MXPA99008667A - Motorization tool - Google Patents

Abstract

The present invention relates to a motorized tool for tightening and untightening a screw connected with a nut and a washer arranged so that the nut is stacked with one of its sides on one of the faces of the washer, the motorized tool comprising a housing, drive means adapted in the housing, and at least two coaxial connection means including a first connection means provided in the drive means for coupling and turning the nut and subjected to a turning force in one direction, and a second connection means provided in the housing and subjected to a turning force in an opposite direction, the coaxial connection means are formed such that the coaxial connecting means are being rotated while the other of the two coaxial connecting means they are at rest depending on a turning friction found as a result of one that connects to the washer while the other is connected With the nut, or as a result of one being connected to the screw and the other being connected to the nut, or as a result of one being connected to a reaction arm adapted to adjoin an adjacent stationary object while the other is connected to the nut , the second connection means includes two connection means, both provided in the housing axially spaced from one another and can be connected either with the washer, or with the screw, or with the reaction arm.

Description

MOTORIZED TOOL BACKGROUND OF THE INVENTION The present invention relates to motorized tools for tightening and untightening threaded connectors, such as screws provided with nuts and washers. It is known that most torque tools operated pneumatically, hydraulically, or manually have a smaller operating radius than the nut set for tightening. It is also known that the industry is trying to build smaller equipment despite higher pressures and higher loads. The Patent of E.U.A. No. 5,318,393, describes a nut that is composed of two sleeves that surround the screw. Its diameter can be reduced in relation to the nut it replaces. A tensioning screw described in my patent application of E.U.A. No. 09 / 033,790 filed on March 03, 1998, makes it possible to reduce the external diameter of the nut to below 1.5 times the diameter of the screw. This allows the manufacturer to place the screws closest to each other so that they obtain a better compression flow from the flange or housing. By placing the screws closest to each other, more, therefore smaller, screws can be applied to obtain the desired compression, especially since the pre-established desired residual load can be obtained very precisely.

