Abstract:
The invention relates to a remote controller for heavy construction machines with a body, comprising a cavity, running between a first outlet end and a base, a first pushrod, running between a head and a base, arranged to slide with a back and forth movement in the cavity along an axial direction, a handle which may pivot with relation to the body, whereby a skirt of said handle is in direct contact with the head. The first pushrod may furthermore be moved to an extended position opposite to the depressed position with relation to the idle position thereof. First elastic return means are arranged in the cavity to force the pushrod into the extended position thereof and detection means are provided to detect the position of the first pushrod.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to the technical field of remote controls for heavy construction machines, particularly remote controls of the electrohydraulic type. 
   The invention relates more specifically to remote controls intended to control one or more receivers, particularly users of pressurized fluid, from a handle manipulated by the operator in order to transmit a control signal to said hydraulic receivers. 
   The remote controls customarily encountered on heavy construction machinery comprise:
         a body which comprises at least one cavity running between an open end opening onto at least a top face of the body and a bottom at the opposite end to the open end,   at least one first pushrod which runs between a head end and a foot end, which is mounted to slide back and forth in said at least one cavity of the body in an axial direction between a rest position and a depressed position, and which is intended to control at least a first receiver external to the remote control, and   a handle which comprises a transverse skirt and which is mounted to pivot with respect to the body opposite the top face of said body to control the back and forth movement of said first pushrod, the skirt simply resting against the head end of said pushrod, and the axis of the handle making a variable acute angle with the axis of the pushrod.       

   Even though such remote controls allow the movements of receivers to be controlled satisfactorily, they do require numerous component parts in as much as they have to have several pushrods each equipped with detection means to detect the position occupied by each of the pushrods between their rest position and their depressed position. The cost of such remote controls is therefore high and their reliability may be adversely affected by one of the numerous component parts. 
   SUMMARY 
   It is therefore an object of the present invention to remedy the aforementioned disadvantages by providing a remote control in which the number of component parts is reduced while at the same time maintaining the same functionalities. To this end, according to the present invention, the remote control of the aforementioned type is essentially characterized in that at least the head end of the first pushrod can also move toward a protruding position which is on the opposite side of said rest position to the depressed position, in that first elastic return means urge the head end of the pushrod toward its protruding position so that at least the head end of the first pushrod has an autonomous upward movement, and in that the remote control further comprises detection means for detecting the position occupied by the head end of the first pushrod between its protruding and depressed positions. 
   Thus, by virtue of these measures, the number of pushrods equipped with detection means is reduced because just one pushrod is needed rather than the two pushrods present in remote controls of the prior art. 
   Advantageously, the detection means are of the type free of mechanical contact. 
   As a preference, the detection means comprise a magnet which moves as one with the head end of the pushrod. 
   According to one possibility, the cavity is stepped and comprises a first shoulder more or less transverse to the movement of the first pushrod, and said pushrod comprises an intermediate portion which moves as one with the head end and the foot end of the pushrod and is located between its head end and its foot end and delimits a top stop and a bottom stop, the top stop coming to rest against the first shoulder when the pushrod is in the protruding position and the bottom stop coming to rest against the bottom of the cavity when said pushrod is in the depressed position. 
   As a preference, the first return means are housed in the cavity. 
   Again as a preference, the first return means comprise a collar borne by the intermediate portion near the top stop and a first compression spring inserted between the collar and the bottom of the cavity. 
   According to another possibility, the cavity comprises a shoulder substantially transverse to the movement of the first pushrod, and said pushrod comprises a head end and a foot end that move together as one and are able to move translationally along the axis of the pushrod with respect to an intermediate portion which is situated between the head end and the foot end and delimits a top stop and a bottom stop, the top stop coming to rest against the shoulder when the head end of the pushrod is between its rest position and its protruding position and the bottom stop coming to rest against the bottom of the cavity when said pushrod is in the depressed position. 
   For preference, the first elastic return means are housed between the head end of the pushrod and the intermediate portion of the pushrod. 
   According to one embodiment, the first elastic return means comprise a first compression spring inserted between the head end of the pushrod and the intermediate portion of the pushrod. 
   Advantageously, second elastic return means are housed in the cavity to return the first pushrod from its depressed position to its rest position. 
