FR2740065A1 - POWER TOOL - Google Patents

Abstract

A power tool is provided comprising a main housing (22) containing a motor for controlling a shaping element and a hollow handle (28) connected to the housing. An actuator vane is mounted to allow relative pivoting of the handle (28) and can pivot between (1) an open position in which the motor is deactivated and (2) a closed position in which the motor is activated to control the motor. 'shaping element. When the pallet is in the closed position, its release causes the pallet to return to the open position to deactivate the motor. A locking member is mounted on the pallet to be movable together with the pallet whereby with the pallet in the closed position the locking member is able to hold the pallet (38) in the closed position when the pallet is. released.

Description

The present invention relates to actuators for tools

  motor, and more particularly, paddle actuators provided with a locking mechanism. Trigger-type mechanisms are known for controlling a motor tool in which it is necessary to continuously press the trigger in order to close the switching circuit intended to supply power to the motor of the tool. We also know the implantation on these power tools of locking mechanisms so that an operator does not need to continuously press the trigger mechanism to control the tool. Such locking mechanisms avoid operator fatigue and thus allow

  improved operator control of the tool.

  Although these locking mechanisms are known, they are normally external to the trigger mechanism so that they often require an operator to move his hand to modify his grip on the trigger, or to use his other hand, so as to place the locking mechanism in its operational locked state. The use of two hands to operate the tool and use the locking mechanism is not desirable as it complicates the use of a locking mechanism and prevents the other hand from being able to be used for other functions during of the

implementation of the tool.

  In addition, when the locking mechanisms can be simultaneously triggered by the same hand as that which controls the trigger, the locking mechanisms still generally require a movement distinct from the movement of the trigger, in particular in opposite or lateral directions, which complicates still using a locking mechanism. When the hand controlling the trigger can be used, the separate movements necessary and the relative positions of the triggering and locking mechanisms which cause a modification of the operator's grip on the trigger to allow the operator to control and using the aforementioned locking mechanism together increase the possibilities for the operator to reduce the pressure to be applied to the trigger with his hands when controlling and using the locking mechanism with the same hand. Such a pressure reduction applied to the trigger can correspondingly allow the movement of the locking mechanism from its depressed position so as to deactivate the motor and requires a further depressing of the operator on the trigger mechanism and once again an attempt to trigger and move the locking mechanism without deactivating the motor. This is not particularly desirable when the tool has already engaged its shaping element with the surface to be shaped due to the damage that can be caused to the surface to be shaped and / or to the tool by sudden ruptures of I ' tool feed and the rapid speed decrease induced

the shaping element.

  When the power tool controls its shaping element along an orbital path, as in orbital polishers and their associated discs, the operator experiences a significant increase in the vibrational reaction of the tool compared to other tools. which do not implement an orbital command. Such a vibration reaction increases the need for an easy-to-use actuator and for locking mechanisms, particularly when the operator moves the polishing machine away from his body to reach remote areas, such as external surfaces. of an automobile, from a relatively fixed position. As the operator stretches their arms, the weight

  of the polishing machine further accentuates the door

  false outwards which makes the control of the polishing device and, consequently, the continued use of the actuator, more difficult. In a position offering such an extension, it is particularly desirable that the locking mechanism of the actuator is placed ergonomically

  and usable so as to allow easy and immediate use.

  In accordance with the present invention, a power tool with an actuator and a locking mechanism is provided in order to solve the above-mentioned problems arising from the prior art. According to one form of the invention, the power tool includes a main housing containing a motor intended to control a shaping element and a hollow handle connected to the housing. An actuator pallet is mounted for a pivoting movement relative to the handle and can pivot between (1) an open position in which the motor is deactivated and (2) a closed position in which the motor is activated in order to control the shaping element. When the pallet is in the closed position, releasing the pallet causes the pallet to return to the open position to deactivate the motor. A locking member is mounted on the pallet to be moved at the same time as the latter whereby the pallet being in the closed position the locking member the member is capable of holding the pallet in the closed position when the pallet is released . With the locking member mounted on the pallet so as to move with the pallet when the pallet is pivoted, the motor tool presented makes it easier for an operator the operation of triggering the locking member relative to the prior locking mechanisms which were not mounted to allow the

  movement with the trigger mechanism.

  According to one embodiment, the handle has an elongated, arcuate shape and extends away from the housing and the pallet has a

  elongated, arcuate shape practically conforming to the shape of the handle.

  The handle may include a pallet receiving slot over the length thereof, the pallet being mounted in the handle to exit the slot and allow the pallet to be pushed into the slot when the latter passes from the open position to the closed position. The elongated, arcuate shape of the corresponding or handle-like actuator creates an ergonomic control mechanism in that an operator can easily operate the tool while grasping the arcuate handle in

  various positions in the region it can reach.

  The pallet may include an opening for the locking member including a button portion projecting through the pallet opening and a cam portion in the hollow handle. A flange can be mounted in the hollow handle so that when the pallet is moved to the closed position, the button member can be pushed into the pallet opening to cause the cam portion to snap onto the flange and hold the pallet in the closed position

when the pallet is released.

  The handle may have a switching structure mounted inside for starting the engine and the pallet may have a control member, the pallet being mounted on the handle so that in the open position the control member is remote. of the switching structure and the motor is deactivated and in the closed position, the control member triggers the switching structure

  to start the engine.

  According to one form, the cam structure is proposed to make the handle and the locking member contribute to the movement of the locking member between (1) an unlocked position in which the pallet is freely movable between its open and closed positions and (2) a locked position in which the pallet is kept in the closed position. The handle may include a flange mounted therein and the locking member may include a portion extending inside the handle. The cam structure may include a cam surface on at least one of the flanges and the locking member which allows the part to snap onto the flange when the locking member is moved from the

  unlocked position to locked position.

  According to one form, the pallet has a length and distant ends and the locking member is mounted to be able to pivot on one end of the pallet and the pallet is mounted to be able to pivot on the

  housing at the other end of the pallet.

  According to another form of the invention, the power tool is provided with a control pallet mounted so that it can pivot relative to the handle when the movement of the handle towards a functional position in a first direction causes the control of the shaping element by the motor. A locking member is mounted to allow pivotal movement relative to the pallet, in which movement of the locking member in the first direction is capable of locking the pallet in its operative position. With the locking member mounted on the pallet and the pallet on the handle so that the movement of one or the other in the same direction, i.e. pressed inwards from the handle, can activate the motor the power tool, an operator no longer has to deal with two different movements which must be carried out with the hand grasping the handle of the power tool so as to lock the tool in its operational state. This significantly simplifies the use of

  locking mechanisms of the present invention.

  Preferably, the handle has a hollow inner part and has a slot. Pallet can be mounted in the slot pallet can be pushed into the slot in the first direction inward

  of the handle to be thus moved into its operational position.

  According to one form, the pallet and the locking member can together be pushed in the first direction towards the inside of the handle so as to maintain the pallet in its operational position and

  easily allow the tool to be operated with one hand.

  According to another form of the invention, a handle switch is electrically connected to the motor and has active and inactive states so that when the switch is in the active state, the motor is activated to control the shaping element and in the inactive state, the motor is deactivated. A paddle actuator is mounted for movement relative to the handle between (1) an extended position in which the actuator extends a first distance from the handle and the switch is in the inactive state and ( 2) a first depressed position in which the actuator extends a second distance from the handle less than the first distance and the switch is in the active state. A locking member is carried by the pallet actuator and is capable of being depressed with the pallet in the depressed position to lock the pallet in the depressed position. When the pallet is in the first locked locked position, the pallet can be pressed again in a second position in which the pallet actuator extends at a third distance from the handle less than the second distance. In the second depressed position, the locking member and the pallet are released from the first locking position to allow the pallet to move to its extended position when the pallet is released by the operator to turn the switching mechanism. and, consequently, the power tool, in its deactivated state. In this way, the power tool can be activated, locked in its active state and then released from the locked state by movement of the paddle and the associated locking member in a single direction, providing a tool for significantly easier to use motor compared to those which require different movements to implement and release their locking mechanisms

  from the movement of their trigger.

