Device for a user to secure a workpiece

A device (1) for a user to secure a workpiece (2) that is positioned on a substrate (3) during the processing of the workpiece (2) with a hand-held power tool. A stepping element (4) has a stepping surface (10) via which the user applies a holding force, and that also has a placement surface (11) for placing the device (1) onto the workpiece (2).

This claims the benefit of German Patent Application DE 10 2011 017506.7, filed Apr. 26, 2011 and hereby incorporated by reference herein.

The invention relates to a device for a user to secure a workpiece.

BACKGROUND

Hand-held power tools are used to cut elongated workpieces to length. The term “hand-held power tools” refers below to power tools such as, for example, angle grinders and chainsaws that an user holds in his hands during the work. Electric as well as gasoline-powered hand-held power tools are known. The tool selected depends, among other things, on the material of the workpiece that is to be cut to length. Chainsaws are used mainly for tree trunks and wooden beams, whereas angle grinders are used primarily for stone curbs and steel pipes.

In actual practice, the workpieces that are to be cut to length are not clamped during the work, but rather are secured by the user who puts his foot onto the top of the workpiece. This securing technique entails the risk of foot injuries since the foot is close to the cutting site and thus to the moving work tool. The risk of foot injuries is especially high at the beginning and end of the cutting procedure since the work tool can move in an uncontrolled manner.

SUMMARY OF THE INVENTION

It is an object of the present invention is to reduce the risk of foot injuries when elongated workpieces are cut to length by means of hand-held power tools.

The present invention provides a stepping element that has a stepping surface via which the user applies a holding force, and that also has a placement surface for placing the device onto the workpiece. The stepping surface ensures that the holding force is applied uniformly to the workpiece. Moreover, it reduces the risk that the user's foot might slip during the work. The stepping surface is preferably made of a non-skid material or provided with a coating of a non-skid material. The use of a non-skid material reduces the risk that the user's foot will slip off the stepping surface during the securing procedure.

Preferably, the stepping element is connected via a connecting element to a retaining element that has a contact surface for the securing device to make contact with the workpiece. The retaining element ensures that the securing device is in contact with the workpiece, not only via the placement surface of the stepping element, but also via another contact surface. Thanks to the additional contact surface on the workpiece, the workpiece that is to be secured is prevented from rolling or slipping away under the securing device when the holding force is applied.

Especially preferably, the retaining element is configured so as to be adjustable relative to the stepping element. Here, the position of the contact surface of the retaining element and/or the angle between the stepping element and the retaining element are adjustable. Since the retaining element is adjustable, the securing device can be adapted to different workpieces.

In a preferred embodiment, the stepping element is connected via a connecting element to a support element with which the device can rest on the substrate. The support element ensures that the securing device is anchored on the substrate and the workpiece that is to be secured is prevented from moving or slipping away.

The support element here consists especially preferably of a first section facing the stepping element and of a second section facing the substrate, whereby the first and second sections are adjustable relative to each other using a length adjustment means. Thanks to this length adjustment, the securing device can be adapted to different workpieces. Moreover, using the length adjustment means, the stepping element can be aligned in such a way that the stepping surface is slanted by an inclination angle relative to the horizontal plane. The inclination of the stepping surface improves the ergonomics for the user. Inclination angles of about 5° to 20° are ergonomically advantageous.

In a preferred embodiment, the stepping element and the support element are each arranged at an angle of 100° to 120° relative to the retaining element. This embodiment is especially well-suited for securing workpieces having a circular or rounded cross section. Here, the length adjustment means of the support element is used to adapt the securing device to different diameters and to set the inclination angle of the stepping surface.

In an alternative preferred embodiment, the stepping element and the support element are arranged at an angle of 90° relative to the retaining element, and the stepping surface is slanted by an inclination angle of about 5° to 20° relative to the placement surface. This embodiment is especially well-suited for securing workpieces having a rectangular cross section. Here, the securing device is adapted to different heights and widths of the workpieces using the length adjustment means of the support element and by means of the adjustability of the retaining element.

In a preferred embodiment, a protective guard is provided that is connected to the stepping element and that is arranged on the side of the stepping element associated with the hand-held power tool during the work. The protective guard reduces the risk of foot injuries for the user since the working area of the hand-held power tool is shielded by the protective guard.

In a first variant, the stepping element and the protective guard are non-detachably connected to each other. The non-detachable connection reduces the possibility of improper use by the user. Moreover, This ensures that the user will not dismantle the protective guard. Preferably, a protective guard is provided on both sides of the stepping element so that the securing device can be used by left-handed as well as right-handed persons.