To tighten a screw, a turning force is applied by means of a motorized tool and at the same time a reaction force must be applied which counteracts the force of rotation action. It is desirable to provide possibilities to apply the reaction force on various parts of the threaded fasteners, such as screws provided with nuts and washers. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a motorized tool that is a further improvement of existing motorized tools for tightening and unlocking bolts provided with washers and nuts. Keeping these objectives and others that will be more apparent hereafter, one aspect of the present invention resides, in short, in a motorized tool for tightening and untightening a screw having a nut and a washer arranged so that the screw is stacked with one of its sides on one of the faces of the washer, the motorized tool comprising the motorized tool A for tightening and untightening a screw connected with a nut and a washer arranged so that the screw is applied with one of its sides on a of the faces of the washer, the motorized tool comprising a housing, driving means adapted in the housing and at least two coaxial connecting means including a first connecting means provided for coupling and turning the nut and fastening to a turning force in one direction and a second connection means subject to a turning force in an opposite direction. The coaxial steering means being formed so that one coaxial connecting means rotates while the other of the two coaxial connecting means are at rest depending on a turning friction encountered as the result of which one is connected to the washer while the other is connected to the nut, or the result that one is connected to the screw and the other is connected to the nut, or as a result of which one is connected with a reaction arm adapted to abut against an adjacent stationary object while that the other is connected to the nut. When the power tool is designed in accordance with the present invention, when a threaded connector is tightened or untightened, an active turning force is applied to the screw nut, while a reaction force can be applied by the tool directly to the screw. screw so that the action force rotates around it, or it can be applied indirectly to the screw through the washer that connects to the screw so that the action force turns inward from the applied reaction force or the force of The reaction can be applied as a result of a connection to a reaction arm abutting against an adjacent stationary object. The novel aspects that are considered characteristic for the present invention are shown in particular in the appended claims. The invention itself however, both in terms of its construction and its method of operation, together with the additional objectives and advantages thereof, will be better understood from the following description of the specific modalities when read in relation to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS Figures 1 and 2 are views showing a lever-type motorized tool according to the present invention, which is provided for tightening or untightening a screw having a washer and a nut, with the application of a reaction force to the washer in Figure 1 and to the nut in Figure 2; Figures 3 and 4 are views showing a motorized rotary motor tool for tightening and untightening a screw provided with a washer and a nut, with the application of a reaction force to the washer in Figure 3 and to the screw in Figure 4; and Figure 5 is a view showing a motorized tool for tightening and untightening a screw, which is provided with a reaction arm adapted to abut against an adjacent stationary object to produce a reaction force. DESCRIPTION OF THE PREFERRED MODALITIES A motorized tool shown in Figure 1 is a lever-type power tool. It has drive means formed for example as a well-known hydraulic impeller which during a displacement of a piston in a hydraulic cylinder rotates a drive plate 2. which in turn rotates a ratchet 3 through a ratchet-ratchet mechanism. The tool also has a housing extending perpendicular to the axis of the drive unit 1 and a screw shaft. The housing is identified with reference to number 4 and adapts the hydraulic impeller 1 and the drive plate 2 with the ratchet 3. The motorized tool is used to tighten or untighten a threaded connector including a screw 5 extending through, for example, two parts P1 and P2. The screw 5 has a main portion 5 'extending through the parts P1 and P2, a threaded portion 5"and an intermediate portion 5'" which may have a polygonal outer surface. The threaded connector further has a polygonal washer which is identified by the reference numeral 6. The polygonal washer has a polygonal opening which fits over the polygonal portion 5 '"of the screw 5, and an external polygonal surface. a nut 7 which is formed as a conventional hexagonal nut having an internal threaded opening for screwing onto an external threaded surface of the portion 5"of the screw 5 and also having an external hexagonal surface. The motorized tool also has first connection means 8 for connecting the drive unit 1 with the nut 7. The first connection means 8 can be formed of a plurality of spindles provided on an inner surface of the ratchet 3 and coaxial with an axis of the screw 5. The first transmission means are provided to transmit a rotation of the ratchet 3 to the nut 7. The first transmission means include a crowned arrow 9 having a first portion 9 'provided with the plurality of spindles that engage the spindles of the first connecting means 8, and a second square portion 9"connected to a driving receptacle 10 The driving receiver 10 has a square opening with which it fits the square portion 9" of the arrow 9, and a portion tubular provided with an internal hexagonal opening with which the receptacle 10 can be adapted with the external hexagonal surface of the nut 7 motorized tool further has second connection means The second connection means include two selectively operable means One of the selectively operable means is identified with the reference number 11 and is formed for example by a plurality of internal spindles which are coaxial with the axis of the Screw The internal spindles 11 are located on one side of the housing according to an axial direction of the screw. In particular, as can be seen from Figures 1 and 2, the internal spindles 11 are located in the lower part of the housing 4 The second means of connection further include other selectively operable means which are identified with the reference number 12 and are formed for example by a plurality of internal spindles which are coaxial to the axis of the screw and are located on an opposite side of the housing as considered in the direction of the screw shaft or on top of the the housing The first connection means 8 and the second connection means 11, 12 are coaxial with each other. As can be seen in Figure 1, a transmission means formed as a reaction transmitter 13 non-rotatably connects the selectively operable means 11 to the washer 6. The transmission means is formed as a reaction receptacle having a portion 13 'provided with external spindles that engage with the internal spindles of the selectively operable means 11 and a portion 13"having a hexagonal internal surface adapted on the hexagonal external surface of the washer 6. As can be seen in Figure 2, another transmission member 14 non-rotatably connects the selectively operable means 12 to the screw 5. The transmission member 15 is formed as an arrow having a portion 14 'provided with external spindles which engage the internal spindles of the selectively operable means 12 and a portion 14"provided with external spindles and coupling with external spindles formed in an ab Extreme thickness of the screw 5. The lever-type motorized tool according to the present invention operates in the following manner: In the lever-type tool, such as, for example, a hydraulic jack, with the tool housing perpendicular to the axis of the lever. the drive unit and the screw shaft, the tool housing can not rotate around the screw without hitting obstacles on the application side Therefore, the tool housing remains stationary all the time When it is convenient to apply a force of active rotation to the nut 7 and apply a reaction force to the washer 6, the mode shown in Figure 1 is used The drive unit 1 is activated and rotated to the drive plate 2, the ratchet 3 is rotated by the drive plate 2 and through the first driving means 8 if the arrow 9 rotates so that the driving receptacle 10 is rotated and the nut 7 coupled to the receptacle The reaction receiver 13 is not rotatably connected to one side of the housing, in particular to the selectively operable means 11 of the second connection means on connection means on the one hand and is not rotatably connected to the washer 6 on the other side. the other side, the washer 6, in turn, is not rotatably connected with the screw 5 through the portion 5 '"As a result, a reaction force is applied to the screw, while the active force is applied to the nut , the nut is turned and the screw is pressed or relaxed in the parts P1 and P2, free of torsional load and lateral When it is necessary to apply a reaction force directly to the screw 6, the modality of Figure 2 is used Also here , the nut 7 is rotated by the driving receptacle 10 which is not rotatably connected to the first connecting means 8 provided in the ratchet 3 which are rotated in the driving plate 2 by the coupling. However, in contrast to the embodiments shown in Figure 2, the arrow 14 that is not rotatably connected to the selectively operable means 12 of the second connection means provided on the opposite side of the housing 4 are directly connected in a manner Therefore, during the operation of the tool only the nut rotates, but the screw does not rotate and, on the contrary, it is tightened or relaxed in the parts P1 and P2, free of torsional and lateral load. Figures 3 and 4 show a motorized tool of rotary motor type with a housing 24 having at least one part arranged coaxially with a drive shaft. The tool is also used to tighten or untighten a screw 5 having a washer 6 with an internal polygonal opening and an external polygonal surface and a normal hexagonal nut 7 with an internal thread and an external polygonal surface. The tool motorized is provided with first connecting means for connecting a drive unit not shown with the nut 7. The first connecting means are identified with the reference number 18 and are formed as a polygonal projection connected with a rotary arrow or the like of the drive unit not shown. A first transfer member 20 that is formed as a drive receptacle has a portion provided with an internal polygonal aperture coupled with the polygonal projection 18 and another portion provided with an internal hexagonal aperture that engages the hexagonal outer surface of the nut 7. .

