Field of the Invention
[0001] This invention is related to an impact engraving machine which includes a pneumatic
or solenoid engraving device equipped with a striker point capable of impacting on
the engraving surface and producing on the surface a pointed deformation on each impact.
Background of the Invention
[0002] The machines of the type indicated are utilized to engrave signs and/or characters
of different type on surfaces of pieces of metal, of plastic material, etc., the whole
set of signs and characters engraved comprising a key or identification reference
or a supplier of determined information.
[0003] Thus, for example, in the automobile industry nearly all of the parts utilized carry
engraved reference numbers. It is necessary that the frame and motor of the vehicles
carry an identifying number imprinted on them.
[0004] In order to carry out this engraving, it is necessary that the striker point, besides
its axial placement originating from the engraving device, can be displaced according
to two axes perpendicular to each other, parallel to the surface to be engraved. In
order to meet these requirements machines are known which have two sides which displace
each other in perpendicular directions, activated by the corresponding motors. Machines
of this type have the drawback that they occupy a relatively large volume, due to
the existence of the two movable slides.
[0005] For the purpose of reducing the volume of the machine, machines are known in which
the engraving device is mounted on a support which can be moved in controlled manner
along an axis parallel to the surface to be engraved and also can turn in both directions
a certain angle, also in a controlled fashion, around said axis. This type of machine
is usable when the surface to be engraved does not require an excessive turn of the
striking point, in such a way that its incidence on the surface to be engraved is
practically normal in all cases.
[0006] Machines of this type are described, for example, in German patent No. 24 23 424
and in European patent No. 371,896.
[0007] In German patent No. 24 23 424, the axis over which the support of the striking device
is mounted is comprised of an endless screw which crosses a threaded bore hole of
the support. This endless screw will cause the linear displacement of the support
toward one side or the other. Also, on the lead screw there is mounted a U shaped
stirrup, the central branch of which is related to the support and with the activating
motor through the gear systems. The tipping of the stirrup causes the turning one
way or the other of the support, around the lead screw.
[0008] This configuration involves a considerable complication of the activating mechanisms,
due partly to the arrangement of the two activating motors on the chassis of the machine.
However, the turn of the support around the endless screw provokes a certain linear
displacement thereof, even though of minimal magnitude, which acts to the detriment
of precision in the engraving operation.
[0009] In the European patent No. 371,896, the axis on which the support of the engraving
device is mounted consists of a bar of circular section, along which the support can
be moved and on which it can turn a certain angle in both directions. As in the previous
case, when the two activating motors located on the chassis of the machine operate,
transmission mechanisms are required from the two motors for the linear displacement
and for the turn of the support, complicating the construction and function of the
whole.
[0010] In the two cases commented upon, the support of the engraving device is revolving
with respect to the lead screw or bar along which the linear displacement of the device
takes place.
Summary of the Invention
[0011] This invention has the purpose of a machine of the type stated, in which the support
of the engraving device can rotate and be linearly displaced in controlled fashion
on an axis, both with some systems of activation which enable simplifying the transmission
mechanism and achieving a high precision in the engraving operation. Also in a machine
in accordance with the invention, the support of the engraving device is not revolving
with respect to the part which makes up the axis along which the linear displacement
of the support will take place.
[0012] According to this invention, the axis along which the support of the pneumatic device
can be moved is comprised of a guide-bar of polygonal section, which can turn freely
on its axis. This guide-bar carries a mounted slide which can move freely along it,
and a fixed bridge which runs between the ends of the bar. The bridge in turn has
mounted on its outside a longitudinal transmission mechanism, comprised of a belt
which runs along the bridge, in parallel direction to the guide-bar, and an activating
end motor. The carrier support of the engraving device is set on the slide, directed
in a contrary direction to the one occupied by the bridge, and it is related to the
section of the belt nearest the guide-bar.
[0013] The system formed by the guide-bar and bridge is related to a tipping mechanism mounted
on the frame of the machine. This tipping mechanism is comprised of an arm which is
set perpendicularly by one of the ends to the system formed by the guide-bar and the
bridge, while on the opposite end it is capped in a toothed sector, with an axis of
turn coinciding with that of the guide-bar, which meshes with a pinion activated by
the motor. The pinion and motor are mounted on the machine's frame. The support of
the engraving device has an arm which overhangs the one occupied by the striking point
in the opposite direction, behind the bridge. This arm is crossed perpendicularly
with the section of the belt nearest the guide-bar and it has, on the front surface,
a transverse slot which can be coupled on the said section of belt, without possibility
of slipping relative to each other.
