Note: Descriptions are shown in the official language in which they were submitted.
WO95/3061~ 21 8q~6 r~ L ~
TURNING DEVICE AND CAM GUIDE MECHANISM INCLUDED TE~EREIN
Fleld of the Invention
This invention relates to a device for turning an
ob~ect, and more sp~ f~ y cnn- -~rnC a turning device
as set forth in the preamble to ~L~ claim l. The
5 invention further relates to a cam guide ---hF~n~
intended for use in the turning device.
8~ Luulld o the Invention
Various ~;UIIV~yUL~i, p~k~ln!T r~~h~n~c and the like
10 are used for conveying and h;ln~ll 1n~ ob~ects, and fre-
quently require that the objects can be turned through a
predet~ n~d angle. The reason for this may be that the
ob~ ect is to be oriented in another direction and subse-
quently be further c;u--v~y~d by the same ~;UIIV~yUl, or that
15 the object is to be LLal~:~rt:LL~d to another ~UIIVC:yUL and
thus has to be turned through a predet~rrf n~l angle, for
instance an angle of 90.
In both cases, the object at issue is frequently
conveyed by some sort of ~;UIlvl:yuL, for instance a belt
20 Cullvl::yu~, up to a turning site or ~unction, where the
object is LaLlly stopped and first is lifted a cer-
tain distance in the vertical direction by one and the
same turning device so as to be released f rom the con-
veyor and be lU~ OL l.~dd by the turning device. The object
25 is then turned through the predet~ npd angle and is
flnally lowered so as to rest on the ~ IIVe:yUL in the
turned positlon. Thus, the turning operation often
involves a lifting operation.
US-3, 100,039 teaches a conventional method of
30 achieving the, I n~l lifting and turning operation
~l~c~ h~ above. The US d~ describes a turning
device intended for use in association with a ~;ullv~yul.
This turning device comprises a turntable which, with the
aid of a first pneumatic piston and cylinder unit, is
35 movable in the vertical direction along an axis between a
Wo 95/30612 ~ 2 1 8 9 5 5 6 ~ . J~ --
lower posltion on a level with an ad~ oining ~;u-lvey~l belt
and an upper positlon above the e~-lvey~L belt. Further-
more, the turntable is, with the aid of a second pneuma-
tic piston and cylinder unit, reciprocatingly turnable
5 about the axis within a restricted angular range.
l~owever, this prior-art ~ xLLueLlon suffers from a
numher of IL~r/ba~hs~ Thus, the linear lifting and lower-
ing ,~ t of the turntable, as well as the turning
~. L thereof, is brought about with the aid of
10 various driving means. This constitutes a ~ ted
solution, since the relative ~ Lx of the driving
means thus have to be :~y~;llL~Ilised. In addition, the
turning ~ L i of the turntable are reciprocating,
the forward v. L actively causing an object to turn,
15 whereas the ba-_}.wc-Ld v~ L merely rêturns the turn-
table to a suitable position in view of a subsesluent
forward v. L for turning the object. As a result,
only every other turning v L of the turntable is an
elctive . L, i.e. causes the Xu~oL L~d object to
20 turn. Also, this conventlonal construction is disadvan-
tageous in that the ~ , , Lx involved in the
turning operation are subJected to a cnnc1rl~rable load
when heavy objects are to be lifted and turned.
There is thus a demand for a better solution than
25 the one offered by the prior-art ,;ol~xLLu~,Llon described
above .
One ob~ect of the invention is to provide a device
which is adapted to turn an ob~ect while the latter
undergoes a linear reciprocating ~ L, ~Rr~n1~lly in
30 the vertical direction, and which obviates the rlr~wh~r-kR
mentioned above.
Another object of the invention is to provide a
turning device which is sub~ected to less torsional
stress than prior-art devices.
wo 95130612 2 ~ 8 ~ 5 -5 6 r~l
Sum.mary of the Invention
According to the invention, these and other objects
are attained by a turning device having the distinctive
features recited in ;~ '1 claim l, ~ GLeLLGd embodi-
5 ments of the turning device being defined in cl~r~n~ntclaims 2-lO.
The invention further provides a cam guide ~h~n~ cm
having the distinctive features recited in i n~ r.onA~nt
claim ll, preferred '-'1 L~i of the cam guide mecha-
nism belng defined in ~r~n(1~nt claims 12-14.
The present invention has several adva~lLauGs over
the prior art. The fact that a single driving means,
which may be of simple and conventional design, achieves
not only the lifting and lowering ~ L but also the
turning v L results in a uu.1~LLu.;Llon which, gene-
rally cp~Flk; ng, iS less expensive than prior-art turning
devices. In addition, the use of a single driving means
of simple design increases the service life of the turn-
ing device, since there are but a few ^h~nir~l compo-
nents running the risk of being exposed to wear. Further-
more, there is no need of :,y11u11Lvl~ising several sG~JaLaLG
driving means during the turning cycle.
