JPS5844537B2 - Strap cutting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a strap cutting device, and more particularly to a strap cutting device in which the support structure of the cutting head is significantly simplified and lightened.

In the past, various strap cutting devices have been proposed and put into practical use, and most of the recent ones utilize rotating blades, which are useful for tying objects with relatively low rigidity, such as aluminum cold-rolled coils. Even when cutting the bound hypertension tape, automatic cutting is possible without damaging the bound object.

A strap cutting device proposed by the present inventor as one of the co-inventors (Japanese Patent Application No. 55-129630
No. 7-55840) is an automatic cutting device that cuts a loose binding strap fixed by a movable saw blade-like strap stopper like a pair of scissors by engaging a wedge-shaped lower blade and an upper blade.

This device has the remarkable effect of reliably cutting loose binding straps.

However, regardless of whether it is a rotary blade type or made of steel, it is necessary to apply a considerable force in the width direction of the strap during the cutting stage or pre-cutting stage, and therefore the cutting head is required to support the reaction force. The support mechanism had to be a sturdy structure.

Therefore, the inventors of the present invention proposed that if the binding strap is cut by the relative movement of two sliding members with blades through the screw shaft, almost no force in the strap width direction will be applied to the cutting head support mechanism. We have discovered what can be done and arrived at the present invention.

The object of the present invention is to provide a strap cutting device whose cutting head itself is extremely compact and whose support mechanism is particularly simple and lightweight.

Another object of the present invention is to provide a strap cutting device that can reliably cut straps even if the surface of the object to be bound is uneven or loose.

According to the present invention, there is provided a screw shaft which is disposed inside the cutting head, is arranged parallel to the surface of the object to be bound, and whose both ends are pivotally connected, and which is screwed onto the screw shaft and is slidable in the direction of the screw shaft. a first sliding member having one end pivotally attached to the lower part thereof and a wedge-shaped blade with a protrusion that presses the surface of the object to be bound and holds the edge of the strap at the other end; A second shaft is driven by the prime mover through the drive shaft and has a geared nut pivotally mounted therein which is threadedly engaged with the screw shaft, and has one end pivotally connected to the lower part thereof and the other end having a wedge-shaped blade for pressing the surface of the object to be bound. and a sliding member, and as the first sliding member and the second sliding member approach each other due to the driving force of the prime mover, a pair of wedge-shaped blades provided at the lower part of each of the first sliding member and the second sliding member are attached to the surface of the object to be bound. A strap cutting device is provided which is characterized by scooping up and shearing straps.

The present invention will be explained in detail below using Examples.

FIG. 1 is an overall perspective view showing an embodiment of the present invention.

As shown in FIG. 1, the coil 2 whose outer periphery is bound with the strap 1 is conveyed to the position of the cutting device 4 by the conveyors 3, 3.

The cutting device 4 includes a machine frame 5, a hydraulic cylinder 6 vertically attached to the machine frame, and bearings 7, 7 fixed to the machine frame.
A cutting head 10 is attached to the tip of the guide rod 8 and the piston rod 9 of the fluid pressure cylinder 6 and is movable up and down vertically in accordance with the coil surface. configured.

FIG. 2 is a front view showing a state in which the cutting head 10 is in contact with the surface of the coil 2. At both ends of the bottom of the frame 11, there are shock absorbers 1 made of wood or synthetic resin such as hard nylon.
2 is captured.

FIG. 3 is a bottom view of FIG. 2, in which the buffer bodies are tightened with sinking bolts at both ends, and the wedge-shaped upper blade 19 that is bent is attached to the pin 2.
The first sliding member 25 is pivotally connected at 8, and the wedge-shaped lower blade 2
A state in which the second sliding member 26, to which 0 is pivotally attached by a pin 29, is screwed onto the screw shaft 31 is shown.

FIG. 4 is a sectional view taken along line IV-fV' in FIG.

Buffer bodies 12.12 are attached to both legs of the bottom of the frame 11, buffering the space between the objects to be bound and the cutting head, and regulating the appropriate stroke between the lower ends of the moving members of both tanks and the surface of the objects to be bound. .

The screw shaft 31 is rotatably supported by buttons at both ends of the frame 11 by radial bearings 45 and thrust bearings 46, respectively.

One pair of each of these bearings is sufficient if Taber roller bearings or the like are used.

The first sliding member has a horizontal hole in its upper half, and a fixing nut is fitted and fixed in the horizontal hole.

That is, the first sliding member is screwed together with the screw shaft 31 via the fixing nut 17.

Further, the wedge-shaped upper blade 19 is buttoned at the lower end of the first sliding member, and is pivotally mounted by a pin 28 with its tip facing the second sliding member.

