IMPACT-DRIVEN KEY ARRANGEMENT

Abstract: A key arrangement (1) designed to turn a component forming part of a screwed joint, said arrangement exhibiting a sleeve (2) which is able to interact with a component, a rod-shaped organ (3) which is able to interact with the sleeve, a striking arm (4) which is able to rotate in conjunction with the organ and a handle (5) designed for a hand holding the key arrangement (1). The striking arm (4) consists of a main part (4a) and a mass concentration (4b) formed at one end or preferably at both ends, and with the main part (4a) attached to the rod-shaped organ (3) so that it is free to rotate in such a way that the striking arm can be turned between a number of stop positions (6′) so that, by coming to a halt in a particular stop position, it is able to transfer kinetic energy associated with the turning motion as shock torque to the rod-shaped organ (3) and to the component (2). At least one stop position is executed as a support (6′) arranged adjacent to the striking arm, securely connected to the rod-shaped organ and able to absorb impact forces from the striking arm, and with the rod-­ shaped organ (3) arranged in or adjacent to a centre line (5a) of the handle. The handle (5) and the rod-shaped organ (3) are connected together by the expedient of one of them ex­ hibiting a projecting pin (5b) and of the other exhibiting a recess (3b) corresponding to the pin, and with a part formed between the handle (5) and the organ (3) being so arranged as to serve as a bearing area for the striking arm (4) during its turning motion.

Description: TITLE OF THE INVENTION: KEY ARRANGEMENT DESIGNED TO TURN A COMPONENT FORMING PART OF A SCREWED JOINT Technical Field The present invention relates to a key arrangement and in particular to a key arrangement of a kind which is intended to turn a component forming part of a screwed joint. The key arrangement exhibits a sleeve, pin or similar capable of interacting with the component, a rod-shaped organ capable of interacting with the sleeve, a striking arm capable of rotating in conjunction with the organ and a handle designed for a hand holding the key arrangement. The striking arm consists of a main part and a mass concentration formed at one end or preferably at both ends, and the main part is attached to the rod-shaped organ so that it is free to rotate in such a way that the striking arm can be turned between a number of stop positions so that, by coming to a halt in a particular stop position, it is able to transfer kinetic energy associated with the turning motion as shock torque to the rod-shaped organ and the component. At least one stop position is executed as a support arranged adjacent to the striking arm, securely connected to the rod-shaped organ and able to absorb impact forces from the striking arm. The rod-shaped organ is also arranged on or adjacent to a centre line of the handle. Description of the prior art In Swedish Patent Application 8104104-8 is previously disclosed a key arrangement designed to turn a component forming part of a screwed joint, designated as an impact key, said key arrangement being intended to be capable of releasing and to a certain extent also of tightening the screwed joint, for which purpose it exhibits a main shaft, the end of which is provided with a means of contact such as washers or a flat steel plate attached by means of a strong bolted joint, or between which a so-called striking arm is mounted on a central guide, and whose function derives from the striking arm being caused to move in the desired direction of force, when its kinetic energy will be absorbed by end stops, impact bushes or similar so that the torque will be transmitted in the form of short but intensive torque pulses via a transmission tube to the sleeve which is used to release or to tighten one part of the screwed joint. As other examples of the prior art, reference may be made to the arrangement illustrated and described in American Patent Specification 2247521, and to the arrangements illustrated and described in German Patent Applications 1628012 and 2538473. Description of the present invention Technical problem Key arrangements of the aforementioned previously disclosed nature are already familiar in a large number of different embodiments, and a fundamental characteristic feature of the previously disclosed key arrangements is for an arm with mass concentrations at either end to be caused to rotate about a shaft, whereby the kinetic energy associated with the speed of rotation is allowed to be transmitted in the form of impact forces to a sleeve which interacts with one part of a screwed joint. With reference to previously disclosed designs, and in particular to the design which is illustrated and described in the aforementioned Swedish Patent Application 810410-8, it is clear that a major technical problem is encountered in conjunction with