The inventive ~ul.~LLu~Llon, in which the turning
,~. L is achieved by ~u11vGL l,lng a ~ , ~ of a
linear force to a torsional force, further entails that
the - lr~l L~ involved in the turning opera-
tion are not exposed to torsional stress of any signif i-
cance. This means that the device is able to take up a
greater load and that the ~ , L parts are not much
worn.
The invention further enables the prior-art, inac-
tive, backward turning .VG L to be ~1~ cr~nc~rl with,
since the turning ,-,. L according to the invention
can be achieved contin1~n1Cly in the same direction.
It should further be G ~ C~ that the linear
,~ L of the turning device and the cam guide mecha-
nism according to the invention may be vertical, as will
WO 95/30612 2 1 8 q 5 5 6 F~1 ~ 5'1 '
be described below in connection with the ~ fall~d emho-
diment of the invention, as well as non-vertical, for
instance horizontal. Thus, the ~rpDn~lD~l claims are meant
to ~ all conceivable directions of the axis of
~. 1 of the device, and all references in the fore-
going as well as in the following to a lifting and lower-
ing Y L, as well as to a ~ ~ in the vertical
direction, are to be i.l~ d accordingly.
Brief Description of the Drawings
A L,l~=fellad: -'1 L of the inventive turning
device in the form ~f a turntahle, as well as an inven-
tive cam guide ^h~n1~ nrl u~9PA therein, will now be
rlD~I-r~ hD-l in more detail with lt:Lt:Lc:.-u~: to the Rl _ y~
ing drawings, in which
Fig. l is a side view of the turntable, which is
~11 qpo1 Dfl in a roller .u11vt:yol and shown when occupying
a lower initial position,
Fig. 2 is a top view of the turntable and the con-
veyor in Fig. l,
Fig. 3 is a side view of a ~rame forming part of the
turntable,
Fig . 4 is a top plan view of a ~ acket for the frame
in Fig. 3 when in flat state,
Fig. 5 is a section taken along the line A-A in
Fig. 3,
Fig. 6 is a side view of a lifting piston forming
part of the turntable,
Fig. 7 i9 a section taken along the line B-B in
Fig. 6, and
Fig. 8 is a side view of a cam follower adapted to
be mounted in the lifting piston shown in Fig. 6.
Description of a Preferred ~m~o~
In Figs l and 2, the turntable is ~i~ qpo~Dd in a
horizontal roller ~:UIIV~:yUl with rollers lO0 mounted in a
stand llO, the turntable being here adapted to turn some
1-- wo 95130612 2 ~ 8 9 5 5 6 r~ 5 ~
gort of object, for instance a carton (not shown), about
a vertical axis 1 through an angle of 90 in the direc-
tion indicated by the arrow a.
As appears rom Flg. 1, the turntable comprises a
driving means in the form of a vertical piston and cylin-
der unit 2 ~nnlll~11n~ a cylinder 3 and a piston rod 4
which is reciprocatingly movable along the axis 1, as
well as freely turnable about the latter. The turntable
further comprises a ~:iUyyUL Ling means 5, which is intended
to support the ob~ect and 1 n~ q an elongate lifting
piston 6, which is centred round and extends vertically
along the axis 1 and which, at its lower end, is rigidly
connected to the piston rod 4 by means of a screw joint
8. The ~UyyUL Ling means 5 is thus vertically adjustable
along the axis 1, as well as tllrnAhle about the latter.
It appears from Figs 6-8 that the lifting piston 6 at its
lower end has four L~utz~ses 7, which are directed radial-
ly inwards and each are adapted to ~- ' Lt: a cam fol-
lower 11 in the form of a roller bearing which, with its
inner rlng, is r~L~:I-ed by screws ln the Lc:~ye.;Llve
recesses 7.
The :~UyyUL Llng means 5 further comprlses two ortho-
gonal ~uyyuLLlng plates 12, 13 whlch, by the lllt ~1~ry
of a spacer 10, are connected to the upper end of the
llftlng piston 6 and which Lu~t:LlleL form the shape of a
cross perp~n~1c~ r to the axls 1.
As appears from Flg. 1, the supportlng plates 12, 13
are, ln the initial position of the turntable, located on
a level beneath the upper periphery of the rollers 100.
It i8 further evident from Figs 1 and 3-5 that the
turntable comprises a frame 16, whlch ls statlonary ln
relatlon to the stand 110 of the uullve:yvI and which
~nf ~ q an elongate, cyllndrlcal ~acket 18, whlch ls
centred round and extends vertlcally along the axls 1 so
as to surround essentlally the entire lifting piston 6.
