JPH01313005A - Manufacture of toothbrush - Google Patents

Abstract

PURPOSE:To easily manufacture a toothbrush having a ball like object on each of its hair tips by means of a simple additional device by blowing a hot air to the tip of the hair of each bristle of a toothbrush manufactured through a series of manufacturing processes for a constant period of time so as to melt the tip of the hair and forming a ball like object on the tip of each hair. CONSTITUTION:After bristles 7 are set on a brush stand, hairs are cut to level their hights, then the tip of each bristle is rounded by an abrasive plate, etc. A toothbrush which is finished in its tip rounding process is transferred by a transfer conveyer 1, in a hot air blowing process d provided on the same stage. This transfer is performed intermittently at an constant pitch interval and a toothbrush is correctly positioned under the hot air blowing equipment 5. Blowing of a hot air is controlled in connection with the intermittent transfer of the transfer conveyer and hot air temperature, blowing amount of hot air and time of blow are strictly controlled. When hot air is forced to blow the tip of hair surface of each bristle, the tip melts and molten ball is formed on the hair tip by surface tention. Next, cool air is forced to blow, from cool air nozzle 13, to the tip and the molten ball is hardened to form a ball like object.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method of manufacturing a toothbrush having spherical objects at the bristles.

[Conventional technology]

In addition to the toothbrush's inherent cleaning effect on tooth surfaces and interdental areas, the technology of providing spherical objects on the tips of the bristles in order to enhance the pine surge effect on the gums is already well known.For example, such a toothbrush Applications have been filed such as Utility Model Application No. 171938/1983 and Utility Model Application No. 61-97923.

For example, the following method is known as a method for manufacturing a toothbrush having spherical objects on the bristles.

That is, the bristles, which have been trimmed to the same length, are fed one by one onto a transfer conveyor, and the bristles are transferred along the flow of the transfer conveyor, and flames are applied to both ends of the bristles from both sides of the conveyor to separate the bristles. The tips are melted to make a spherical object.Next, after bundling a certain number of bristles with spherical objects formed therein, the bristles are bent at the center in the length direction and placed on a brush stand to complete the toothbrush.

[Problem to be solved by the invention]

However, in the above manufacturing method, it is necessary to first break apart the bristles supplied in a bundle, form spherical objects at both ends, and then re-bundle the bristles and place them on the brush stand. There is a problem that the process becomes extremely complicated. Since the above process is significantly different from the conventional toothbrush manufacturing process, it is not possible to follow the conventional toothbrush manufacturing process as it is, and it is necessary to introduce new equipment for all processes in manufacturing this toothbrush.

Furthermore, manufacturing a toothbrush by the above method requires more time than conventional toothbrushes, and there is also the problem that productivity is low.

[Means to solve the problem]

The present invention has been made in view of the current situation, and it is possible to manufacture a toothbrush with spherical objects on the bristles by following the conventional toothbrush manufacturing process and adding a simple device to the conventional equipment. It is an object of the present invention to provide a method for manufacturing a toothbrush which is also excellent in productivity.

The gist of the present invention, which has achieved such problems, is to include a hair transplanting process for implanting bristles in a brush stand, a hair cutting process for aligning the height of the tips of the bristles planted in the brush stand, and a hair transplanting process for planting bristles on the brush stand. The bristle tips of toothbrushes, which are produced through a series of manufacturing processes that include a rounding process to round the tip, are characterized by blowing hot air for a certain period of time to melt the bristles and form a spherical substance at the tips. shall be.

It is preferable that hot air be blown from a direction opposite to the tip surface of the bristles.

In addition, the temperature, air volume, and blowing time of the hot air are set to be higher than the melting point temperature of the synthetic resin constituting the bristles and below 400°C, and the air volume is set to 0.1 nf/win ~ 0.6nf/+++in,
The wind speed was set within the range of 3.4 m/s to 20 m/s, and the blowing time was set to 0.05 sec to 0.00 m/s.
It is preferable to set it to 5 seconds.

Further, in order to prevent the molten hair ends from fusing together, a hair handling process may be provided as appropriate following the hot air blowing process.

In addition, in order to prevent the molten hair tips from welding and to make the shape of the spherical object closer to that of a pearl, when blowing hot air, each bristle is charged to the same polarity, and the bristle and the hot air nozzle are charged to the same polarity. It is desirable to charge the polarity.

