DE2557393A1 - DEVICE FOR HOLDING THE WOODEN PARTS OF A WOODEN CONSTRUCTION TO BE MANUFACTURED - Google Patents

Description

Device for holding the wooden parts of a to be manufactured

Wooden structure

The invention relates to devices for producing wooden structures, Such as prefabricated wooden roof trusses or the like., And relates in particular to a device which the Holds wooden parts in their position, which are to be connected to one another by nail plates, which are driven into the wooden parts at their connection or abutment points.

In conventional devices for the production of wood trusses, several stands are used, which can be adjusted independently of one another can be moved into positions that correspond to the connection points,

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ie correspond to the joints of the wooden parts of the binder to be produced. Each time a binder in a new size, or a new type of binder is to produce d r device, these stands have to be moved to new positions so as to support the joints of the wooden parts of the product to the new binder. This adjustment of the stands may be necessary several times in a day if different truss sizes and configurations are made.

According to US Pat. No. 3,068,484, a row of uprights is displaceable along a guide track so that they can be optionally arranged at different points along the lower chord of the truss in order to support the wooden parts of the truss at the joints. This stand can on the guide path at any desired location along the same be clamped detachably _e Other stands, which are displaceable on the ground, of the upper belt can longitudinally be arranged of the binder and fixed in a desired position by means of telescoping support members to the uprights, the previously longitudinally have been positioned on the guideway and clamped to it.

Another apparatus, such as that described in U.S. Patent 3,068,483, uses multiple hydraulic presses, one for each junction of the tie. In one of the embodiments shown in this patent (Figs. 30-32), some of these presses are mounted on stands which have rollers so that the stands can be easily rolled into a desired position on a steel base plate.

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These stands have an electromagnetic hold-down so that the stand is in one position by energizing the magnet can be held. Such a magnetic hold-down allows simple and infinitely variable positioning the stand, however, it has been found that after the stands are positioned and the electromagnets energized, the stands do so tend to swing outwards to a variable extent when the wooden parts are firmly clamped and jogged on the stands (resulting in irregular trusses) and that the uprights tend to become gradually horizontal during manufacture to move so that after a number of bundles have been made, production must be stopped and the uprights repositioned Need to become. These magnetic hold-downs therefore do not hold the stand in its desired position in a completely satisfactory manner fixed.

One of the objects of the invention is to provide an apparatus for manufacturing of wooden structures in which at least some of the uprights to adapt to virtually any truss configuration are easily adjustable and can be easily and positively held in any desired position. The invention creates one Device in which magnetic hold-down devices are used, which are caused by irregularities in the magnetizable bottom surface on which the stands stand, or by forces that act on the stands and try to move them, not disadvantageous to be influenced. By the device according to the invention, the wobbling of the stand when wooden parts are placed and on The uprights are clamped tightly, erroneously eliminated, and the uprights are prevented from moving with respect to the truss

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gradually shift horizontally outwards. The invention provides an apparatus that is easy to use, reliable in operation and is economical to manufacture. Further features and advantages of the invention emerge from the following statements.

The device according to the invention contains several stands for supporting the wooden parts at their connecting points and means for releasably clamping the wooden parts in their position so that they can be connected to one another by nail plates. At least one of the stands is easily on a magnetizable floor surface in a desired position to support the wooden parts of the manufactured Slidable wooden construction. This stand has a side facing outward as a whole from the binder, which forms the outside of the stand, and has a side opposite this side, which forms the inside of the stand. This stand also has a first horizontal axis of symmetry that extends as a whole from the outside to the inside of the stand, and a second generally horizontal axis of symmetry perpendicular to the first axis. The stand also has means for Support the stand on, which are two support feet, one on each side of the first axis, which are offset with discrete areas on the floor next to the outside of the stand can be brought into contact. It's on this stand Means are provided for lifting the stand from the floor surface so that the stand can be moved from one position to another can. The stand also has optional excitable electromagnetic hold-down devices that can be brought into contact with the floor surface, to magnetically clamp the stand to the bottom surface so that

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the stand is held positively in a desired position on the floor surface and withstands forces caused by the wooden parts are exerted, which tend to tilt the stand outwards with respect to the wooden structure. The hold-down device is located on the side of the second axis next to the inside of the stand, so that when the stand is on the Floor surface is supported by the magnet and by the support feet, the magnet, when excited, holds on to the floor surface and frictionally holds the stand in its position on the floor and effectively withstands the tilting forces exerted on the stand.

