WO2007057022A1

WO2007057022A1 - A tool for pulling or lifting an object

Info

Publication number: WO2007057022A1
Application number: PCT/DK2006/000644
Authority: WO
Inventors: Egon Henneberg
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-11-21
Filing date: 2006-11-20
Publication date: 2007-05-24
Anticipated expiration: 2008-05-21
Also published as: DK200501628A; DK176360B1

Abstract

The invention relates to a tool for pulling or lifting an object in a pull direction. The tool comprises a pull device comprising at least two parts that can be displaced relatively in relation to each other in the pull direction. The one part (101) of the pull device is connected via inclined guides (111) to at least two gripper devices (108), each of which has at least one gripper face (116), between which gripper faces the object is arranged. The other part of the pull device (102) is connected to a stop means (105) to which at least the movement in the pull direction of the gripper means is partially controlled, to the effect that a portion of a pull force in the pull direction of the tool will displace the two parts of the pull device relative to each other (104, 107), whereby, due to the inclined guides, the gripper devices will be forced at least partially in a direction (113) towards each other and hence squeeze around the object in a direction approximately perpendicular to the pull direction. Hereby the advantageous feature is accomplished that it is possible to hold on to an object while simultaneously a pull is exerted in the object; and that a portion of the pull force is used to hold on to the object.

Description

A tool for pulling or lifting an object

The invention relates to a tool for pulling or lifting an object in a pull direction.

Background

In the field of business of electricians, it is often necessary to convey wires from one area to another area. This is typically from a current distributor to a wall socket where the current distributor in a house receives the current from the electricity works to subsequently distribute the current to the various rooms in the house. Wires are also to be taken between two wall sockets. This is done by protective tubes being inserted into the walls of the house between the wall sockets and the power distributor. The protective tubes are often laid into the walls between a number of different rooms in the house, and they will therefore often have bends in order to convey the wires ia around corners or to avoid other installations, such as water piping, other wires or armouring in the wall which are also laid into the walls of the housing.

Therefore the electrician is able to pull the wires through the protective pipes and on to the wall sockets when the house is built. In order to facilitate the work of pulling the wires through the pipe, a search spring is first taken through the pipe. The search spring is a long piece of nylon with an elongate spring at the end and, due to the spring, it is easily taken through a protective tube which is often bent. When the search spring has been taken through the protective pipe, the wires are secured to the one end of the search spring, and the search spring is subsequently pulled out of the protective tube. The wires will follow the search spring out of the tube and are hence pulled through the protective tube. However, it is often difficult for the electrician to pull the search spring and the wires through the protective tube due to the large frictional resistance between the wires and the protective tube. The problem increases with the number of wires to be pulled through the tube and with the number of bends on the tube. Therefore the electrician has to use much force to pull the wires through the tube.

Moreover the electrician may experience problems holding properly on to the search spring due to it being thin and long and therefore easily slipping from his hands when seized while simultaneously exerting much force to pull. Often the electrician attempts to improve his grip on the search spring by winding it one or more times around his hand, whereby the spring is tightened around the hand when the spring is pulled. However, this means that the spring may cut into the electrician's hand with an ensuing work- related injury due to it being elongate and thin and thus possibly acting like a knife.

The electrician may also use nippers to improve his grip around the search spring, but experience has shown that nippers often cut over the search spring with the result that the search spring cannot be used again.

Finally it is an option for the electrician to use flat pliers or drawing pliers with rubber coating. It is common to both types of pliers that the electrician has a poor hand position relative to his direction of pull, and that simultaneously much force has to be exerted to seize around the search spring due to the pliers being based on the sax principle.

The problems of pulling and lifting an object are also encountered when large cables for the power supply are to be drawn or when a steel wire has to be moved in the context of eg construction work. Object and description of the invention

The object of the invention is to provide a tool and a method by which the problems described above are remedied; to be able to seize around an object while simultaneously pulling the object without losing one's grip around the object.