[For production]

In this method of manufacturing a toothbrush, the conventional toothbrush manufacturing process is followed up to the hair flocking process, hair cutting process, and tip rounding process, and hot air is applied to the bristle tips of the toothbrush manufactured through the above manufacturing process. By spraying for a certain period of time, the tips of the hair are melted and a spherical substance is formed on the tips of the hair.

When hot air is blown from the direction opposite to the tip of the bristles, the hot air is blown almost uniformly over the entire tip of each bristle, making the size of the spherical objects formed on the tips of the bristles uniform. Easy to do.

When a bristling step is added following the hot air blowing step, even if there are welded bristles, the bristles are separated by the bristling, so it is possible to eliminate the occurrence of defective products.

Also, when the bristles are charged to the same polarity and the bristles and the hot air nozzle are charged to different polarities, since the bristles are of the same polarity, they repel each other and try to separate, resulting in the molten balls being adjacent to each other. Since there is no longer any welding with the molten balls, relatively large spherical objects can be formed. Furthermore, since each molten ball is pulled in the direction of the hot air nozzle having a different polarity, deformation of the molten ball, which tends to become flat due to the pressure of the hot air, can be suppressed.

〔Example〕

Next, details of the present invention will be explained based on illustrated embodiments.

FIG. 1 is a process explanatory diagram showing one embodiment of the method for manufacturing a toothbrush according to the present invention. The example shown in FIG. Hair cutting step 1 Rounding the tip of the bristle after cutting with a polisher C1 Hot air blowing step d where hot air is blown onto the tip of the bristle after rounding to form a molten ball on the tip , by blowing cooling air onto the molten ball,
The stages from the hair cutting process to the hair handling process f are the same, consisting of a cold air blowing process e that promotes hardening of the molten ball, and a hair handling process f that separates the welded bristles by handling the tips of the cooled and hardened bristles. The same conveyor conveyor is used to transfer between each process. In the above manufacturing process, the hair flocking process a, the hair cutting process S, and the tip rounding process C follow the conventional toothbrush manufacturing process as they are. The hot air blowing step d, the cold air blowing step e, and the bristle handling step f are the steps added in the present invention, and the details of these steps d, e, and f are shown in FIG. The toothbrush 2 is fixedly arranged on the transfer conveyor 1 with the bristles facing upward, for example, by means of a holding means 3. The transfer conveyor 1 is fed at a predetermined pitch, and is configured to be able to intermittently transfer the toothbrush 2 one after another, for example, from a stop position X to a stop position Y. A hot air blowing device W5 with a hot air nozzle 4 directed downward, spaced a certain distance above the stopping position WX.
is positioned. The blowing of hot air from the hot air blowing device 5 is performed in conjunction with the intermittent movement of the transfer conveyor 1, and is performed when the toothbrush 2 is transferred to a position below the hot air nozzle 4 and stopped. Further, a shutter device 6 is interposed between the hot air nozzle 4 and the toothbrush 2.

This shutter device controls the passage time of the hot air intermittently jetted from the hot air nozzle by opening and closing,
The hot air blowing time to the bristles 7 is strictly adjusted, and its structure is, for example, as shown in FIG. A configuration is adopted in which the opening 8 is closed or opened by moving the slide plate 11 relative to the opening 8.

The direction in which the hot air is blown is not limited to that shown in the illustration, but if the purpose is to form a more uniform spherical object at the tip of the bristles 7, the direction in which the hot air is blown is above the planting of the bristles as shown in the figure, and toward the tips of the bristles. It is preferable to perform this from the direction facing the surface.

A cold air blowing device 12 is disposed on the side of the hot air blowing device 5 with a cold air nozzle 13 at its tip facing toward the bristles 7. In the illustrated example, the cold air is blown from diagonally above the bristles 7, but this can also be done from the side of the bristle 7, or by moving the transfer conveyor forward one pitch as shown in FIG. The cold air blowing device 12 may be configured to blow from vertically above the toothbrush 2 at the stop position after the toothbrush 2 has been heated.The cold air blowing device 12 is controlled in conjunction with the hot air blowing device 5, and the timing of blowing the cold air is immediately after the hot air stops blowing. It is set to take place on. The purpose of blowing cold air is to rapidly cool the molten ball, thereby stabilizing the spherical shape at an early stage, preventing the molten ball from becoming deformed due to liquid shaking, and shortening the processing time by speeding up hardening. Although this step is to increase productivity, this step is not necessarily necessary and can be omitted as appropriate.