An embodiment of the invention is shown in the drawings and is described in more detail below. Show it:

Fig. 1 is a plan view of one with several

adjustable movable stands provided device according to the invention for the production of a wood tie,

Fig. 2 is an enlarged side view of the

Line 2-2 in Fig. 1 from one of the uprights carrying a wooden part,

Figure 3 is a front view of the stand

of Fig. 2,

Fig. 4 is an enlarged bottom view of the

Stand,

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Fig. 5 is a vertical sectional view on the

Line 5-5 in Fig. 4, and

6 is an enlarged vertical sectional view

ο on the line 6-6 in Fig. 4 to

rotated, some parts are broken away for the sake of clarity.

In the various figures, the same parts have the same reference numerals.

The device according to the invention, which is designated in its entirety by the reference number 1, holds wooden parts W of a wooden structure S to be produced in their position so that they can be connected to one another at the joints or joints between the wooden parts. In particular, the device 1, as shown, holds the struts and chord parts 3 and 5 of a roof truss in their position, in which they are connected to one another by nail plates 7, which are inserted into the wooden parts at their joints from above and below by a hydraulic press ( not shown), which can be moved from joint to joint. The device contains several stands 9 for supporting the wooden parts at their joints and for holding the wooden parts in place before they are connected to one another by nail plates 7. The uprights 9 have means, which are designated in Fig. 1 in their entirety by the reference numeral 11, for releasably clamping the wooden parts in fixed relation to the uprights in the position in which the wooden parts are connected to one another by the nail plates. For example, it can be the clamping devices

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are quick-release clips, as they are in the US PS 3,068,484 are described which clamp the wooden parts in place on the stands and enable the completed trusses can be easily removed from the stands can.

The device 1 also contains a magnetizable bottom surface 13 (e.g. several butting steel plates) on which the uprights 9 are easily moved to a desired position can be, which corresponds to the joints of a binder to be produced. Each of the stands that are on the magnetizable bottom displaceable iat, has a first and a second horizontal axis X-X and Y-Y (see. Fig. 4), which each other at right angles intersect and can be viewed as a whole as the horizontal axes of symmetry of the stand. The stand is related arranged on the tie to be produced so that the adjoining belt part 5 of the tie as a whole from a transverse side of the stand to the other (as shown in Fig. 1). The first axis X-X runs entirely from the front or outside to the rear. or inside of the stand, while the second axis Y-Y is generally perpendicular to the axis X-X. The wooden part W is in Fig. 4 is shown parallel to the Y-Y axis, but it is clear that the pieces of wood can form an angle with the Y-Y axis. Two support feet 14a, 14b are provided on the stand, namely one on each side of the X-X axis. Each of these feet is immediately below them on a small, limited area of the ground 1 3 can be brought into contact and forms a support device for the stand. Lifting devices, or in particular ... rolling devices,

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which are designated in their entirety by 15 are provided on each stand. These ron devices are between one lowered or extended position (see. Fig. 5 and 6), in which the rolling devices on the magnetizable floor 1 3 roll and the stand is raised and thus clear of the floor so that it can easily be rolled from one position to another can be, and a raised or retracted position (as shown in Figs. 2 and 3) adjustable in which the Stand rests on the floor. It is clear that other devices, such as a compressed air lifting system in the U.S. Patent No. 3,728,958, can be used to raise the stands, allow them to be moved, and to other positions can be brought.

It is important that when the wooden pieces W are put together in preparation for the press-fitting of the nail plates, one there is a firm contact between each of the wooden parts at the joint. In order to achieve this, the striving of the manufactured Binders driven into place, sometimes by hammering, so that considerable outward forces are exerted on the binder which tend to tip the stands away from the truss. Because of minor changes in the dimensions of the wooden parts these outwardly directed forces acting on the binder can change from binder to binder. Also be frequent the joined tie parts, if they are clamped in preparation for the pressing in of the nail plates, are further preloaded, to bend the lower chord slightly upwards so that a fixed curvature is created in the tie so that after completion of the tie the tie straps, if the expected structural loads act on them, are straight.

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mm Q μ,

As a result, of course, the total outwardly directed forces acting on the uprights are further increased.