   According to one possibility, the second return means comprise a ring concentric with the first pushrod, a second compression spring inserted between the ring and the bottom of the cavity, and a peripheral relief moving as one with the first pushrod and intended to come to rest against the ring, the cavity further comprising a second shoulder against which the ring abuts when the first pushrod is in the rest position. 
   According to another possibility, the second return means comprise a collar borne by the intermediate portion near the top stop and a second compression spring inserted between the collar and the bottom of the cavity. 
   Advantageously, a second pushrod is mounted in a second cavity of the body, the second pushrod being elastically urged by a third compression spring in such a way that the force that has to be exerted on the handle in order to depress one of the first and second pushrods is substantially constant. 
   According to one embodiment, the second cavity is symmetric with the first cavity with respect to the axis of the handle in the rest position. 
   Advantageously, at least the head end of the second pushrod is able to move toward a protruding position which is on the opposite side of said rest position to the depressed position and elastic return means urge the head end of the pushrod toward its protruding position so that at least the head end of the second pushrod has an autonomous upward movement. 
   According to one embodiment, the foot end of the first pushrod is mounted such that it passes through the bottom of the cavity and internally bears the magnet. 
   Advantageously, a Hall-effect sensor is mounted in the body of the remote control facing the movement of the magnet between the depressed and protruding positions of the first pushrod is depressed and protruding. 
   According to one embodiment, the second pushrod is located on the opposite side of the axis of the handle to the first pushrod. 
   Advantageously, the Hall-effect sensor is potted in resin so that it is situated in a sealed location. 
   In any event, the invention will be clearly understood with the aid of the description which follows, with reference to the attached schematic drawing which, by way of nonlimiting example, depicts three embodiments of the remote control according to the present invention. 

   
     BRRIEF DESCRPTJON OF THE DRAWINGS 
       FIG. 1  is a view in longitudinal section of the remote control according to a first embodiment. 
       FIG. 2  is an enlarged view of the first pushrod of  FIG. 1 . 
       FIGS. 3 and 4  are views similar to those of  FIGS. 1 and 2 , the handle having been pivoted to move the first pushrod into its depressed position. 
       FIGS. 5 and 6  are views similar to those of  FIGS. 1 and 2 , the handle having been pivoted toward the opposite position to allow the first pushrod to move into its protruding position. 
       FIG. 7  is a view in longitudinal section of the remote control according to a second embodiment. 
       FIG. 8  is a view similar to that of  FIG. 7 , the handle having been pivoted to move the first pushrod into its depressed position. 
       FIG. 9  is a view similar to that of  FIG. 7 , the handle having been pivoted to the opposite position to allow the head end of the first pushrod to move into its protruding position. 
       FIG. 10  is a view in longitudinal section of the remote control according to a third embodiment. 
       FIG. 11  is a view similar to that of  FIG. 10 , the handle having been pivoted to move the first pushrod into its depressed position. 
       FIG. 12  is a view similar to that of  FIG. 10 , the handle having been pivoted into the opposite position to allow the head end of the first pushrod to move into its protruding position. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     FIG. 1  depicts a remote control  1  for heavy construction machines which comprises, in a way known per se, a body  2 , at least one first pushrod  3  which is mounted to slide in the body  2  and a handle  4  which is mounted to pivot with respect to this body to control the back and forth movements of the first pushrod  3  inside the body  2 . 
   The first pushrod  3  is mounted to slide inside a first cavity  5  which runs between an open end  6  opening onto at least a top face  7  of the body  2  and a bottom  8  at the opposite end to this open end  6 . 
   The body  2  has a longitudinal axis X-X and the first pushrod  3  slides parallel to this axis X-X. 
   The handle  4  is mounted so that it can pivot with respect to the body  2 , facing the top face  7  of this body, to control the back and forth movements of said first pushrod  3 . This handle  4  has an axis Y-Y and possesses a transverse skirt  10  which allows said at least one first pushrod  3 , to be controlled. The axis Y-Y of the handle  4  forms a variable acute angle with the axis of the pushrod  3  which angle is dependent on the position to be given to the pushrod. When the handle  4  is in the rest position, it runs along the axis X-X of the body  2  as depicted in  FIGS. 1 and 2 . The positions of the handle depicted in  FIGS. 3 and 5  allow said first pushrod  3  to be commanded into its depressed position and into its protruding position, respectively. 
