Aug. 4, 1964 11w. LASSAHN 3,143,335
CLANPING DEVICE FOR CONSTRUCTING FLOORING, DECKING, AND THE LIKE Filed Nov. 1, 1962 2 Sheets-Sheet 1 INVENTOR. DEAN W. LASSAHN W g WP ATTORNEY Aug. 4, 1964 D. w. LASSAHN 3,143,335
CLAMPING DEVICE FOR CONSTRUCTING FLOORING, DECKING, AND THE LIKE Filed Nov. 1, 1962 2 Sheets-Sheet 2 INVENTOR. DEAN W. LASSAHN um M ATTORNEY United States Patent 3,143,335 CLAMPING DEVICE FOR CQNSTRUCTENG FLGQRING, DECKENG, AND Til- 2E LIKE Dean W. Lassahn, 4270 McKeiier Lane, Palo Alto, Calif. Filed Nov. 1, 1962, Ser. No. 234,675 6 Claims. (Ci. 254-111) This invention relates to clamping devices and a method for constructing flooring and the like, and more particularly to a construction clamp useful in the construction business to urge abutting edges of a plurality of boards into close contact until they can be fastened in place.
Heretofore it has been customary, in the laying of subfiooring, covering or decking during the construction of buildings and the like, to first place a wooden board across the stringers and urge the same tightly against the previously laid and fastened board to provide good tonguein-groove engagement, and thereafter fasten the same in place by nailing the board to the stringers. To assure good engagement between abutting edges which may be plain or tongue and groove, nails are driven into the board at an angle so that, as the nails penetrate into the stringers, they would laterally draw the board against the abutting edge of the previously placed and fastened board.
In this manner, each individual plank is fastened in place separately, requiring a construction worker to move along the total length of each board to drive in nails at each stringer before positioning and fastening the next board. Also, for long boards, it has been found necessary to utilize two construction workers, so that boards could be more properly positioned prior to being nailed down. This method of laying boards is time consuming and therefore expensive, particularly when more than one construction worker is required to perform the task.
Also it has been found that the lateral draw provided by inclining the nails is in most instances insufiicient to obtain tightly overlapping tongue and groove engagement, particularly when the boards are not seasoned and have warped under exposure to the elements prior to utilization.
It is therefore a primary object of this invention to provide a clamping device and method of construction which will make the laying of boards for sub-flooring, decking, covering and the like much more economical to thereby sharply reduce construction costs.
It is another object of this invention to provide a method and a means for more economically laying sub-flooring, decking, covering and the like which requires only a single construction worker to fasten them in place to thereby sharply reduce the manpower requirements.
It is a further object of this invention to provide a method of laying boards for a variety of uses and a means for firmly urging abutting edges of a large number of boards into intimate contact with one another so that they may be fastened in place by a single person all at one time.
It is still another object of this invention to provide method and means for assuring a more intimate contact between abutting edges of boards to thereby form a superior sub-floor, floor, deck, cover or the like.
It is still a further object of this invention to provide a clamp which is rugged in construction, reliable in operation, has a gripping mechanism for engaging stringers or the like which is rapidly adjustable for spacing, capable of tight gripping, and easily disengaged.
Other objects and a better understanding of this invention may be had by reference to the following description, taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a perspective view of clamping devices constructed in accordance with this invention clamped to a 3,143,335 Patented Aug. 4, 1954.
stringer and urging boards into intimate abutting edge contacts;
FIG. 2 is a top view of the clamping device shown in FIG. 1;
FIG. 3 is a cross sectional view taken along line 33 of FIG. 2; and
FIG. 4 is a top view showing the employment of two clamping devices constructed in accordance with this invention clamped to stringers and urging boards into intimate edge contact.
Referring now to the drawings, and particularly to FIG. 1 thereof, there is shown theclamping device 10 of this invention releasably clamped to astringer 12 for urging a plurality ofboards 14, 15 and 16 into close edge contact for subsequent fastening tostringers 12, 18 and 19. Also shown is an actuating means, such as ahydraulic pressure system 20, and a flexiblehydraulic line 21 forconnecting pressure system 20 to clampingdevice 10.
Clampingdevice 10, as best shown in FIGS. 2 and 3, comprise a bracket generally indicated as 22, a pair ofgripping elements 23 and 24, and an extensible plunger means 25. Bracket 22 is formed of achannel member 26 having abase 27 and a pair ofside walls 28 and 29; and anangle member 30 welded or otherwise rigidly fastened across the forward open end ofchannel member 26.Angle member 30 projects laterallypast side walls 28 and 29 on both sides ofchannel member 26 and has ahorizontal side wall 31 and avertical side wall 32 which extends across the forward open channel end.