A rotating brush 14 for brush handling is arranged above the next stop position WY, which is a certain distance away from the stop position X.

The rotating brush 14 has a structure in which a comb-shaped member 16 is provided around a rotary body 15, and by rotating the comb-shaped member 16 and brushing the bristles 7, it serves to separate the welded bristles from each other.

In order to manufacture a toothbrush having spherical objects at the tips of the bristles using the method for manufacturing a toothbrush having such a configuration, the following steps are performed. First, the bristles are planted on the brush stand, the bristles are trimmed to make the height of the bristles even, and then the tips of the bristles are rounded using a polishing plate or the like. The steps up to this point are all the same as the conventional toothbrush manufacturing process, and the device can follow the conventional device as it is.The following steps are added in the present invention.

That is, the toothbrush that has been processed is transferred by the transfer conveyor 1 to the hot air blowing step d arranged on the same stage. This transfer is performed intermittently at regular pitch intervals, and the toothbrush after being moved is accurately positioned at the processing position in each processing step.

In this way, hot air is blown onto the toothbrush correctly positioned below the hot air blowing device 5. The hot air blowing is controlled in conjunction with the intermittent transfer of the transfer conveyor, and the hot air temperature, hot air blowing amount, and blowing time are strictly controlled. A shutter 6 interposed between the hot air nozzle 4 and the toothbrush allows or prohibits the passage of the hot air jetted from the hot air nozzle 4 and attempting to reach the bristles 7 by opening and closing the shutter 6. The hot air blowing time, which has already been adjusted to some extent, is now more strictly controlled. Hot air is blown onto the tip surface of the bristles, and as a result, the bristle tips melt and molten beads are formed on the bristle tips due to surface tension.Next, cold air is blown from the cold air nozzle 13, and the molten beads harden. It becomes a spherical object. In this example, the hot air blowing time was controlled by adjusting the opening and closing of the shutter 6, but it was also possible to adjust the stopping time of the toothbrush, which is stopped below the hot air nozzle, without using the shutter, or to stop the toothbrush. The hot air may be passed under the hot air nozzle at a constant speed without moving, and the hot air blowing time may be controlled by adjusting the moving speed at the time of passing.

As long as the temperature, air volume, and blowing time of the hot air are strictly controlled, the molten ball will grow to its maximum size without welding to adjacent molten balls, but in some cases the molten ball may grow too much. It may be deformed, and in this case, adjacent molten balls may be welded together. These welded bristles are separated by a bristling treatment in the next step, and become independent normal bristles.

What is shown in FIG. 4 is another embodiment of the present invention.

In the above-mentioned embodiment, the conventional process consisting of the hair transplanting process 81, the hair cutting process b, and the tip rounding process C, the hot air blowing process d, the cold air blowing process e, and the hair handling process f are arranged in the same stage, and the time between each process is This was a case in which the processes from flocking to hair sorting were performed online as a series of operations connected by a transfer conveyor, but this example consists of a hot air blowing process dr, a cold air blowing process e', and a hair sorting process f'. The additional process is configured independently from the conventional process, and a toothbrush produced using an existing conventional device is separately supplied to the hot air blowing process d' by an appropriate means, and a toothbrush having spherical objects at the bristles is produced by off-line processing. This is what I am trying to do. According to this method, only the additional processes consisting of a hot air blowing process, a cold air blowing process, and a hair cutting process need to be newly installed, so there is no need to make any changes to conventional equipment. Less capital investment is required for manufacturing.

What is shown in FIG. 5 is an embodiment that is appropriately added to the hot air blowing process. As mentioned above, adjacent bristles may be welded together when blowing hot air, but
As shown in the figure, if the bristles are charged to the same polarity and the bristles and the hot air nozzle are charged to different polarities, the adjacent bristles will electrically repel each other and try to separate, resulting in welding of the bristles. The fear can be reduced. Since the distance between the bristles can be increased, the maximum diameter of the formed spherical object can also be increased. Furthermore, due to the stretching direction of the synthetic resin material that forms the bristles and the influence of wind pressure, the molten balls formed at the ends of the hair tend to have a flat shape, but if the bristles and the hot air nozzle are charged with different polarities. Since the molten ball is pulled upward by the electric attractive force, it is possible to prevent the spherical object from becoming flat.

