FR2540774A1 - Control device for articulated handles on a work site tool - Google Patents

Abstract

The invention relates to a jack hammer or the like whose two handles such as 4 are suspended. The lever 12 securely fastened to the handle 4 carries the trigger 5 which actuates the pusher 9 of the energy switch 6 (compressed air, electricity, or pressurised liquid). The driver 17 actuated by the trigger 5 is in contact with the pusher 9 on the geometric axis 26 around which the assembly 4, 5, 12 oscillates. Application: eliminating operational jolts when the suspended handles oscillate.

Description

 The present invention relates to a percussive or rotary-percussive tool known as a jackhammer, concrete breaker or perforator, whatever its energy source, It is known that such an apparatus includes handles for holding and guide the tool, on the one hand and to control the start or stop on the other hand. The control trigger acts on the energy supply device which is generally arranged laterally on the body of the hammer.

 Since such a tool is subjected to significant vibrations, attempts have been made to make its use less painful for the worker by suspending the handles relative to the body of the device.

 When the handles are oscillating relative to the body of the device, a problem arises for the transmission of the movement of the trigger trigger. Indeed, it is traditionally carried by a handle, with which it therefore dares. On the other hand, the switch to be actuated (compressed air distributor, electrical switch, hydraulic valve or other) is integral with the body of the device. This therefore results in the appearance of jerks in the operation of the device due to the oscillation of the poi f; neas.

 The object of the present invention is to avoid these drawbacks and to carry out a command whose functionality is independent of the oscillations of the handles and their tip.

 The device according to the invention, intended to equip a tool on the body of which are articulated two oscillating handles, one of which carries a trigger trigger, while moreover the energy arrival switch actuated by the trigger is integral with the tool body, is characterized in that the switch has an opening pusher capable of receiving at its end the thrust of a cleat connected to the trigger and oscillating with it and the handle, the point of contact of the pusher and cleat being substantially located on the geometric axis around which the handle in question oscillates.

Thus, the supply of energy in the hammer takes place in a sensitive way, corme on a hammer clas
sique not suspended. So we keep the trigger on a poig
born oscillating, while the control remains fixed on the
unsprung body of the hammer, so that the distribution
of energy is carried out in a way as simple as on a
unsprung hammer.

According to another characteristic of the invention
tion, we insert between the trigger and the valve of com
mande, a rocker which reverses the movement of the trigger
so as to depress the control button when the u
the user also pushes the trigger on the handle.

The attached drawing given by way of example not
limiting will allow a better understanding of the characteristics
of the invention.

Figure 1 is a general view of a hammer
concrete breaker equipped according to the invention0
Figure 2 illustrates the kinematics of the oscillating handles.

Figure 3 is an axial section of the head of the
hammer when in the rest position.

Figure 4 is a similar section in progress
of use, that is to say when the operator presses the door
compressed air inlet trigger.

Figure 5 is a perspective view of the
trigger.

Figure 6 is an analog view of the rocker arm
18 only.

Figure 7 is a section along VII - VII
(figure 4).

A bri hammer has been shown in the drawings
se-concrete 1, whose body is surmounted by a rigid head
2. In this head are arranged two handles 3 and 4 which
are articulated with respect to the head 2 (double arrows 15
To do this, the lever 11 of the handle 3 oscillates at
turn of a hinge pin 13 with transverse axis, while
that the lever 12 which crosses it oscillates with its handle 4
around the geometric axis 26 of a pin 14.

ssu above handle 4, is at the ma
niere known a control trigger 5. On the side of the
head 2 is the body of a control valve 6 provided with a connection end piece 7 intended to receive an energy inlet pipe 8.

The inlet valve 6 comprises, in the known manner, a release button 9 provided with one end
upper rounded 10 (Figure 4).

According to one of the characteristics of the invention, it is arranged that the geometric axis of the pin 14, at
turn which can pivot the assembly 4, 12w (arrow 16) is located on the rounded top 10 of the pusher 9 of the control valve 6. Thus, the oscillation of the hanging handle 4 and its lever 12 around the pin 14 has no effect on the open or closed longitudinal position of the pusher 9 when the latter is actuated by the cleat. 17 of a rocker arm 18, which will now be described.

 The trigger 5 is integral with a fork 19, the two arms of which terminate in openings 20 intended to receive a hinge pin 21 (FIGS. 4 and 5).

This axis 21 is fixed in the lever i2 of the handle 4.

 Furthermore, two openings 22 are provided facing halfway along the arms of the fork 19, to receive a pin 23 also passing through an opening 24 of the rocker arm 18. This opening 24 is placed between the cleat 17 fitted to one -the ends of the rocker arm 18, and a support grain 25 located at its other end.

 After mounting the rocker arm 18 between the arms of the fork 19, it can be seen (FIGS. 3 and 4) that if the operator presses the trigger 5 against the handle 4 (as indicated by arrow 26), the axis 23 is lowered and, the rocker 18 taking support by its grain 25 on the lever 12, its end stop 17 also tends to lower. The whole of this mechanism therefore makes it possible to reverse the movement of the trigger 5 and to press on the pusher 9 when the trigger is pressed 5. As previously indicated, this push on the rounded top 10 takes place exactly on the axis 26 of the articulation pin 14, so that the position of the pusher 9 remains independent of the orientation of the suspended oscillating handle 4 (double arrow 16).

 The switch 6 remains on the unsuspended part 2 of the hammer 1, which eliminates any problem of communication between the suspended and unsprung parts.

Claims (3)

 1 - Control device for a tool on the body of which are articulated two oscillating handles, one of which carries a trigger trigger, while moreover the energy arrival switch actuated by the trigger is integral with the body of the tool, characterized in that the switch has an opening pusher (9) capable of receiving at its end (10) the thrust of a cleat (t7) connected to the trigger (5) and oscillating with it and the handle ( 4), the point of contact of the pusher (9) and the cleat (17) being substantially located on the geometric axis (26) around which the handle (4) oscillates.  2 - Control device according to claim 1, characterized in that between the trigger 5 and the pusher (9) of the control valve (6), a rocker arm (18) is interposed which reverses the movement of the trigger (5) so as to depress the pusher (9) when the user also depresses the trigger (5) on the handle (4).  3 - Control device according to claim 2, characterized in that the trigger (5) is extended by the two arms of the fork (19) articulated at its end (20) on an axis (21) carried by the lever (12 ) of the handle (4), while both. fork arms (19) have openings receiving a transverse axis (23) on which the part is articulated. central of the rocker arm (18), the latter having at one end a grain (25) capable of bearing on the bottom of the lever (12) near the handle (4) while at its opposite end it comprises the cleat (17 ) likely to bear on the rounded end of the pusher (9).