Further, the upper blade 19 is always pressed downward by the spring 30 to button, so that the tip of the upper blade 19 is always pressed downward so as to be in contact with the coil surface with the pin 28 as the center of rotation.

Therefore, even if the surface of the object to be bound is slightly uneven, the cutting edge can follow the surface, and the strap can be gripped reliably.

Next, a horizontal hole with a larger diameter than the first sliding member is drilled in the center of the second sliding member, and a gear nut 16 is rotatably supported inside the hole through a row of bearings. The gear nut 16 is screwed onto the screw shaft 31.

At the top of the second sliding member is a drive gear 14 that engages with the gear of the geared nut 16; it is supported by a pair of bearings 24 and 24 on the upper parallel shaft, and this drive gear 14 is fixed on the same axis. It is configured to be driven by an air motor 13 with a planetary deceleration bag f.

In this embodiment, the prime mover is an air motor, but it may be an electric motor, a hydraulic motor, or the like.

A shaft of a tacho generator 15 is fitted into the right end of the button drive gear 14.

Further, a wedge-shaped lower blade 20 is slidably pivotally attached to the lower end of the second sliding member 26 by a pin 29 with its tip facing the first sliding member.

The lower blade 20 in the housing is always pressed downward by the spring 32 to button, and therefore the tip of the lower blade 20 is pressed downward so as to always contact the coil surface with the pinot 29 as the center of rotation.

FIG. 5 is a cross-sectional view taken along the line v-v' in FIG. 4, and guides 27 to which liners 21 are fixed are bolted to both sides of the frame 11.

FIG. 6 is a cross-sectional view taken along VI-VI' in FIG. 4,
The second sliding member 26 is connected to the guide plate 27.27 and the liner 2.
1. It can be moved by being guided by 21 degrees.

FIG. 1 is a sectional view taken along the line ■-■' in FIG.
It is possible to move by being guided by.

The structure of the embodiment of the present invention differs from that described above.

The effects will be explained below.

Before the start of normal operation, the cutting head 10 is located at the upper part of the machine frame 5, and when the coil 2 is carried in and stopped, fluid pressure is applied to the cylinder 6 by the limit switch and the cutting head 10 is lowered.
touches the top surface of the

Furthermore, the first and second sliding members are separated into the left and right end positions inside the cutting head 10, and at the same time the cutting head 10 comes into contact with the upper surface of the coil, compressed air is supplied to the air motor 13, and the air motor is activated. When rotated, the drive gear 14 rotates and the gear nut 16 engaged with the drive gear 14 also rotates.

The next operation can be divided into two cases.

One is when the screw shaft 31 does not rotate, and the other is when the screw shaft 31 rotates.

The first case is a case where the movement resistance of the first sliding member is greater than the movement resistance of the second sliding member.

The second case is a case where the movement resistance of the second sliding member is greater than the movement resistance of the first sliding member.

In the first case, the second sliding member is easier to move than the first sliding member.

Therefore, the screw shaft 31 does not rotate, and the second sliding member 26 moves in the direction of the strap 1 due to the rotation of the toothed nut inside the second sliding member 26, so that the tip 20A of the lower blade 20 touches the edge of the strap 1. I ended up coming into contact with one person.

In the second case, the screw shaft rotates together with the geared nut because the first sliding member moves more easily than the second sliding member;
The first sliding member 25 advances in the direction of the strap 1 and the upper blade 19
The protrusion 19A comes into contact with the end edge 1B of the strap 1.

The first case and the second case occur alternately or in one direction,
Eventually, the first sliding member 25 and the second sliding member 26 approach each other from both sides of the binding strap 1.

FIG. 8 to FIG. 10 are conceptual diagrams showing the above-mentioned operation.

In other words, either the first or second case above occurs and the first
FIG. 8 shows a state where the second sliding members start moving toward each other, and FIG. 9 shows a state where the second sliding member coincidentally comes to the strap edge position first.

On the other hand, it goes without saying that the first sliding member may reach the strap edge position first from the left.

In any case, the first and second sliding members first approach each other until their respective wedge-shaped blades come into contact with the edge of the strap 1, as shown in FIG. 10, and then approach each other further to cut the strap. Enter the process.

FIG. 11 is a conceptual diagram showing the final stage of the cutting process.

This cutting process will be explained in more detail below.

FIG. 12 is an enlarged perspective view of the wedge-shaped upper blade 19 attached to the lower part of the first sliding member.

That is, the wedge-shaped upper blade 19 has a notch 19B into which the lower blade 20 is fitted, in order to facilitate engagement with the wedge-shaped lower blade 20 on the other side.

It also has a protrusion 19A for gripping the edge of the strap.

A shearing blade portion 19C is formed along the surface of the housing strap.

