EP0321440B1 - Method and device for driving nails - Google Patents

Abstract

The method for driving nails into materials to be connected, the nails being connected by wires or the like to form a band and being able to be formed into a roll of nails spirally in one plane or a flat cone, is characterised by the following features: the nail to be driven in is supplied to the tool head in such a way that it protrudes slightly from the lower end of the tool head, so that, on striking, the nail tip is the first part to come into contact with the material to be connected, the driving-in energy being applied by a striking member which in the process overcomes the action of at least a weak spring urging it away from the nail head, so that it is separated from the nail head in the rest position. The device according to the invention is characterised in that a nail-guiding unit (2) positions the next nail to be driven in in the device in such a way that the nail tip projects beyond the underside of the head (2g), and in that the device has a striking member (1) which strikes the nail head and the striking surface of which is separated from the nail head in the rest position, a spring (4) pushing the striking member away from the nail. <IMAGE>

Description

The invention relates to a method and a device for driving nails into materials to be connected, the nails being connected to a band by wires or the like and being able to be formed spirally into a nail roll in a plane or a flat cone.

Such processes are carried out by devices see also US-A-2 667 639- which are generally referred to as nailers, drum nailers, strip nailers or pin nailers and which have the task of making roofing felt, wood foils, cardboard, paper, composite panels, etc. connect with each other.

By connecting the nails to each other using wires or similar. constant nail spacing is achieved which, in conjunction with automatic feed devices provided in the nailers, enables a significantly increased capacity compared to conventional nailing using a classic hand hammer.

The well-known nailers with automatic feed of the nails apply the driving energy by compressed air or electrically (e.g. electromagnet). In such devices, the nail feed also takes place with the energy used for driving in. A major disadvantage of these devices is the absolutely necessary connection of the nailer to an energy store or an energy supply unit.

This makes nailing so difficult in certain spatial conditions that such devices are almost never used for various purposes, for example in construction for fastening roofing felt. Their main area of application is therefore when working under precisely defined conditions, such as nailing boxes at workplaces equipped for this and the like.

Under the first-mentioned conditions, the classic method with the hand-held nail is used, which is first fixed - "tacked" - with a careful stroke and then with one or more strokes, depending on the nature of the surface and the Length and strength of the nail is driven.

Various attempts have been made to rationalize this manual nailing. One such attempt is disclosed in US-A-4,434,929. According to the device shown there, an essentially conventional hammer has a nail magazine for loose nails, the pins of which lie close together in a guide slot, wherein they are displaced by head thickness relative to one another in the direction of the pin, and furthermore the heads have a recess which extends as far as the The edge of the pin is sufficient to allow the pins to lie close together.

In operation, the nail package is pushed forward by a pin size with a handle and then the foremost nail is pressed down by a lever in order to be attached to the ground during the subsequent stroke. As a result, the nail is driven in by the user of the hammer with the hammer head in the usual way.

To drive in the next nail, the handle is actuated again and the next nail is attached with the following stroke, whereupon the game starts again.

This device is essentially unsuitable for practical operation for a number of reasons: the use of the required special nails entails high costs, the linear magazine makes it difficult to see the nail location and the handle which is to be operated separately is a hindrance to the driving strokes. In addition, the nail is fed through the split hammer head, which makes it more expensive to manufacture and also causes problems with the driving strokes.

FR-PS 1 596 749 discloses a device using nails which are actually not nails but one-legged staples. These nails have a T-shaped profile in one direction and a narrow rectangular profile in the direction perpendicular to the first direction and are glued together with their T-shaped outline, which enables a feed similar to that in staple machines.

In this device, the nail is attached with a first blow, the adhesive bond to the next nail breaking, whereupon the hammer is rotated by the user by 180 ° along its stem axis and the nail is driven in with the other end of the head with one or more strokes . To set the next nail, the user turns the hammer over again and staples the next nail.