  According to one form, a locking flange is mounted in the hollow handle and the locking member includes a member constituting a cam in the hollow handle arranged so that when the pallet is in its first depressed position, the member constituting a button can be pushed into the pallet opening to cause the cam member to engage and snap onto the flange and maintain the

  pallet in the first position pressed when the pallet is released.

  The characteristics and advantages of the invention will also emerge

  of the description which follows with reference to the appended drawings o:

  Figure 1 is a perspective view of a device for encircling, sanding, polishing or the like according to the present invention; Figure 2 is an elevational view of the left side of the device shown in Figure 1, having a front handle and a rear handle and a paddle actuator on the rear handle; Figure 3 is a top plan view of the device shown in Figure 1 showing in detail the engagement of a first and a second housing shell member which defines a cord lock

and a collar for a male plug.

  Figure 4 is an elevational view of the right side of the device shown in Figure 1; Figure 5 is a rear elevational view of the apparatus shown in Figure 1; Figure 6 is a bottom plan view of the device shown in Figure 1 showing the counterweight assembly comprising an amount to

  quick exchange for mounting a polishing pad.

  Figure 7 is an enlarged top plan view of the cord locking assembly, the collar and the plug of the device shown

  by FIG. 1, as it appears in FIG. 3.

  Figure 8A is a sectional side view taken along lines 8A8A of Figure 7; Figure 8B is a sectional side view taken along lines 8B-8B of Figure 7; Figure 9 is a rear sectional view taken along line 9-9 of Figure 7; Figure 10 is an exploded perspective view of the device shown in Figure 1 showing the arrangement details of the DC motor with a support plate and a straightening assembly, a vane actuator with a button locking, as well as the counterweight and buffer assemblies; Figure 11 is an enlarged perspective view of the motor and support plate assembly and the paddle actuator and its locking mechanism mounted in the first housing shell member shown in Figure 10; Figure 12 is an exploded perspective view of the paddle actuator and locking button assembly shown in Figure 16; FIG. 13 is a side elevation view, in partial section, of the mounted paddle actuator and locking button assembly shown in FIG. 10; FIG. 14 is a perspective view of the mounted support plate and straightening assembly represented by FIG. 10; Figure 15 is an exploded view of the support plate and rectifier assembly shown in Figure 14; FIG. 16 is a side view in section of the counterweight and polishing pad assembly showing a mounting plate for the pad and a mounting post and the retaining ball inserted through an axial reinforcement of the mounting plate of the sanding pad Figure 17 is an enlarged sectional view of the support post and the axial reinforcement shown in Figure 16 showing a circumference groove in the axial reinforcement with the retaining ball in the groove; Figure 18 is an enlarged sectional view of part of the device shown in Figure 17, showing the amount inserted through the axial reinforcement with the retaining ball flush with the bottom of the reinforcement in order to reversibly fix the buffer to the amount ; Figure 19 is a side sectional view of the upright showing the retaining ball connected to a plastic support which is integral with a withdrawal of the upright; Figure 20 is an enlarged perspective view of the first housing shell member; Figure 21 is an enlarged perspective view of the second housing shell member; Figure 22 is a schematic electrical diagram of the assembly

  DC motor according to the present invention.

  FIG. 1 illustrates an ergonomic device 10 intended for drawing, polishing, sanding or the like, according to the present invention. The device 10 according to the invention has a symmetrical shape according to a vertical reference plane, not shown, extending so

  central from a front end 12 to a rear end 14.

  The device 10 includes a housing 16 preferably provided with a first housing shell member 18 and a second housing shell member 20 which, when connected to each other, define a dividing line 21 s 'extending in a vertical reference plane along which the housing 16 is symmetrical, as shown in Figure 3. Preferably, the first and second housing shell members 18 and 20 are molded plastic their different parts described in this document being adapted the to each other. The corresponding parts of each of the symmetrical housing members 18 and 20 are identified by the same reference number, the parts of the first housing member 18 being provided in addition with the letter "a" and the parts of the second housing member

20 having the letter "b".

  The housing 16 includes a main central housing 22 in which is

  mounted the motor assembly 24, clearly represented by FIGS. 10 and 11.

  The main central housing 22 includes a front handle 26 and a rear handle 28 in extension thereof. As shown in Figures 1 to 6, the main central housing 22 includes a substantially flat top 30 and a lower part 32 and the front and rear handles 26 and 28 extend transversely towards each other the front handle 26 extending horizontally outwards towards the front end 12 from the main central housing 22 between and practically parallel to the top 30 and to the bottom part 32 thereof while the rear handle 28 extends outwards towards the rear end 14 from the main central housing 22 and extends vertically and in an arc between the

  top 30 and the bottom part 32 of the main central housing 22.

  The rear handle 28 has a hollow interior 34 in which a box-shaped switch housing 36 for a switching mechanism 37 shown schematically in Figure 22, and an actuator pallet 38 are mounted. The actuator pallet 38 extends from the interior 34 through a low slot 35 made in the handle 28 at a predetermined distance outside the hollow interior 34 of the handle

  rear in a grip opening 39 limited by the rear handle 28.

  The pallet 38 has an arcuate shape corresponding practically to the contour of the rear handle 28 so as to allow easy and easy operation when the user grasps the rear handle 28 by its part in

  arc shape as will be described below.

  At the top 30 of the housing 16, a raised region forming a wedge-shaped collar 40 is formed in which a male plug or connection socket 42 can be mounted in order to receive a socket socket head of an electric cord (not shown) for electrically connect an alternating power source, at 110 volts at 60 Hz, to the motor assembly 24. Adjacent to the collar region 40 towards the rear end 14 of the housing 16, a cord locking mechanism 44 is

  defined in the apex 30 of the housing, as shown in FIGS. 7 to 9.

  The cord locking mechanism 44 prevents accidental disconnection of the female plug connected to the collar region 40 of the male plug 42. Thus, the motor 24 being activated to control a shaping element, such as a buffer of polishing 46, and the polishing pad 46 being controlled along an orbital path as described below, the aforementioned shape of the housing 16 allows an operator to easily handle the device 10 of the present invention with both hands to exercise control according to two planes on the device 10 while the polishing pad 46 is moved over the shaping surface according to its orbital path without having to grip the main housing II 22 to guide and efficiently and precisely control the pad 46 on the shaping surface. Furthermore, the establishment of the electrical connection between the device 10 and the electrical cord for supplying alternating current thereof in a recessed location at the top 30 of the housing and the cord locking mechanism 44 being adjacent to that -this keeps the bead in place away from the interface between the pad 46 and the surface being shaped, for example for bodywork finishes, which at the same time limits disconnections interrupting the processes of encircling, sanding or polishing in which the

device 10 can be used.