Brief Description of the Drawings
[0014] For a full understanding of the nature and objectives of the invention, reference
should be made to the following detailed description taken in conjunction with the
accompanying drawings in which:
Fig. 1 is a front elevation of an impact engraving machine in accordance with the
invention.
Fig. 2 is a left side elevation of the machine in Fig. 1.
Fig. 3 is a top view of the machine represented in Fig. 1.
Fig. 4 is a rear elevation of the system formed by the guide-bar and bridge, including
the support of the engraving device and the linear displacement mechanism of the same.
Fig. 5 is a side elevation of the guide-bar and bridge assembly, according to direction
A of Fig. 4.
Fig. 6 shows in perspective the guide-bar with the movable slide mounted on it.
Fig. 7 is a partial section according to the section line VII-VII of Fig. 1.
Detailed Description of the Invention
[0015] Referring now to the figures wherein like elements are designated by like reference
numerals, and as can be observed in Figs. 1 to 3, the machine according to the invention
includes a frame or structure 1 which is capped below on lugs 2 of angular support,
which enables locating the machine both on flat surfaces and on curved surfaces, for
their engraving.
[0016] The machine includes an engraving device 3 which is equipped with a striking point
4, which impacts on the surface to be engraved in order to produce point deformities
on it with each impact. The device 3 is mounted on a support 5 which can be moved
in controlled manner along an axis 6, parallel to the surface to be engraved, and
it can also turn in both directions a certain angle, also in controlled manner, around
the axis 6.
[0017] In the machine according to the invention, the axis 6 is embodied in a guide-bar
7, Fig. 6, of polygonal section, which can adopt for example a section approximately
rectangular, having angular longitudinal channels 8 coming from two of its opposing
faces. In this guide-bar, a slide 9 is mounted which partially covers the bar between
the channels 8. The slide 9 is the bearer of race elements which will facilitate their
sliding along the bar 7.
[0018] The guide-bar 7 also has mounted between its ends a fixed bridge 10, Figs. 1, 4 and
5. As observed in Fig. 1, the system formed by the guide-bar 7 and the bridge 10 is
mounted with the possibility of free turning between the laterals of the frame or
chassis 1 of the machine, by means of bearings 11.
[0019] As can be observed in Figs. 4 and 5, the bridge 10 has fastened on the outside two
end supports 12 and 13, which are carriers of pulleys 14 between which a belt 15 runs.
On the axis of the pulley 14 a pulley 16 of greater diameter is mounted which is related
by means of a transmission belt to the pulley 17 of smaller diameter which is solidary
with the axis 18 of an activating motor 19.
[0020] The support 5 of the engraving device 3 has an arm 20, Figs. 4 and 5, which overhangs
in the direction opposite to that occupied by the striking point 4, Fig. 1, behind
the bridge 10 and comes to cross perpendicularly the stretch of the belt 15 nearest
to the guide-bar 7. This arm has, coming from its front surface, a transverse slot
21, Fig. 4, in which this lower section of the belt is introduced as adjusted, without
possibility of their slipping from each other. Preferably the belt 15 will have an
internal surface transversely ribbed and the slot 21 will be limited, at least on
one of its surfaces, by a gearing 22 capable of being coupled between the ribbing
of the belt 15, in order to assure mutual anchorage.
[0021] With this construction, the displacement of the belt 15 is caused by means of the
motor 19, which will drag the arm 10 along the guide-bar 7, varying the direction
of turn of the motor the change of direction of displacement of the support 5 is achieved
and, thereby, the direction of displacement of the engraving device 3.
[0022] The motor 19 utilized for causing the displacement of the slide 7 and thereby the
engraving device 3, is mounted on the bridge 10 set at the ends of the guide-bar 7.
[0023] As is observed in Fig. 1, the system formed by the guide-bar 7 and the bridge 10
is related to the tipping mechanism which is comprised of an arm 23 which is fastened
perpendicularly at one of its ends to the said system, as a continuation of the bridge
10. The opposite end this arm 23 is capped in a toothed sector 24, Fig. 7, on an axis
coinciding with the axis of turn 6 of the guide-bar 7. The toothed sector 24 engages
with a pinion 25 with which a pulley 26 of greater diameter is solidary, which is
related to a smaller pulley 27, solidary with the axis of an activating motor 28 which
is mounted on the chassis 1 of the machine.
