JPS59199408A - Electromagnetic clutch in band clamping device for packer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electromagnetic clutch in a band tightening device of a packaging machine.

For example, electromagnetic clutches used in packaging machines must be easy to install, have good response, and be able to rotate at high speeds. A type dry single plate clutch is used. Therefore, this electromagnetic clutch is often used in the band pulling back and tightening mechanisms of packing machines, but in packing machines, after the band has been unwound and tightened around the object to be packed, it is used to grip the band supply end side. , the roller and armature of the electromagnetic clutch slip against the tightening torque until the electromagnetic clutch is fixed and the application of the electromagnetic clutch is cut off.
The armature and drive shaft such as a pulley are connected via a leaf spring, etc., and the drive is controlled only by energizing or de-energizing the coil with a constant voltage higher than the resistance of the leaf spring. Since there is no slip on the friction surface, it is impossible to use slip as in air-gap electromagnetic clutches, and therefore it is also impossible to adjust the torque by changing the set voltage during tightening. As a result, the friction surfaces of the field core, rotor, and armature undergo severe wear, significantly shortening the life of the clutch.

゛ In order to compensate for this point, it is preferable to use a gap type powder or hysteresis clutch that can adjust the torque by voltage, but these have disadvantages such as complicated maintenance and extremely high cost. It is something that you have.

The present invention eliminates the drawbacks of conventional electromagnetic clutches in terms of cost with an extremely simple configuration.The present invention aims to eliminate the disadvantages of conventional electromagnetic clutches in terms of cost.The purpose of the present invention is to take advantage of the advantages of friction type dry single disc clutches such as good responsiveness and small size. In order to achieve the above object, it is an object of the present invention to provide an inexpensive electromagnetic clutch that can be used with a certain degree of slip. A field core containing a built-in coil is placed on a drive shaft that rotates at least the negative roller of a pair of rollers that perform tightening by pinching, a rotor that is wedged to the drive shaft and forms a magnetic pole together with the field core, and It is equipped with an armature that generates torque by being attracted to a friction plate, and a rotatable drive shaft that interlocks with the armature and is connected to a drive mechanism. The provided locking members are inserted into the respective locking members.

As shown in FIG. 1, an electromagnetic clutch 60 in a band tightening device for a packaging machine according to the present invention is attracted to a field core 63 containing a coil, a rotor 64 that forms a magnetic pole together with the field core, and a friction plate of the rotor. It consists of an armature 65 that generates torque, and a rotor 6
4 is wedge-attached to the drive shaft 11 and is rotatably provided via a bearing 69 with respect to a field core 63 that encloses the rotor 64. Also, the armature 65 is supported on the shaft 11 via a spacer 68, and has a friction side surface. The rotor 6 forms a surface.
A protrusion 66 serving as a locking member is inserted into a hole bored in the width direction of the armature 65 at an appropriate position on the other side surface in contact with the friction plate 4 so as to be integrated with the armature 65. On the other hand, a hole or recess 67 as an engaging portion is formed in the surface of the pulley 13, which is the driving wheel, in contact with the armature 65 at a position facing the projection 66, and the projection 66, which is the locking member, is formed in the hole 67. be pushed through.

Further, in FIGS. 1 to 4, reference numeral 1 denotes a band shooter, and facing this band shooter 1, a forward rotation roller 10 and a reverse rotation roller 20 are arranged at a predetermined interval. ζ is provided with a pulley 1.3 serving as a drive shaft via the electromagnetic clutch 60 mentioned above, and the pulley 13
The V-belt 14 is connected to the motor shown in the figure. Further, a gear 15 is provided on the drive shaft 11 on the side of the pulley 13 which is the drive shaft.
The gear 15 and the gear 22 provided on the drive shaft 21 of the reversing roller 20 are meshed with each other so that both rollers rotate in opposite directions. It is configured to be rotatable only in the direction of action.

In the illustrated embodiment, the gear 22 of the reversing roller has a large diameter in order to obtain high torque at low speed during tightening.

16.23 are forward and reverse touch rollers, which are supported on eccentric shafts 17 and 24, respectively, and are connected to the rollers 16 and 23.
A gear 18.25 is provided integrally with the. This gear 18, 25
is provided integrally with the forward and reverse rotation rollers 10 and 20 on the roller side thereof, and meshes with the t-coat gear 19°26.

That is, the gear 19 of the normal rotation roller 10 and the normal rotation touch roller 16
The gear 18 of the reversing roller 20 and the gear 25 of the reversing wedge roller 23 are engaged with each other, and the gear 18 of the reverse rotation roller 20 and the gear 25 of the reverse rotation wedge roller 23 are engaged with each other.
It constitutes two sets of rollers that form a pair called reverse rotation. Therefore, it goes without saying that the pair of gears 18 and 19 and 25 and 26 have the same diameter. In FIG. 2, the electromagnetic clutch 60 is attached to the drive shaft 11 of the normal rotation roller 10 by a retaining ring 6 provided at the end of the shaft 11, and a magnet 7 is embedded in the retaining ring. 8 is a rotation detection section,
The magnet 7 detects the number of rotations of the shaft 11 and is connected to a rotation detection circuit which provides an output signal when the number of rotations falls below a predetermined number.