The tool further has second connection means for non-rotatably connecting the housing 24 to the washer 6. The second connection means includes a selectively operable means which is formed, for example, as a polygonal projection 21 of the housing 24. The transmission medium non-rotatable is connected to the selectively operable means with the washer 6. It is formed as a reaction receptacle 23 having a portion provided with an internal polygonal aperture for coupling the polygonal projection 21 of the housing, and another portion provided with a polygonal aperture for attach an external polygonal surface of the washer 6, as shown in Figure 3.

The second connecting means of the power tool shown in Figures 3 and 4 also has other selectively operable means 22 which are formed, for example, as a non-rotating square projection connected to a non-rotating part of the housing or impeller. A transmission member 25 non-rotatably connects the selectively operable means 22 to the screw 5. The transmission member 25 has a portion 25 'which is provided with an internal square opening for receiving the square projection of the selectively operable means 22 and another portion polygonal 25"which engages not rotationally in a polygonal opening at one end of the screw 5. The motorized tool of the rotary motor type shown in Figures 3 and 4 operates as follows: When the drive unit of the tool is activated , rotates the polygonal projection 18 forming the first connection means and the receptacle 20, which in turn rotates the nut 7. In the situation shown in Figure 3, the reaction receptacle 23 non-rotatably connects the selectively operable means 21 with the washer 6, which in turn is connected non-rotatably with the screw 6, so that it provides a reaction force indirectly Through the washer 6. As a result, the nut 7 is rotated and the screw 5 is tensioned or relaxed in the torsion-free portions P1, P2 and lateral load. If it is convenient to react on the screw directly, the mode of Figure 4 is used. Here the driving receptacle 20 connects the first connecting means 18 with the nut 7, while the arrow 25 connects the selectively operable means 22 directly non-rotatably with the screw 5 to provide a reaction force. As a result, the nut 7 is rotated and the screw is tensioned or relaxed in the parts P1, P2, free of torsional and lateral load. Figure 5 shows a further embodiment of the tool according to the present invention. The tool here is provided with a reaction arm 33. The reaction arm 33 has a portion 333 'which connects non-rotatably, for example with selectively operable means 11 of the second connection means. In addition it has another portion 33"which is adapted to abut against a stationary adjacent object.The motorized tool shown in Figure 5 operates in the following manner.