In a second variant, the stepping element and the protective guard are detachably connected to each other, whereby the protective guard can be connected to the stepping element on the right-hand and/or on the left-hand side of the stepping element. The detachable connection has the advantage that the securing device can be used by left-handed as well as right-handed persons, and the user can arrange the protective guard on the side of the stepping element associated with the hand-held power tool during the work.

DETAILED DESCRIPTION

FIGS. 1A-Cshow a first embodiment of a device1according to the invention for securing a workpiece on a substrate while an user is working the workpiece with a hand-held power tool.

FIG. 1Ashows the securing device1during the securing procedure of a tubular workpiece2on a substrate3. In the case of workpieces with a circular or rounded cross section, there is a risk that the workpiece will roll away on the substrate during the work. The securing device1has the task of preventing the workpieces2from rolling away or moving on the substrate3.

The securing device1includes a stepping element4, a support element5and a retaining element6. Here, the stepping element4and the support element5are connected to each other by a first connecting element7, and the stepping element4and the retaining element6are connected to each other by a second connecting element8.

In order to protect the foot of the user during the work, the securing device1has a protective guard9that is connected to the stepping element4and that is arranged on the side of the stepping element4associated with the hand-held power tool during the work. The cut is made on the side of the protective guard9, so that the securing device1is suitable for a right-handed person and not suitable for a left-handed person. In order for the securing device1to also be used by left-handed persons, a protective guard9can be provided, for example, on both sides of the stepping element4.

The stepping element4has a stepping surface10via which the user applies a holding force to the securing device, and, opposite from the stepping surface10, a placement surface11for placing the securing device1onto the workpiece2. The stepping surface10is provided with a coating12made of a non-skid material or, as an alternative, it is made of a non-skid material.

FIGS. 1B and 1Cshow the securing device1in a front view (FIG. 1B) and in a rear view (FIG. 1C) on the support element5, without the tubular workpiece that is to be secured. The support element5is configured so as to be adjustable between a minimum and a maximum length using a length adjustment means13, and it consists of a first section14facing the stepping element4and of a second section15with which the securing device1rests on the substrate3. The second section15has a first foot16A and a second foot16B on the side facing the substrate3. Depending on the substrate3, the second section15can have different feet16A,16B in order to firmly secure the securing device1on the substrate3.

The first and second sections14,15of the support element5are adjustable relative to each other. In the first section14, there is a slot17in which a fastening means18is located. The fastening means18consists of a screw19and a nut20. When the nut20is tightened, the first and second sections14,15are firmly connected to each other, whereas when the nut20is loose, the second section15is adjustable.

The retaining element6serves to firmly secure the workpiece2during the work and to prevent the workpiece2from slipping away. The retaining element6has a contact surface21with which the securing device1rests on the workpiece2. Tubular workpieces are firmly secured via the placement surface11of the stepping element4and via the contact surface21of the retaining element6.

In the embodiment of the securing device1shown, the stepping element4, the first section14of the support element5, the retaining element6and the protective guard9are configured monolithically as a metal bracket without adjustment possibilities. The stepping element4, the first section14of the support element5and the retaining element6are arranged relative to each other in such a way that the securing device1is suitable for securing a prescribed spectrum of tubular workpieces. The securing device1is adapted to different pipe diameters using the length adjustment means13of the support element5.

FIGS. 2A, B show the securing device1in a side view during the processing of a first tubular workpiece22having a first pipe diameter D1of 30 cm (FIG. 2A) and of a second tubular workpiece23having a second pipe diameter D2of 50 cm (FIG. 2B).

In order to be able to work tubular workpieces having a pipe diameter of about 30 cm to 50 cm, securing devices are suitable that have, for example, an angle α of about 115° between the stepping element4and the support element5, and an angle β of about 120° between the stepping element4and the retaining element6.

Since the angles α, β between the stepping element4and the support element5, and between the stepping element4and the retaining element6, are not adjustable, the securing device1is adapted to the pipes22,23using the length adjustment means13. The length of the support element5is set in such a way that the stepping element4and the retaining element6each lie against the pipe22,23, and the securing device1is supported on the substrate3via the feet16A,16B.

It is ergonomically advantageous if the stepping surface10is not arranged horizontally but rather at an inclination angle relative to the horizontal plane. The inclination of the stepping surface10improves the ergonomics for the user during the work. Angles of about 5° to 20° have proven to be ergonomically advantageous. The user can set the inclination angle of the stepping surface10using the length adjustment means13of the support element5and can adapt it to his needs.

The inclination of the stepping surface10is set differently when the workpieces22,23are secured. This can be seen in the fact that the angle γ between the support element5and the substrate3is different. When the first workpiece22is secured, the angle γ1is smaller than the angle γ2when the second workpiece23is secured.