This is solved in accordance with the invention by means of a tool comprising a pull device comprising at least two parts that can be displaced relative to each other in the pull direction. The one end of the pull device is connected via inclined guides to at least two gripper devices having each at least one gripper face between which gripper faces the object is arranged. The other part of the pull device is connected to a stop means to which at least the movement of the gripper device in the pull direction is partially guided, whereby a portion of a pull force exerted in the pull direction in the tool will displace the two parts of the pull device relative to each other, whereby - due to the inclined guides - the gripper devices will be forced at least partially in a direction towards each other and thereby squeeze around the object in a direction approximately perpendicular to the pull direction. Hereby the advantageous aspect is obtained that it is possible to hold on to an object simultaneously with the object being pulled in, and that a portion of the pull force is used for holding on to the object. This is accomplished because the two parts of the pull device are displaced relatively in relation to each other in the pull direction which also presents the advantage that a sensible grip in the pull device can be obtained during the pull, meaning that extra forces are not needed for seizing around the object. Moreover some of the resistance arising when an object is to be pulled or lifted will also be translated into a gripping force securing the object which in turn means that there is no need for additional forces for securing the object. In total this means that the grip around the object is tightened the harder the pull in the object. According to one embodiment of a tool for pulling or lifting an object in a pull direction as described above, the gripping faces of the gripper device have a coarse surface or are coated with rubber. The result is an improved grip in the object due to the frictional forces between the gripper devices and the object being increased, and hence it is possible to pull harder in the object without the object being lost.

According to one embodiment of a tool for pulling or lifting an object in a pull direction as described above, the gripper faces of the gripper devices are approximately in parallel. This means that the gripper faces are able to contribute with a uniform pressure throughout a large face on the object, meaning that the risk of the tool cutting the object is minimised.

According to one embodiment of a tool for pulling or lifting an object in a pull direction as described above, a spring is provided in connection with the stop means, whereby the gripper device does not grip in its resting position. Hereby the advantage is obtained that forces are not needed for opening the gripper device when a new object is to be seized or when the object is let go.

According to an embodiment of a tool for pulling or lifting an object in a pull direction as described above, a spring is mounted in connection with the stop means, whereby the gripper device grips automatically in its resting position. Hereby the advantage is obtained that the tool is able to grip around an object without a pull being necessarily exerted in the tool. This may be desirable when it is desired to interrupt the pull without the grip around the object being lost.

According to one embodiment of a tool for pulling or lifting an object in a pull direction as described above, the tool is configured as a hand-held tool and the pull device constitutes a handle. This means that the tool can easily be used by a workman who wishes to lift or pull an object. The workman accomplishes the advantage that he or she is able to lift the object without having to also use forces on seizing around the object. Simultaneously the workman obtains an advantageous grip in the handle for a pull to be performed. The workman may be eg an electrician who is to pull a search spring with wires through a protective tube.

One method of securing and simultaneously pulling or lifting an object in a pull direction is by applying a pull force onto the object in the pull direction. The method comprises a pull device comprising at least two parts that are displaced relative to each other in the pull direction. The one part of the pull device is connected via inclined guides to at least two gripping devices, each of which has at least one gripper face, between which gripper faces the object is arranged. The second part of the pull device is connected to a stop means towards which at least the movement of the gripper device is guided, whereby a portion of a pull force in the pull direction displaces the two parts of the pull device relative to each other, whereby the gripper devices are forced in a direction towards each other, due to the inclined guides, and hence squeeze around the object in a direction approximately perpendicular to the pull direction. Hereby the advantageous aspect is accomplished that it is possible to hold on to an object, while simultaneously a pull is exerted in the tool; and that a portion of the pull force is used to hold on to the object. This is accomplished because the two parts of the pull device are displaced relatively in relation to each other in the pull direction, which also provides the advantage that a sensible grip in the pull device can be obtained during the pull, meaning that no extra forces are required for seizing around the object. Additionally, a part of the resistance occurring when an object is to be pulled or lifted will also be converted into a gripping force securing the object, which in turn means that no extra forces are required for seizing around the object. Overall, this means that the pull around the object is tightened as the pull in the object becomes increasingly harder. Brief description of drawing

In the following the invention is described with reference to the figures, wherein

Figure 1a shows an embodiment of the invention, seen from above;

Figure 1 b shows an embodiment of the invention, seen from the side;

Figure 1 c shows an embodiment of the invention, seen from the front;

Figure 2 shows a cross-sectional view taken along A-A in Figure 1 b of an embodiment in which the gripper device is not activated;

Figure 3 shows a cross-sectional view taken along A-A in Figure 1 b of an embodiment in which the gripper device is activated;

Figure 4 shows an embodiment, where only the one gripper device is displaced in a scenario where the gripper device is not activated;

Figure 5 shows an embodiment in which only the one gripper device is displaced in a scenario where the gripper device is activated;

Figure 6 shows an embodiment with a spring mounted which makes the gripper devices slide apart;

Figure 7 shows an embodiment with a spring mounted that makes the gripper devices slide towards each other;

Figure 8 shows two gripper devices with through-going inclined guides and with a gripper face coated with rubber; Figure 9 shows a gripper device configured with pins or grooves.