The lower surface ofbase 27 and ofside wall 31 provide a seating surface forseating bracket 22 uponstringer 12 as best seen in FIG. 1. Such a construction ofbracket 22 is inexpensive requiring only a short length ofchannel 22 and a short length ofangle 30 which are standard structural steel shapes readily available.
Of course, as will be immediately apparent to those skilled in the art,bracket 22 may be formed as a single piece with a smooth horizontal seating surface and with extensions near the forward end integrally cast or forged toside walls 28 and 29.
Gripping elements 23 and 24 comprise circular discs having aperipheral surface 34 either formed with blunt teeth or knurled or serrated in order to ensure positive or biting engagement with the side surface ofstringer 12 and to causegripping elements 23 and 24 to roll and not to slip.
To provide cam surface performance ofperipheral surfaces 34,gripping elements 23 and 24 are eccentrically journalled about a pair ofparallel pivot shafts 36 and 37 respectively.Pivot shafts 36 and 37 may be rigidly mounted toside wall 31 and so spaced that gripping elements engage opposite side surfaces ofstringer 12. To securegripping elements 23 and 24 topivot shafts 36 and 37 respectively a clip ring may engage a groove formed at their respective end portions in the conventional manner.
Gripping elements 23 and 24 are so placed that upon engagement withstringer 12 they will bite into the stringer side surfaces when a force is applied tobracket 22 tending to move the same in a backward direction. When a force is applied tobracket 22 in the forward direction, however, grippingelements 23 and 24 swing away and immediately release their grip on stringer 12 to form a releasable engagement.
Extensible plunger means 25 may be formed of a conventional hydraulic ram having acylinder housing 40 and a moving piston andpiston rod combination 42. Apad 44 is preferably connected to the free end ofpiston rod 42 to provide a more extended surface over which the pressure is distributed and applied to board 14.Pad 44 may be faced with a relatively softresilient surface 45 so that board 14 is not damaged whenpad 44 is forced against its outer edges.Fac ng 45 becomes particularly important when board 14 has a tongue and groove edge to which further boards are to be joined.
Plunger means 25 is preferably, but not necessarily, pivotally journalled about apivot pin 46 welded or otherwise alfixed to opposite ends tochannel side walls 28 and 29.Cylinder housing 40 is formed with a T'-joint pipe extension 48 forengaging pivot pin 46.
' Plunger means 25 may be a conventional, single acting, ram having a high pressure inlet for hydraulic fluid at 50 to whichflexible hose 21 is connected. Instead of hydraulic actuating fluid high pressure gas may be used in conjunction with pneumatic plunger means. Also it is within the contemplation of this invention to utilize a plunger means in the form of a screw jack operated either manually, electrically or hydraulically in a conventional manner.
Side wall 32 functions as a spacer bar which supportspiston rod 42 parallel to the surface ofstringer 12 when plunger means 25 is in its operating position. In thismanner side wall 32 is dimensioned to properly position plunger means 25 for best operation. It has been found that a slight downward slant ofpiston rod 42 with respect to the surface of stringer 12 in the forward direction prevents the boards from being lifted off the stringers.
In operation, the stringers are fastened in place in the customary manner. Thereafter a single board forming the end board of a subfioor, floor, decking, roof or the like is fastened to the stringers in the usual way to form a starting point for the construction method now to be described. In case the floor or the like abuts a wall or an existing abutment, it is unnecessary to fasten the first board in place.
Thereafter, as best seen in FIG. 4, a plurality of boards, such as 60, 61 and 62, are loosely laid across thestringers 63, 64, 65 and 66 parallel to one another. At least one, but preferably more than one, clamping device is seated upon selected stringers such as 63 and 66 and is moved forward untilpad 44 engages the edge ofboard 62. Thereafter,gripping elements 23 and 24 are rotated for engagement with the stringer side walls and actuator means is operated to forcepiston 42 forward, the gripping elements preventing motion tobracket 22 in the backward direction.
Piston 42 is moved in the forward direction until all boards such as 60, 61 and 62 are in close contact with one another so that their edge separation is a minimum. In case of tongue-and-groove edges, a complete penetration of the tongue into the groove is desired. After intimate edge contact is established,piston 42 is locked into its extended position such as by shutting off hydraulic flow and the boards are nailed into place in any desirable order. In other words, once the boards are properly positioned, all boards may be first nailed to one and then to the next stringer, orboard 62 may first be fastened in place to releaseclamping devices 19 for adding the next section of boards.
After the boards (at least outer board 62) is fastened in place,piston 42 is unlocked and retracted a sufficient distance to permit plunger means 25 to be pivoted upwards and out of the way. Thereafterbracket 22 is urged in the forward direction by a sharp blow with a hammer or the like which releasesgripping elements 23 and 24 which allows removal ofclamping device 10.