   To this end, said pushrod  3  runs between a head end  12  and a foot end  13 . The head end  12  is mounted so that it can move back and forth at the open end  6  of the body  2  so that the skirt  10  of the handle  4  simply rests on this head end  12 . The foot end  13  of the pushrod  3  is housed in the bottom  8  of the cavity  5  to control at least a first receiver external to the remote control. 
   The head end  12  of the first pushrod  3  abuts against the underside of the skirt  10  of the handle  4  and is commanded between its rest position as depicted in  FIGS. 1 and 2  and its depressed position as depicted in  FIGS. 3 and 4  in a way well known in the state of the art. 
   According to an essential feature of the present invention, this first pushrod  3  can also move into a protruding position as depicted in  FIGS. 5 and 6 , this protruding position being on the opposite side of the rest position to the depressed position. 
   To do this, the remote control according to the present invention has first elastic return means  15  which are housed in the cavity  5  to urge the first pushrod  3  into its protruding position so that this pushrod has its own inherent upward movement. During this upward movement, the handle  4  is pivoted in such a way as to disengage the head end  12  of the pushrod  3  so that this head end  12  has an upward movement to follow the skirt  10  simply under the action of the first elastic return means  15 . 
   Furthermore, in order to control said first external receiver, the remote control  1  further comprises detection means  17  to detect any position occupied by this first pushrod  3  between its protruding and depressed positions. 
   As a preference, the cavity  5  is stepped and comprises a first shoulder  20  situated under the open end  6  and running substantially transversely to the movement of the first pushrod  3 , that is to say more or less at right angles to the axis X-X. Furthermore, the pushrod  3  has an intermediate portion  22  which is of larger diameter than the head end  12  and the foot end  13  of this pushrod and is installed along the length of said pushrod. In this embodiment, the head end  12 , the foot end  13  and the intermediate portion  22  move as one. This intermediate portion thus has a top face  23  which delimits a top stop and a bottom face  24  which delimits a bottom stop. The top face  23  faces toward the first shoulder  20  while the bottom face  24  faces toward the bottom  8  of the cavity  5 . 
   Thus, as the pushrod  3  moves back and forth inside this cavity  5 , the top stop  23  is intended to come to rest against the first shoulder  20  as depicted in  FIGS. 5 and 6  to define the protruding position of this pushrod  3  while the bottom stop  24  is intended to come to rest against the bottom  8  of this cavity when the pushrod is in the depressed position as depicted in  FIGS. 3 and 4 . 
   The first return means  15  preferably comprise a collar  26  borne by the intermediate portion  22  near the top stop  23 , this collar facing toward the bottom  8  of the cavity  5 . The first elastic return means  15  also comprise a first compression spring  27  inserted between the collar  26  and the bottom  8  of the cavity  5 . This compression spring  27  has a diameter slightly greater than that of the intermediate portion  22  so that it can be pushed onto this portion until it reaches the collar  26 . 
   Thus, the first pushrod  3  has an upward movement imposed on it by the first compression spring  27  so that when the head end  12  of this pushrod  3  is disengaged by the skirt  10  of the handle  4 , the pushrod  3  has an upward movement into its protruding position by virtue of the compression means  27 . 
   Furthermore, according to another feature of the invention, the remote control  1  has second elastic return means  30  housed in the cavity  5  to return this first pushrod  3  from its depressed position as depicted in  FIGS. 3 and 4  to its rest position as depicted in  FIGS. 1 and 2 . 
   As shown more particularly by  FIGS. 3 and 4 , the second elastic return means  30  comprise a ring  31  concentric to the first pushrod  3 , a second compression spring  32  inserted between the ring  31  and the bottom  8  of the cavity  5 , and a peripheral relief  33  which moves as one with the first pushrod  3  and is intended to come to rest against the ring  31 . Furthermore, the cavity  5  has a second shoulder  35  situated at a level somewhere between the first shoulder  20  and the bottom  8  of the cavity  5 . The second compression spring  32  urges the ring  31  toward the second shoulder  35  so that this ring  31  comes into abutment against this second shoulder when the first pushrod  3  is in its rest position as depicted in  FIGS. 1 and 2 . The second shoulder  35  thus somewhat defines the rest position of the pushrod  3 . 