  Now examining more specifically the configuration of the housing 16, it is remarkable that the first and second housing shell members 18 and 20 contribute to the formation of the front and rear handles 26 and 28, of the collar region 40 and of the locking mechanism. cord 44 described above. More specifically and with reference to FIG. 3, the first housing shell member 18 includes a half of main housing part 22a, a front handle half 26a, a rear handle half 28a, a collar region half 40a and a half of cord locking mechanism 44a. Likewise, the second housing shell member 20 includes one half of main housing part 22b, one half of front handle 26b, one half of rear handle 28b, one half of collar region 40b and one half of cord locking mechanism. 44b. The first housing shell member 18 is provided with threaded protrusions 48 and the second housing shell member 20 is provided with embedded recesses 50 formed inside thereof each of the recesses 50 corresponding to a threaded protuberance 52, like the indicate

Figures 10, 20 and 21.

  To assemble the device 10, the internal components comprising the motor assembly 24, the switch housing 36, the actuator pallet 38 and the connection socket 42 are mounted on the first housing shell member 18, as shown in FIG. Figure 11, the second housing shell member 20 then being disposed against the first housing shell member 1 8 so as to align the threaded protrusions 52 of the second housing member 20 with the corresponding threaded protrusions 48 of the first housing shell member 18. When the housing members 1 8 and 20 are thus aligned, the screws 54 introduced into the threaded protrusions 52 can be, in turn, introduced into the protrusions 48 to fix the housing shell members 1 8 and 20 one to the other other the heads of the screws 54 being placed in the recesses embedded 50 of the

  second member of housing 20 so as not to exceed it.

  When the first and second housing shell members 18 and 20 are attached to each other, the main housing portion halves 22a and 22b help define an interior space 56 in which the motor assembly 24 is mounted. As clearly shown in Figure 3, the main housing portion 22 thus formed has a pear-shaped cross-sectional configuration. The raised collar region 40 has a triangular cross section, and, as previously mentioned, protrudes from the substantially flat top 30 of the housing 16. The wedge-shaped collar region 40 has a central area

  recessed oblong 58 in which the connection socket 42 is placed.

  On examining the configuration of the front handle 26, each of the main housing part halves 22a and 22b has a linked triangular part 60a and 60b, respectively, which extends horizontally outward and forward from main housing parts 22a and 22b between and practically parallel to the top 30 and the bottom part 32 of the housing. From the outermost front corner of the triangular parts 60a and 60b are extended respectively channel-shaped straight sections 62a and 62b so that the housing shell members 18 and 20 being connected to each of them, the straight sections in channel shape 62a and 62b extend substantially parallel to each other and the channels open opposite one another. The straight sections 62a and 62b extend forward in channel-shaped grip portions 64a and 64b, respectively, which extend at an angle from their respective channel-shaped straight sections 62a and 62b toward forward towards each other to the distal ends 66a and 66b which are contiguous to each other along a dividing line 21 and define a folded section of the front handle 26 in which the channels open back towards the main housing 22 the housing shell members 18 and

being linked.

  Intermediate horizontal support members 67a and 67b extend inside the channels of the respective cross sections 62a and 62b and the channel-shaped angular parts 64a and 64b, as clearly shown in Figures 20 and 21. The corresponding protrusions 48 and 52 are formed on the intermediate support members 67a and 67b at the distal ends 66a and 66b and can be in alignment with one another when the housing members 18 and 20 are assembled so that one of the screws 54 introduced into the threaded protrusions of aligned front handle will allow fixing between the housing members 18 and 20 and the distal ends of front handle 66a and 66b. In this way, the front handle 26 is produced by constituting a front grip opening 69 by the connection

  mentioned above between the parts having an angle 64a and 64b.

  The housing shell members 18 and 20 further comprise rear handle arc grip portions 68a and 68b which extend integrally from the approaches of the rear end of the apex 30 of the main housing 22 and, more specifically, from the 'rear of the cord locking mechanism 44. The arc grip portions 68a and 68b continue rearward and vertically downward to a point aligned with the bottom portion 32 of the main housing 22 so as to extend substantially in a quarter circle. At this point, the rear handle 28 has rectilinear connection sections 70a and 70b, respectively, which extend from their respective rear handle arc grip portions 68a and 68b back to the main housing portions 22a and 22B on the lower part 32 thereof. To connect the rear handle parts 28a and 28b, one of the threaded protrusions 48 is produced in the arc grip parts 68a and one of these is produced in the rectilinear connection section 70a as are the corresponding threaded protrusions 52 in the arc grip part 68b and in the rectilinear connection section 70b so that when screws 54 are inserted into the aligned rear handle protrusions 48 and 52, the rear handle parts 28a and 28b are fixed to one another other for

  form the rear handle 28 and constitute the gripping opening 39.

  As shown in Figures 20 and 21, the rear handle portions 28a and 28b take the form of channels with opposite walls each of which includes a smaller inner wall 72a and 72b and a larger outer wall 74a and 74b and a connecting wall 76a and 76b crossing their respective inner and outer walls 72 and 74 so that when the rear handle parts 28a and 28b are connected, they define a hollow rear handle 28 with the hollow interior space 34 of the rear handle in which the switch housing 36 is mounted. In addition, the interior walls 72a and 72b each include contour portions 80a and 80b along the arc grip portions 68a and 68b so that when the rear handle portions 28a and 28b are connected, the contour portions 80a and 80b contribute to constituting the bottom slot 35 for the actuator pallet 38. When the actuator pallet 38 is mounted in the hollow interior space 34 of the rear handle, the actuator pallet 38 includes a part which extends through the bottom slot 35 in the rear grip opening 39 urged by

  a spring at a predetermined distance beyond the interior wall 72.

  The configuration of the adjacent cord locking mechanism 44

  to the collar region 40 will now be described by

  reference to FIGS. 7 to 9, 20 and 21. As mentioned previously, the cord locking mechanism 44 is disposed at the rear of the collar region 40 in the form of a raised wedge and includes a hollow or the surface of a well 82 constituted by recessed U-shaped surfaces 82a and 82b in the parts of the top of the respective main housing 30a and 30b, as clearly shown in FIGS. 8A and 8B. A straight flange 84 extends from the bottom of the recessed portion 82b to the top of the collar region 40 projecting in a corner with a tab 86 formed above at right angles to the flange 84 and projecting above the recess 82 so that the top of the tab 86 is flush with the top of the corner collar 40. The hollow part 82a is provided with parallel lateral flanges 88 and 90 spaced apart from each other along the two sides of the hollow part 82a and with parts

  constituting overhanging beak 92 and 94 which project towards each other

above the hollow part 82a.

  Thus, when the housing members 18 and 20 are aligned and fixed together, the cord locking mechanism 44 is formed. When the female plug of an electrical cord linked in the collar region 40 to the forks 43 of the connection plug 42, the cord part adjacent to the female plug can be inserted into the zigzag path slot 96 formed by the parts constituting overhanging beak 92 and 94 and the tab 86. The cord portion adjacent to the female plug inserted in the insertion slot 96 can be positioned so as to be fixed between the hollow surface 82 and the overhanging tab 86 positioned at the above the ends of the bead part extending around the straight flange 84 and through access openings 98 and 100 made in the wall part 102 of the recessed surface 82b on both sides of the flange 84 In practice, when the device 10 is in use and the cord is stretched, such as when for example the device is moved away from the electrical power outlet, the voltage created by fixing the cord will be practically absorbed by the friction of the cord between the hollow surface 82 and the overhanging tab 86 and the overhanging parts 92 and 94 so that the interface between the female plug with the male pins 43 will undergo little or no voltage during normal use, which significantly reduces the possibility of accidental disconnection of the interface. On examination of FIGS. 12 and 13, the construction and the operation of the actuator pallet 38 appear, including a locking mechanism 104 which is mounted in close relation thereto. The actuator pallet 38 has the shape of an elongated arc-shaped channel with a low surface 106 having an arc part 107 provided with a radius of curvature practically identical to that of the arc grip part of rear handle 68 and being adapted when gripped by an operator. Two straight parallel side walls 108 and 110 extend along both sides of the bottom wall 106 so that the channel of the arcuate elongated actuator vane 38 opens towards the hollow interior space 34 of

rear handle.