This device also requires the use of special nails, which moreover have a shape which makes driving in more difficult and, owing to the shape of the nail head, does not permit the use of this device for a whole range of fields of application. For example, it is not possible to nail roofing felt with these nails, because on the one hand the head has too little space to enable stable fastening of the roofing felt and on the other hand the penetration of water along the side of the head, which does not project in all directions around the nail stick Pin is not prevented.

From US-A-1 024 390 a device is known in which conventional nails in a slot-like, curved magazine pass under the influence of gravity through a slotted hammer head and are guided by a spring-loaded sliding device to the end face of the hammer head and there by the sliding device and a spring-loaded holding device can be held. The nail head lies well on the face of the hammer head.

When striking, the following happens: First the glider hits the surface and moves upwards along the nail and hammer head against the action of the spring, then the tip of the nail hits the surface and is driven in by the hammer head lying on the nail head, although almost at the same time the holding device opens and is moved radially outwards on the ground.

If the underside of the holding device runs flat with the underside of the hammer head, the next nail reaches its area and when the hammer is lifted off, the holding device and the sliding device are each pressed down again by their spring, whereupon the circuit is closed.

With such a nailer, it is not possible to work overhead or on a vertical wall, since the nail feed only works when nailing on approximately flat horizontal surfaces. Furthermore, a noticeable part of the impact energy is lost due to the two spring-loaded parts, the holding part being highly likely to damage the surface due to its radial movement. Such damage must be avoided in particular when applying insulating mats or parts of all kinds.

Due to the complicated nature of the nail supply, the device according to US-A-1 024 390 is prone to failure. In particular, the nail is guided around the front edge of the head in two directions orthogonal to one another, the risk of getting caught being extremely great.

The path of the hammer head between the first touch of a part connected to it and the end of the driving-in process is considerably longer than the nail. With a given impact energy, this means a significant reduction in the available driving force. A shortening of this way is not possible because the nail is above the face of the hammer head is fed through the head, and therefore enough meat must remain below the feed channel to the front to ensure the mechanical stability of the hammer.

In addition, the driving force is not exerted by a real blow, since the nail head lies snugly against the hammer head during the entire stroke movement. The nail is actually just pushed in.

The object of the invention is to create a method and a device for driving in nails, in which the driving energy is applied manually and the nails are advanced without the user doing anything. Common nails, i.e. Nails with a head that protrudes in all directions over the nail pin can be used and it should be possible for magazines to store the nails without having to tension springs or other energy stores. In addition, the size, mass and shape of the device are intended to be ergonomically correct and enable the nails to be driven in with just one stroke, without having to "tack" beforehand.

Furthermore, the method is to use a real "hammer blow", that is to say that a striking body strikes the essentially stationary nail and the impact energy reaches the tip as a compression wave and drives the nail there.

The method according to the invention consists in feeding the nail to be driven into the tool head in such a way that it protrudes slightly over the lower end of the tool head, so that when hitting the nail tip is the first part to touch the material to be connected, the driving energy being applied by an impact body which this overcomes the effect of a weak spring that pushes it away from the nail head so that it is at a distance from the nail head in the rest position.

The corresponding device can comprise a handle, an upper part with a striking body and a nail magazine with a feed device. The impact body can be connected to the handle and upper part of the device so that their kinetic energy is used as driving energy.

In one embodiment of the method, the advancing movement of the next nail is carried out during the return movement of the striking body by the spring tensioned during the impact. The implementation or linking of this body return movement with the feed movement can be done in different ways e.g. by means of scenes and claws or by means of additional springs.

By the inventive measure to position the nail to be driven in the device on the one hand so that it protrudes with its pointed end from the surface of the device facing the surface and already expose the nail head to the action of the driving body, it is possible to use nails similarly as before, staples to be set in one fell swoop, although this was previously considered impossible due to the geometry of the nails.

A completely unexpected peculiarity of the method according to the invention lies in the fact that the above nail makes it possible to keep the path of the striking body between the impact on the nail head and the end of the driving-in movement shorter than the nail is long. The difference is due to the partial penetration of the nail tip due to the kinetic energy of the nail and the connection with the other nails. The difference is small, but a comparison with the prior art shows the size of the improvement.