   The pushrod  3  is thus in equilibrium in its rest position between the action exerted by the skirt  10  on the head end  12 , which tends to depress the pushrod  3 , and the action of the first compression spring and of the second compression spring  27  and  32 . In this rest position, the ring  31  is in abutment against the second shoulder  35  while the peripheral relief  33  is in abutment against this ring  31  under the action of the handle  4 . 
   When the pushrod  3  is in its depressed position as depicted in  FIGS. 3 and 4 , the skirt  10  of the handle  4  urges the head end  12  of the pushrod  3  downward so that the intermediate portion  22  drives the concentric ring  31  in a downward movement and compresses the compression springs  27  and  32  until this intermediate portion  22  comes into abutment downward against the bottom  8  of the cavity  5 . 
   Conversely, when the pushrod  3  is in its protruding position as depicted in  FIGS. 5 and 6 , the head end  12  of this pushrod has been disengaged by the skirt  10  of the handle  4  so that the intermediate portion  22  has come into abutment upward against the first shoulder  20  under the action of the first compression spring  27 . During the return movement from the depressed position to the protruding position the compression springs  27  and  32  relax. The concentric ring  31  comes into abutment against the second shoulder  35  of the cavity  5  while the peripheral relief  33  is no longer in contact with the ring  31  when the pushrod moves from its rest position to its protruding position. 
   The pushrod  3  occupies any position between its depressed position and its protruding position according to the inclination given to the handle  4 . 
   The foot end  13  of the pushrod  3  extends beyond the bottom  8  of the cavity  5  so that it passes through this bottom in a back and forth movement between its protruding and depressed positions. 
   As a preference, the detection means  17  are of the type free of mechanical contact and for example comprise a magnet  40  that moves as one with the pushrod  3  by being mounted inside the foot end  13  of this pushrod, together with a Hall-effect sensor  41  which is mounted in the body  2  of the remote control  1 , facing the movement of the magnet  40  between the depressed and protruding positions of the first pushrod  3 . More specifically, the Hall-effect sensor  41  is mounted in the body  2  beyond the bottom  8  of the cavity  5 . Thus, this sensor  41  can be potted in a substance such as resin in order to seal it. 
   Furthermore, even though this first pushrod  3  is able by itself to control a first receiver, a second pushrod  50  is installed in the body  2  of the remote control  1  in order to balance the handle  4 . This second pushrod  50  is a passive pushrod in as much as it is unable to transmit a control signal to a receiver. It is installed in a cavity  51  formed in the body  2  on the opposite side of the axis of the handle  4  to the first cavity  5 . This second pushrod  50  also has a head end  52  coming to rest under the skirt  10  of the handle  4  and a foot end  53 . This foot end  53  butts against the bottom of the second cavity  51  and has a collar  53  that butts against the top part  56  of the cavity  51 . This cavity  51  runs parallel to the axis X-X and between the levels defined by the bottom  8  of the first cavity  5  and the rest position defined by the second shoulder  35  of the first cavity  5 . 
   This second pushrod  50  is urged by a third compression spring  60  inserted between the collar  55  and the bottom of this cavity so as to elastically urge this second pushrod  50  and cause the operator to have to exert the same force on the handle  4  when depressing the first pushrod  3  or the second pushrod  50 . 
   Thus, only the first pushrod  3  is equipped with means for controlling a receiver while the second pushrod  50  is simply there for the sake of the symmetry of the forces that have to be exerted on the handle  4 . The number of component parts is thus reduced so as to minimize the cost and the risks of technical failure. 
   Furthermore, a positive mechanical connection may also be created between the head end  12  of the pushrod  3  to guard against any possible failure of one of the compression springs or the event that the pushrod  3  remains jammed during its upward movement. 
   According to a second embodiment of the invention depicted in  FIGS. 7 to 9 , the remote control  1  for heavy construction machines comprises, as in the first embodiment and as known per se, a body  2 , at least one first pushrod  62  which is mounted to slide in the body  2  and a handle  4  which is mounted to pivot with respect to this body to control the back and forth movements of the first pushrod  62  inside the body  2 . 
   The first pushrod  62  is mounted to slide inside a first cavity  63  which runs between an open end  65  opening onto at least a top face  7  of the body  2  and a bottom  66  at the opposite end to this open end  65 . 
