A TRIGGER DEVICE FOR COMPUTER MOUSE

Abstract: A computer mouse trigger device includes a support arm (11) which joins the mouse (1) so as to extend above the upper side of the mouse. The arm is pivotal relative to the mouse and is carried thereby through the medium of spring means. That side of the arm (11) facing towards the mouse carries a shoulder (13) in alignment with a click key (2) on the mouse (1). The spring means of said arm (11) enables the user's index finger (3) and/or middle finger (3') to rest confortably on the upper side of the arm (11) so that a key (2) can be clicked by applying a slight force via the arm (11) and the shoulder (13).

Description: A TRIGGER DEVICE FOR COMPUTER MOUSE The present invention relates to a computer mouse trigger device of the kind defined in the preamble of Claim 1. The most common commercially available computer mouse is basically shaped to fit comfortably in a cupped hand of the user with the user's forearm resting on a horizontal surface, for instance on the top of a table. The computer mouse normally comprises a body that has a curved, convex upper side and a flat underside in which a roller ball is fitted for rolling on the mouse supporting surface as the mouse is moved thereon. Two laterally separated click keys are normally mounted on the upper side of the mouse body on respective sides of a longitudinal mouse body symmetry plane. The click keys are weakly spring biased, so that they can be manipulated with a slight downwardly acting finger pressure. One problem associated with a computer mouse is that the user will instinctively and physiologically press the mouse key with the tip of his index finger. When the cupped hand of the user embraces the mouse and rests against the supportive surface around the mouse perimeter, the user's hand and forearm muscles are essentially relaxed, even when moving the mouse on the mouse supporting surface. However, immediately the user prepares to click a mouse key, he/she will bend his finger so that the top of the finger is spaced above the mouse key in a preparatory position. The user will normally keep his finger in said preparatory position above the mouse key even as he/she moves the mouse on the mouse supporting surface, in other words practically constantly between key clicking operations. The user is therefore often subjected to prolonged strain in his hand and forearm, resulting in symptoms of an affliction often referred to as "mouse arm" . The object of the present invention is to provide a computer mouse trigger device which enables the danger of mouse arm to be minimised. The inventive trigger device may constitute part of the mouse as delivered by the manufacturer. Alternatively, the trigger device can be manufactured separately and subsequently fitted to an existing conventional computer mouse. The object of the invention is achieved with the trigger device according to the accompanying Claim 1. Further embodiments of the trigger device will be apparent from the dependent Claims. An important feature of one preferred embodiment of the invention resides in the provision of a springy, elastic support arm which is supported at only one end thereof, i.e. in a cantilever fashion, and which extends above the region of the mouse click keys and which includes on its underside a shoulder that faces towards one of the keys. The springiness of the arm and its flexural rigidity are chosen so that the user can accommodate the mouse in its natural position in the cup of his hand, while the index finger and/or middle finger can be rested comfortably on the upper side of the arm, generally plane-parallel with the undersurface of the mouse, without needing to tense the muscles in hs hand or forearm in order to prevent his fingers from clicking on the key under the influence of gravity (and tension against a curved "normal position") via the support arm and the shoulder. On the other hand, the flexural rigidity of the arm and its springiness are chosen so that the user can click the mouse with comfortable, slight downward finger pressure on the arm. The arm is suitably adapted to support the pressure along its full length, so that the finger and forearm muscles can be kept relaxed. In some of the embodiments at present preferred, the shoulder may be arranged on the arm for movement in the longitudinal direction of the mouse along a guide that extends along the mouse symmetry plane. This enables the force that must be applied for blocking purposes to be set, i.e. outward bending of the support arm required for the shoulder to actuate the key. The shoulder may be asymmetrical and laterally reversible so as to enable its free end to be brought into engagement with one or the other of said two laterally separated clicking keys. In the case of other embodiments of the inventive device, the arm of said trigger device may be connected to an attachment which can be or is connected to the mouse, and then particularly to the upwardly convex, arched body of the mouse. This attachment may include a support on each side of the mouse in the vicinity of the level of the generally flat underside of said mouse. The supports are therewith able to serve to support the middle-finger side and thumb-side of the hand in which the computer mouse is gripped. The invention will now be described in more detail with reference to the accompanying drawings. Fig. 1 illustrates schematically and in side view a computer mouse that includes the inventive trigger device. Fig. 2 is a view taken on the line II-II in Fig. 1. Fig. 3 shows the main part of the trigger device from above. Fig. 4 is a partially sectioned view taken on the line IV-IV in Fig. 3. Fig. 5 is a perspective reproduction of the subject of Figs. 3 and 4. Fig. 6 illustrates a shoulder that can be fitted to the springy arm of the trigger device for coaction with a mouse click key. Fig. 7 is a schematic illustration of the movement pattern of the index finger of one hand with which a conventional computer mouse is operated. Fig. 7 is a side view of a computer mouse 1 that includes a click key 2. The index finger 3 of a user's hand 4 that rests comfortably on the surface of a table 5 is shown in full lines in preparation for clicking on the key 2. A comfortable starting position of the index finger is shown in broken lines and referenced 3', from which it will be seen that the mouse 1 conforms well to the user's cupped hand, which snugly embraces the upper curved surface of the mouse. There is a serious danger that the user will experience pain in those muscles that are associated with holding the index finger 3 in said preparatory position above the key 2. For this reason, there is provided in accordance with the invention a trigger device 10 that comprises a springy, elastic blade-like arm 11 which is mounted on the mouse solely at one end in cantilever fashion and which extends generally parallel with the underside 6 of the mouse, said underside being generally parallel with the table surface 5. The arm 11 is mounted on the mouse 1 with the aid of an attachment 12 and extends along the longitudinal axis of the mouse above the upper surface thereof and bridges the mouse symmetry plane P (Fig. 2). The arm 11 carries on its undersurface a shoulder 13 whose bottom end is located above one (2) of the keys 2, 2'. As will be seen from Fig. 1, the user's hand 4 basically retains the comfortable position indicated in broken lines in Fig. 7, with the exception that the index finger 3 and/or the middle finger 3 ' is carried generally straight and horizontally along substantially its full length by the support arm 11 without support of the fingers 3, 3' generating any tension in the hand muscles or forearm muscles. All that is required to click on the key 2 is for the user to momentarily apply a downwardly acting force on the arm 11 from the rest position illustrated in Fig. 1 in which muscle tension is relaxed. The flexural resistance/springiness of the arm 11 is chosen to enable the arm to bend downwards to click on the key 2, via the shoulder 13, in response to a comfortable, slight force. It will be seen from Fig. 2 that the attachment 12 has two wings 121, 122 for comfortable support of the little finger side and the thumb side of the user's hand, therewith reducing friction of the hand against the table surface- 5. Fig. 6 is an end view of the asymmetric shoulder 13 and shows that the attachment end of the shoulder has undercut surfaces which can be caused to grip one of a pair of correspondingly shaped strips 17 on the underside of the arm 11. This arrangement enables the shoulder 13 to be moved to any chosen position along the strip 17 and held in this position by friction. If so desired, the user can pull the shoulder 13 away from the strip 17 and turn the shoulder through 180° and then replace the shoulder on the strip 17, wherewith the free end of the shoulder 13 will now be in alignment with and coact with the other key 2 ' . It will be seen that the user can click on the key that is not operated via the shoulder 13, with one of his fingers. In the illustrated embodiment, the attachment 12 has a central U-shaped part whose configuration closely conforms to the upper part of the mouse 1, said attachment 12 being connected to the upwardly facing outer casing of the mouse by pieces of adhesive tape 18, or some corresponding adhesive join, weld join or the like. The embodiment illustrated in Figs. 1-6 can thus be fitted to an existing computer mouse, although it will be understood that the invention can also include a computer mouse that has been provided with an arm 11 in some other way and which may, for instance, be an integral part of the mouse shell or connected to the mouse body in some other way. Although the support arm has been shown to be of a cantilever-like construction and bendable in the height direction of the mouse, it will be understood that the arm may be carried for pivotal/bending movement in some other direction, for instance along a plane that extends transversely to the longitudinal centre plane of the mouse. It will also be understood that the support arm can be given its characteristic properties - its pivotal and springy properties - for instance by the arm being carried by the attachment through the medium of a pivot means or by supporting the arm from the mouse or the arm attachment through the medium of a spring. In the case of the illustrated embodiment, the arm, and particularly that part which is connected to the attachment, can be considered to afford a pivoting option and an arm spring means.