In addition, Fig. 13 shows the wedge-shaped lower blade 2 attached to the lower part of the second sliding member.
0 is an enlarged perspective view of FIG.

Like the upper blade 19, it has a notch 20B so that the lower blade 19 on the other side can easily engage with it, and the tip end 20A enters the underside of the strap 1, and is provided with a shearing blade part 20C.

Even if the wedge-shaped upper blade and lower blade attached to each of the first and second sliding members are replaced, the effect will not change at all, and both are within the scope of the present invention.

The wedge-shaped blade is made of JIS 5SK (carbon tool steel) or 5KS (alloy tool steel), and the shearing blade can be made of tungsten carbide or other sintered cemented carbide.

FIGS. 14 to 17 are cross-sectional views of the process in which the above-mentioned double-edged tools closely engage with each other to cut the strap 1.

As shown in Figure 14, the strap 1 has a wedge-shaped upper blade 19 on both sides.
When the protrusion 19A of the lower blade 20 and the tip 20A of the lower blade 20 come into contact with each other, and then the blades come closer together, the spring seats 19D, 20DK, 1. - Since it receives the lowering edge of the spring, the edge of the strap is firmly grasped, and the tip 20A begins to enter the underside of the strap 1 (FIG. 15).

As the two blades further approach, the shearing blade portions 19C and 20
C engages like scissors and begins to shear strap 1 (first
6) and FIG. 17, the shearing process is completed and the first and second sliding members come to rest.

At this time, the tachogenerator 15 located on the air motor drive axis also stops rotating and its output signal disappears, so a reversing relay valve (not shown) operates accordingly, the air motor 13 reverses, and the first and second The sliding member returns to its initial position.

At the same time, the cutting head also rises to the top of the machine frame and waits for the next coil or binding strap to be cut.

It goes without saying that the function of the tachogenerator described above may be replaced by some limit switches or limit valves.

By carrying out the invention described above, all of the objects of the invention can be achieved.

That is, since there is no push-cutting reaction force in the direction of the screw axis of the cutting head, a lightweight and compact automatic strap cutting device can be obtained.

Additionally, this device can reliably cut straps tied to objects with uneven surfaces or loose straps.

[Brief explanation of the drawing]

Fig. 1 is an overall perspective view showing the overall configuration of the strap cutting device of the present invention, Fig. 2 is a front view of the cutting head, Fig. 3 is a bottom view of the cutting head, and Fig. 4 is a diagram of ■-■ in Fig. 3. 5 is a sectional view along v-v' in Fig. 4, Fig. 6 is a sectional view along ■→1 in Fig. 4, and Fig. 7 is a sectional view along 8 to 11 are conceptual diagrams showing the operating state of the embodiment of the present invention; FIG. 12 is a perspective view of the upper blade; FIG. 13 is a perspective view of the lower blade; Figures 1 to 17 are cross-sectional views of the process of cutting the strap. 1...Strap, 2...Coil, 3
... Conveyor, 4 ... Cutting device, 5.
... Machine frame, 6 ... Fluid pressure cylinder, 1.
...Screw shaft, 8...Guide rod, 9...
... Piston rod, 10 ... Cutting head, 1
1...Frame 12...Buffer, 1
3... Air motor, 14... Drive gear, 15... Tacho generator, 16...
・Nut with gear, 17...Fixing nut 19...
... Wedge-shaped upper blade, 20... Wedge-shaped lower blade, 21.
...Liner, 24 ...Bearing, 25
......First sliding member, 26...Second sliding member, 27...Guide, 28.29...
・Pin, 30.32... Spring, 31...
・Screw shaft, 35, 45.46...Bearing.

Claims (1)

[Scope of Claims] 1. A screw shaft which is disposed inside the cutting head, is disposed parallel to the surface of the object to be bound, and whose both ends are pivoted, and which is screwed onto the screw shaft and slides in the direction of the screw shaft. a first sliding member which is freely movable and has one end pivotally attached to the lower part thereof and a wedge-shaped upper blade with a protrusion that presses the surface of the object to be bound and holds the edge of the strap at the other end; and the first sliding member itself has a prime mover. , a wedge-shaped lower blade which is driven by the prime mover via a power transmission mechanism and has a built-in geared nut which is screwed into the screw shaft, one end of which is pivotally connected to the lower part of the nut, and the other end of which presses the surface of the object to be bound; and a second sliding member having a blade, and as the first sliding member and the second sliding member approach each other due to the driving force of the prime mover, the first sliding member and the second sliding member are covered by a wedge-shaped blade provided at the lower part of each member. A strap cutting device that scoops up and shears the straps on the surface of a bundled object. 2 Claim 1, wherein the prime mover is an air motor
Strap cutting device as described in section.