FIGS. 3A, B show a second embodiment of a device31according to the invention for securing a workpiece on the substrate3during the work by a user.

FIG. 3Ashows the securing device31during the securing procedure of a rectangular workpiece32that is configured in the form of a porous concrete stone. In the case of rectangular workpieces, thanks to the larger placement surface on the substrate3, there is less risk that the workpiece will roll away on the substrate3than is the case with workpieces having a circular or rounded cross section. Nevertheless, there is risk of injury to the user, especially at the beginning and end of the cutting procedure, due to uncontrolled movements of the work tool. The lighter the workpiece, the greater the risk that the workpiece will slip away on the substrate during the work.

The securing device31consists of a stepping element34, a support element35and a retaining element36. In order to be able to process workpieces32having different heights and widths, the support element35and the retaining element36are configured so as to be adjustable. The support element35consists of a first and a second section37,38that are adjustable relative to each other using a length adjustment means39. The securing device31is adapted to the height of the workpiece32by means of the adjustable length of the support element35.

Like the stepping element4of the securing device1, the stepping element34has a stepping surface40and a placement surface41. The stepping surface40and the placement surface41, however, are not arranged parallel to each other, but rather the stepping surface40is slanted relative to the placement surface41by an inclination angle. The inclination of the stepping surface40improves the ergonomics for the user during the securing procedure. Inclination angles of about 5° to 20° have proven to be ergonomically advantageous.

FIG. 3Bshows the securing device31in an enlarged, three-dimensional view of the retaining element38without the rectangular workpiece32that is to be secured. The retaining element36ensures that the securing device31is in contact with the workpiece32, not only via the placement surface41of the stepping element34, but also via another contact surface42. The contact surface42is oriented at an angle of 90° relative to the placement surface41of the stepping element34.

The retaining element36includes a contact element43having the contact surface42and a sliding element44. The sliding element44runs in two guide grooves45A,45B that are fastened between the stepping surface40and the placement surface41of the stepping element34. The position of the sliding element44can be locked on the stepping element34or relative to the stepping element34by means of a locking device46.

The securing device31is adapted to the width of the workpiece32on the basis of the adjustable position of the contact surface42. The dimensions of the support element35and of the retaining element36are selected in such a way that the securing device31is suitable for a prescribed spectrum of rectangular workpieces32. In order to be able to use the securing device31to secure four-sided workpieces that do not have a rectangular cross section, the adjustment means of the retaining element36can be augmented by an angle setting means.

The securing device31has a protective guard47that is detachably connected to the stepping element34and that, in the embodiment shown inFIG. 3A, is arranged on the side of the stepping element34associated with the hand-held power tool during the work. The protective guard47is connected to the stepping element34, for example, via a screwed connection and it can be screwed onto both sides of the stepping element34. Before using the securing device31, the user can adapt it to a left-handed or right-handed person.

FIGS. 4A, B show the securing device31in a side view during the processing of a first rectangular workpiece48having a first height H1and a first width B1(FIG. 4A) and of a second rectangular workpiece49having a second height H2and a second width B2(FIG. 4B). Here, the first workpiece48is higher than the second workpiece49(H1>H2), and the second workpiece49is wider than the first workpiece48(B1>B2).

The length of the support element35is set in such a way that the placement surface41of the stepping element34rests on the workpiece48,49, and the securing device31is supported on the substrate3via the support element35. The position of the retaining element36is set in such a way that the contact surface42rests on the workpiece48,49. Thanks to the retaining element36, the workpiece48,49that is to be secured is prevented from moving or slipping away under the stepping element34when the holding force is applied.

The securing device31is suitable for workpieces having a height of up to about 50 cm. Higher workpieces are not suitable for this securing technique since the height at which the stepping surface40is located does not allow the user to work ergonomically.

FIG. 5shows a third embodiment of a device51according to the invention for securing a workpiece52on the substrate3. In the case of heavy workpieces such as, for example, edge stones for curbs, there is very little risk that the workpiece52will slip away during the work since it is very heavy. In this case, there is no need to support and anchor the securing device51on the substrate3. The configuration of the support element of the securing device51differs from that of the securing device31.

The securing device51consists of the stepping element34, the retaining element36and another contact element53having another contact surface54. In order to be able to process workpieces of different widths, the retaining element36is configured so as to be adjustable.

The workpiece52is clamped between the contact surface42of the retaining element36and the contact surface54of the contact element53. Here, the term “clamped” means that there is as little leeway as possible between the contact surfaces42,54and the workpiece52. This arrangement prevents the securing device51from slipping away due to uncontrolled movements of the work tool relative to the workpiece52during the work.