Next, the inventor changed the hot air treatment conditions such as hot air temperature, air volume, and blowing time to increase the size of the spherical objects formed.
We investigated the shape and found preferable processing conditions. As a result, if the hot air temperature is lower than the melting point of the bristle material, it will not melt, and if it is too high, the molten ball will become too large and adjacent bristles will weld together. For example, in the case of nylon bristles, 230℃~
Set within the range of 400℃, and further 260℃~320'
It was found that it is more preferable to set it within the range of C. In addition, since wind speed acts as wind pressure, it becomes a determining factor for the shape of the spherical object. As a result of the experiment, the wind speed was 3°4m/s
The range of ~20m/s is preferable, and more preferably the range of ~20m/s ~17cm
It is more desirable to set it to /S.

Air volume and spraying time have a contradictory relationship; if the spraying time is short, the air volume needs to be increased.

Since the reduction in spraying time is directly reflected in the reduction in time in the toothbrush processing process, from the viewpoint of improving productivity, it is ideal that the spraying time is shorter. However, since the minimum value of the spraying time depends on the opening/closing speed of the shutter 6, the spraying time is usually within the range of 0.05 sec to 0.5 sec, preferably 0.07 sec' to 0°2 sec.
It is desirable to set the air volume to 0.1rr.
f/sin ~0.6rrf/sin, preferably 0
．． 3rrr/akin ~0.5rd/wi
It is desirable to set it in the range of n.

Figure 6 (a) shows the toothbrush before hot air treatment, and Figure 6 (b) and (c) show the finished state of the spherical toothbrushes treated with hot air under different hot air treatment conditions. Nylon bristle is implanted with the same hair length. For the toothbrushes shown in Fig. 6 (b) and (c), the hot air temperature is 260°C to 320°C, and the blowing time is 0.07 sec to 320°C.
This is the result of hot air treatment with the air volume set within the range of 0.2 sec.
Po/sin~0.6i/■in, wind speed 14m/s
These are the processing results when the speed was set to ~20 m/s (processing condition 1). On the other hand, what is shown in Fig. 6 (c) is the processing result when the air volume was set to 0.2nf/sin -0.4nf/sin and the wind speed was set within the range of 7 m/s x 14 m/s (processing condition 2). It is.

As a result, under treatment condition 1, the spherical objects formed at the tip of the bristle are small, uniform in diameter, and have the same hair length, whereas under treatment condition 2, the spherical diameters are uneven; It was also found that the length of the hair was uneven, with a mountain-cut shape. Therefore, it can be seen that various types of toothbrushes can be obtained simply by considering the hot air treatment conditions. In addition, a toothbrush with a small and uniform ball diameter does not feel like a foreign body when using it.
In addition, it is possible to effectively remove plaque accumulated between teeth.On the other hand, toothbrushes with uneven ball diameters and uneven bristles,
It is possible to obtain a toothbrush that has an excellent pine surge effect and can deal with various stains on tooth surfaces and between teeth.

Figure 7 shows the external appearance of a spherical object created by the method of the present invention.In the present invention, hot air is used as a heating means for the bristle, so in addition to the wind pressure acting on the molten ball, the nylon bristle Due to the influence of the stretching direction, the formed spherical object always has an elliptical shape in a projection view that is flat in the length direction of the bristles. <Table> shows the variation in the shape of spherical objects when spherical objects were formed under the processing conditions 1. A, B, and C in the table are respectively A, B, and C as shown in FIG. is the length of the ellipse in the longitudinal direction, B is the length of the ellipse in the short direction, and C is the diameter of the bristle, and all units are in confidence. n is the number of samples, and ma is the average value. The bristle used for measurement was a nylon bristle manufactured by DuPont, USA, with a diameter of 8 ail (
~0.203mm) and 1(lsil(・0.25mm)
According to the toothbrush manufacturing method according to the present invention as described above, a hot air blowing process etc. is added following the conventional process without changing the conventional toothbrush manufacturing process. You can easily obtain a toothbrush with spherical objects formed on the tips of the bristles. Since the size of the spherical objects, the length of the bristles, etc. can be freely changed by simply changing the hot air conditions, toothbrushes of various types can be obtained using the same equipment. Further, in this embodiment, since the hardening of the molten ball is accelerated by blowing cold air, productivity is high and welding of adjacent bristles can be reduced. Furthermore, in this embodiment, the bristles can be separated even if adjacent bristles are fused together, since the bristles are separated after the cold air blowing step.