The lnslde r~ e~ of the jacket 18 ~;uLL~2:iyul~ds to the
~i; L~L of the llftlng plston 6. The jacket 18 ls clamp-
. . . _ _ . _ _ _ _ _ _ _ _ . _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
WO95/30612 ~ 1 89556 F~1__ 5 '
ed in, and XU~JIJUl L~d by, a ~iU~l~)Ul Llng element 20 of the
frame 16, this elenent being aLlally~d above the piston
and cylinder unit 2 and having an opening for receiving
the latter. The ~acket 18 is made up of two Yub,,La--Llally
5 identical parts, namely an upper part 22 and a lower part
24, which are rigidly illLt:l~;ullllected with the aid of four
vertical connecting rods 26.
The jacket parts 22, 24 are shown in flat state in
Fig. 4, from which it appears that the ~acket-part ends
10 facing one another are provided with recesses in such a
manner that there is formed, between the two lacket parts
22, 24, an undulated, LhLu~ Jv1n~ guiding groove 28 run-
ning ~nrll ~IRl y in the ci ~:ul~Ler~:llLlal direction and being
adapted to ~ ' L~: the cam fol 1 x 11. The guiding
15 groove 28 has a width corrp~pnnrl~n~ to, but being slight-
ly larger than, the rli Ler of the cam followers 11.
The guiding groove 28 comprises vertical lower por-
tions 30, forming the troughs of the guiding groove, and
vertical upper portions 32, forming the crests of the
20 guiding groove. A vertical~ axis 34 extends through each
vertical portion 30, 32 and is horizontally centred
therein .
Ful i ~, the guiding groove 28 comprises upward-
ly ;nr.l ~n~-l portions 36, each having an upper cam surface
25 38, as well as ~ lly ;nr.l ;n~ portions 40, each hav-
ing a lower cam surface 42. Each upper cam surface 38
extends from a du dly-directed narrow end 44, which
consists of the transition between one of the d. dly
1 nrl; n~A portions 40 and one of the upwardly ~ nrl i nP~l
30 portions 36, to the point where the guiding groove 28
pâsses from the upwardly; nrl; nP~l portion 36 to an upper
vertical portion 32. Each lower cam surface 42 extends
from an upwardly-directed narrow end 46, which consists
of the transition between one of the upwardly I nrl ~ nF~
35 portions 36 and one of the ,' - - dly lnrl ;n~ portions
40, to the point where the guiding groove 28 passes from
WO 95/30612 2 1 8 9 5 5 6 P~
the ~n~ ~. dly 1 n~ l ~ n~cl portion 40 to a lower vertical
portion 30.
Each ~ - dly-directed narrow end 44 and each
upwardly-directed narrow end 46 are offset in the late-
5 ral direction ( to the lef t in Fig . 4 ) in relation torespective axes 34, i . e . in relation to the centre of
respectively the lower and the upper vertical portions
30, 32 of the guiding groove 28.
The turntable operates as follows. In a lower ini-
10 tial position, the piston rod 4 of the piston and cylin-
der unit 2 occ~ri ~c a retracted position, ln which the
ZiUlll.)UL Ling plates 12, 13 are located on a lower level
than the upper periphery of the rollers 100, and in which
each cam follower 11 o--r--rl ~c a startlng position Pl
15 ( shown in Fig . 4 ) and rests on the bottom of one of the
lower vertical portions 30 of the groove 28, the cam fol-
lower 11 thus taking up the dead weight of the supporting
means 5.
Initially, the ob~ect to be turned ls ~_u-lv~5yGd to a
20 position above the supporting plates 12, 13 by means of
the C;UIIVG-~YU1. The plston and cylinder unit 2 is then
~_LuaLG-d, causing the piston rod 4 to perform a linear
lifting ~ L along the axis 1. As a result of the
upward linear ~ L of the piston rod 4, the lifting
25 piston 6 is likewise moved upwards, each cam follower 11
received in the guiding groove 28 being, owing to this
linear ~ L, caused to follow the lower vertical por-
tion 30 of the groove 28 up to a lower inL ~ te posi-
tion P2. Having reached this lower illl '1~te position
30 P2, the cam follower 11 ellcùu--LGLr the upper cam surface
38 and is thus forcibly applied against the latter as the
lifting .VG L continues. The linear force y'Gn'GLClLed by
the piston and cylinder unit 2 is, as a result, partly
C;UIIVGL LGd to a torsional force, such that the piston rod
35 4 and the supporting means 5 will, in addition to the
lifting ~ L, be subjected to a turning ~ L. The
cam follower 11 travels in contact wlth the upper cam
WO9~/30612 21 89 55 6 8 r~
surface 38 along the entire length thereof, up to an
upper turning position P3, where the cam follower 11 is
located in the upper vertical portion 32 of the guiding
groove 28. In the turning position P3, the piston rod 4
5 and the supporting means 5 have, as seen in Fig. 2, been
turned ant~ rl Qrkwi qe through a part angle of 45 in rela-
tlon to the starting position.
