AN IMPULSE TORQUE TOOL FOR A COMPONENT OF A BOLTED JOINT

Abstract: An impulse torque tool for loosening and/or tightening a component forming part of a bolted joint and of the type incorporating a holder part (2) and a base part (4) cooperating therewith and having a socket (15) for a dowel or bushing and where an impact arm (3) is arranged between holder part and base part and adapted during rotation about the longitudinal axis of the torque tool to transfer impact torsional forces to an impact member (16) projecting radially from the impulse torque tool, wherein the holder consists of a cylinder (5) having an annular groove (6) and a concentric, threaded dowel (7) projecting from one end face of the cylinder and being adapted to be screwed into a corresponding bore (14) of the base portion, and by an external tubular sleeve (9) intended to be slid over the cylinder and to be attached to this by means of an impression (11) of the wall material of the tubular sleeve into the groove in the cylinder in such a manner that the tubular sleeve is rotatably fitted to the cylinder (5) but axially arrested thereto.

Description: AN IMPULSE TORQUE TOOL FOR A COMPONENT OF A BOLTED JOINT Background of the invention The invention refers to an impulse torque tool intended for loosening and/or tightening a component forming part of a bolted joint and of the type incorpora ing a holder part and a base part cooperating therewith and having a socket for a dowel or bushing and where an impact arm is arranged between. holder part and base part and, adapted during rotation about the longitudinal axis of the torque tool to transfer impact torsional forces to an impact member projecting radially from the impulse torque tool. Impulse torque tools of this type are earlier known in different embodiments, and their purpose is mainly to give a possibility also for persons lacking big body forces to untighten heavily- tightened bolts and even bolts that have been stuck with rust. Earlier known embodiments have- suffered from drawbacks, which e.g. have consisted in that the holder and base portions of the tool have been loosely fitted into each other with the risk that the parts will fall apart at use. Earlier known impulse torque tools have furthermore been heavy, which gives drawbacks from weight and cost aspects as well as regarding their use. Purpose and most important features of the invention The purpose of the present invention is to provide an impulse torque tool, which eliminates the above mentioned drawbacks and this has been achived at a impulse torque tool of the type defined hereabove, thereby that the holder consists of a cylinder having an annular groove and a concentric, threaded dowel projecting from one end face of the cylinder and being adapted to be screwed into a corresponding bore in the base portion, and by an external tubular sleeve intended to be slid over the cylinder and to be attached to this by means of an impression of the wall material of the tubular sleeve into the groove in the cylinder in such a manner that the tubular .Si sleeve is rotatably fitted to the cylinder but axially arrested thereto. Further characteristics and features of the invention are presented in the subclaims. Description of the drawings The inveτrt"ix>π will hereinafter be further described with references ro: an embodiment shown in the accompanying drawing. Figure 1 shows an impulse torque tool according to the invention in a side elevation partly in cross section. Figure 2 is a view in bigger scale of a holder part forming part of the impulse torque tool according to the invention. Figure 3 shows a planar view of the impact arm, and Figure 4 shows in bigger scale and partly in cross section a base portion forming part of the impulse torque tool according to Figure 1. PesςriPtion of the preferre . embodiment In figure 1 is shown in a side elevation and partly in cross section an impulse torque tool 1 according to the invention, which incorporates a holder part 2, an impact arm 3 and a base part 4, which are interconnected in such a manner, that the holder part and the base part together constitute an elongated shaft about which the impact arm is rotatable. The holder part 2 incorporates a cylinder 5, which is further shown in bigger scale in figure 2 and which is equipped with an annular groove 6. At one of its ends the cylinder terminates in a concentric dowel 7, which is provided with a thread. In the area between the cylinder and the dowel there is nonrotatably arranged a preferably two-armed wing 8. The holder part furthermore incorporates a tubular sleeve 9 , which is slid over the cylinder, which as shown in figure 1 , projects outside the cylinder and in this particular embodiment externally is provided with a grip-promoting material 10, e.g. rubber or plastic material. This outer tubular sleeve-shaped holder part 9 is attached to the cylinder thus that it is rotatable relative to the cylinder, but axially arrested relative thereto, by the material in the tubular sleeve being impressed 11 in the groove 6 of the cylinder 5. The impact arm 3 is shown in bigger scale and in a view from above in figure 3, and as can be seen it consists of an elongated arm, which at its center is provided with a bore 12 and at each end carries a weight 13. As seen in figure 3, the design is such that impact will occur against the short side of the arm material, which in turn eliminates any friction in the arm at the moment of impact. Figure 4 shows in a side view and partly in cross section the base part 4, which consists of a bar, which at its lower end is equipped with a socket 14 for any arbitrary bolt bushing or the like, and it has at its upper end a concentrically located, threaded blind hole 15, and a radially projecting wing 16 fixedly attached to the bar. By the design of the holder part a reliable connection will be obtained between holder part and base part without the movability or the ability of handle rotation thereby being lost. Upon manufacture the components may thus be delivered with the internal cylinder and the external tubular sleeve of the holder part interconnected by means of an impression 11 , which engages into the groove 6 of the cylinder, and at assembly of the tool of the wing 8, which is fixedly attached to the cylinder, is used as a handle. This wing has a further function as a fender means during use of the impulse torque tool, in order to ascertain that the hands of the operator will not slide from the holder and into the working area of the impact arm. Due to the design of the impact member for the impact arm shown n the figures as a wing 16 extending in one direction only, in contrast to earlier multi-armed impact surfaces it is also gained a lower tool weight, altough the design will not lead to unsymmetrical loads on the base part. It is further gained that the impact against this single impact member will be more distinct than when two or more impact members are used, as the play, swaying and balanzing forces, which are inevitable at simultaneous impact against several shoulders, are ttrere y eliminated. The impact will thus be more momentaneous than what can be achieved with earlier impact member designs and the impul .e torque tool according to the invention therefore implies that the losses in force transfer will be very low. The invention is not limited to the embodiment shown in the drawing and described in connection thereto but variations and modifications are possible within the scope of the appended claims .

