HAND GRIP FOR A WASHING GUN

Abstract: The invention relates to a washing gun with improved ergonometric characteristics, which washing gun basically comprises a nozzle section (8), a hand grip section (9, 9', 9'') and a trigger (6) where the hand grip section (9) is placed such relative to the nozzle section (8) that the distance between the longitudinal axis (2) through the nozzle section (8) and the longitudinal axis (4) through the forearm of the operator is essentially zero or at least significantly reduced compared to prior art washing guns, such that the torque due to the reaction force exerted on the wrist of the operator is significantly reduced, leading to less fatigue during operation of the washing gun. Furthermore the trigger (6) is positioned in such a manner, that the reaction force from the jet of fluid leaving the nozzle (8) helps to maintain said trigger (6) in an activated position during use of the washing gun.

Description: HAND GRIP FOR A WASHING GUN TECHNICAL FIELD The present invention relates to washing guns used in connection with cleaning, distribution of cleansing agents etc. in industry and more particularly to the design and functioning of a hand grip to be used in such guns as set forth in the preamble of claim 1. DESCRIPTION OF PRIOR ART A typical washing gun comprises an inlet for the washing fluid, such as for instance water, communicating via suitable intermediary means with a fluid outlet in the form of a nozzle section and a hand grip section somehow provided with a trigger. Usually the hand grip and the trigger is positioned off the longitudinal axis through the nozzle section so that during operation of the washer, the reaction force on the washer caused by the jet of fluid leaving the nozzle produces a torque, which tends to twist the wrist and forearm of the operator during use of the washer, which is undesired from an ergo- nomic point of view as it leads to stress and fatigue of the muscles of the wrist and arm of the operator. A prior art washing gun with the characteristics mentioned above is for instance disclosed in U.S. patent no. 6,000,637, entitled "High pressure water gun". Furthermore, if the trigger is not provided with a retainer mechanism, which when desired locks the trigger in the activated position, it is necessary for the operator during use of the washing gun constantly to press the trigger towards the handle portion leading to fatigue of the finger muscles of the operator. Keeping the washer in an open position by means of a retainer mechanism is however not a proper solution for safety reasons, because if the user during a cleaning operation incidentally drops the washing gun, the jet of fluid from the washing gun may cause severe damage, particularly when a high pressure washer is concerned. SUMMARY OF THE INVENTION It is the object of the present invention to provide a washing gun which does not give rise to or at least minimises the above-mentioned ergonomic problems resulting partly from said torque produced by the reaction force on the nozzle portion and partly from the necessity to exert a constant activation force on the trigger during operation of the washing gun. More specifically it is thus a first object of the present invention to provide a washing gun which during use hereof does not give rise to or at least minimises said torque produced by the reaction force from the jet of washing fluid leaving the nozzle. It is a second object of the present invention to provide a washing gun where said reaction force on the nozzle facilitates the required activation of the trigger hence reduc- ing the muscle force required from the fingers of the operator during use of the washing gun. The above objects are attained with a washing gun according to the present invention where the distance between the longitudinal axis through the nozzle section of the washing gun and the longitudinal axis through the forearm of the operator during operation of the washing gun is either substantially zero or at least significantly reduced compared to prior art washing guns. According to the present invention, the hand grip section extends on either side of a plane containing the longitudinal axis of said nozzle section, so that some of the operators fingers during operation of the washing gun can be placed on one side of said plane, whereas others of the fingers of the operator can be placed on the other side of said plane. According to one embodiment of the washing gun, said longitudinal axis through the nozzle section of the washing gun during operation substantially coincides with the longitudinal axis through the forearm of the operator, when the operator during use of the washing gun grips around said hand grip section, thus essentially reducing the torque produced by the reaction force from the washing fluid leaving the nozzle to zero. Furthermore, the trigger of the washing gun according to the invention is located such that said reaction force from the jet of fluid during operation of the washing gun contributes to the total force necessary to effect a relative displacement between the trigger and the main body of the washing gun, which relative displacement is necessary in order to activate the trigger and to keep this in an activated state during operation of the washing gun. BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described in more detail with reference to the accompanying drawings, in which figure 1 is an embodiment of a prior art washing gun; figure 2 is a first embodiment of a washing gun according to the invention; and figure 3 is a second embodiment of a washing gun according to the invention. DETAILED DESCRIPTION OF THE INVENTION In the following a detailed description of two specific embodiments of the invention are described. Referring to figure 1 , there is shown a prior art washing gun, generally designated by 1 and provided with a trigger 3 to be activated by the operator during use of the washing gun. The prior art washing gun is characterised in that the longitudinal axis 2 through the jet and nozzle part of the washing gun does not coincide with the longitudinal axis 4 through the forearm of the operator, but is displaced a distance X from the axis 4. Thus, the reaction force F of the jet during operation of the washing gun produces a torque T resulting in an upward directed torsion of the wrist of the operator, which is undesired from an ergonomic point of view. Furthermore, if the trigger 3 is not provided with a retainer mechanism, which when desired locks the trigger 3 in the activated position, a solution which as mentioned previously is undesirable for safety reasons, it is necessary for the operator during use of the washing gun constantly to press the trigger 3 towards the handle portion leading to fatigue of the finger muscles of the operator. This required constant activation of the trigger 3 is however not being aided by the reaction force F from the jet. Figure 2 shows a first embodiment of a washing gun according to the invention. The washing gun 5 comprises a nozzle section 8 and an inlet 11 for washing fluid. The hand grip section generally designated by 9 is according to this embodiment subdivided into two sections: an upper section 9" placed above a plane P extending through the longitudinal axis 2 of the nozzle section 8 and a lower section 9' located below said plane P in that part of the hand grip which comprises the trigger 6. As shown in figure 2, the upper section 9" is shaped to accommodate the index finger of the operator's hand during operation of the washing gun 5. Figure 3 shows a second embodiment of a washing gun according to the present invention generally designated by 5'. The fluid jet 7 produces during operation of the washing gun 5 a reaction force F on the nozzle section 8 of the gun 5. The longitudinal axis 2 through the jet 7 coinciding with the reaction force F is contrary to the case of the prior art washing gun shown in figure 1 coincident with the longitudinal axis through the forearm of the operator. This is accomplished by positioning the hand grip section 9 substantially symmetrically with said longitudinal axis 2 through the nozzle section 8. The trigger could in principle be placed anywhere on the hand grip section 9, 9', for instance on that part of the hand grip section 9 facing the nozzle section 8, which position would correspond somewhat to the position of the trigger in the prior art washing gun 1 shown in figure 1. It is, however, as mentioned previously advantageous to position the trigger 6 at that part of the hand grip section 9, 9' which is facing away from the nozzle section 8, so that the reaction force F on the nozzle section 8, and hence on the hand grip section 9, 9' will facilitate maintained activation of the trigger 6 during operation. Although two specific embodiments of the present invention have been shown and described in the preceding parts of the detailed description, it is understood that a person skilled in the art may conceive other embodiments of the invention without departing from the scope of the invention as defined by the following claims. PART LIST 1. Prior art washing gun 2. Longitudinal axis through jet and nozzle part of washing gun 3. Prior art trigger 4. Longitudinal axis through forearm of operator 5. Washing gun according to a first embodiment of the present invention 5' Washing gun according to a second embodiment of the present invention 6. Trigger 7. Jet of washing fluid 8. Nozzle section 9. Hand grip 10. Trigger part of hand grip 11. Washing fluid inlet