The stand also has in its entirety with the reference number 17 designated magnetic hold-downs, which on the bottom 13 can be brought into contact with the magnetizable floor Hold magnetically so that the stand is firmly held in any desired position on the steel floor and effectively withstands the forces exerted on the stand which attempt to tilt the stand outward relative to the truss. The hold-down devices 17 contain, as shown, at least one and preferably two optionally excitable electromagnets 19a and 19b. As shown in Fig. 4, the magnets 19a, 19b are located on opposite sides of the X-X axis, and both magnets are on the side of the Y-Y axis next to the Inside of the stand (i.e. facing the truss). This is particularly important because when the rolling devices 15 are in their raised, retracted position and when the stand is on the floor 13 by the feet 14a, 14b on its outside and through the magnets 19a, 19b is supported on its inside, the magnets, when they are excited, hold on to the floor magnetically to hold the stand in place with a force fit and around the withstand tilting forces exerted on the stand.

In particular, each one on the magnetizable base 1 contains 3 movable ones Stand 9 has a rigid frame with vertical side parts 21, a base 23, which are arranged at a mutual distance from one another. Parts 25 for supporting the wooden parts on the stand and one

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Receiving plate 27 below the parts 25 for receiving a lower nail plate. This receiving plate can be moved upwards towards the wooden parts by the press in order to drive the lower nail plate into the wooden parts from below. Horizontal struts 29 span the space between the side parts 21, and the various parts are attached to one another, for example by welding. In terms of the details of the base 23, the stand is generally similar to the stand described in U.S. Patent 3,068,484 referred to above. Further details about the stands and about the above-mentioned hydraulic press, which is movable from stand to stand in order to drive nail plates into the wooden parts, can be found in this US patent specification. As shown in Fig. 4, the stand base 23 at the ends of the stand includes the bottom plates 31a, 31b, which extend parallel to the axis XX, and struts 33a, 33b at the front and rear of the stand, respectively, which extend parallel to the Extend the YY axis. As best shown in Figures 4 and 6, the feet 14a, 14b are hollow and attached to the base 23, such as by welding. A third foot 35, which is essentially the same as the feet 14a, 14b, is fastened on the axis XX next to the inside of the stand and is also welded to the base 23. These feet are metal tubes with a square cross-section or the like. Specifically, the feet 14a, 14b are attached to the bottom plates 31a and 31b, respectively, on opposite sides of the axis XX on the front or outside of the stand, and the foot is attached to the strut 33b attached to the back of the stand on the XX axis. As FIG. 6 shows, the magnets 19a, 19b are adjustably attached to the base 23 by means of screws 36. The undersides of the magnets are arranged at the level or slightly below the undersides of the feet 14a, 14b and 35, so that

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it is ensured that the magnets touch the floor 13 even if the floor is wavy.

The rolling devices 15 are shown as ball roller units, such as those manufactured by Matthews Conveyor Company of Ellwood City, Pennsylvania, which are a Have ball roller 37 which can rotate freely about any axis so that the stand on the floor 13 moves freely in any direction can be. As shown in FIG. 6, each ball roller 37 is mounted in a housing 39 that has an overall circular cross-section Has. A guide block 40 with an overall square cross-section is attached to the upper end of the housing 39 and this The housing and the guide block are between an extended position (cf. Fig. 6), which corresponds to the above-mentioned lower, extended position of the rolling devices 15 in which the ball roller 37 protrudes below her foot and touches the ground 13, and movable to a raised position in which the ball caster is removed from the floor. This latter position corresponds to the above-mentioned raised, retracted position of the ball devices 15. It can be seen that when retracted Rolling of the stands 19 on the floor 13 by the feet 14a, 14b and is supported by the magnets 19a, 19b, since the magnets and these feet are on opposite sides of the center of gravity of the stand (which is located near the intersection of the axes X-X and Y-Y) and there the magnets preferably protrude slightly above the plane formed by the undersides of the feet 14a, 14b and 35 downwards. To this This way, the contact of the magnets with the floor 13 is ensured. regardless of the unevenness or rolling

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of the soil. Thus, the air gaps between the undersides of the magnets and the floor are minimized and the magnets 19a, 19b exert their maximum available holding force on the floor 1 3.

