JPH07107215B2 - Rotor braking device - Google Patents

Description

Description: [Industrial field of application] The present invention relates to a braking device suitable for braking a warp beam or the like used in a woven process, for example.

[Prior Art] In the warp preparation step, which is one step of the woven process, as shown in FIG. 3, a plurality of warp beams 1, ... Are arranged in parallel, a creel 2, a sizing machine 3, and a drying machine. Cylinder rollers 4, ... Are provided, and the warp beam 1,
A large number of warp yarns 6 delivered from the ... are passed through the sizing tank 3a of the sizing machine to be glued, dried, and then wound on the loom beam 7. Warping beam 1 has
A braking device for braking the rotation of the beam is provided in order to adjust the tension of the unwound warp yarns 6, ... As a conventional braking device, there are the following two methods.

One is a collective braking system in which all the warp beams 1, ... Are simultaneously braked by a common brake belt 11 hung on the brake pulley 10 of each warp beam 1, as shown in FIG. In the illustrated example, the brake pulley 10 of each warp beam,
Brake belts 11 are alternately applied to, one end of which is fixed to a fixed point 12, the other end of which is a weight and an air cylinder 13
It is pulled by an urging means such as the above, and braking is applied by the frictional force between the brake pulley 10 and the brake belt 11.
In the case of this method, since the braking force of each warp beam is equalized, there is a problem that when the beams having different warp winding amounts and different payout radii of warp are simultaneously used, the tension of each warp varies. It was not suitable for a factory that handles a wide variety of products and small lots.

The other one, as shown in FIG. 6, is to individually brake each warp beam by tensioning a brake belt 15 applied independently for each brake pulley 10 of each warp beam with a weight 16 or the like. It is an independent braking system. According to this method, since the braking force of each warp beam can be adjusted individually, there is an advantage that beams having different warp winding amounts can be used at the same time.

[Problems to be Solved by the Invention] However, in the above conventional independent braking method, since the brake pulley 10 is directly braked by the brake belt 15, the warp threads 6, ... Are subjected to excessive tension or impact during operation. It was easy, and there was a risk that the warp threads 6 would break. Further, since the tension of the brake belt 15 is adjusted stepwise by a plurality of weights 16 having different weights, the fluctuation range of the tension in one step adjustment is large as shown in FIG. 4B, and the fine adjustment of the braking force is performed. Was difficult.

Further, in this type of device, the beam tends to overrun at the time of starting and stopping, so in order to prevent this, it is preferable to make the braking force comparatively large during low speed operation. Since the tension gradually increases as the diameter decreases, it is preferable to reduce the winding diameter as well as the braking force to prevent yarn breakage and winding disturbance.
In the conventional braking device described above, such adjustment of the braking force cannot be performed unless the operator takes extra effort to adjust the weight weight.

Then, this invention makes it a subject to solve the problem of the said conventional method.

[Means for Solving the Problems] In order to achieve the above objects, the present invention has the following configuration.

That is, the braking device for a rotating body according to the present invention includes a pulley having a common rotation center axis with the rotating body and rotating integrally with the rotation body, and swingable in a plane perpendicular to the rotation center axis. A lever having a plurality of engaging grooves formed at appropriate intervals on the upper surface thereof, a brake drum non-rotatably attached to the lever, and an endless loop hung between the pulley and the brake drum. A brake belt and a weight that can be selectively engaged with any of the plurality of grooves of the lever to be suspended can be provided.

[Operation] By suspending the weight in any of the multiple grooves provided on the upper surface of the lever swingably supported, a downward force acts on the lever, and the lever is attached so that it cannot rotate. An endless brake belt that is hung between the brake drum and the pulley is tightened. For this reason,
The rotation of the pulley is braked by the frictional force between the brake drum and the brake belt, and the braking force acts on the rotating body. Since this braking force changes depending on the suspending position of the weight, an appropriate braking force can be obtained by selecting a groove for suspending this.

Since the lever can swing in a plane perpendicular to the rotation center axis of the pulley, when the rotation speed of the rotating body becomes high, the brake belt bulges outward and the brake drum is pulled toward the pulley side. The length of the sliding contact portion between the belt and the brake drum is reduced, and the frictional force is reduced. For this reason,
In steady operation, the braking force is smaller than when starting or stopping. The brake belt largely bulges toward the feeding side (the side from the pulley toward the brake drum).

Further, if an impact force is applied to the yarn during operation for some reason, the lever automatically swings toward the pulley to temporarily reduce the braking force, and the control force is impacted.

[Embodiment] FIG. 1 shows a braking device for a warped beam which is an embodiment of the present invention. In the warping beam 1 which is a rotating body, a plurality of warp threads 6, ... Are wound up on a winding portion 21 formed between a pair of flanges 20,20, and horizontally project from both flanges 20,20. A central shaft 22 is rotatably supported by a bearing (not shown). As the braking device A, a pulley having a central axis 22 and an axis centered on the outer surface of one flange 20 is used.
25 is attached, and a fulcrum is provided below the pulley 25.
A brake drum 29 is non-rotatably attached to an intermediate portion of a lever 27 which is vertically swingable around a center 26, and an endless brake belt 30 is hung between the pulley 25 and the brake drum 29. The diameter D _{1 of the} pulley 25 is difficult to change because it is limited by the diameter of the warp beam attachment chuck of the winder, but the diameter D ₂ of the brake drum 29 can be set arbitrarily. In practice, it is preferable to set D ₁ = 214φ and D ₂ = 70φ so that D ₂ <D ₁ . The brake belt 30 is a belt-shaped belt made of leather, fabric, rubber or the like and having an appropriate friction coefficient. A plurality of grooves are formed at a predetermined interval on the tip of the upper surface of the lever 27.
32 are formed, and a weight 33 having an appropriate weight can be locked and suspended in any of these grooves. Weight 33 is lever 27 pulley 25
Is a biasing means for biasing in the opposite direction, that is, downward,
Other means such as a spring may be used as the biasing means.