The drive unit 1 is activated and rotates the drive plate 2, the ratchet 3 is rotated by the drive plate 2 and through the first connecting means 8 rotate the arrow 9 so that the driving receptacle 10 is rotated, and the nut 7 engaged by the drive receptacle is rotated. The reaction arm 33 abuts against an adjacent stationary object, for example against a surrounding nut or the screw. As a result, the reaction force is applied to the tool housing, while the active force is applied to the nut, the nut is turned and then the but is not tensioned or relaxed in parts P1 and P2, free of charge of torsion and lateral. It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of constructions that differ from the types described above. While the invention has been illustrated and described as being modalized in a motorized toolthey are not intended to be limited to the details shown, since various modifications and structural changes can be made without departing in any way from the spirit of the present invention. Without further analysis, the following will fully reveal the essence of the present invention than others, applying current knowledge. they can easily adapt for various applications without omitting aspects which, from the point of view of the prior art, constitute the essential characteristics of the generic or specific aspects of this invention.

Claims (7)

1. CLAIMS 1. A motorized tool to tighten and untighten a screw connected with a nut and a washer arranged so that the nut is stacked with one of its sides on one of the faces of the washer, the motorized tool comprising a housing; drive means adapted in the housing; and at least two coaxial connecting means including a first connecting means provided for coupling and turning the nut and subjected to a turning force in one direction and a second connecting means subjected to a turning force in an opposite direction, the coaxial connecting means being formed such that one of the coaxial connecting means is rotated while the other of the two coaxial connecting means is at rest depending on a turning friction encountered as a result of one connecting with the washer while that the other is connected to the nut, or the result that one is connected to the screw and the other is connected to the nut, or as a result of which one is connected with a reaction arm adapted to adjoin an adjacent stationary object while the other connects with the nut.
2. 2. A motorized tool according to claim 1, wherein the second connection means includes two selectively operable means that are axially spaced from each other.
3. 3. A motorized tool according to claim 2, wherein the driving means and the housing are arranged so as to together form a lever-type motorized tool with the housing extended perpendicular to a driving axis of the driving means, the two selectively operable means of the second connection means being arranged on opposite sides of the housing considered in a direction of an axis of the coaxial connecting means. A motorized tool according to claim 2, wherein the drive means and the housing are arranged so as to form a motorized tool of rotary motor type with the housing arranged coaxially with a drive shaft of the drive means , two selectively operable means of the second connection means being arranged on one side of the housing as it is considered in a direction of an axis of the coaxial connection means. 5. A motorized tool according to claim 2; and further comprising transmission means for transmitting a force of a respective one of the connecting means to a respective one of the screw, the nut and the washer. 6. A motorized tool according to claim 5. wherein the transmission means includes a first transmission means for connecting the first connection means with the nut and formed as a drive receptacle that rotatably connects the drive means through of the first transmission means with the nut, a second transmission means for non-rotatably connecting one of the selectively non-operable means of the second connection means to the washer and formed as a reaction receptacle that holds the washer non-rotatably in relation to the housing and a third transmission means for non-rotatably connecting another of the selectively operable means of the second transmission means with the screw formed as a projection that hold the screw non-rotatably in relation to the housing. A motorized tool according to claim 2, wherein at least one of the selectively operable means of the second connection means is connected to the reaction arm adapted to abut against an adjacent stationary object.