Information
-
Patent Grant
-
6286662
-
Patent Number
6,286,662
-
Date Filed
Thursday, January 27, 200024 years ago
-
Date Issued
Tuesday, September 11, 200123 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
-
CPC
-
US Classifications
Field of Search
US
- 198 8038
- 198 8039
- 198 4701
- 271 204
- 271 205
- 294 991
- 294 1031
-
International Classifications
-
Abstract
The invention relates to a clamp (10) for holding sheet-like objects, having a support (12) on which a clamp tongue (20) is fixed. A clamping jaw (32) is stored in a guide slot (30) in the support (12) in such a way that it can move both in and against the direction of closing (S). When the clamping jaw (32) moves from open position (34) in closing direction (S), the clamp end (42) is displaced along the path of movement (46), until it rests against the clamp tongue (20) or an adjacent object. As the clamping jaw (32) continues to move in closing direction (S), the clamp end is driven back from the path of movement (46), and a clamping force for holding the object is formed as a result of the elasticity of the clamping jaw (32).
Description
BACKGROUND OF THE INVENTION
The present invention relates to a clamp for holding flat objects as they move along a path travel.
A clamp of the generic type, designed in the manner of a pair of tongs, is disclosed in Swiss Patent No. 569 197 and in the corresponding U.S. Pat. No. 3,948,551. It has a clamping tongue which is permanently arranged on a holding part. A clamping jaw can be pivoted about an axis extending at right angles to the clamping tongue, from an open position into a clamping position, in which it forms a clamping gap with the clamping tongue. The clamping tongue and the clamping jaw can be moved relative to each other in the extent of the clamping gap, away from each other in the open position and toward each other into their clamping position. This makes it necessary for the clamp to be rotated through 90° out of and into the area defined by the object during the opening and closing operations. Simultaneous rotation of the entire clamp and the movement of the clamping jaw relative to the clamping tongue are therefore necessary which, in addition to the space requirement during gripping and releasing an object, requires complicated control. On the other hand, this known clamp has particular advantages. It is self-locking and self-retaining, it adds virtually nothing to the thickness of the flat objects and there is consequently space for it both in an interleaved formation of the objects and in the case of buffering or stacking of the objects—with a virtually constant space requirement. Furthermore, it has such a low weight that, when necessary, it can be carried and held by the object itself.
It is an object of the present invention to provide a clamp of the generic type which, while maintaining the advantages of the known clamp, is simpler to handle.
SUMMARY OF THE INVENTION
The above and other objects and advantages of the present invention are achieved by the provision of a clamp which comprises a supporting part, a clamping tongue fixed to the supporting part, a clamping jaw moveably mounted on the supporting part for movement between an open position separated from the clamping tongue and a clamping position in which a free end of the clamping jaw forms with the clamping tongue a clamping gap adapted to engage and hold a flat article therebetween, and wherein during movement from the open position toward the clamping position, the free end of the clamping jaw moves along a movement path which forms an acute angle with the clamping tongue and during continued movement after encountering an article resting on the clamping tongue the clamping jaw is resiliently deflected out of the path of movement in a direction transverse to the clamping tongue so as to produce a clamping force on the article.