  The elongated actuator pallet 38 has a front end 112 and a rear end 114 and has a pair of pivots forming pivots 116 and 118 each of which extends laterally each from one of the walls 108 and 110 at the front end 112 of the pallet 38. The actuator pallet 38 is mounted in the interior space 34 of the rear handle by means of a pair of corresponding trunnion supports 120 and 122 in the housing members 18 and 20 respectively. The journal supports 120 and 122 are placed adjacent to the well 82 towards the rear of the latter so that when the housing members 18 and 20 are secured, the actuator pallet 38 extends from the base of the well 82 along the curve of the rear handle arc grip portion 68 to the rear end of the contour 80. At the rear end 114 of the actuator pallet 38, a support 124 intended for the locking mechanism 104 is installed. The journals 116 and 1 1 8 being mounted in their respective journal supports 120 and 122, the support 124 extends practically horizontally and is normally urged to engage in a transverse part 126 of the interior wall 172 at the rear of the contour 80. A pair of spring supports 128 and 130 are formed on the bottom surface 106 the front spring support 128 being located on the arc portion 107 of the bottom surface 106 and the spring support 130

  being located on the horizontal support part 124 of the bottom surface 106.

  The actuator pallet 38 is further equipped with an opening 132 produced along its arc portion 107 in the lower surface 106 and the

  walls 108 and 110 to receive the locking mechanism 104 through.

  More specifically, the locking mechanism 104 includes a button 134 and a substantially flat base member 136 extending rearward therefrom. The locking mechanism 104 being assembled in a connection relationship with the actuator pallet 38 and the button 134 projecting through the pallet opening 132, the base 136 extends from a support part 137 formed on the rear part of the arc part 107 adjacent to the rear of the button opening 132 in the channel of the actuator pallet 38 and in the channel of the support part 124 where the base 136 has a curved end 138 which is adapted to engage in a pivot rod 140 fixed to the pallet 38 extending above the walls 108 and 110 in the support part 124. The partition wall 141 extends along the rear of the button 134 and from the flat part of the base 136 and upwards beyond the channel formed by the pallet 38 where it ends on a transverse wall 142 erected from the base 136 the transverse wall 142 extending similarly towards the top beyond the p channel alette 38. At the top of the transverse wall 132, a curved cam surface 144 is produced in order to lock the pallet 138 in a

  closed position, which will be described in more detail below.

  Above the curved end 138 and below the curved cam surface 144, an intermediate spring engaging member 146 extends rearward from the transverse wall 142. A small spring 148 is mounted in compression between the intermediate spring engaging member 146 and the low surface 106 in the support 124 surrounding the spring support 130. In this way, the locking mechanism 104 is normally biased on the pivot rod 140 so that the button 134 extends through opening 132. The rear handle portion 28a includes a spring engaging flange 150 formed in the interior of the rear handle 34 disposed along the contoured portion a of the rear handle 28. A large spring 152 is mounted in compression between the spring engaging flange 1 50 and the base 136 in order to surround the spring support 128 in order to normally stress the actuator pallet 38 in an open position in which the pallet 38 projects from the slot 80 of the rear handle interior wall

  82 in the rear grip opening 39.

  The rear handle portion 28 has ribbed switch support legs 154 and 156 formed in the rear handle interior space 34 along the slit 80 the ribbed legs 154 and 156 framing and supporting both sides of the housing switch 36. The switch housing 36 includes an activation piston 158 (see Figure 11) extending therefrom and the actuator paddle 38 includes a raised trapezoidal flange or actuator member 160 in front of the opening of the opening 132 and of the support 128 adapted to engage the

  activation piston 158 when the pallet 38 is depressed.

  In practice, an operator can easily use one of his hands wrapped around the rear handle 28 to orient the polishing pad 46 adequately on the shaping surface if it is necessary, for example, to perform a sanding, a polishing or equivalent. Due to the rear extension of the rear handle 28 from the main housing 22, below which the pad 46 is mounted, the operator can use the rear handle 28 to reach an extended region of the shaping surface from a relatively fixed position. After adequate orientation of the pad 46 on the shaping surface; the actuator pallet 38 can be pressed in opposition to the bias of the spring in a closed position the pallet 38 pivoting around its journals 116 and 118 and carrying the locking mechanism 104 as well as by engaging the

  support part 137 with the base 136 of the locking mechanism 104.

  When the pallet 38 is thus depressed, the flange 160 engages and likewise depresses the activation piston 158 closing the switching circuit (see FIG. 22) to activate the motor assembly 24 and control the buffer 46

on its orbital path.

  By providing an actuator pallet 38 in an elongated arc which follows the contour of the gripping part in the rear handle arc 68 an operator can grasp the rear handle 28 in different positions on the gripping part 68, while remaining susceptible to push the pallet 38 into its operational position without the need for an operation independent of his other hand and / or before the operator is ready to support and maneuver the

  device 10 by the rear handle 28 during its operation

  this. To deactivate the motor assembly 24, and therefore the device 10, an operator must simply release the pallet 38 which, due to the action of the spring in its open extension position, will deactivate the motor assembly 24 by disengaging the flange 160 of the activation piston 158 for

open the switching circuit.

  Furthermore, if an operator does not wish to continuously depress the pallet 38 during the operation of the device 10, the locking mechanism 104 can be easily accessed and used in a simple manner without interrupting the operation of the device 10 and / or requiring the intervention of the other hand of the operator. As previously indicated, the locking mechanism 104 includes a transverse wall 142 extending into the interior rear handle space 34. In the interior space 34, a locking flange 162 is connected to the exterior wall 74a disposed on the transverse part. of inner wall 126 and comprises a horizontal part 164 and a vertical part 166 connected. In cooperation with the locking flange 162 is a guide flange 168 connected to the outer wall 74a and offset towards

  the front with respect to the vertical part 166.

  The pallet 38 and the locking mechanism 104 are arranged so that when the pallet 38 is pushed into its operational position, the cam end 144 will be positioned near the top of the vertical part 166 between the latter and the guide flange 1 68. In the event of continuous use of the device 10 without the need to continuously depress the pallet 38 in its corresponding operational position, the button member 134 can be pushed towards the interior of the rear handle 34, namely, in the same direction in which the actuator blade 38 is pressed, against the bias of the spring 148, which has the consequence that the outside of the curved cam surface 144 causes by cam effect the guide flange 168 and that it is directed above the top of the vertical part 1 66 of the locking flange 162 and snaps onto the vertical part 166 of the locking flange 1 62 under the effect of the large spring 1 52 while the actuator 38 is held in its closed operating position by the thrust applied by the curved end 138 of the pivot rod 140. To obtain the release of the actuator pallet 38 from its locked position, the operator simply has to push the paddle 38 a little more to limit the effect of the large spring 152 enough to allow the spring 148 to push the curved cam end 144 above the top of the part vertical 166 of the locking flange and against the guide flange 168 as well as the pivoting of the curved end 138 around the pivot rod 140. Then, the pallet 38 is released the spring 150 urging the pallet 38 in its

  open position to deactivate the motor assembly 24.