There has been described a clamping device for and a method of constructing flooring, decking or the like which is very economical, fast, and which enables a single person to construct such a floor. Furthermore, the resulting floor is superior since more intimate contact between abutting edges of the boards is assured.
What is claimed is:
1. A clamping device for releasably engaging a stringer member and for urging a plurality of boards, supported crosswise upon the stringer member, into intimate contact with one another and comprising:
(a) bracket means for seating upon said stringer member;
(19) gripping elements pivoted upon parallel pivot axes on said bracket means at opposite sides of said stringer member, each gripping element having a cam surface engaging an opposite face of said stringer member;
(c) extensible plunger means pivotally mounted to said bracket means for pivotal movement between an operating and a disengaging position about a pivot axis at right angles to the pivot axes of said gripping elements, the axis of extension of said plunger means when in said operating position being at right angles to the gripping element pivot axes and the plunger means pivot axis, and the direction of extension being selected to urge said cam surface into closer engagement with said stringer member;
(d) a pad afiixed to the end of the extensible portion of said plunger means for contact with a crosswise supported board; and
(e) actuating means for extending the extensible portion of said plunger means against said plurality of boards.
2. A clamping device in accordance with claim 1 in which said bracket means is formed of an open channel having upwardly extending side walls and an angle member affixed across the forward end of said channel, the side of said angle member across the open forward end of said channel being dimensioned to guidingly support the extensible portion of said plunger means when in said operating position and the other side of said angle member projecting beyond the side Walls of said channel for forming the supports of said gripping elements.
3. A clamping device in accordance with claim 1 in which each of said gripping elements comprises an eccentrically mounted disc having a rough peripheral surface for engaging said stringer member.
4. A clamping device for engaging a stringer member and for urging a plurality of boards laid across the stringer member into intimate edge to edge contact comprising:
(a) a bracket for seating upon said stringer member having a base, a pair of side walls and a forward end wall;
(b) gripping elements pivoted upon parallel pivot axes on said base on opposite sides of said stringer member, each gripping element having a cam surface engaging an opposite face of said stringer member;
(c) hydraulic plunger means pivotally mounted to said bracket for pivotal movement between an operating and a disengaging position about a pivot axis perpendicular to said side walls, said plunger means having an extensible piston engageable by said forward end wall, for guidingly supporting said plunger means in said operating position, said cam surfaces being orientated to tightly clamp to said stringer member when said clamping device is urged backwards and to release said stringer member when said clamping device is urged forward, the height of said forward end wall being selected to support said piston substantially horizontally in such operating position; and
(d) a hydraulic fluid pressure system for actuating said plunger means in a forward direction whereby said piston engages said boards to urge the same into intimate edge contact.
5. A clamping device releasably attachable to a stringer or the like to which boards are to be secured for urging abutting edges of a plurality of boards or the like into close contact, said clamping device comprising:
(a) a bracket means having a seating surface slidable over the stringer and a forward end;
(b) a pair of cam elements pivotally mounted to said bracket means below said seating surface, said cam elements having a gripping peripheral surface for engaging opposite sides of said stringer when said bracket means is moved backwards;
(c) a hydraulic ram means pivotally mounted to said bracket means for pivotal movement between an operating and a disengaging position about a pivot axes at right angles to the pivot axes of said cam elements, the axis of extension of said ram means being substantially parallel to the direction of elongation of said stringer when said ram means is in said operating position, the extensible part of said ram means projecting past the forward end of said bracket means for operative engagement with said boards; and
(d) actuating means for extending said extensible plunger means to urge said boards into close contact.
6. A clamping device releasably attachable to a stringer or the like to which boards are to be secured for urging abutting edges of a plurality of boards or the like into close contact, said clamping device comprising:
(a) a bracket means having a seating surface slidable over the stringer and a forward end;
(b) a pair of cam elements pivotally mounted to said bracket means and below said seating surface, said cam elements having a gripping peripheral surface for engaging opposite sides of said stringer, when said bracket means is moved backwards;
(c) a hydraulic ram means pivotally mounted to said bracket means for pivotal movement between an operating and a disengaging position about a pivot axis at right angles to the pivot axes of said cam elements, the axis of extension of said ram means being substantially parallel to the direction of elongation of said stringer when said ram means is in said operating position, the forward end of said bracket means guidingly supporting the extensible part of said ram means in said operating position;
(d) extended pad means affixed to the end of the extensible part of said plunger means for contact with a board; and
(e) actuating means for urging the extensible part of said ram means against said board to thereby urge said plurality of boards into close contact.
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