Rotating the clamp according to the invention during opening and closing is no longer necessary. It is simple in construction, inexpensive to produce and extremely simple to handle. Furthermore, the clamping jaw is held in the clamping position by self-locking; locking elements are not needed. The slim construction of the clamp enables the buffering of the objects held by the clamp in the smallest possible space, while maintaining the separation of the objects; that is to say each object is gripped individually and can thus be handled individually. Furthermore, the clamp can be opened when adjacent clamps are resting on one another in a buffer.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be explained in more detail with reference to an exemplary embodiment illustrated in the drawing, in which, in purely schematic form:
FIG. 1
shows, in plan view, a clamp according to the invention in the open position;
FIG. 2
shows, in side view, the clamp shown in
FIG. 1
in the closed position;
FIG. 3
shows, in a section along the line III—III in
FIG. 1
, the clamp shown there in the open position;
FIG. 4
shows, in side view, part of an apparatus having a large number of clamps according to
FIGS. 1
to
3
arranged one behind another, a printed product being fed to each of the clamps;
FIG. 5
shows, in an identical illustration to that in
FIG. 4
, the part of the apparatus shown there with a clamp during the closing operation;
FIG. 6
shows, in an identical illustration to that in
FIG. 5
, the clamp shown there in the clamping position in order to hold the printed product;
FIG. 7
shows a further part of the apparatus shown in
FIGS. 4
to
6
with a clamp holding a printed product at the beginning of the opening operation;
FIG. 8
shows the part shown in
FIG. 7
of the apparatus with a partially opened clamp;
FIG. 9
shows, in an identical illustration to that in
FIGS. 7 and 8
, the clamp shown there in the open position;
FIG. 10
shows a further part of the apparatus shown in
FIGS. 4
to
9
, having a large number of clamps arranged one behind one another, which each hold a printed product and rest on one another for the purpose of buffering;
FIG. 11
shows, in plan view and partly sectioned along the line XI—XI of
FIG. 12
, a drive apparatus for the clamps; and
FIG. 12
shows the drive apparatus shown in
FIG. 11
in plan view.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
The clamp
10
shown in
FIGS. 1
to
3
has an essentially box-shaped supporting part
12
. As viewed in the longitudinal direction of the supporting part
12
, guide tabs
14
are integrally molded on its two ends and are intended to engage in the guide rails
16
, which have a C-shaped cross section and are open toward each other. As a result, the clamp
10
can be displaced in a sliding manner in the guide rails
16
.
On one side face
18
of the supporting part
12
there rests a flat, essentially rectangular, clamping tongue
20
, which is fixed to the supporting part
12
by means of suitable fixing means
22
, for example screws or rivets. The side face
18
lies in a plane extending at right angles to the longitudinal direction of the guide rails
16
, so that the clamping tongue
20
projects transversely to the guide rails
16
, beyond these and the supporting part
12
, in the manner of a cantilever. As shown in particular by
FIGS. 2 and 3
, the clamping tongue
20
is bent about a bending line
24
extending parallel to the longitudinal direction of the supporting part
12
, so that the free end
20
′ of the clamping tongue
20
lies approximately in a plane which is defined by that face of the supporting part
12
which has a rectangular cross section and which is located opposite the side face
18
. In addition, the clamping tongue
20
has a triangular aperture
26
in its part projecting beyond the supporting part
12
, in order to save weight. Adjacent to its free end
20
′, the clamping tongue
20
is provided with two adhesive covering strips
28
on its side which is located radially on the inside as viewed in relation to the bend.
The supporting part
12
has a guide gap
30
, through which there passes a flat, essentially rectangular, bent clamping jaw
32
. The latter can be moved from an open position
34
, shown in
FIGS. 1 and 3
, into a clamping position
36
, shown in
FIG. 2
, by being displaced in the closing direction S.
The clamping jaw
32
is bent in the manner of a segment of a circular cylinder about an axis extending parallel to the longitudinal direction of the supporting part
12
, and is guided on the supporting part
12
in such a way that the clamping tongue
20
is located on the radially inner side of the clamping jaw
32
. The guide gap
30
is shaped so as to correspond to the curvature of the clamping jaw
32
.
From its free end
32
′, facing the clamping tongue
20
, the clamping jaw
32
is provided with an approximately triangular cutout
38
, by which means two clamping limbs
40
of the clamping jaw
32
are formed, which, at their end region adjacent to the free end
32
′, are bent over, in the direction opposite to the bending of the clamping jaw
32
, to form a clamping foot
42
. In clamping position
36
, the clamping feet
42
form a clamping gap
44
with the clamping tongue
20
.
In the open position
34
, the clamping jaw
32
is located in a position in which the clamping feet
42
are located at the supporting part
12
. When the clamping jaw
32
is moved from the open position
34
in the closing direction S, the clamping feet
42
move along a circular movement path
46
which intersects the clamping tongue
20
at an acute angle α. The movement path
46
is a circular path, whose center is located on the axis of the bend in the clamping jaw
32
and whose radius corresponds to the distance from the axis to the clamping jaw
32
. In the exemplary embodiment shown, the angle α is approximately 30°. However, it can also be smaller or larger; preferably, however, it is less than 45°.