[0024] Activation of the motor 28, Fig. 7, will cause the rotation of the pinion 25 in the
desired direction and magnitude. When this pinion engages with the rack 24 it will
cause the tipping of the arm 23 and thereby the turn of the system formed by the guide
bar 7 and bridge 10. This turn will translate into an angular displacement of the
engraving device 3 and striking point 4, this angular displacement being of sufficient
breadth so that the striking point 4 reaches the limits of the surface to be engraved
without producing alterations in the characteristics of quality of the print produced
by each impact.
[0025] In the machine described above, the linear displacement of the support 5 and therefore
of the engraving device 3 is achieved by means of a transmission mechanism 15 and
an activating motor 19 which are mounted on the bridge 10 solidary with the guide-bar
7, while the motor 28 and transmission mechanism which causes the tipping of the engraving
device 3 is mounted on the chassis 1 of the machine. In this way one achieves the
simplification of the transmission mechanism and obtains a maximum exactitude and
safety both in the linear displacement movement and in its tipping movement.
[0026] The system of fastening of the support 5 to the transmission belt 15 is simple and
of great safety. The motor 28, in turn, which will produce the tipping of the engraving
device 3 is mounted on the structure of the machine and the transmission mechanism
between said motor and the guide-bar 7 is comprised of a system of gears which makes
it possible to achieve the maximum precision in the angle of tipping of the striking
point 4.
[0027] As is observed in Figs. 1 to 3, the machine can be equipped with upper handles 30
which facilitate its manipulation in the portable version.
[0028] The system permits marking on two planes located up to 90° apart, only by increasing
the arc of turn by means of the parts 24, Fig. 7.
[0029] Although a certain presently preferred embodiment of the present invention has been
specifically described herein, it will be apparent to those skilled in the art to
which the invention pertains that variations and modifications of the embodiment shown
and described herein may be made without departing from the spirit and scope of the
invention. Accordingly, it is intended that the invention be limited only to the extent
required by the appended claims and the applicable rules of law.
1. An impact engraving machine comprising a pneumatic or solenoid engraving device (3)
equipped with a striking point (4) capable of impacting on the surface to be engraved
and producing on it a point deformity on each impact, which device (3) is mounted
on a support (5) which can be moved in controlled manner along an axis (6) parallel
to the surface to be engraved, and may turn in both directions a certain angle, also
in controlled manner, around said axis, wherein said axis (6) is embodied in a guide-bar
(7) of polygonal section, freely moved along said guide-bar, and a fixed bridge (10)
which runs between the ends of the bar; said bridge bearing mounted on the outside
a longitudinal transmission mechanism comprised of a belt (15) which runs along the
bridge, and an activating end motor (19), while the support (5) bearing the engraving
device (3) is fastened to the said slide (9), directed in opposite direction to that
occupied by the bridge (10) and it is related with the section of the belt nearest
to the guide-bar (7) and because the assembly formed by the guided bar (7) and bridge
(10) is related to a tipping mechanism mounted on the frame which supports the said
assembly.
2. A machine according to Claim 1, wherein the tipping mechanism is comprised of an arm
(23) which is set perpendicularly at one of its ends to the assembly formed by the
guide-bar (7) and the bridge (10), while on the opposite one it is capped to a toothed
sector (24) with turning axis coinciding with that of the guide-bar (7) which engages
with a pinion (25) activated by a motor (28) the pinion (26) and motor (28) being
mounted on the frame (1) of the machine.
3. A machine according to Claim 1 wherein the guide-bar (7) is of an approximately rectangular
section and shows on two of its opposed faces longitudinal angular channels (8), partially
covering the slide (9) and the said bar between the channels (8) mentioned, with interposition
of bearing elements which facilitate the sliding of the slide (9).
4. A machine according to Claim 1 wherein the bridge (10) has fastened off the outside
two end supports (12, 13) which are carriers of pulleys (14) between which the belt
(15) runs the longitudinal transmission mechanism, one of these fixed pulleys carrying
a second coaxial pulley (16) of greater diameter which remains related by means of
the transmission belt with a pullys (17) of smaller diameter set on the axis of exit
of the activating motor (19), which motor is mounted on one of the external supports
(13).
5. A machine according to Claim 1 wherein the support (5) of the engraving device (3)
has an arm (20) which overhangs in the opposite direction that occupied by the striking
point (4) behind the bridge (10), which arm perpendicularly crosses with the section
of the belt (15) nearest to the guide-bar (7) and has, coming from the front surface,
a transverse slot (21) which can be coupled as adjusted on the said section of the
belt, without possibility of slipping from each other.