Claims: CLAIMS 1. A computer mouse trigger device, characterised by a support arm (11) carried by the mouse (1) and extending over the upper side of said mouse (1) ; in that the arm (11) has on the side thereof that faces the mouse a shoulder (13) positioned in alignment with a mouse click key (2); in that the arm (11) is pivotal towards and away from the key and is carried by the mouse through the medium of spring means that permits the user's index finger (3) and/or middle finger (3') to rest comfortably on the upper side of said arm (11) so as to enable the key (2) to be clicked by a slight force applied via the arm (11) and the shoulder (13) . 2. A trigger device according to Claim 1, characterised in that the shoulder (13) is arranged for movement along the arm (11) in the longitudinal direction of the mouse. 3. A trigger device according to Claim 1 or 2, characterised in that the shoulder (13) is arranged for movement along a guide track (17); and in that the shoulder is asymmetrical and can be reversed on the track (17) to permit the asymmetric free end of the shoulder (13) to be brought into alignment with one of two click keys (2, 2') laterally spaced on the mouse. 4. A trigger device according to any one of Claims 1-3, characterised in that the support arm (11) has an attachment (12) formed integrally therewith; and in that the support arm is an accessory that can be fitted to a computer mouse (1) with the aid of a joint means (18), such as a glue joint. 5. A trigger device according to any one of Claims 1-3, characterised in that the arm (11) is an integral part -of the mouse ( 1 ) . 6. A trigger device according to any one of Claims 1-5, characterised in that the support arm is integral with the attachment and extends therefrom in cantilever fashion, wherein the support arm is springy and resiliently flexible, and wherein the spring means is formed by the flexural rigidity of the cantilever arm.

Inventors: HAEFFNER MIKAEL, HAEFFNER, MIKAEL
Applicants: HAEFFNER MIKAEL, HAEFFNER, MIKAEL
Application year: 1999
Main classification: G06K11
IPC codes: G06F3