When the clamp
10
is closed in the closing direction S, the clamping feet
42
move along their movement path
46
until they come to rest on the adhesive covering strip
28
or on a flat object resting on the clamping tongue
20
. During onward movement in the direction of arrow S, the clamping feet
42
slide along the outer side, facing them, of the flat product or the adhesive covering strip
28
in the direction of the free end
20
′ of the clamping tongue
20
, as a result of which the clamping feet
42
are deflected out of the movement path
46
which they would otherwise follow further. Since the clamping jaw
32
is produced from intrinsically resilient material, for example from spring-steel sheet, and is guided in the guide gap
30
so that it cannot give way transversely to the latter, the clamping feet
42
are forced back resiliently as a result, by which means a clamping force K is produced which presses the flat object onto the clamping tongue
20
and, in particular, the adhesive covering strips
28
. Because of the acute angle a, no force component, or only a small force component, is able to act on the clamping jaw
32
counter to the closing direction S. This force component is readily absorbed by the frictional force in the guide gap
30
, so that the clamp
10
is self-retaining in the clamping position
36
.
At the end
48
opposite the clamping feet
42
, the clamping jaw
32
is provided with lateral projections
50
and bent in the manner of a tube. The projections
50
are intended to interact with an opening element, in order to displace the clamping jaw
32
from the clamping position
36
into the open position
34
, counter to the closing direction S.
The supporting part
12
comprises a supporting element
52
having a recess
54
, into which there is inserted a wedge element
56
, which engages with a retaining tab
58
behind the clamping tongue
20
and in this way is retained in the recess
54
. The supporting element
52
and the wedge element
56
bound the guide gap
30
.
FIGS. 4
to
6
show part of an apparatus
60
for processing printed products
62
, such as newspapers, magazines and the like. A transfer section
64
is shown in which, by means of clamps
10
, printed products
62
fed by a belt conveyor
66
are accepted for onward transport. In the transfer section
64
, the guide rails
16
extend in the vertical direction and the clamps
10
, which are arranged immediately one behind another and resting on one another, are moved continuously forward from bottom to top in a conveying direction F. As viewed in the conveying direction F, the clamping tongues
20
of the clamps
10
trail the clamping jaws
32
. The free end
20
′ of the clamping tongues
20
faces the belt conveyor
66
, which is intended to transport the printed products
62
in the feed direction Z in an interleaved formation, in which each printed product
62
rests on the subsequent one. On the side which is opposite the belt conveyor
66
, as referred to the guide rails
16
, there is arranged a closing apparatus
68
for the clamps
10
. The latter has an endless flexible drive member
70
, which is driven so as to circulate in the direction of arrow A at a speed v, which is greater than the speed v
f
at which the clamps
10
are moved. Arranged on the flexible drive member
70
, at intervals one behind another, are cams
72
which are each intended to interact with the end
48
of one clamping jaw
32
.
The feed speed of the belt conveyor
66
and the speed v
f
with which the clamps
10
are moved are coordinated with each other in such a way that each clamp
10
is fed a printed product
62
. As emerges from
FIG. 4
, in each case one clamping tongue
20
engages under the printed product
62
projecting beyond the end of the belt conveyor
66
and lifts this end in conveying direction F. Approximately at the same instant as the relevant clamping tongue
20
touches the printed product
62
, a cam
72
of the closing apparatus
68
strikes the end
48
of the relevant clamping jaw
32
and displaces the latter from the open position
34
in the closing direction S; this is as a result of the difference between the speed v of the cams
72
and the speed v
f
of the clamps
10
.
FIG. 5
shows that instant during the closing operation of the clamp
10
at which the clamping foot
32
comes into contact with the printed product
62
. Since, however, because of its inherent stability, the printed product
62
is not yet resting flat on the clamping tongue
20
, said product can be pushed still further in the feed direction Z into the clamping mouth, until it is brought to rest on the adhesive covering strip
28
by the clamping foot
42
. From this moment, during the onward movement of the clamping jaw
32
in the closing direction S, the clamping limb
40
, which is lengthened in the process, is stressed in the manner of a leaf spring, as a result of which a clamping force builds up, with which the printed product
62
is held by the clamp
10
for onward transport, as shown in FIG.
6
. It goes without saying that the adhesive action of the adhesive covering strips
28
on the printed product
62
is greater than the sliding friction between the clamping feet
42
and the printed product
62
. If necessary, the clamping foot
42
can be provided with a sliding covering. As is further revealed by
FIG. 6
, the clamps
10
are in each case in the closed position
36
when they reach the end of the closing apparatus
68
.