The tool head striking the substrate does not move relative to the substrate, which means that the forces that occur are powerless and that there is no damage to the substrate.

The invention further relates to a device for performing the method according to the invention.

This consists essentially of a hammer handle, which is connected to a hammer head which has the required mass for the driving-in process. These parts can also be made in one piece using plastic injection molding. The device also has a preferably one-piece magazine, nail guide and driver guide unit, which is articulated by means of a bolt on the hammer handle. The bolt runs perpendicular to the axis of the handle and at least approximately perpendicular to the axis of the nail that is driven in next.

The hammer handle and the hammer head on the one hand and the magazine, nail guide and driver guide unit on the other hand are preferably pushed apart by a spring when the nail device is at rest until it stops. A driver is articulated in the hammer head, for example by a bolt with play or a corresponding jaw-shaped guide.

In a variant, it is also possible to guide the driver only in the driver guide unit or to store it displaceably and to press it with a spring against an abutment in the hammer head. The abutment can also only be the underside of the hammer head. The spring can also take on the task of pushing apart the hammer head and the driver guide unit.

The driver protrudes into a channel of the driver guide unit and is intended to drive the nail to be driven into the ground by the impact energy of the hammer head and handle that it transmits. It has a crescent-shaped recess on the side on which the nails are fed in, in order to grasp and drive in only the foremost and also the next nail, which already projects into the driver channel with part of its head.

Furthermore, a slide or spring lever is mounted on the magazine, nail guide and driver guide unit, which pushes the next nail either on the head or on the shaft via a resilient feed claw when a nail has been driven in. In a side opening gate for inserting the nail band there is a retaining claw which prevents the nail band from sliding back when the feed claw moves backward.

This retaining claw can be designed as a leaf spring, the angled leg preferably having a length such that it serves as a guide against loads in the vertical or horizontal direction. The retaining claw can be attached in the gate or in the area of the nail guide, it can also be designed with a joint that enables movement in the horizontal direction. The gate itself should preferably be opened by at least 90 ° in order to allow easy magazine loading. It is held in its closed position via a snap or snap connection.

It is also possible to design the bottom of the magazine to be foldable in order to allow magazine storage.

A rigid or spring-loaded part for centering the nail roller can be provided in the lid or bottom of the magazine part.

When using a feed lever, a link is preferably provided, through which the feed claw is brought out of its guide area even with a small dead stroke of the driver, and on the other hand, after driving the nail in, the feed movement of the claw for the next nail only shortly before top dead center of the Driver. Such an arrangement increases the operational safety of the device.

The same can be achieved when using a feed spring lever through a corresponding geometry of the spring lever if the angled ends of the spring lever Intervene directly between the nail heads, the feed corresponds to the nail division on the nail band. In this case, a dead stroke of the driver is not required for the lever movement. The pretension of the spring lever presses the nail to be driven into the driver guide at the top dead center of the driver and the driver can move freely vertically between the angled ends of the spring lever.

A link rigidly connected to the hammer head or the driver pushes the spring lever away from the driver by one nail division during the driving-in process, the angled end of the spring lever springing open laterally over the nail head located in this area and sliding away. The spring lever thus has a pretension in at least two planes and is preferably supported laterally during the springing open of the angled ends when sliding over the nail head.

• Fig. 1 eine geschnittene Seitenansicht einer erfindungsgemäß ausgebildeten Nagelvorrichtung mit Vorschubhebel;
• Fig. 2 zeigt die Vorderansicht mit Vorschubhebel;
• Fig. 3 zeigt den Schnitt III-III der Fig. 1;
• Fig. 4 zeigt einen Teilschnitt der Nagel- und Treiberführung mit einem Vorschubfederhebel;
• Fig. 5 zeigt die Draufsicht auf Fig. 4.

