuated by the field of said magnet carried by the stand.

28. Apparatus as set forth in claim 2 which further includes a circuit for initiating movement of said press platens toward one another for driving nailing plates into the wood members, said proximity switch being connected in said circuit whereby said press may be operated only when the press is at its operating position at one of said stands and said proximity switch is actuated to energize said circuit.

29. Apparatus as set forth in claim 28 wherein said circuit includes at least one manually operable switch, said proximity switch being serially connected in said circuit with said manually operable switch whereby said press may be operated only when the press is at its operating position at one of said stands and both of said switches are actuated.

P UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. i r Dated July 23 1274 Invenmflg) Walter G.. Moehlenpah It is certified that error appears in the above-identified patent and that said Lette ts Patent are hereby corrected as shown below:

!" Column 1, 'line'45, "light" should read --tight--. Column 8 line 9, "liquid" vshould read -fluid--. Column 14, claim 28, line 1, "claim '2" should read --claim 27--.

Signed and sealed this 29th day of October 1974.

(SEAL) Attest:

McCOY M. CIBsON JR. c. MARSHALL DANN Atte'sting Offlce r Commissioner of Patents

Claims

1. The method of fabricating wood structures utilizing a Cshaped press and having an upper platen and a lower platen which are relatively movable toward and away from one another for driving nailing plates into two or more wood members from above and below comprising: supporting wood members, which are to be nailed together at joints to form a wood structure, on a plurality of stands arranged at said joints, with clearance below the wood members for movement of the lower platen of the press underneath said wood members; bringing the press into an operating position at one of said stands with its lower platen below the wood members; operating the press to drive nailing plates into the wood members without applying any substantial net upward or downward force thereto and then opening the press; moving the press generally laterally with respect to the press substantially sidewise out of said one stand and over to the next successive stand, maintaining it adjacent the wood member supported by these stands as it is moved and entering it substantially sidewise into said next successive stand to bring it into its operating position at said next successive stand for driving nailing plates into the wood members; again operating the press to drive nailing plates into the wood members and then opening the press; and repeating the latter two steps as the press is moved between successive stands thereby to nail additional wood joints.

2. The method of claim 1 wherein wood members are supported on a plurality of stands arranged on lines bounding the structure to be fabricated, and the aforesaid steps are carried out along each of said lines around the structure.

3. The method of claim 1 wherein operation of said press is prevented unless said press is at an operating position at one of said stands.

4. Apparatus for fabricating wood structures comprising a series of stands for holding wood members which are to be secured together at joints by nailing plates to form a wood structure, said stands being arranged at said joints, each such stand having a support and means cantilevered relative to the support for holding wood members with clearance therebelow, a C-shaped press having an upper platen and a lower platen which are relatively movable toward and away from one another for driving nailing plates into the wood members from above and below, said press being mounted to permit vertical movement during driving the nailing plates into the wood members, and means mounting said press for movement of the press into an operating position at one of said stands for driving nailing plates into the wood members held by said one stand, for movement in a generally lateral direction with respect to the press substantially sidewise out of its operating position at said one stand, and over to the next successive stand, and into its operating position at said next successive stand with said press being maintained substantially adjacent the wood members supported by these stands as it is moved, and for driving said nailing plates into the wood members from above and below without exerting any substantial net upward or downward force on the wood members by the platens, the said clearance below the holding means being sufficient for lateral passage of the lower platen of the press below the holding means.

6. Apparatus as set forth in claim 4 wherein said holding means includes a holder cantilevered outwardly from said support for holding a lower nailing plate to be driven into the wood members from below, said cantilevered holder being carried by the support foR upward and downward movement relative to the support.

7. Apparatus as set forth in claim 4 wherein said holding means comprises two cantilever arms in side-by-side spaced relation adapted to support wood members in position for being secured together by the nailing plates at a location between the arms, said support being adapted for lateral entry of the lower platen of the press from one side or the other thereof below said cantilever arms to its operating position between said arms with the plane of the top surface of said arms spaced from the top surface of the lower platen a distance sufficient to accommodate a nailing plate arranged with its teeth pointing upwardly for being driven into the wood members from below, the cantilever arms being laterally spaced from one another a distance greater than the width of the lower platen of the press for entry of the lower platen of the press between the arms when the lower platen is moved upwardly to drive a nailing plate upwardly into the wood members.

8. Apparatus as set forth in claim 7 wherein said holding means further includes a holder for holding a lower nailing plate to be driven into the wood members from below, said holder being carried by the support for upward movement between said arms by the lower platen of the press from a lowered retracted position below the plane of the top surface of said arms to drive a nailing plate positioned thereon into the wood members from below.

15. Apparatus as set forth in claim 11 wherein said guide means comprises a pair of rollers carried by each of said rods, said rollers being engageable with a portion of said support for guiding the rod as said holder plate is moved between its lowered retracted position and said raised position for driving said nailing plate into the wood members from below.

16. Apparatus as set forth in claim 4 further comprising means for preventing operation of the press unless the press is at an operating position at one of said stands.

17. Apparatus as set forth in claim 16 wherein the last-said means includes proximity sensing means responsive to movement of the press into its operating position at each of said stands.

18. Apparatus as set forth in claim 17 wherein said proximity sensing means comprises a proximity switch actuable in response to a magnetic field of a predetermined strength, and means for producing a magnetic field of sufficient strength to actuate said proximity switch when said press is at its operating position at one of said stands thereby to permit operation of the press.

20. Apparatus as set forth in claim 19 which further includes a circuit for initiating movement of said press platens toward one another for driving nailing plates into the wood members, said proximity switch being connected in said circuit whereby said press may be operated only when the press is at its operating position at one of said stands and said proximity switch is actuated to energize said circuit.