Eccentric shafts 17 and 2 of the aforementioned normal and reverse touch rollers 16 and 23
4, the upper end of the operating rod 4040' is rotatably attached, and the lower ends of the operating rods 40, 40' are loosely inserted into the holes 42 provided in the bent pieces of the L-shaped interlocking rods 41 and 41'. interlocking rods 41, 41' through each spring 43.
Connect to. The lower end of the interlocking rod 41.41' is connected to the trochanter 45.
It is attached to the tip of the arm rod 46, 46' having a diameter of 45'.
One end of the arm rod 46, 46' is rotatably supported on a shaft 47 protruding from the base 2, and a spring 48, 48 is engaged with the other end to bias it toward the band shooter 1. In addition, in FIG. 2, LS2 and LS4 are IJit switches provided at the tips of the arm rods 46' and 46, respectively.
, and the rotation of cams 31 and 30, which will be described later, turn on and generate a predetermined signal.

Reference numerals 30 and 31 denote cams, which are attached to the arm rod 46 on a shaft extending from a cam shaft 4 that operates known gripping mechanisms 54 and 55 for the band tip and supply end, as well as welding and cutting mechanisms (not shown). , 46', so as to be brought into contact with the trochanters 45, 45' of the interlocking rods 41, 41', and hence to operate in conjunction with the operating rods 40, 40'. The camshaft 4 is rotationally driven by a speed reducer that is linked to a motor (not shown).

Note that if the bearings of the forward and reverse touch rollers 16 and 23 are of a self-aligning type, the operating rods 40 and 40
When ' is pulled down, the rollers 16 and 23 can be prevented from being pressed by the forward and reverse rollers 10 and 20 while tilting.

In the figure, 50 is a slide table, 51 is an operating piece of a limit switch LSI (not shown), 52 is a band guide, 5
3 indicates a guide roller.

Next, to describe the operation of the present invention, the pulley 13, which is constantly rotating in conjunction with a motor (not shown) via the V-belt 14, is connected to the shaft 11 and gear 15 by the electromagnetic clutch 5.
, the normal rotation roller 10 and the gear 19 integrated with the roller B are rotated counterclockwise in FIG.

Therefore, the gear 22 meshing with the gear 15 rotates the reversing roller 20 in the clockwise direction in the figure, and also rotates in the normal direction.
The forward and reverse touch rollers 16 and 23 are also constantly rotated in their respective operating directions by the gears 18 and 25 that are slightly meshed with the gears 19 and 26 of the reverse rotation rollers 10 and 20.

However, the normal rotation roller 10 and the normal rotation touch roller 1
6, since the convex portion of the cam 30 is not positioned to push down the trochanter 45, there is a gap that exceeds at least the thickness of the band-detector, and the band within the band shooter 1 is not affected. The same holds true for the relationship between the reversing roller 20 and the reversing touch roller 23.

Now, when the band tip pushes the operating piece 51 of the limit switch LSI provided at the end of the band guide 52, the camshaft 4 rotates and the band gripper 54 rises to grip the band tip. Since the cam 31 is also rotating at the same time, the operating rod 40' is pushed down via the trochanter 45', the arm rod 46', and the interlocking rod 41', and the eccentric shaft 24 rotates in an arc. The reversing touch roller 23 supported by the reversing roller 24 is pushed down and pressed against the reversing roller 20. At this time gear 2
6 and 25 are completely engaged (Fig. 3). Therefore, the band is pulled back by a pair of rotationally driven rollers 20 and 23, and when the band is tightened against the object to be packed to the set tightening torque by the tightening setting voltage of the electromagnetic clutch 60, it engages with the gear 22 of the reversing roller 20. The armature 65 slips against the rotary wheel 3 via the gear 15 on the shaft 11. That is, since the rotational speed of the reversing roller 20 decreases and eventually comes to a standstill, the shaft 21 and therefore the shaft 11
The armature 65, which was attracted to the rotor 64 by a certain magnetic force under the set voltage, slides against the magnetic force and stops the rotation of the pulley 13, which is the drive shaft, from the shaft 11.
The transmission stops.

At the time B, the rotation speed of the magnet 7 in the stop ring 6 provided at the end of the drive shaft 11 also decreases, and finally comes to a stop. Therefore, the rotation detection section 8 provided near the rotation locus of the magnet 7 detects that the number of rotations of the drive shaft 11, that is, the reversing roller 20 has decreased (reduction including stoppage), and generates a deviation detection signal. , the power supply to the coil of the electromagnetic clutch 60 is cut off, and power transmission to the drive shaft 11 is stopped. At this time, the tension applied to the already tightened band acts on the band to pull it back toward the reversing roller 20, but the shaft 21 of the reversing roller 20 is supported via a one-way clutch 34 so that it rotates only in the tightening direction. Then, the tightened band is fixed between both rollers 23 and 20. At the same time, the camshaft 4 is rotated by the detection signal, and the gripping means 55 on the band supply end side rises to grip and fix the band between it and the slide table 50 in a tightened state. Furthermore, due to the rotation of the camshaft B, the reversing touch roller 23 is separated from the reversing roller 20 due to the rotation of the cam 31.