   As a preference, the cavity  63  comprises a shoulder  64  situated below the open end  65  and running substantially transversely with respect to the movement of the first pushrod  62 , that is to say substantially at right angles to the axis X-X. 
   In this embodiment, the pushrod  62  comprises:
         a head end  67  produced in the form of a cap comprising a cylindrical housing closed at its end  68  intended to be in contact with the skirt  10  of the handle  4 , forming a closed end,   a foot end  69  produced in the form of a cylindrical rod of a diameter smaller than the housing in the head end  67  fixed to the closed end of the latter coaxially via one of its ends,   an intermediate portion  70 , of cylindrical overall shape, comprising a cylindrical housing  72  to accommodate the opposite end of the cap that constitutes the head end  67  to the end that is intended to be in contact with the handle  4 .       

   The closed end of the housing  72  comprises a central opening  73  of axis XX and with a diameter more or less equal to the rod of the foot end  69  allowing the latter to pass. 
   This arrangement guarantees that the foot end  69  and the head end  67  move as one, and can move translationally along the axis XX with respect to the intermediate portion  70 . 
   The head end  67  of the first pushrod  62  comes into abutment under the skirt  10  of the handle  4  and is commanded between its rest position as depicted in  FIG. 7  and its depressed position as depicted in  FIG. 8  in the way well known in the state of the art. 
   The foot end  69  of the pushrod  62  is housed in the bottom  66  of the cavity  63  to control at least one first receiver external to the remote control. 
   According to an essential feature of the present invention, the head end  67  of the first pushrod  62  can also move into a protruding position as depicted in  FIG. 9 , this protruding position being on the opposite side of the rest position to the depressed position. 
   To this end, the remote control according to the present invention has first elastic return means  74  consisting of a spring  74  housed axially between the bottom of the housing  72  and the closed end  68  of the cap that forms the head  67 . 
   The first elastic return means  74  urge the head end  67  of the first pushrod  62  into its protruding position so that the head end  67  of the pushrod  62  has its own inherent upward movement. During this upward movement, the handle  4  is pivoted to disengage the head end  67  of the pushrod  62  so that this head end  67  has an upward movement to follow the skirt  10  under the action of the first elastic return means  74  into its protruding position. 
   The intermediate portion  70  has a top face  75  which delimits a top stop and a bottom face  76  which delimits a bottom stop. The top face  75  faces toward the shoulder  64  while the bottom face  76  faces toward the bottom  66  of the cavity  63 . 
   Thus, during the back and forth movements of the pushrod  62  inside this cavity  63 , the top stop  75  is intended to come to rest against the shoulder  64  as depicted in  FIGS. 7 and 9  when the pushrod is not in the depressed position, while the bottom stop  76  is intended to come to rest against the bottom  66  of this cavity when the pushrod is in the depressed position as depicted in  FIG. 8 . 
   The shoulder  64  thus somewhat defines the rest position of the pushrod  62 . 
   Furthermore, according to another essential feature of the invention, the remote control  1  has second elastic return means  77  which are housed in the cavity  63  to return this first pushrod  62  from its depressed position as depicted in  FIG. 8  to its rest position as depicted in  FIG. 7 . 
   The second return means  77  preferably comprise a collar  78  borne by the intermediate portion  70  near the top stop  75 , this collar facing toward the bottom  66  of the cavity  63 . The second elastic return means  77  also comprise a second compression spring  79  which is inserted between the collar  78  and the bottom  66  of the cavity  63 . This compression spring  79  has a diameter slightly larger than that of the intermediate portion  70  so that it can be pushed onto this portion until it reaches the collar  78 . 
   As in the first embodiment, in order to control said first external receiver, the remote control  1  comprises detection means  17  for detecting any position occupied by this first pushrod  62  between its protruding and depressed positions. 
   The pushrod  62  is in equilibrium in its rest position between the action exerted by the skirt  10  on the head end  67  which tends to depress the pushrod  62  and the action of the first compression spring and of the second compression spring  74  and  79 . In this rest position, the top stop  75  rests against the shoulder  64  while the head end  67  abuts axially against the closed end of the housing  72  of the intermediate portion  70  under the action of the handle  4 . The first spring  74  is compressed. 