Description of embodiments

Figure 1 shows an embodiment of the invention seen from above (Figure 1a), from the side (Figure 1 b) and from the front (Figure 1c). The invention consists of a pull device having a first part (101) and a second part (102). The first part (101 ) of the pull device is secured to a housing (103) and used for pulling or lifting by transferring a pull force (104) to the first part of the pull device. The second part (102) of the pull device is in connection with a stop means (105) via a rod (106) which is taken through the housing and the first part of the pull device via a hole. Via a pressing force (107) the second part of the pull device is pressed towards the first part of the pull device, and simultaneously the stop means (105) will be pushed towards two gripper devices (108) that are enclosed by the housing. The housing is provided with an aperture (109) into which the object (not shown) which is to be pulled or lifted can be introduced. This housing is designed for pulling or lifting a relatively long and thin object, but it may be configured for seizing around the object with another shape. The gripper device (108) is secured within the housing via support bars (110) that are secured to the upper face and lower face of the housing. The support bars are taken through two inclined guides on the gripper device. The inclined guides (111) are inclined relative to the pull device in such a manner that they simultaneously cause the gripper devices to be brought together when the gripper device is pushed.

Figure 2 is a cross-sectional view of a preferred embodiment of the invention taken along A-A in figure 1c. The Figure shows the embodiment in a situation, where the second part (102) of the pull device is not displaced towards the first part (101) of the pull device. The two gripper devices (108) have inclined guides (111) configured as an elongate aperture and inclined relative to the pull direction in such a manner that they cause the gripper devices to move towards each other when the gripper device is pushed. This is accomplished by the inclined guides being configured mirror-inverted on the two gripper devices. Through the inclined guides, support bars (110) are conveyed which are secured to the tool housing. The gripper devices are secured only via the inclined guides (111 ) and the support bars (110) and therefore they can be moved in the directions allowed by the inclined guides.

Figure 3 is a cross-sectional view of the same embodiment as Figure 2, but herein the second part (102) of the pull device is pushed towards the first part (101 ) of the pull device, and the gripper devices seize around the object. When the second part of the pull device is pressed towards the first part of the pull device, the stop means (105) will push the gripper devices (108) which will shift towards each other due to the inclined guides (111) causing the gripper devices to be forced towards each other when pushed by the stop means. The arrow (112) shows the direction of movement of the stop means, and arrows (113) show the movement direction of the gripper device. In this embodiment each gripper device has two identical inclined guides, causing the two gripper devices to be brought together in parallel whereby the gripper faces of the gripper device acts on a large area. This means that the gripper faces are able to hold on to an elongate, thin object without the object being cut. The gripper devices can also be configured with one or more guides, and the embodiment depends on how the gripper devices are to seize around the object. Additionally, the tool can be configured with several gripper devices, eg in case it is desirable to be able to seize around several objects at a time or be able to seize in different places on the object.

Figure 4 is a cross-sectional view of an embodiment of the invention which, as opposed to the embodiment shown in figures 2 and 3, has only one movable gripper device (108). The figure shows the embodiment in a situation where the gripper devices are not activated. The second gripper device (114) is constituted by a stationary face in the tool. The advantage of this embodiment is that it is narrower than the embodiment shown in figures 2 and 3 and has only one movable part. It also has an asymmetrical pressure in its grip around the object which is conceivably advantageous in situations when the object is to be pulled in a diagonal direction.

Figure 5 shows the same embodiment as Figure 4, but herein the gripper device is activated and the object is seized. During the activation the gripper device will move as shown by arrow (115).