In addition, in the hot air blowing process, when the bristles are charged to the same polarity and the bristles and the hot air nozzle are charged to different polarities, the bristles electrically repel each other and try to increase the gap between the bristles. Even when a molten ball with a relatively large spherical diameter is formed, the molten ball will not be welded, and since an electrical attraction force acts between the bristle and the hot air nozzle, the effect of wind pressure and the stretching direction of the nylon bristle will prevent the molten ball from welding. A spherical object can be made closer to a true spherical shape by suppressing the tendency to take on a circular shape when viewed by projection.

〔Effect of the invention〕

The method for manufacturing a toothbrush according to the present invention includes a hot air blowing process following the conventional toothbrush manufacturing process, flocking processing,
By blowing hot air onto the bristles of the toothbrush after hair cutting and cutting, a spherical object was formed at the tip of the bristle, making it possible to use conventional equipment as a roadbed. It is possible to easily produce a toothbrush formed into an object.

Moreover, since the additional hot air blowing work is completed in a short time, the production efficiency of toothbrushes is not reduced, and useful toothbrushes can be provided at low cost.

Further, when the bristles are separated after the hot air blowing step as in the fourth aspect, even if adjacent bristles are welded together, they can be separated, thereby preventing the production of defective products.

Furthermore, as stated in claim 5, when the bristles are charged to the same polarity when hot air is blown, and the bristles and the hot air nozzle are charged to different polarities, the bristles electrically repel each other. The phenomenon of welding between them is reduced, and relatively large spherical objects can be formed.

Since the bristles and the hot air nozzle are charged with different polarities, an electrical attractive force acts between them, making it possible to transform a spherical object that tends to have a circular shape when viewed by projection into a true sphere.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing an overview of a manufacturing apparatus that implements the toothbrush manufacturing method according to the present invention, FIG. 2 is an explanatory diagram of the main parts of the same manufacturing apparatus, FIG. 3 is an explanatory diagram of the shutter mechanism, and FIG. 4 ,
Fig. 5 is another embodiment of the manufacturing device, Fig. 6 (a) is an enlarged explanatory view of the main parts showing the state of the toothbrush before hot air treatment, Fig. 6 (
b) (c) are enlarged explanatory views of main parts showing the state of the toothbrush after hot air treatment, and Fig. 7 is an explanatory view showing the projected shape of the spherical object. &: Hair transplanting process, b: Hair cutting process, C: Tip rounding process, d:
Hot air blowing step, e: Cold air blowing step, f: Hair handling step, 1: Transfer conveyor, 2: Toothbrush, 3: Holding means, 4;
Hot air nozzle, 5: Hot air blowing device, 6: Shutter, 7:
Bristle, 8: Opening, 9: Fixed plate, 10: Opening, 11
varnished plate, 12: cold air blower, 13: cold air nozzle, 14: rotating brush, 15: rotating body, 16: L-shaped member. Figure 2 d Figure 1 a OC Figure S (A) c0 F (C)

Claims (1)

[Scope of Claims] 1) A hair transplanting step of planting bristles on the brush stand, a hair cutting step of making the height of the tips of the bristles that are planted on the brush stand even, and a tip rounding of the tips of the cut bristles. A method for manufacturing a toothbrush, which is produced by blowing hot air onto the bristle bristles of a toothbrush produced through a series of manufacturing steps including processing steps, for a certain period of time to melt the bristles and form spherical objects at the bristles. 2) The method for manufacturing a toothbrush according to claim 1, wherein the hot air is blown from a direction opposite to the bristle tip surface of the bristles. 3) The temperature of the hot air is at least above the melting point of the bristles and below 400 degrees Celsius, and the air volume is 0.
．． 1m^3/min ~ 0.6m^3/min, wind speed is 3
．． 3. The method of manufacturing a toothbrush according to claim 2, wherein the blowing time of the hot air is set in the range of 4 m/s to 20 m/s, and the blowing time of the hot air is set in the range of 0.05 sec to 0.5 sec. 4) The method for manufacturing a toothbrush according to claim 1, 2, or 3, wherein a bristle handling step is added following the hot air blowing step. 5) When blowing hot air, the bristles are charged to the same polarity, and the bristles and the hot air nozzle are charged to different polarities. manufacturing method for toothbrushes.