The invention is explained in more detail with reference to the drawing: It shows the

• Figure 1 is a sectional side view of a nail device designed according to the invention with a feed lever.
• Fig. 2 shows the front view with feed lever;
• Fig. 3 shows the section III-III of Fig. 1;
• Fig. 4 shows a partial section of the nail and driver guide with a feed spring lever;
• FIG. 5 shows the top view of FIG. 4.

1 essentially comprises the impact body 1, which consists in one piece of the hammer handle 1a, the hammer head 1b, the joint 1c, in which the magazine, nail guide and driver guide unit 2 is mounted; in the hammer head 1 b sits the driver bearing, which can be designed as a pin bearing 1d, or, as is known, as a jaw guide.

The magazine, nail guide and driver guide unit 2 consists essentially of the drum magazine 2a, at least approximately in the form of a hollow cylinder with the spring or rigidly attached nail roller guide 2b and the snap or snap connection 21 for the gate 3; the drum magazine 2a forms a part with the nail guide 2b, which is formed as at least one side wall with a groove 2d and has one or more openings 2e for guiding the feed claw 6b. The driver guide 2f forms a part with the impact part 2g and the nail guide 21 as well as the drum magazine 2a, which is preferably made of cast or plastic injection molding, with wear inserts on the mechanically stressed surfaces, e.g. the driver guide 2f, the nail guide 21, the drum magazine surfaces etc. The magazine bottom 2h and the magazine upper part 2j can be conical in order to ensure optimal guidance of the nail roll.

The gate 3 is pivotally mounted on the driver guide 2f or on the nail guide 21 with a hinge-shaped joint 3a (FIG. 3) and can be opened by at least 90 ° to insert the nail roll. In the gate 3 or in the nail guide 21, the retaining spring 3b is attached, which can also be designed as an articulated retaining claw; the correspondingly angled leg 3c of the retaining spring 3b serves as a guide in the gate 3 or in the nail guide 21 against loads in the vertical direction.

Impact body 1 and the magazine, nail guide and driver guide unit 2 are mounted in the joint 1c, where a spring 4 with correspondingly designed legs according to FIG. 1 is also attached to the joint bolt and, in the idle state of the nailing device, the impact body 1 and the magazine , Nail guide and driver guide unit 2 apart at an angle of 5 ° -35 °. If the driver 5 is at its bottom dead center, the magazine, nail guide and driver guide unit forms 2 to the horizontal plane an angle of 5 ° -15 °. The driver 5 is movably suspended in the bearing 1d and has a round shaft 5a with a cross-sectional area which is larger than the nail head area. The driver shaft 5a is made with a crescent-shaped recess 5b in order to ensure that the driver 5 slides past the following nail head. The driver head 5c is designed for a pin or jaw bearing.

The nail tape can basically be fed using two lever variants; Variant 1 (Fig. 1) is a gear or lever system, variant 2 (Fig. 4) is a spring lever system. In the case of the feed lever 6 shown in FIG. 1, this is designed as a link lever, a pin 1e or a corresponding to a link block being similar. is connected to the hammer head 1b. The feed link lever 6 is mounted on one or both sides of the magazine, nail guide and driver guide unit 2 and has a link 6a incorporated, which gives the necessary nail feed with a small dead stroke of the driver 5.

When driving the driver 5, the nail band is only advanced when the driver 5 has passed the edge 2k of the driver guide 2f. The feed claw 6b is guided in the side wall opening 2e of the nail guide 21 and can be fastened to a leaf spring 6c which is connected to the cranked part 6d of the feed link lever 6. the leaf spring 6c and the cranked part 6d can be replaced by a piece of spring wire attached to the feed link lever 6, which engages in a vertical bore of the feed claw 6b. The feed claw 6b engages the nail shaft in this described first lever variant.