   When the pushrod  62  is in its depressed position as depicted in  FIG. 8 , the skirt  10  of the handle  4  urges the head end  67  of the pushrod  62  downward so that the intermediate portion  70  compresses the second compression spring  79  until this intermediate portion  70  is in abutment downward against the bottom  66  of the cavity  63 . 
   Conversely, when the head end of the pushrod  62  is in its protruding position as depicted in  FIG. 9 , the head end  67  of this pushrod has been disengaged by the skirt  10  of the handle  4  so that the intermediate portion  70  has come into abutment upward against the shoulder  64  under the action of the second compression spring  79 . Likewise, the first compression spring  79  relaxes. The head end  67  is no longer axially in abutment against the closed end of the housing  72  of the intermediate portion  70  when the head end  67  of the pushrod moves from its rest position into its protruding position. 
   The head end  67  of the pushrod  62  can occupy any position between its depressed position and its protruding position depending on the inclination given to the handle  4 . 
   The foot end  69  of the pushrod  62  extends beyond the bottom  66  of the cavity  63  so as to pass through this bottom in the back and forth movement between its protruding and depressed positions. 
   As a preference, as in the first embodiment, the detection means  17  are of the type free of mechanical contact and comprise for example a magnet  40  which moves as one with the foot end of the pushrod  62  by being mounted inside the latter, and a Hall-effect sensor  41  mounted in the body  2  of the remote control  1  facing the movement of the magnet  40  between the depressed and protruding positions of the first pushrod  62 . More specifically, the Hall-effect sensor  41  is mounted in the body  2 , beyond the bottom  66  of the cavity  63 . Thus, this sensor  41  may be potted in a substance such as resin in order to seal it. 
   To balance the handle  4  and in a similar way to the first embodiment, a second pushrod  80  is installed in the body  2  of the remote control  1  to balance the handle  4 . This second pushrod  80  is a passive pushrod in as much as it is unable to transmit a control signal to a receiver. It is installed in a cavity  82  formed in the body  2  on the opposite side of the axis of the handle  4  to the first cavity  63 . 
   This cavity  82  is symmetric with the first cavity  63  about the axis of the handle. It comprises a shoulder  86  symmetric with the shoulder  64  of the first cavity. The bottom of this cavity is not pierced like the first cavity  63 . 
   This second pushrod  80  also has a head end  83  coming to rest under the skirt  10  of the handle  4  and a portion  84  secured to the head end  83 . In this second embodiment, the portion  84  of the second pushrod  80  is identical to the intermediate portion  70  of the first pushrod, and the head end  83  of the second pushrod is identical to that head end  67  of the first pushrod  62 , these two parts however being joined together, unlike the first pushrod  62 . 
   This portion  84  butts against the bottom of the second cavity  82  and has a collar  85  that butts against the shoulder  86  of the cavity  82 . This cavity  82  runs parallel to the axis X-X and between the levels defined by the bottom  66  of the first cavity  63  and the rest position defined by the shoulder  64  of the first cavity  63 . 
   Furthermore, this second pushrod  80  is urged by a third compression spring  86 , identical to the first compression spring  74 , which is inserted between the collar  85  and the bottom of this cavity so as to urge this second pushrod  80  elastically and cause the operator to have to exert the same force on the handle  4  to depress the first pushrod  62  or the second pushrod  80 . 
   The number of component parts is reduced by comparison with the first embodiment so as to minimize the cost and the risk of technical failure. 
   The assembly of a remote control according to this second embodiment is simplified by the use of components that are the same for the first and for the second pushrods. 
   Furthermore, the travel of the first compression spring is reduced by comparison with the first embodiment. 
   According to a third embodiment depicted in  FIGS. 10 to 12 , all the component parts are identical to the second embodiment except for the second pushrod  87  which in the same way comprises a head end  88  and a portion  89 . However, the head end and the portion are not secured to one another, a compression spring  90  being housed between the head end  88  and the portion  89 , in a similar-way to the first pushrod. In this case, the head end  88  of the second pushrod  87  follows the skirt  10  of the handle  4 . 
   This arrangement improves the symmetry of the assembly, avoiding assembly errors, and in addition guarantees that a couple in the handle will be symmetric between the depressed and protruding positions. 
   Of course, the invention is not restricted to the examples described hereinabove and various modifications can be made thereto without departing from its scope.