Figure 6 shows the same embodiment as figures 2 and 3, but here a spring (116) is mounted that automatically presses apart the first part and the second part of the pull device, whereby the stop means (105) is caused to pull in the gripper devices via two hinges (117). This means that the gripping faces of the gripper devices slide apart, when the tool is not used. It means that the tool will automatically let go of the object when the object is not pulled. The spring causes the second part of the pull device to move in the direction of the arrow (118), with the result that the gripper devices move in the direction indicated by arrows (119).

Figure 7 shows the same embodiment as figures 2 and 3, but here a spring (120) is mounted between the stop means (105) and the housing (103). The spring makes the stop means push the gripper devices to the effect that the gripper faces of the gripper devices are automatically brought together when the tool is not in use. This means that the gripper faces of the gripper devices hold on to the object, also in case a pull is not exerted in the pull device. The spring (120) causes the stop means to move in the direction of the arrow (121 ), meaning that the gripper devices move in the direction indicated by arrows (122). In Figure 8 a set of gripper devices is shown where the inclined guides (110) are configured as through-going holes in the gripper devices. Moreover the gripper faces (123) of the gripper device are coarse or coated with a rubber coating, meaning that an improved grip around the object is accomplished. The inclined guides can also be configured as an indentation in the gripper device, and instead of the through-going support bars pins/grooves can be used that engage the guides and sit securely on the housing. The guides can be configured in may ways, but all embodiments share the feature that they are to be able to convey the gripper devices towards each other, when a force is applied to the gripper devices. It may be eg elongate guides or circular guides.

Figure 9 shows a gripper device wherein one or more pins/grooves (124) are mounted instead of the inclined guides. The pins are to be inserted in inclined guides that are eg cut into a surrounding housing. Thereby the same effect is obtained as is obtained when the gripper devices are configured with inclined guides.

The invention may be made of many different materials, eg plastics, iron, stainless steel, wood, or combinations of the above. The individual parts of the invention can be manufactured via a moulding process or by a workmanlike processing of the materials.

Claims

C l a i m s

1. A tool for pulling or lifting an object in a pull direction, which tool comprises a pull device comprising at least two parts (101 , 102) that can be displaced relatively in relation to each other in the pull direction (104); and at least two gripper devices (108), each of which has at least one gripper face (123), said tool being characterised in that the one part (101 ) of the pull device is connected via inclined guides (111 ) to at least one of the gripper devices (108); and wherein the second part (102) of the pull device is connected to a stop means (105) for which the movement of at least on of the gripper devices in the pull direction is partially controlled, whereby a portion of a pull force in the pull direction on the tool will displace the two parts of the pull device relative to each other, whereby at least one of said gripper devices will, due to the inclined guides, be forced at least partially in a direction (113, 115) towards at least one other gripper device, whereby the gripper devices will squeeze around one or more objects, if any, situated between the gripper faces in a direction approximately perpendicular to the pull direction (104).

2. A tool for pulling or lifting an object in a pull direction according to claim 1 , characterised in that the gripper faces of the gripper device has a coarse surface.

3. A tool for pulling or lifting an object in a pull direction according to claim 1 or claim 2, characterised in that the gripper faces of the gripper devices are coated with rubber.

4. A tool for pulling or lifting an object in a pull direction according to one or more of claims 1-3, characterised in that the gripper faces of the gripper devices are approximately in parallel.

5. A tool for pulling or lifting an object in a pull direction according to one or more of claims 1-4, characterised in that said tool is configured as a handheld tool, wherein the pull device constitutes a handle.

6. A method of holding on to and simultaneously pulling or lifting an object in a pull direction by applying to the object a pull force in the pull direction, said method comprising a pull device comprising at least two parts (101 , 102) which are displaced relatively in relation to each other in the pull direction (104), said method further comprising at least two gripper devices (108), each of which comprises at least one gripper face (123), characterised in that the one part of the gripper device is connected via inclined guides (111 ) to at least one of said gripper devices (108), and wherein the second part of the gripper device is connected to a stop means to which the movement of at least one of said gripper devices in the pull direction is controlled to the effect that a portion of a pull force in the pull direction displaces the two parts of the pull device relative to each other, whereby at least one of said gripper devices will, due to the inclined guides, be forced at least partially in a direction (113, 115) towards at least one other gripper device, and whereby the gripper devices will squeeze around one or more objects, if any, situated between the gripper faces in a direction approximately perpendicular to the pull direction (104).