Claims: CLAIMS 1. An impulse torque tool for loosening and/or tightening a component forming part of a bolted ^oint and of the type incorporating a holder part (2) and a base part (4) cooperating therewith and having a socket (15) for a dowel or bushing and where an impact arm (3) is arranged between holder part and base part and adapted during rotation about the longitudinal axis of the .torque tool to transfer impact torsional forces to an impact member (16) projecting radially from the impulse torque tool, c h a r a c t e r i z e d t h e r e b y, that the holder consists of a cylinder (5) having an annular groove (6) and a concentric, threaded dowel (7) projecting from one end face of the cylinder and being adapted to be screwed into a corresponding bore (14) in the base portion, and by an external tubular sleeve (9) intended to be slid over the cylinder and to be attached to this by means of an impression (11 ) of the wall material of the tubular sleeve into the groove of the cylinder in such a manner that the tubular sleeve is rotatably fitted to the cylinder (5) but axially arrested thereto. 2. An impulse torque tool according to claim 1 , c h a r a c t e r i z e d t h e r e b y, that the cylinder (5) of the holder part is equipped with a double-sided radial w ng (θ) which is nonrotatably fitted at the junction between cylinder (5) and dowel (7) for making possible the screwing in of the holder part (2) into the base part (4) and protecting the hands of the operator from the motion path of the impact arm (3) . 3. An impulse torque tool according to anyone of the preceeding claims , c h a a c t e r i z e d t h e r e b y, that the impact arm (3) is intended to transfer torque to the shaft formed by the holder part (2) and the base part (4) via impact against a single wing (16) which is nonrotatably fitted to the shaft and projects radially therefrom and has a flange part bent at' an angle thereto.

Inventors: ANDERSSON STEN-AOKE, ANDERSSON, STEN-AOKE
Applicants: ANDERSSON STEN AKE, ANDERSSON, STEN-AOKE
Application year: 1986
Main classification: B25B19
IPC codes: B25B19