the design of a key arrangement of the aforementioned fundamental nature in which the component parts of the key arrangement are so dimensioned and executed that the key arrangement is easily operated, but in which the execution of said component parts is such that they may easily be brought into interaction with each other for the purpose of influencing the part of the screwed joint, in addition to which the component parts shall be capable, when not in use, of being combined together as a single unit for storage. Certain problems have also been encountered in conjunction with the dimensioning of the component parts of the key arrangement in such a way that the handle and the rod-shaped organ shall be capable of being connected to each other by the simple expedient of one of them exhibiting a pin and the other exhibiting a recess corresponding to the pin, and also by the part situated between the handle and the organ being so arranged as to serve as a bearing area for the impact arm during its turning motion. Certain problems have also been encountered in conjunction with the incorporation of measures in a key arrangement of the aforementioned nature such that the support may be executed in the form of legs formed on a 'U'-shaped component, said component being attached with advantage to the rod-shaped organ so that it is not free to rotate. Certain problems have also been encountered in conjunction with the creation of conditions for a key arrangement of the aforementioned nature such that the support could be executed in the form of a flat disc intended to absorb impact forces from one or more projecting parts formed on the striking arm. Previously disclosed designs have to an overwhelming extent been executed with fixed handles, and a major requirement exists, therefore, in the case of key arrangements of the aforementioned nature to create conditions such that the handle may be so arranged as to be capable of rotating in relation to the rod-shaped organ, said rod-shaped organ being executed for this purpose with a part about which the handle is so arranged as to be free to rotate. Solution The present invention relates to a key arrangement designed to turn a component forming part of a screwed joint and in particular to a key arrangement of a kind which is intended to exhibit a sleeve, pin or similar capable of interacting with the component, a rod-shaped organ capable of interacting with the sleeve, a striking arm capable of rotating in conjunction with the organ and a handle designed for a hand holding the key arrangement, said striking arm consisting of a main part and a mass concentration formed at one end or preferably at both ends, with the main part being attached to the rod-shaped organ so that it is free to rotate in such a way that the striking arm can be turned between a number of stop positions so that, by coming to a halt in a particular stop position, it is able to transfer kinetic energy associated with the turning motion as shock torque to the rod-shaped organ and the component, with at least one stop position being executed as a support arranged adjacent to the striking arm, securely connected to the rod-shaped organ and able to absorb impact forces from the striking arm, with the rod-shaped organ also being arranged on or adjacent to a centre line of the handle. The present invention proposes that the handle and the rod-shaped organ be connected to each other by the expedient of one of them exhibiting a pin and the other exhibiting a recess corresponding to the pin, and by the part situated between the handle and the organ being so arranged as to serve as a bearing area for the striking arm during its turning motion. The invention also proposes that the support may be executed in the form of legs formed on a 'U'-shaped component, and that said component shall be capable of being attached to the rod-shaped organ in such a way that it is not free to rotate. The support may also be executed in the form of a flat disc intended to absorb impact forces from one or more projecting parts formed on the striking arm. The handle should preferably be so arranged that it is free to rotate in relation to the rod-shaped organ, and the rod-shaped organ should preferably be so executed as to exhibit a part about which the handle is so arranged as to be free to rotate. The rod-shaped organ may also be so executed as to exhibit a tubular part into which a bar which is securely attached to the handle may be introduced. The invention also proposes the possibility of causing the sleeve, pin or similar to be attached to the rod-shaped organ in such a way that it is capable of being removed from it. Advantages The advantages which may principally be regarded as being characteristic of a key arrangement in accordance with the present invention designed to turn a component forming part of a screwed joint are that the key arrangement consists