FIGS. 7
to
9
show a further part, a discharge section
74
, of the apparatus
60
already mentioned in conjunction with
FIGS. 4
to
6
. In the discharge section
74
shown, the guide rails
16
extend in the horizontal direction, and the clamps
10
are directed in the downward direction in order to transport the printed products
62
in a hanging position. The clamps
10
are moved in conveying direction F. As they enter the discharge section
74
, the clamping jaws
32
are in the clamping position
36
and each hold a printed product
62
in the clamping gap
44
formed by them and the relevant clamping tongue
20
. A wedge-shaped opening wing
76
is arranged on the two guide rails
16
. In the course of the movement in conveying direction F, the two projections
50
of the relevant clamping jaw
32
come to rest on the opening wing
76
and, in the course of the onward movement of the clamp
10
, are pulled in the opening direction, counter to the closing direction S.
FIG. 7
shows the instant at which the projections
50
on a clamp
10
touch the opening wing
76
. In the course of the onward movement, the clamping jaw
32
is pulled upward, as a result of which the clamping force K is reduced.
FIG. 8
shows the instant at which the clamping foot
42
releases the printed product
62
, so that the latter can be transferred downward to the next processing station. The clamping jaw
32
is subsequently moved completely into the open position
34
, as
FIG. 9
shows. The clamp
10
is ready to accommodate a printed product
62
again. The frictional relationships in the guide gap
30
are adequate to keep the clamping jaw
32
in the open position
34
.
FIG. 10
shows a buffer section
78
of the apparatus
60
. This section is located, for example, between the transfer section
64
shown in
FIGS. 4
to
6
and the discharge section
74
shown in
FIGS. 7
to
9
. In the buffer section
78
, the guide rails
16
likewise extend in the horizontal direction and the clamps
10
, each occupied by a printed product
62
, rest on one another. This figure shows, in particular, that the clamps
10
, as viewed in the longitudinal direction of the guide rails
16
, are designed to be extremely slim, so that they add very little in comparison with the thickness of the printed products
62
which can be held by them. As a result, a high packing density can be achieved in the buffer section.
FIGS. 11 and 12
show a drive section
80
of the apparatus
60
in elevation and plan view. In the drive section
80
, the bottom
82
of the guide rails
16
, which have a C-shaped cross section, is removed. However, the lateral limbs
84
which are connected to each other by the bottom
82
in the other sections also extend continuously through the drive section
80
, in order to guide the clamps
10
. The supporting parts
12
of the clamps
10
engage with their guide tabs
14
in the guide rails
16
, and their end faces
86
are intended to interact in the drive section
80
with driver elements
88
of a drive apparatus
90
; a drive apparatus
90
is assigned to each guide rail
16
. One of the drive apparatuses
90
, which is of symmetrical construction and arrangement, will be described below. A large number of driver elements
88
are arranged on a chain
92
, which is intrinsically closed and is guided around two sprockets
94
which have parallel axes and are spaced apart from each other in the direction of the guide rails
16
. One of these sprockets
94
is driven so as to circulate in conveying direction F by means of a drive unit (not shown). The active conveying run
96
of the chain
92
extends parallel to the relevant guide rail
16
and, with respect to the latter, is arranged in such a way that the corresponding driver elements
88
engage between the limbs
84
in the guide rail
16
and rest with frictional contact on the end faces
86
of the supporting parts
12
of the clamps
10
. A pressure and guide rail
98
arranged between the sprockets
94
ensures that the pressing force is maintained.
As can also be seen from
FIG. 12
, the clamps
10
can be moved freely in the guide rails
16
outside the drive apparatus
90
, so that they can assume a different distance from one another.
A drive section
80
can overlap, for example, with a transfer section
64
or a discharge section
74
in order to move the clamps
10
in the conveying direction F in these sections.
It is also conceivable for the clamping jaws to be designed to be flat and for the clamping shoe
42
to be moved along a rectilinear movement path as the clamp is closed and opened. The movement path forms an acute angle with the clamping tongue in this case, too.
It is of course possible for the clamps
10
and for the apparatus
60
to be designed differently.
Clamps according to the invention are suitable, for example, for use in apparatuses such as are disclosed in WO Patent Applications PCT/CH97/00200 and PCT/CH97/00201.
Printed products
62
were mentioned as an example of flexible, flat objects in conjunction with the exemplary embodiment shown. However, the clamps
10
according to the invention are also suitable for holding stiff, flat objects or flat objects of different flexibilities.