  To supply electrical power from the connection socket 42 to the motor assembly 24, the switching mechanism 37 includes an input terminal 170 and an output terminal 172 extending through the faces of the switch housing 36 As clearly shown in FIG. 10, a conductor 174 is electrically connected to the connection socket 42 and extends to the input terminal 170 of the switching mechanism while another conductor 176 extends from the output terminal 172 to a full-wave rectifier 178 intended for the direct current motor 24. A conductor 181 is electrically connected to the connection socket 42 and extends directly to the rectifier 178. Conventionally, the rectifier 178 converts the AC power received on the DC connection socket 42 for the DC motor assembly 24. Thus, when the switching circuit is closed under the action when the pallet 38 is pushed into its operational position, a direct current supply is

  supplied to the armature coils, which will be explained in detail here.

  The various components of the engine assembly are supported and oriented directly by the housing shell members 18 and 20 which, when connected, contribute to fixing the engine in its place in the main housing 22 without having to use an external frame as a container for supporting and positioning the various components of the engine and / or a separate base or a chassis element for supporting the frame in the housing. On examining FIGS. 10 and 11, the motor assembly 24 consists of an armature 180 which may be of conventional design, comprising a core and windings 182 aligned around a shaft 184 on which the collector 186 is also located. A steel stator frame 188 in the form of an open cylinder is installed with a pair of large permanent magnets 190 and 192 supported inside the magnets being separated by a space of about 12.7 mm between them at their end in the

built 188.

  A support plate 194 supports the brushes 196 and 198 in respective brush housings 200 and 202 thereof and the rectifier 178 in a housing for rectifier 204 formed inside, as shown in FIGS. 14 and 15. By With reference to FIGS. 10 and 11, the armature shaft 184 has upper and lower ends 206 and 208 provided with a spherical bush 210 mounted on the upper end 206 of the shaft 184 and with a rolling bearing with ball 212 mounted on the shaft 184 to

  near its lower end 208.

  The first and second housing shell members 18 and 20 each include a plurality of generally designated alignment and support members 214 which are symmetrically disposed along a longitudinal axis 216 extending centrally through the main housing 22 The alignment and support members 214 snap into the outer surface 218 of the stator frame 188 and tightly block the bearings 210 and 212 when the housing members 18 and are fixed to each other by so that the stator frame 188 and the armature 180 are aligned along the longitudinal axis 216 the armature shaft 184 extending

  along this and the cylindrical stator frame 188 encircling the armature 180.

  In this way the motor assembly 24 and the housing 16 are assembled with each other in a single operation without requiring a separate assembly operation relating to the motor before it is mounted in the housing. In addition, the motor circuit elements including the switch housing 36, the connection socket 42 and the support plate 194, including the brushes 196 and 198 and the rectifier 178 can be assembled.

  as a sub-assembly before mounting in the housing 16.

  More specifically and with reference to FIGS. 14 and 15, the support plate 194 preferably has a U-shape with opposite rod parts 220 and 222 and a basic transverse part 224 which extends between them and contributes with the parts of rod 220 and 222 to form a central manifold space 226. The support plate 194 is mounted in the housing 16 so that the rod parts 220 and 222 have a space on both sides of the manifold 186 with the manifold 186 positioned in the central space 226. The brush housing 200 is mounted on the rod part 220 and the brush housing 202 is mounted on the rod part 222 at 180 apart from one another around the manifold 186. The brush housings 200 and 202 each including a main body 228 and 230, respectively, having respective brush receiving ports 232 and 234 extending therethrough. The central guide slots 236 and 238 are formed at the top of the main bodies 228 and 230, respectively, the guide slots 236 and 238 communicating with the respective orifices 232 and 234. The brushes 196 and 198 are introduced into their receiving orifices. respective brushes 232 and 234 and have associated conductors 240 and 242, respectively, each of them having respective flat terminals 244 and 246 for electrically connecting brushes 96 and 198

to rectifier 1 78.

  The brushes 1 96 and 1 98 being placed in their holes 232 and 234, and the support plate 194 being mounted in the housing 16 near the manifold 1 86, the brushes 196 and 198 are biased so that at least a portion of these extends into the central space 226 in contact with the external surface 218 of the collector 186. In this way, the brushes 196 and 198 overlap by sliding the external surface of the collector 218 during its rotation around the armature shaft 184 in order to electrically connect the power source to the armature coils. To promote contact of the brushes 196 and 198 with the manifold 186, each of the housings 200 and 202 includes respective linings 248 and 250 and springs 252 and 254. The main body 228 and the main body 230 include enlarged outer ends 256 and 258, respectively. The enlarged outer end 256 includes oblique surfaces 260 and 262 facing each other and extending internally towards the respective right shoulder surfaces 264 and 266. Likewise, the enlarged end 258 includes oblique surfaces facing each other in opposition 268 and 270 extending internally towards the respective right shoulder surfaces 272 and 274. To hang and lock the lining 248 on the main body 228, the lining 248 has a pair of oblique surfaces 276 and 278 extending from both sides of the latter towards the respective right shoulder surfaces 280 and 282. Likewise, the lining 250 is provided with oblique surfaces 284 and 286 extending from the two sides of the latter towards the respective shoulder surfaces 288 and 290. The rear interior surfaces of each of the linings 248 and 250 are equipped with weak spring positioning protrusions

  raised 292 and 294, respectively.

  To assemble the brushes 196 and 198 in their respective housings and 202, the brushes 96 and 198 are inserted in their respective holes 232 and 234 with their conductors 240 and 242 extending from the holes 232 and 234 through slots 236 and 238 of these the flat terminals 244 and 246 are then connected to the appropriate output terminals of the rectifier 178, as described below. To drive the brush 1 96 through the hole 232 of the housing 228 and into the central space 226, the spring 252 is placed in the hole 232 with one end in contact with the brush 1 96 and its other end placed on the protuberance 292 the lining 248 then being pressed closely on the enlarged end 256 of the main body 228 of the housing 200. The lining 248 is pressed tightly on the main body 228 by moving the oblique surfaces 276 and 278 against and along the oblique surfaces 260 and 262 so as to drive the sides of the lining outward as the lining 248 is pushed onto the main body. Once the oblique surfaces pushed one beyond the other, the sides of the lining 248 will return to their original straight configuration, the shoulder surfaces 280 and 282 being in confrontation with the surfaces of respective shoulders 264 and 266 on the main body so as to lock the lining 248 from above. When the lining 248 is locked in place, the spring 252 will act to urge the brush 196 so as to cause it to come out of the central orifice 232 in the central space 226, movement limited by the connection of the conductor 240 with the inner end of the guide slot 236, as clearly shown in FIG. 13. The lining 250 is likewise pressed closely and locked on the main body 230 so as to

  urge the brush 198 through the orifice 234 towards the central space 226.

  In the base part 224 of the support plate 194, the recessed rectifier housing 204 is made. The rectifier housing 204 includes a pair of straight elastic locking members 296 and 298, the locking members 296 and 298 each having an enlarged locking portion 300 and 302 at their respective upper ends. The rectifier 178 has a body portion 304 with a pair of input terminals 306 and 308 and a pair of output terminals 310 and 312 extending from the body portion 304. The rectifier 178 is fixed in the rectifier housing 204 by pushing the part of the rectifier forming a body 304 against the enlarged ends 300 and 302 of the elastic locking members 296 and 298. This results in the driving of the locking members 296 and 298 outwards which thus makes it possible to push the rectifier body part 304 beyond the widened ends 300 and 302 to place it in the housing 204 the elastic locking members 296 and 298 then fixing it by return in a locking position in which the widened ends 300 and 302 adjoin the upper face of the body part 304 in order to trap

  securely the rectifier 178 in the recessed housing 204.