When the cam follower has reached the turning posi-
tion P3, the supporting means 5 is thus completely up-
10 lifted. As a result of a subsequent linear lowering move-
ment of the piston rod 4, the cam follower 11 is moved
vertically flc~:- ds from the turning position P3 to an
upper i~ Ate position P4, where the cam follower 11
instead cllUUUll~.cL` the lower cam surface 42. As the
15 lowering v 1, continues, the cam follower 11 travels
in contact with the lower cam surf ace 42 along the entire
length thereof to a lower ill~ '~Ate position P5, the
supporting means 5 and the piston rod 4 being thus com-
pelled to turn anticlockwise, as seen in Fig. 2, through
20 a second part angle of 45 . Finally, the supporting means
5 is lowered in the vertical direction without turning,
such that the cam follower 11 reaches an end position P6,
which corresponds to the starting position P1, the only
difference being that the end position P6 is located in
25 a sl~rr~cq~ve trough of the guiding groove 28, as ~ cd
with the trough where the starting position P1 is locat-
ed. The supporting plates 12, 13 will thus again be
located on a level beneath the upper periphery of the
roller8 100, thus r~lPAqin~ the object from the support-
30 ing plates. The piston and cylinder unit 2 has thus com-
pleted a cycle consisting of a lifting and a lowering
vc ~, while the supporting means 5 simul~An~ qly has
been turned through 90 . It will be appreciated that the
end position P6 constitutes the starting position P1 of
35 the subsequent cycle of v, 1,.
ûwing to the special design of the groove with lower
and upper narrow ends 4~, 46 offset in~ the lateral direc-
~ WO 95/30612 2 1 8 9 5 5 ~
tion in relation to the axis 34, the cam follower 11 will
be brought into direct application against the respective
upper and lower cam surfaces 38, 42.
Thus, the object to be turned is first located on
the `UJ)IJUl Llng rollers 100 above the turntable at a dis-
tance therefrom. When the driving means 2 is actuated,
the ob~ect is first lifted a small distance, such that
the `'U~y~L Llng plates 12, 13 come to occupy a level above
the upper periphery of the rollers 100 in order not to be
i.-LcLrelc~ with during the :iub~e~uc~.L turning ~ L.
As the lifting ~ L continues, the ob~ect is gradual-
ly turned through 45 in a Ç~LcdclP~ nP~l direction. ~hen,
the driving means 2 is actuated ln the opposite direc-
tion, such that the object is lowered and thus simulta-
neously is turned through another 45 in the same direc-
tion. Finally, the turntable is lowered beneath the sup-
porting rollers 100, and the ob~ect thus turned through
90 again rests on the supporting rollers to be further
~ --vcycd thereby.
It will be appreciated that all the cam followers 11
simultaneously perform a ~ LL-~L~ ng ~c L in thelr
c~e~Llve parts of the endless undulated guiding groove
28. It is also to be u-,deL~Luod that the ~'UL,IJ~JL Llng means
will be turned through another 90 in the same direction
during the subsc~uc--t cycle of ~. L of the piston and
cylinder unit 2.
Conceivable Modifications of the Invention
It goes without saying that the invention is by no
means restricted to the preferred _]1 L described
above, but can be '1f1P~l in many ways within the scope
of the appended claims. For instance, the vertical por-
tions 30 and/or the vertical portions 32 may be dispensed
with. Also, the 1nr~ nPcl portions need not be straight
but may, for example, have the shape of half a parabola.
In addition, the ~ acket parts 22, 24 may be mutually
turnable about the axis 1, thus Pn;qhl lng turning in both
, _ _ _ _ _ _ _ _ _ _ _ _ _ . _ . .... .. . .
WO 95/30612 2 1 8 9 5 5 6 I ~ C: ~
directions. There may be provided one cam follower 11
only. r5J~ v~:r, the guiding groove 28 and the cam fol-
lowers 11 may change places, i.e. the guiding groove 28
may be provided in the lifting piston 6, while the cam
5 followers 11 are stationarily ::iU~ )Ul L~d by the frame 16 .
Finally, it should once more be ~mrh~ ed that the use
of the turning device need not be focused on the vertical
direction, for which reason the expressions "up" and
"down" as well as "upper" and "lower" Lh-~Juyll~uL are to
10 be illLc~ dLed in the broad sense, as referring to oppo-
site directions in relation to the ori entation of the
main axis.