of a small number of component parts which are able easily to interact with each other so that they may be caused to interact with each other in order to influence the component parts of the screwed joint, but where said components are capable, when not in use, of being combined together into a compact unit for storage. The features which may principally be regarded as being characteristic of a key arrangement in accordance with the present invention designed to turn a component forming part of a screwed joint are indicated in the characterizing parts of the following Patent Claims. Description of the drawings A number of preferred embodiments exhibiting the significant characteristic features of the present invention are described below in greater detail with reference to the accompanying drawings, in which: Figure 1 shows a perspective view of a first embodiment of a key arrangement in which the constituent parts of the key arrangement are shown in exploded form; Figure 2 shows a section through a second embodiment; and Figure 3 shows a section through a third embodiment. Description of the preferred embodiments Figure 1 thus shows a perspective view of a key arrangement 1 designed to turn a component forming part of a screwed joint. The component part of the screwed joint is not shown in Figure 1, although said component part is intended to interact with a sleeve 2 , a pin or a similar organ. The key arrangement also exhibits a rod-shaped organ 3 capable of interacting with the sleeve 2 a striking arm 4 capable of rotating in conjunction with the organ 3 and a handle 5 designed for a hand holding the key arrangement 1 . The striking arm 4 consists of a main part 4a together with mass concentrations 4b executed at one end, or preferably at both ends in accordance with the embodiment shown in Figure 1. The main part 4a is attached by means of a hole 4c to the rod-shaped organ 3 in such a way as to be free to rotate so that the striking arm 4 can be turned between a number of stop positions so that, by coming to a halt in a particular stop position, it is able to transfer kinetic energy associated with the turning motion as shock torque to the rod-shaped organ 3 and to the component 2 . At least one stop position is executed as a support 6 arranged adjacent to the striking arm, securely connected to the rod-shaped organ 3 and able to absorb impact forces from the striking arm 4 . The centre line 3a of the rod-shaped organ 3 must also be arranged on or adjacent to a centre line Sa of the handle. In accordance with the present invention it is proposed that the handle 5 and the rod-shaped organ 3 be connected together by the expedient of one of them exhibiting a pin Sb and the other exhibiting a recess 3b corresponding to the pin. A part 6a formed between the handle 5 and the organ 3 shall also be so arranged as to serve as a bearing area for the striking arm 4 during its turning motion. The present invention proposes that the support 6 be executed from legs 6' formed on a 'U'-shaped component 6 . The component 6 is attached to the rod-shaped organ 3 in such a way as to be free to rotate via a welded joint not shown in the Figure. Figure 1 shows the handle 5 to have been executed with a pin 5b , whereas the rod-shaped organ 3 is shown to have been executed with a recess 3b , whereby the handle 5 and the rod-shaped organ can be brought into interaction with each other and whereby the pin Sb serves as a bearing surface for the arm 4 . It may be appropriate to provide a locking arrangement not shown in the Figure in order to lock the handle 5 in its engaged position with the rod-shaped organ 3 Figure 2 illustrates the manner in which a handle 5 has been formed with an internal recess Sc and in which the rod-shaped organ 3 has been formed with a pin 3b' , said pin being intended to interact with the recess Sc . In this case, too, it may be appropriate to provide a locking arrangement not shown in detail in the Figure between the pin 3b' and the recess Sc . Figure 2 also shows the manner in which the arm 4 is supported on the pin 3b' so as to be free to rotate and the manner in which the organ 6 has been executed with two legs 6' Figure 3 illustrates the manner in which the support 6 may be attached to the rod-shaped organ 3 in such a way that it is not free to rotate and may be executed in the form of a flat disc, said flat disc being designed to be capable of absorbing impact forces from one or more projecting parts 4d formed on the striking arm 4 It is also proposed in respect of all the preferred embodiments that the handle 5 be so arranged that it is free to rotate in relation to the rod-shaped organ 3 and the striking arm 4 , thereby enabling the striking arm 4 and the organ 3 to rotate without corresponding rotation of the handle 5 The rod-shaped organ 3 may also be executed with a part 3' to which or about which the handle 5 is so