  A pair of conductor guide tongues 314 and 316 leave the support plate 194 practically at the junctions of the part of the support plate foot 224 with the leg parts 220 and 222. The subassembly formed by the connection socket 42, the housing switch 36 and rectifier 178 and brushes 196 and 198 of support plate 194 have electrical conductor connections described below. As anyone skilled in the art will see, various arrangements of conductive wires can be implemented

  with the motor assembly 24 in order to apply its electrical supply thereto.

  Preferably, the conductor 174 is electrically connected to one end of the connection socket 42 and on its other end it has a flat terminal 174a which is electrically connected to the input terminal of the switching mechanism 37. The conductor 176 is provided with a flat terminal 176a integral with the output terminal 172 of the switching mechanism 27 while its other flat terminal 176b at the other end of the conductor 17 is linked to one of the input terminals 306 and 308 of the rectifier 178. The conductor 181 is electrically connected to one end of the connection socket 42 and at its other end has a flat terminal 181a which is linked to the other end of the rectifier input terminals 306 and 308. The brush conductors 240 and 242 are each electrically connected to one of the input terminals 310 and 312 preferably with the flat terminal 244 connected to the output terminal 310 and the flat terminal 246 connected to the output terminal 312, as shown in FIG. 14. To insulate the non-insulated braided conductor wire 242 from other similar non-insulated braided conductors, the conductor wire 242 extends from the guide slot 238 around the guide tab of conductor 316 and to the output terminal 312. As it appears clearly, the conductor guide tabs 314 and 316 can be used to guide the conductor wires connected to the terminals of the rectifier in different ways so as to avoid the wires uninsulated conductors

  to get in touch with each other.

  For mounting the rectifier and the brush support plate 194 in the interior space of the housing 56, recesses constituting shoulders 318 and 320 are made along the outer edges of the support plate rod portions 220 and 222, respectively. On examining FIGS. 11 and 20, the support and alignment members 214 of the housing member 18 comprise a pair of vertical notched ribs 322a and 324a each of the vertical ribs comprising a juxtaposition member 326a and 328a extending laterally from the notched area to the housing member 18. The vertical ribs 322a and 324a are spaced laterally from one another in the interior space portion of the housing 56a the spacing corresponding to the distance between the shoulders of support plate 318 and 320 so as to receive flush with the shoulders of support plate 318 and 320 in the notches of vertical rib against the juxtaposition elements 326a and 328a when the plate 194 is mounted in the housing member 18. When the support plate 194 is thus mounted, the longitudinal axis

  216 extends through the central space of support plate 226.

  To fix the support plate 194 in the interior space of housing 56, the corresponding notched vertical ribs 322b and 324b are produced in the housing member 20 (see FIG. 21) their notches being aligned vertically with the notches of the vertical ribs 322a and 324a when the housing members 18 and 20 are connected. The notched vertical ribs 322b and 324b snap into the ends 334 and 336 of the support plate rod portions 220 and 222 projecting beyond the respective brush housing 228 and 230 so as to prevent movement of the plate support 194 in space

housing interior 56.

  To mount the armature 180 in the interior space of the housing 56, the armature shaft 184 being aligned along the longitudinal axis 216, the alignment and support members 214 include upper and lower bearing engagement members. 338a and 340a in the housing member 18 and upper and lower bearing engagement members 338b and 340b in the housing member 20 which contribute to the constitution of upper and lower pockets in the interior space of the housing 56 the axis longitudinal 216 extending through these pockets. These pockets formed by the bearing engagement members 338 and 340 are configured so as to securely trap the respective upper and lower bearings 210 and 212 to avoid movement in space.

housing interior 56.

  More specifically, since the upper bearing 210 is preferably a spherical bearing, the upper bearing locking member 338 is produced using a pair of curved side walls 342 and 344 the radius of curvature of the side walls 342 and 344 corresponding practically to that of the spherical bearing 210. In this way, the movement of the spherical bearing 210 along the longitudinal axis is avoided by its imprisonment in the upper bearing latching member 338 in the interior housing space 56. In addition, the curved side walls 342 and 344 are connected by upper and lower horizontal members 346 and 348 the upper and lower members 346 and 348 being curved at their ends adjacent to the longitudinal axis 216. Extending between the walls curved side 342 and 344 in an intermediate position between the upper and lower limbs 346 and 348 is a support rib t horizontal 349 having a curved end which does not extend as far towards the axis 216 as the ends of the upper and lower members 346 and 348 to adapt in correspondence with the shape of the spherical bearing 210. Thus, the diameter according to the curved ends of the intermediate support ribs 349a and 349b in each of the housing members 18 and 20 when they are integral is practically the same as the largest diameter passing through the middle of the spherical bearing 210. Similarly, the diameter according to the curved ends of the horizontal upper and lower members 346 and 348 corresponds practically to the smallest diameter between the top and the bottom of the spherical bearing 210 so as to avoid the movement of the latter in a lateral direction when it is fixed and trapped in the interior space of

housing 56.

  The lower bearing latching member 340 is similarly constructed to the upper bearing latching member 338 except that it is configured to capture the lower bearing 212 which preferably takes the form of an annular bearing ball. The lower bearing engagement member 340 is therefore provided with a pair of spaced straight side walls 350 and 352. The side walls 350 and 352 are interconnected by horizontal upper and lower members 354 and 356 these upper and lower members 354 and 356 having curved ends which terminate in straight end portions extending to the respective vertices and lower parts of the side walls 350 and 352. The housing members 18 and 20 being integral, the curved ends of the upper and lower members 354a and 354b and 356a and 356b define a diameter slightly smaller than the outside diameter of the annular bearing 21 2. Thus, when the annular bearing 212 is fixed and mounted in the lower bearing latching member 340, the upper and lower members 354 and 356 prevent the bottom annular bearing

  212 to move on its axis along the longitudinal axis 216.

  By extension between the side walls 350 and 352 in an intermediate position to the upper and lower members 354 and 356 is a horizontal support rib 358 provided with a curved end ending in the side walls 350 and 352 so that when the housing members 18 and 20 are integral, the horizontal support rib parts 358a and 358b of each of the housing members have a diameter according to their curved ends corresponding to the outside diameter of the annular bearing 212 so as to trap it and prevent its movement according to a lateral direction in the interior housing space 56. Thus, the armature shaft 184 being mounted so as to be able to rotate in the upper spherical bearing 210 and the lower annular bearing 212 and the bearings 210 and 212 being fixed in the space housing interior 56 in the pockets formed by the bearing engagement members 338 and 340, the armature 180 thus that its manifold 186 are aligned in rotation on the shaft 184

  extending along the longitudinal axis 216.