Each ball roller 37 is raised and lowered relative to its foot 14a or 14b or 35 by means of a cam-operated linkage arrangement, which is designated in its entirety by the reference number 41. This linkage arrangement causes the rollers to shift simultaneously between their raised, retracted position and their lowered, extended position. The linkage assembly includes a shaft 43 which is journalled in guide blocks 40 of the front ball roller units. Openings 44 Cvgl. Fig. 5) in the sides of the feet 14a and 14b enclose the shaft 43, these openings being substantially larger than the diameter of the shaft. Cam plates 55 are mounted on the shaft next to the feet 14a and 14b and can be brought into contact with stationary cam followers which are attached to the feet and the base 23 of the stand 9 next to the openings 44. When the shaft 43 is rotated in one direction (i.e., clockwise in FIG. 6), the cam disks 45 each lie against their cam follower 46 and cause the shaft to move downwards with respect to the openings 44, which causes a relative movement between the guide blocks 40 and the feet 14a and 14b to cause movement of the rollers from their raised, retracted position to their lowered, extended position. It can be seen that when the rollers are in their lowered, extended position, the weight of the stand is carried by the cams 45. As best shown in Figure 6, the

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Cam disks 45 flat surfaces 47, which on their curve scanners 46 can be brought into abutment when the rollers are in their lowered, extended position, whereby the rollers be held in a form-fitting manner in their lowered, extended positions. A stub shaft 48 is in the guide block 40 of the roller in the rear foot 35 rotatably mounted. This stub shaft extends on the side of the foot 35 through there existing enlarged openings 44. Like the shaft 43, the stub shaft 48 carries cams 45 on the outside of the foot 35, which can be brought into contact with stationary cam scanners 46 are. The stub shaft 48 is connected to the shaft 43 by means of crank arms 49 and 50, which are attached to the shaft 43 and to the Shaft 48 are attached, and by a link 51 which is pinned to the ends of the crank arms. Consequently When the shaft 43 rotates via the crank handle 53, the rollers in the front feet 14a and 14b and simultaneously with causes them the role in the rear foot 35 to be

to move with the shaft between its raised, retracted and its lowered, extended positions.

It can be seen that the above-mentioned outwardly directed forces, which are applied to the stand 9 and clamped Wooden parts W of the binder S are exercised, strive to tilt at least some of these uprights outward and around the outer edges the front feet 14a and 14b to rotate and the magnets 19a, 19b to lift off the floor 13. Under normal operating conditions, in which the bottom 13 is clean and free of grease or others Impurities is affecting the coefficient of friction of the floor

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reduce, the friction of the feet 14a, 14b, which sit on the floor, is sufficient to withstand the horizontal forces exerted on the stand by the placed and clamped wooden parts. However, under other conditions, for example when the floor 13 is dirty, the friction of the outer feet on the floor may not be sufficient to fully withstand the horizontal forces acting on the stand. It is precisely in these situations that the advantages of the invention become particularly clear.

Especially when the magnets 19a, 19b next to the inside of the stand 9 are arranged, it can be seen that they are from the outer edges of the feet 14a, 14b, around which the stand tilts, are away. This minimizes the vertical holding forces that must be exerted by the magnets in order to prevent the stands from tilting and thus maximizes the holding force (and consequently the friction) of the magnets on the floor. The frictional force between the magnet and the floor and the frictional force between the feet 14a, 14b and the floor is sufficient to counter the horizontal forces, the on the stand by the applied and clamped wooden pieces be exercised to withstand even under adverse operating conditions. Thus, the need is the binder production Interrupting periodically to reposition the stand eliminated.

In addition, the fact that the stand 9 on its outside by feet 14a, 14b and on its inside by magnets 19a, 19b is supported and the magnets cling to the floor, prevents the stand from wiggling on the magnet. at

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known stands with magnetic hold-down devices, as described in the above-mentioned US Pat. No. 3,068,483, the stand is under certain conditions (i.e. with uneven ground) supported solely by the magnet, while the rest of the stand is not in contact with the ground. Thus, when placing and clamping wooden parts W, these known stands can move back and forth on the magnet, until the outer parts of the stand touch the ground again. This wobbling movement of the stand can cause the The top of the stand moves significantly (e.g. about 6 mm), with the result that irregular or Binder outside the tolerance are produced. Since according to the invention of the stand by the magnets 19a, 19b its inside and through the feet 14a, 14b on its front is supported, the stand is never supported by the magnets alone and thus the wobbling movement of the stand is increased prevents the magnet.