arranged that it is free to rotate. Figure 1 shows the rod-shaped organ 3 to have been executed with a tubular part 3' into which a bar 5b which is securely attached to the handle 5 may be introduced. The sleeve 2 or, in the event of the sleeve 2 having been replaced by a pin or similar, the latter may be attached in a previously disclosed manner to the rod-shaped organ in such a way that it is capable of being removed. It should, perhaps, be pointed out in conjunction with Figure 1 that the legs 6' have been executed at some-distance from the recess 3b so as to produce a practically acceptable design. Figure 2 shows more usual dimensioning of the support 6 in relation to the width of the arm 4 , from which it will be appreciated that the distance between the legs 6' should exceed the width of the arm 4 by a factor of between 1.5 and 4.0, although the most practical value is of the order of 3.0. In order to enable the components, when not in use, to be combined together as a single unit for storage, the present invention proposes that the length of the rod-shaped unit 3 together with the sleeve 2 and the support 6 be so dimensioned as to be less than the distance between the opposing surfaces of the mass concentrations 4b , and that the handle 5 and any bar Sb which may be attached to it be similarly dimensioned so as to be capable of being stored directly adjacent to the striking arm 4 between opposing end parts of the mass concentrations 4 b This will produce the advantage that the support 6 will lie next to one of the mass concentrations 4b whilst the sleeve 2 will lie next to the other mass concentration 4b The present invention is not, of course, restricted to the embodiment described above by way of example, but may be modified within the context of the following Patent Claims.

Claims: PATENT CLAIMS 1. A key arrangement designed to turn a component forming part of a screwed joint, exhibiting a sleeve, pin or similar capable of interacting with the component, a rod-shaped organ capable of interacting with the sleeve, a striking arm capable of rotating in conjunction with the organ and a handle designed for a hand holding the key arrangement, said striking arm consisting of a main part and a mass concentration formed at one end or preferably at both ends, and with the main part attached to the rod-shaped organ so that it is free to rotate in such a way that the striking arm can be turned between a number of stop positions so that, by coming to a halt in a particular stop position, it is able to transfer kinetic energy associated with the turning motion as shock torque to the rod-shaped organ and the component, whereby at least one stop position is executed as a support arranged adjacent to the striking arm, securely connected to the rod-shaped organ and able to absorb the impact forces from the striking arm, and with the rod-shaped organ arranged on or adjacent to a centre line of the handle, c h a r a c t e r i z e d in that the handle and the rod-shaped organ are connected together by one of them exhibiting a projecting pin and by the other exhibiting a recess corresponding to the pin, and in that a part formed between the handle and the organ is so arranged as to serve as a bearing area for the striking arm during its turning motion. 2. A key arrangement in accordance with Patent Claim 1, c h a r a c t e r i z e d in that the support consists of legs formed on a 'U'-shaped component. 3. A key arrangement in accordance with Patent Claim 2, c h a r a c t e r i z e d in that the component is secured to the rod-shaped organ in such a way that it is not free to rotate. 4. A key arrangement in accordance with Patent Claim 1, c h a r a c t e r i z e d in that the support is in the form of a flat disc intended to absorb impact forces from one or more projecting parts formed on the striking arm. 5. A key arrangement in accordance with Patent Claim 1, c h a r a c t e r i z e d in that the handle is able to rotate in relation to the rod-shaped organ. 6. A key arrangement in accordance with Patent Claim 1, c h a r a c t e r i z e d in that the rod-shaped organ is executed with a part about which the handle is free to rotate. 7. A key arrangement in accordance with Patent Claim 1, c h a r a c t e r i z e d in that the rod-shaped organ is executed with a tubular part into which a bar which is securely attached to the handle may be introduced. 8. A key arrangement in accordance with Patent Claim 1, c h a r a c t e r i z e d in that the sleeve, pin or similar is attached to the rod-shaped organ in such a way that it may be removed. 9. A key arrangement in accordance with Patent Claim 1, c ha r a c t e r i z e d i n that said handel (5) cooperates with said rod-shaped organ (3) by means of a locking device

Inventors: NASLUND, ROLF, Näslund, Rolf
Applicants: NASLUND, ROLF
Application year: 1984
Main classification: B25B19
IPC codes: B25B23, B25B19