When the reversing touch roller 23 separates from the reversing roller 20,
The band tension between the gripping mechanism 55 on the band supply end side and the reversing roller 20 is released, and the rotation of the camshaft 4 causes bonding between the band overlapping parts and positioning the band tip at the left end of the gripping mechanism 54. The band on the supply end side is cut. Then, due to the rotation of the camshaft 4, the arm rod 46 is rotated by the rotation of the cam 30 which presses the normal rotation touch roller 16 against the normal rotation roller 10, so that the operating piece is exposed to the tip of the arm rod 46. Limit switch (LS4) is O
At N, the electromagnetic clutch 5 is energized (voltage necessary for band feeding), the drive shaft 11 rotates, and the band is fed to the outside of the packaging machine body between the normal rotation roller 10 and the normal rotation touch roller 16.

The limit switch (LS4) is provided at the tip of the arm rod 46 in the same way as the limit switch at the tip of the arm rod 46', and the ON signal of the limit switch (LS4) turns on a separate timer, and after the set time elapses, the cam is turned on. Since the shaft 4 is rotated and the cam 30 is rotated, the normal rotation touch roller 16 is released from pressure contact with the normal rotation roller 1o. This completes the supply of a certain amount of bands. At this time, the limit switch (L
S4) is turned OFF, and in response to the signal B, the camshaft 4 is stopped and the electromagnetic clutch 60 is energized to the tightening set voltage. At this time, the voltage applied to the electromagnetic clutch is adjusted to the tightening setting voltage using a signal that does not have to be the tightening setting voltage to energize the electromagnetic clutch (limit switch 82 detects the rise of the band tip gripping mechanism 3). It is also possible to set it like this. When the camshaft 4 is stopped by turning off the LS4, the camshaft 4 completes one rotation of 360°.

As described above, the present invention includes a drive shaft that rotates at least the negative roller of a pair of rollers that rotate in opposite directions in synchronization with each other to pinch and tighten the packaging band.
A field core containing a built-in coil, a rotor that is wedged to the drive shaft and forms a magnetic pole together with the field core, an armature that is attracted to the friction plate of the rotor and generates torque, and a rotor that is interlocked with the armature and connected to the drive mechanism. Since the clutch is equipped with a rotatable drive shaft, and the locking member provided on the drive shaft or armature is inserted into the engagement portion formed on the drive shaft or armature, it is less expensive than the conventional friction type dry single disc clutch. While taking advantage of the advantages of The previously constant tightening torque has been made adjustable. When the band is tightened, after the rotation speed of the reversing roller decreases,
Until rotation is stopped and the tightening process is completed, it is possible to generate an appropriate slip between the rotor and armature of the electromagnetic clutch by applying a tightening torque higher than the set voltage to the cork, and the torque adjustment is possible. This makes it possible to provide an electromagnetic clutch for a band tightening device of a packaging machine that is extremely effective in practice and has the advantages of an expensive air-gap type electromagnetic clutch.

[Brief explanation of drawings]

Figure 1 shows one embodiment of the present invention.
2 is a front view of essential parts, FIG. 3 is a plan view, and FIG. 4 is a sectional view taken along line IV-IV in FIG. 1. 11... Drive shaft 13... Driving shaft 60 Electromagnetic clutch 63 - Field core 64 - Rotor 65 - Armature 66 - Locking member 67 - Engagement part Patent Applicant Patent attorney representing STRAPAC Shimojima Co., Ltd. Small Masaaki Kura Diagram 4 Procedural Manual (spontaneous) May 17, 1980 Director-General of the Patent Office Mr. Kazuo Wakasugi1, Indication of the case 1982 Patent Application No. 260742, Name of the invention Packing machine bread 1 - an electromagnetic clutch 3 in a tightening device;
Relationship with the case of the person making the amendment Patent applicant address: 1-2-17 Higashi-Shinbashi, Minato-ku, Tokyo Name: Stravac Shimoshima Co., Ltd. 4, Agent: 105
Telephone (436) 2398 (principal) Statement 6, amendment to statement of contents M (no change in contents)

Claims (1)

[Claims] A field core with a built-in coil is mounted on a drive shaft that rotates at least the negative roller of a pair of rollers that rotate in opposite directions in synchronization to pinch and tighten the packaging band, and a field core that has a built-in coil and a wedge attached to the drive shaft. A rotor that is attached to the rotor and forms a magnetic pole together with a field core, an armature that is attracted to a friction plate of the rotor and generates torque, and a rotatable driving wheel that interlocks with the armature and is connected to a drive mechanism. Alternatively, an electromagnetic clutch in a band tightening device for a packaging machine, characterized in that a driving wheel or a locking member provided on the armature is fitted into an engaging portion formed on the armature.