  The cylindrical stator frame 188 is mounted in the interior housing space 56 so as to circumscribe the core and the windings 182 in alignment about the longitudinal axis 216. To mount the cylindrical stator frame 188 in alignment around the axis 216, the alignment and support members 214 include horizontal arch reinforcements 360, spaced vertically in the housing members 18 and 20, as clearly shown in FIGS. 20 and 21. The vertical reinforcing ribs 362 connect the pairs reinforcements in arc with vertical spacing. The reinforcements 360 include upper arch reinforcements 364 and horizontal lower arch reinforcements 366 which extend horizontally slightly further towards the axis 216 than the other arch reinforcements 360 located between them so that when the members of housing 18 and 20 are integral, the upper aligned reinforcements 364a and 364b of the respective housing members 18 and 20 and the lower aligned reinforcements 366a and 366b of the respective housing members 18 and 20 contribute to defining a diameter slightly smaller than the diameter depending on the surface exterior of the frame 218. In this way, the upper reinforcements 364 extend above the upper end surface 368 of the frame 188 and the lower reinforcements 366 extend below the lower end surface of the frame 188 so that the frame is tightly trapped between the upper and lower reinforcements 364 and 366 to oppose the movement according to the longitudinal axis 216. To trap the frame 188 by preventing any lateral movement in the interior space 56, the intermediate arc reinforcements 360 have a radius of curvature corresponding practically to the radius of curvature of the cylindrical frame 188 so that together the 360 arc reinforcements define a diameter practically identical to the diameter of the exterior surface of the frame. As indicated above, the housing members 18 and 20 are preferably made of molded plastic and the alignment and support members 214 including the horizontal reinforcements 360 are preferably made entirely of this material. In this way, the arcuate ends of the plastic reinforcements 360 can snap into place on the outer surface 218 of the frame 188 when the housing members 18 and 20 are connected to each other so as to fix the frame 188 in the interior space 56 in alignment around the longitudinal axis 216 and in wrapping relation with the core of the armature and the windings 182 the force necessary for the fixing being exerted by the

  force due to the insertion of the screws 254 into the aligned protrusions 48 and 52.

  The mounting of the components of the DC motor directly on the housing members 18 and 20 under the effect of the fixing of these represents a cost saving for the manufacture of the device because the assembly of the motor assembly 24 is no longer the subject of a separate assembly operation and can on the contrary be integrated during the same manufacturing operation in the device 10. In addition, the shape of the motor assembly 24 must not necessarily adopt that of a "container" for the frame 188 which would require an extension of the frame comprising fittings and bearing plates to close the cylindrical ends, no more than the motor assembly 24 does not require a base or an independent chassis for mount the "container" of the engine on it. The rectifier is normally mounted in a position adjacent to the "container" of the motor, as well as on the motor chassis, providing for the passage of the conductors of the motor brushes through the motor housing in order to connect them electrically to the rectifier. outside the engine housing. Thus, cost savings can be obtained by reducing the time required for assembly as well as by eliminating the parts associated with an engine comprising a "container" and providing an uninterrupted path of the

  conductors between the brushes and the rectifier.

  As indicated above, the device 10 preferably allows the mounting of a pad 46 for sanding, waxing, polishing or the like. In this form, the housing 16 can be equipped with a sheath 372 formed in its lower part, the sheath 372 having an annular part 374 extending outwards from the lower part 32 of the main housing part 22 aligned on the longitudinal axis 216. Linked to the annular part 374 is a skirt of circumference 376 from which the

  polishing pad 46 can project.

  To allow stable movement of the polishing pad 46 on its orbital path during its actuation, a counterweight assembly 378 is provided. The counterweight assembly 378 includes a buffer mounting upright 380 implanted thereon to allow a

  rapid mounting and dismounting of the buffer 46 on the device 10.

  More specifically and with reference to Figures 16-19, the counterweight assembly 378 includes a flat raised mounting portion 382 and a lower counterweight portion 384 offset from the raised mounting portion 382. The raised mounting portion 382 includes an opening threaded 386 passing through it intended to receive the threaded end 208 of the armature shaft 184 projecting through the annular ball bearing 212. Thus, the threaded end 208 of the armature shaft being in the opening, the set of

  counterweight 378 is mounted on the device 10 to rotate with the shaft 1 84.

  The quick change pad mounting post 380 is connected to raised mounting portions 382 adjacent to the threaded opening 386 and allows the polishing pad 46 to be mounted such that rotation of the counterweight assembly 378 due to the connection with the armature shaft 184 in the opening 386 produces an almost circular orbital path according to which the pad 46 moves around the shaft 184 and therefore, around the longitudinal axis 216. Because the amount mounting 380 will be aligned with the center of the buffer 46 as described and that the shaft 1 84 is located between the upright 380 and the counterweight portion 384, during the rotation of the counterweight assembly 378, the portion counterweight 384 will always be located above the smallest part of the buffer constituted by a line of rope drawn so as to pass through the circular buffer 46 through the shaft 184 and by the width of the counterweight assembly 378. From this In this way, the counterweight part 384 acts in opposition to the forces generated during the rotation of the tampon 46 on its orbital path which in its absence would tend to destabilize the device 10. The tampon 46 responds to a conventional manufacturing method and, under a preferred form has a diameter of 22.8 cm. The pad 46 has a plastic pad mounting plate 388 bonded to its upper surface. Projecting outward from the center of the pad mounting plate 388 is an annular post receiving member 390 having a central port 392 extending therethrough in alignment with the axis port central pad 46. The central hole 392 can be provided with a shaft sleeve 394 fixed inside with a shaft lining 396 mounted to be able to rotate in the shaft sleeve 394

  as well as bearings (not shown).

  The upright 380 has a recess 398 machined near the bottom end 400 of the upright 380. To allow reversibility of the mounting of the pad on the mounting post of quick-change pad 380, a retaining ball 402 linked to a plastic support 404, in polyurethane for example, is fixed in the recess 398. The recess 398 has an opening diameter slightly larger than the diameter of the retaining ball 402 so that the retaining ball 402 is introduced by slip into withdrawal 398 when linked to it. The ball 402 being linked to the withdrawal 398 by means of the plastic support 404, the ball 402 protrudes a certain distance beyond the surface of the upright 380 in an extended position. When the ball 402 is mounted on the plastic support 404, the ball 402 can be pressed by exerting a force on the ball 402 which compresses the plastic support so that the ball is flush with the

upright area 380.

  To move the ball 402 in its depressed position, the shaft lining 396 has a diameter practically identical to the diameter of the buffer mounting upright 380 so that the insertion of the upright 380 in the lining 396 causes the initial engagement of the lower curved surface part 406 of the ball 402 in the upper annular end 405 of the sleeve 394. A continuous force exerted downwards on the counterweight assembly 398, and therefore on the upright 380, causes a cam effect of the shaft lining 396 on the curved surface portion 406 by application of a force directed inwards in order to move the ball 402 radially inwards in a position flush with the surface of the upright

  opposition to the stress on the plastic support 404.

  When the ball 402 is in a sunken position relative to the upright 380, the upright 380 can be easily pushed into the shaft sleeve 394 until the bottom 408 of the raised mounting part rests against the top 410 of the raised annular member 390 the counterweight portion 384 being adjacent thereto. Thus, the upright 380 being inserted through the lining 394, the pad 46 is in a reversible fixing state, the lower end 400 extends beyond the shaft lining 396 so that the ball 402 does not does not remain engaged with the shaft lining 396. Consequently, the predetermined force applied to the curved surface part 406 is no longer applied therein so as to allow the retaining ball 402 to rebound under the effect of the support in plastic 404 in its extended position beyond the radius of the upright 380. The ball 402 is mounted on the upright 380 at a predetermined distance from the bottom 408 of the raised mounting part 382 and the length of the shaft sleeve 394 is also predetermined so that when the pad 46 is reversibly fixed to the upright 408 and the ball 402 is in its extended position, the upper curved surface portion 412 comes to abut the lower annular end eure or shoulder 414 of the axle sleeve so that there is no more empty space or play between the receiving member of raised upright 390 and

The counterweight assembly 308.

  When the pad 46 is mounted on the quick change pad mounting post 380 with the holding ball 402 on it and when an operator wishes to change the pad to switch to a pad of another type or because the pad 46 requires replacement due to wear, deterioration or the like, the pad 46 can quickly and easily be removed from the device 10 without consequent delay or

  disassembly likely to complicate the buffer change operation.