When the operation of the warp preparation step shown in FIG. 3 above is started,
From each warp beam 1, ...
At this time, a rotation braking force acts on the warping beam 1 by the braking device A, and the tension of the warped yarns 6, ... This rotational braking force is mainly due to the frictional force between the brake drum 29 and the brake belt 30.
It is determined by D ₂ , the brake belt tension T, the coefficient of dynamic friction μ between the drum and the brake belt, and the like. As mentioned above, D ₁ > D ₂
Therefore, since the frictional force between the pulley 25 and the brake belt 30 is larger than the frictional force between the brake drum 29 and the brake belt 30, the movement of the brake belt 30 is controlled by the pulley 25, and the brake belt 30 and the brake drum 29 are moved. Keeps slipping at the sliding contact part. The dynamic friction resistance at this time becomes the braking force of the warp beam 1. The tension T of the brake belt 30 correlates with the force F that pulls the brake drum 29 downward, and the distance from the fulcrum 26 to the brake drum is R, the distance from the fulcrum 26 to the weight 33 is L, and the weight 33.
When the weight of is defined as W, there is a relation of F = (R / L) W.

The first advantage of the braking device A is that it is easy to finely adjust the braking force. To adjust the braking force, the suspension position of the weight 33 may be changed to change the distance L or the weight W of the weight 33 may be changed. By properly combining the two, the fluctuation range of the braking force is small. Adjustments can be made. FIG. 4 is a diagram showing the warp tension when the conventional braking device B is used and when the braking device A is used, and t ₁ is the minimum tension value at which the warp wound on the warp beam does not loosen. , T ₂ are the maximum tension values at which the weakest part of the warp is not cut. The conventional braking device B is
Since the fluctuation range of the warp tension per step is large, the warp tension t can only be adjusted to a desired value. On the other hand, in the braking device A of the present invention, since the fluctuation range of the warp tension t is small, it is possible to adjust to the optimum warp tension according to the type of the warp to be used, the count and the like.

The second advantage is that the buffering effect is large. Belt reliefs are provided at two locations, the brake belt 30 and the brake drum 29, and the brake belt 30 and the pulley 25, and the lever 27 resists the load of the weight 33.
Is capable of swinging in the opposite direction, and when a large load is applied, it is absorbed by these portions, so that cutting due to accidental tension fluctuation of the warp can be prevented in advance.

A third advantage is that the braking force automatically decreases as the rotational speed of the warping beam 1 that is a rotating body increases. FIG. 2 is an explanatory view thereof, and at low speed, the brake belt 30 is stretched substantially evenly as shown in FIG. 2A, but at high speed, as shown in FIG.
Swells to the downstream side of the pulley 25, the contact area between the brake drum 29 and the brake belt 30 becomes small, and the braking force decreases. Tables 1 and 2 show the experimental results of measuring the tension of the warp at low speed and high speed. Table 1 is the experimental result of the conventional braking device B, and Table 2 is the braking device according to the present invention. It is an experimental result of A. In the conventional case, even if the weight is the same, the warp tension increases as the rotation speed increases due to the decrease in the winding diameter, and thus the warp breakage easily occurs. On the other hand, in the case of the present invention, as the yarn speed increases, the warp tension decreases, and warp breakage is less likely to occur.

[Effects of the Invention] As is apparent from the above description, the braking device for a rotating body according to the present invention makes it possible to easily obtain a preferable braking force according to the rotation speed, and at the same time, a buffering effect at the time of load fluctuation. In addition, the fine adjustment of the braking force is easy, and the practical effect is high in the processes such as spinning and woven fabric.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an embodiment of a braking device according to the present invention,
2 (a) and 2 (b) are front views showing different states thereof, FIG. 3 is an explanatory view of a warp preparation process in a weaving process, FIG. 4 is a view showing a relationship between a load and a warp tension,
FIG. 5 is an illustration of the collective braking system, and FIG. 6 is an illustration of the independent braking system. 1 ... warp beam, 6 ... warp, 22 ... central axis, 25 ...
Pulley, 26 ... fulcrum, 27 ... lever, 29 ... brake drum, 30 ... brake belt, 33 ... weight (biasing means).

Claims (1)

[Claims] 1. A pulley that has a common rotation center axis with a rotating body and rotates integrally with the rotating body, and is pivotally supported up and down in a plane perpendicular to the rotating center axis and has an upper surface. A lever having a plurality of engaging grooves formed at appropriate intervals, a brake drum non-rotatably attached to the lever, an endless brake belt hung between the pulley and the brake drum, and the lever. And a weight that can be selectively engaged with any of the plurality of grooves to be suspended.