The objects can have different thicknesses. In the exemplary embodiment shown, as the thickness increases, the clamping force K also becomes greater.
The clamping tongue can be of intrinsically resilient design and, for this purpose, can be produced from spring-steel sheet, for example. Finally, it would also be conceivable to design the clamping tongue to be resilient and the clamping jaw to be flexurally rigid.
Claims
- 1. A clamp for holding flat articles comprisinga supporting part, a clamping tongue fixed to the supporting part, a clamping jaw moveably mounted on the supporting part for movement between an open position separated from the clamping tongue and a clamping position in which a free end of the clamping jaw forms with the clamping tongue a clamping gap adapted to engage and hold a flat article therebetween, and wherein during movement from the open position toward the clamping position, the free end of the clamping jaw moves along a movement path which forms an acute angle with the clamping tongue and during continued movement after encountering an article resting on the clamping tongue the clamping jaw is resiliently deflected out of the path of movement in a direction transverse to the clamping tongue so as to produce a clamping force on the article.
- 2. The clamp as defined in claim 1 wherein the clamping jaw is formed of an inherently resilient material.
- 3. The clamp as defined in claim 2 wherein the clamping tongue includes an adhesive-like surface on a side thereof facing the clamping jaw for engaging an article received thereon.
- 4. The clamp as defined in claim 2 wherein the acute angle is less than about 45 degrees.
- 5. The clamp as defined in claim 2 wherein the clamping tongue extends outwardly from the supporting part in a longitudinal direction, and wherein the movement of the clamping jaw between the open and clamping positions is along a generally longitudinal direction.
- 6. The clamp as defined in claim 5 wherein the clamping jaw is arcuately curved along its longitudinal length, and wherein the clamping tongue is positioned on the radially inner side of the clamping jaw.
- 7. The clamp as defined in claim 6 wherein the supporting part includes a guide gap which slideably receives the clamping jaw, and wherein the guide gap has a curvature which corresponds to the curvature of the clamping jaw.
- 8. The clamp as defined in claim 6 wherein the free end of the clamping jaw is bent to form a clamping foot.
- 9. The clamp as defined in claim 6 wherein the clamping tongue and the clamping jaw are each formed of a sheet material.
- 10. An article transport apparatus comprisinga plurality of clamps for holding flat articles, with each clamp comprising a supporting part, a clamping tongue fixed to the supporting part, a clamping jaw moveably mounted on the supporting part for movement between an open position separated from the clamping tongue and a clamping position in which a free end of the clamping jaw forms with the clamping tongue a clamping gap adapted to engage and hold a flat article therebetween, and wherein during movement from the open position toward the clamping position, the free end of the clamping jaw moves along a movement path which forms an acute angle with the clamping tongue and during continued movement after encountering an article resting on the clamping tongue the clamping jaw is resiliently deflected out of the path of movement in a direction transverse to the clamping tongue so as to produce a clamping force on the article, a guide rail for supporting the clamps for movement along a path of travel, a delivery conveyor for delivering an article onto the clamping tongue of each of the clamps as the clamps move past a transfer location along the path of travel, and while the clamping jaws are in the open position, a closing device positioned along the path of travel immediately downstream of the transfer location for moving the clamping jaw of each of the clamps to its clamping position and so that the articles are engaged and held between the clamping tongue and the clamping jaw of the associated clamp, and a discharge device mounted along the path of travel downstream of the closing device for moving the clamping jaw of each of the clamps to its open position so as to release the article therefrom.
Priority Claims (1)
Number |
Date |
Country |
Kind |
1613/97 |
Jul 1997 |
CH |
|
PCT Information
Filing Document |
Filing Date |
Country |
Kind |
102e Date |
371c Date |
PCT/CH98/00180 |
|
WO |
00 |
1/27/2000 |
1/27/2000 |
Publishing Document |
Publishing Date |
Country |
Kind |
WO99/01367 |
1/14/1999 |
WO |
A |
US Referenced Citations (7)
Foreign Referenced Citations (7)
Number |
Date |
Country |
569 197 |
Nov 1975 |
CH |
552 330 |
Jun 1932 |
DE |
23 03 424 |
Aug 1974 |
DE |
0 643 001 |
Mar 1995 |
EP |
1 123 381 |
Aug 1968 |
GB |
WO 9803420 |
Jan 1998 |
WO |
WO 9803421 |
Jan 1998 |
WO |