  To disassemble the pad 46, an operator simply has to exert a downward force away from the pad mounting post 380 on the pad mounting plate 388 sufficient to cause the cam effect of the low annular shoulder of seal 414 on the upper curved surface part 412 so as to bring the ball 402 in its sunken position level with the surface of the upright against the normal stress of the plastic support 404. The ball 402 being in its position pressed down, a continuous downward force exerted on the pad mounting plate 388 causes the packing 396 to slide from the upright 380 until the pad mounting plate 388 and the pad 46 which is

  linked to it are separated from the amount 380.

  Although the ball 402 and the pad mounting post 380 constitute a reliable mounting of the pad 46 on the device 10, it is possible that during the use of the device 10, sufficient force to cause the movement of the ball holding 402 in its depressed position is applied to the pad 46 and / or to the pad mounting plate 388. In this case, the shaft lining 396 has an intermediate groove with a circumference 416, spaced above the ball of hold 402 to prevent the complete sliding of the upright 380 at

  across the shaft sleeve 394 to the disengaged position.

  The circumference groove 416 has a predetermined radius dimensioned so as to make it suitable for capturing the retaining ball 402 in an extended position in which it protrudes beyond the surface of the upright 380 when it passes above. Thus, the pad 46 being mounted on the upright 380 and an involuntary force being applied to the pad mounting plate 388 or the fixed pad 46 causing the ball 402 to move towards its position inserted in the shaft lining 396, a prolonged movement of the upright 380 through the trim

  axis 396 will eventually bring the ball 402 into contact with the groove 416.

  The stress on the plastic support 404 will push the ball 402 into an extension position in the circumference groove 416 and therefore stop the continuous movement of the upright 380 in the jacket 394 so as to allow an operation offering practically total safety of the device. 10 when the buffer 46 is fixed to the mounting post of

buffer 380.

  Although various characteristics of the use of an electric polishing or encircling apparatus have been illustrated and described, it is possible to implement these characteristics with other tools. In addition, it is clear that many variations and modifications will appear

  to those skilled in the art, and the appended claims

  clearly cover all of these variations and modifications which fall within the spirit and true scope of the present invention.

Claims (12)

  A motor tool comprising: a main housing (22) containing a motor (24) for controlling a shaping element; a hollow handle (28) connected to the housing; an actuator pallet (38) mounted so as to be able to pivot relative to the handle (28) and able to pivot between (1) an open position in which the motor (24) is deactivated, and (2) a closed position in which the motor (24) is activated to control the shaping element and the pallet (38) being in the closed position the release of the pallet (38) causes the pallet (38) to return to the open position to deactivate the motor ( 24); and a locking member (104) mounted on the pallet (38) to be movable therewith whereby when the pallet (38) is in the closed position the member (104) is capable of holding the pallet (38 )   in the closed position when the pallet (38) is released.   2. Power tool according to claim 1 wherein the handle (28) has an elongated, arcuate shape and extends away from the housing (22) and the pallet (38) has an elongated arcuate shape substantially in accordance with the shape of the handle (28) the handle (28) including a pallet receiving slot (35) along the length thereof, the pallet (38) being mounted on the handle so as to project from of the slot (35) and allowing the pallet (38) to be pushed into the slot (35) when it   is set in motion from the open position to the closed position.   3. A power tool according to claim 1, wherein the pallet (38) includes an opening (132) with the locking member (104) including a button portion (134) projecting through the opening of   pallet (132) and a cam portion (144) in the hollow handle (28).   4. A power tool according to claim 3 wherein a flange (162) is mounted in the hollow handle (28) and when the pallet (38) is moved into the closed position the member forming a button (134) can be pushed into the pallet opening (132) to drive the cam portion (144) to trigger the flange (162) and hold the pallet (38) in its   closed position when the pallet (38) is released.   5. A motor tool according to claim 1, in which the handle 28 includes a switching means (37) mounted inside intended to activate the motor (24) and the vane (38) includes an actuating member with the vane ( 38) mounted in the handle (28) so that in the open position the actuator member is spaced from the switching means (37) and the motor (24) is deactivated and in the closed position the actuator member engages   the switching means (37) for activating the motor.   6. A power tool according to claim 1 further including a cam means (144) contributing with the handle (28) and the locking member (104) to move the locking member (104) between (1) a non-position locked in which the pallet (38) is freely movable between its open and closed positions, and (2) a locked position in   which the pallet (38) is held in the locked position.   7. A power tool according to claim 6 wherein the handle (28) includes a flange (162) mounted therein and the locking member (104) includes a portion extending inside the handle (28) , the cam means includes a cam surface (144) on at least one of the two flange (162) and locking member (104) members which allows the portion to release the flange (162) when the locking member is   moved from the unlocked position to the locked position.   8. A power tool according to claim 1 wherein the pallet (38) has a length and spaced ends and the locking member (104) is mounted to be able to pivot at one end of the pallet (38) and the pallet (38 ) is mounted so that it can pivot in the housing (22) to the other end of the pallet (38).   9. A motor tool comprising a housing (22) containing a motor (24) for controlling a shaping element; a handle (28) connected to the housing; an actuator pallet (38) mounted so as to be able to pivot relative to the handle (28) in which the movement of the handle (28) in its operational position in a first direction causes the control of the shaping element by the motor ( 24); and a locking member (104) mounted to pivot relative to the pallet (38) in which movement of the locking member (104) in the first direction is capable of locking the   pallet (38) in its operational position.   10. A power tool according to claim 9 wherein the handle (28) has a hollow interior (34) and includes a slot (35) and the pallet (38) is mounted in the slot (35) the pallet can be pushed into the slot (35) in the first direction towards the inside of the handle (28) to   be moved accordingly to its operational position.   11. A power tool according to claim 9 wherein the handle (28) has a hollow interior and the pallet (38) and the locking member (104) can be both pushed in the first direction inward. interior of the handle (28) to consequently maintain the pallet (38) in its operational position and easily allow setting tool work with one hand.   12. A motor tool provided with a shaping element controlled by an electric motor, the motor tool comprising a housing (22); a hollow handle (28) connected to the housing (22); switching means (37) in the handle (28) electrically connected to the motor (24) and having active and inactive states so that when the switching means (37) is in the active state the motor (24 ) is activated in order to control the shaping element and in the inactive state the motor (24) is deactivated; an actuator pallet (38) mounted to allow movement relative to the handle (28) between (1) an extended position in which the actuator extends a first distance from the handle (28) and the means switch (37) is in the deactivated state, and (2) a first depressed position in which the actuator extends at a distance from the handle (28) less than the first distance and the switching means is in the 'state activated; and a locking member (104) carried by the pallet actuator (38) capable of being pressed with the pallet (38) in the first pressed position to lock the pallet (38) in the first pressed position so that when the pallet is in the first locked, depressed position, the pallet (38) can be pressed in a second depressed position in which the actuator extends at a third distance from the handle (28) less than the second distance to release the locking member (104) and the pallet (38) from the locked pallet position and allow movement of the pallet (38) in its extended position when the pallet is released.   i 3. A power tool according to claim 12 wherein the actuator includes an opening and the locking member (104) includes a member   forming a button (134) extending through the opening.   i14. The power tool of claim 13 wherein a locking flange (162) is mounted in the hollow handle (28) and the locking member (104) includes a cam member (144) in the hollow handle (28) disposed such that the pallet (38) being in its first depressed position the button member (134) can be pressed into the pallet opening to cause the cam member (144) to apply a cam effect on the flange ( 162) and to trigger it and keep the pallet in the first position pressed when the pallet is released.