Electricity is supplied to the electromagnets 19a, 19b through power lines 55 (see. Fig. 1) supplied. A switch 57 (see FIG. 3) on each stand 9 is used to selectively energize and de-energize the electromagnets 19a, 19b on the stand. Thus, the stand can if it has been brought to the desired location on the floor 13, can be easily locked to the floor by simply flipping switch 57.

A guide rail 59 (see FIGS. 1, 2 and 5) may be attached to the floor 13 to assist in aligning a number of uprights 9 along a straight line , such as is shown in FIG

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for aligning uprights along the lower chord of a truss may be desirable. When the outer surfaces of the feet 35a, 35b of each stand are in contact with the rail 59, the alignment of the lower chord stands is ensured.

It can be seen that not all of the stand 9 of a device must be equipped according to the invention with magnetic hold-downs. For example, have in a device similar to that described in U.S. Patent 3,068,484 noted above is, only the uprights supporting the upper chords are magnetic hold-down devices, since the uprights are longitudinally along the lower chord their guide rail are adjustable and can be clamped to the same. The invention is also in devices similar to that in U.S. Patent 3,068,483, in which each column supports a hydraulic press for driving the nail plates into the wooden parts at each joint.

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Claims (8)

Patent claims: τ 1 .1 device for holding the wooden parts of a wooden structure to be produced, for example the belt parts and the struts of a wood tie, in their position so that connections can be made at the joints between the wooden parts, for example by driving nail plates from above and below the wooden parts, characterized by several stands for supporting the wooden parts at their joints Means for releasably clamping the wooden parts in place so that they can be connected to one another by the nail plates, through a magnetizable floor surface, at least one of the uprights on the floor surface being easily movable into a desired position in order to support the wooden parts of the wooden structure to be produced, wherein one side of this upright, which faces outwards from the truss as a whole, forms the outside of the upright, and another side opposite this side forms the inside of the upright, this upright having a first horizontal axis of symmetry extending from it Outside to its inside, and having a second generally horizontal axis of symmetry perpendicular to the first axis, and means for supporting the stand comprising two feet, one on each side of the first axis and with offset, limited areas of the floor adjacent the outside of the stand in contact b ar, means for raising the upright so that it comes free from the bottom surface, to move the rack from one position to another, and optionally energizable electromagnetic hold-down device, with 609826/0332 the bottom surface can be brought into contact in order to hold onto the bottom surface magnetically, so that the stand in a desired position on the floor surface is held firmly and the forces exerted on it by the wooden parts resists, which tend to tilt the stand with respect to the wooden structure to the outside, with the hold-down on the inside of the second axis are arranged next to the inside of the stand, so that when the stand passes through on the floor surface the hold-down device is supported next to one side of the stand and by the feet next to the outside of the stand, this hold-down device, when they are excited, grasp the floor area and hold the stand in its position on it with a force fit and the effectively withstand tilting forces exerted on the stand. 2. Apparatus according to claim 1, characterized in that the hold-downs are two electromagnets that are next to the inside of the stand, one on each side of the first axis. 3. Apparatus according to claim 1 or 2, characterized in that the lifting device contains rolling devices, which consist of a lowered, extended position in which they over the support devices and the magnets protrude downward to come into contact with the floor surface, thereby the stand lift off the floor surface so that the stand can be moved from one position to another, and one raised, retracted position are movable in which the support devices and magnets are in contact with the floor surface. 6 0 9 8 2 6/0332 4. Apparatus according to claim 3, characterized in that the support device includes a third foot which is arranged on the first axis next to the inside of the stand. 5. Apparatus according to claim 4, characterized in that the feet are each hollow and that the rolling devices within the hollow feet for displacement to their lowered, extended position and their raised, retracted position are arranged. 6. The device according to claim 5, characterized by a linkage arrangement, which connects the rolling devices together so that the sliding of the rolling devices between their lowered, extended position and their raised, retracted position takes place simultaneously. 7. Device according to one of claims 3 to 6, characterized in that the rolling devices are ball rollers which are rotatable about each axis so that the stand on the rollers on the floor can be moved in any horizontal direction when the rollers are in their lowered position , extended position. 8. Device according to one of claims 1 to 7, characterized by several stands, which are similar to the aforementioned one stand, whereby the stand is easily repositioned on the floor surface Can be made so that wooden structures with different configurations can be easily manufactured. 609826/0332 Blank page