Claims: CLAIMS: 1. Washing gun comprising a nozzle section (8) with a longitudinal axis (2) for the de- livery of a washing fluid and hand grip means (9, 9', 9") for holding the washing gun during operation hereof, which washing gun is furthermore provided with a trigger (6), characterised in that said hand grip means (9, 9', 9") extends on either side of the horizontal plane (P) containing the longitudinal axis (2) of the nozzle section (8). 2. Washing gun according to claim 1 , characterised in that said hand grip means (9) is subdivided in two sections, the first section (9") being positioned above said horizontal plane (P) and the second section (9') being positioned below said horizontal plane (P). 3. Washing gun according to claim 2, characterised in that said first section (9") is formed to accommodate the index finger of the user's hand during operation of the washing gun. 4. Washing gun according to claim 1 , characterised in that said hand grip means (9) is connected to said nozzle section (8) in such a manner that the hand grip means (9) is oriented substantially perpendicular to and symmetrical about said longitudinal axis (2). 5. Washing gun according to claim 4, characterised in that said longitudinal axis (2) during operation of the washing gun substantially coincides with the longitudinal axis (4) through the forearm of the user. 6. Washing gun according to any of the preceding claims, characterised in that said trigger (6) is positioned on said hand grip means (9). 7. Washing gun according to claim 6, characterised in that said trigger (6) is positioned on that part of said hand grip means (9) which is facing away from said nozzle section (8).

Inventors: ASP FLEMMING, CHRISTENSEN KENNETH, ASP, FLEMMING, CHRISTENSEN, KENNETH
Applicants: ALTO DANMARK AS, ASP FLEMMING, CHRISTENSEN KENNETH, ALTO DANMARK A/S, ASP, FLEMMING, CHRISTENSEN, KENNETH
Application year: 2001
Main classification: B08B3
IPC codes: B05B9, B05B15, B08B3