Fig. 4 shows as a second lever variant a feed spring lever 7, which is attached to the magazine, nail guide and driver guide unit 2 and by its bias the nail to be driven to the Wall of the driver guide 2f presses. the angled ends 7a of the feed spring lever 7 engage on both sides between the first and second nail heads and are driven in by a sliding block or a roller 1f, which is connected to the impact body 1 or to the driver 5, by a nail distance (pitch) in the direction of Drum magazines 2a pressed. When the magazine, nail guide and driver guide unit 2 is swung open, the next nail is pushed into the driving position. The spring lever 7 has a prestress in at least two planes, which can be supported laterally by guides 2 m when springing up via the nail head diameter.

An asymmetrical variant of a spring which has the same effect as the lever part 6b in FIGS. 2, 3 is shown in dash-dot lines in FIG. 4. The spring part 6b supports the nail in the area of its shaft. The asymmetry is due to the space requirement of the retention claw.

To drive in, the operator grasps the nail device according to the invention on the hammer handle 1a, lifts it to the required height and strikes the parts to be connected with the necessary energy. The impact surface 2g strikes and the magazine, nail guide and driver guide unit 2 moves at an angle to the impact body 1; the base of the driver shaft 5a hits the nail head and drives the nail in, the connecting wires breaking to the subsequent nail. During the driving-in process, the feed claw 6b or the spring lever 7 with its angled ends 7a makes a movement in the direction of the drum magazine 2a because of the backdrop 1f.

When the nail device is lifted, the magazine 4, the nail guide and driver guide unit 2 is pivoted away from the striking body 1 again by the spring 4 and guides the feed of the next nail via the feed link lever 6 or the feed spring lever 7 with the feed claw 6b or the angled ends 7a of the feed spring lever 7. During the driving-in process, the retaining spring 3b holds the nail band in position, supports the next nail on the shaft, and is pushed out of engagement by the higher-pretensioned feed claw 6b when the driving-in movement is advanced.

To insert the nail roll, the gate 3 is opened and the nail band is inserted into the magazine, nail guide and driver guide unit 2 and engaged between the feed claw 6b and the retaining spring 3b; however, the nail band can also be attached to the driver guide 2f and snapped onto the feed claw 6b.

Claims (2)

1. A method of driving nails into materials to be joined, which comprises a combination of the following features:
      the nails have a head projecting on all sides beyond the spike;
      the nails are interconnected by wires or the like to form a strip and are arranged in a magazine;
      the nails are disposed at least approximately parallel to one another but are offset in the direction of the spike, the nail to be driven in is guided in the tool head in such a way that it protrudes slightly beyond the lower end of the tool head so that, when driven in, the nail spike is the first part to contact the material to be joined;
      the driving-in force is applied by a driving member which in doing so overcomes the action of at least a weak spring which endeavours to press it away from the nail head, so that, in the inoperative position, it is spaced apart from the nail head;
      the force for the feed movement of the nail strip originates from at least one spring tensioned during the impact;
      the feed movement of the nail strip is derived from the spring-actuated relative movement between the driving member and the magazine.
2. An apparatus for carrying out the method according to Claim 1, characterised by a combination of the following features:
      the apparatus has a hammer shaft (1a) with a hammer head (1b);
      a magazine, nail-guiding and driver-guiding unit (2) is secured movably thereto, preferably hinged;
      the nail to be driven in can be positioned by the nail-guiding unit (2b) in the apparatus so that the nail spike projects beyond the underside (2g) of the apparatus;
      the apparatus has a driving member (1) which is connected with the hammer shaft (1a) or with the hammer head (1b) or is in one piece therewith;
      the driving member strikes the nail head and, in its inoperative position, its impact surface is spaced apart from the nail head, at least one spring (4) pressing the driving member away from the nail;
      during the driving-in of the nail into the materials to be joined, the spring (4) can be tensioned by the relative movement between the hammer shaft (1a) or the hammer head (1b), on the one hand, and the magazine, nail-guiding and driver-guiding unit (2), on the other hand;
      the magazine, nail-guiding and driver-guiding unit (2) is movable relative to the head (1b) of the apparatus by the spring (4), in which case it preferably pivots it about a hinge (1c).

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