JPH0818754B2 - Traverse drum manufacturing method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a traverse drum used in an automatic winder for winding various yarns, and more particularly to a method for manufacturing the drum by precision casting.

[0002]

2. Description of the Related Art A traverse drum having a spiral endless groove for guiding and traversing a yarn is essential when winding various yarns other than spun yarn into a bobbin shape or a cheese shape at high speed. Is. In recent years, in response to the demand for higher efficiency in the textile industry, the winding speed is increasing more and more. Therefore, the friction of the drum groove, which is in contact with the high-speed yarn for a long time, is becoming a more serious problem.
Furthermore, weight reduction of the drum is also a very important prerequisite for high-accuracy high-speed rotation.

The traverse drum made of aluminum alloy is light in weight, but has insufficient abrasion resistance. On the other hand, the traverse drum made of iron-based alloy is excellent not only in wear resistance but also in antistatic property, but has a specific gravity about three times that of aluminum, and in order to meet the demand for weight reduction, It is necessary to have a wall thickness of 3 or less.

In view of such a situation, the inventor of the present invention has already proposed a traverse drum made by precision casting to reduce the thickness and weight of the traverse drum made of an iron-based alloy, and a method for manufacturing the traverse drum. 61-69670).

[0005]

However, in the above-mentioned conventional method, it is necessary to increase the draft angle with respect to the groove at the time of molding the model, and a soluble wax having a large coefficient of thermal expansion and a poor mechanical strength is used. Since a product (that is, a model) is manufactured, the width of the groove for guiding the yarn cannot be set to a narrow groove width for satisfying the winding condition. It has been found that there is a problem in that, for example, ribbon winding is likely to occur. In addition, since the core is composed of soluble urea resin or the like, the effluent solution must be treated, and the pollution control cost becomes a big problem as well as the production increase.

Therefore, the present invention does not use a core at all, and the model is a synthetic resin excellent in dimensional stability and mechanical strength,
For example, we provide a method of precision casting a traverse drum made of iron-based alloy that is thin and thin and lightweight by molding it with urea resin that has low thermal expansion and low melting point and uses this to reduce the draft of the groove. The purpose is to do.

[0007]

In order to achieve the above object, the present invention makes a model of a soluble material, soaks it in a mold material, removes the model to make it hollow, and melts it into this cavity. In the casting method of casting a metal into a product, a synthetic resin is used as the soluble material, and two thin hollow half models having a shape divided into two in the axial direction of the traverse drum are molded in a mold. The two half-models are joined with an adhesive to form the above model, and the operation of dipping the model into the refractory slurry of the mold material, pulling it up, and drying it is repeated, and the fire resistance that adheres to the inner and outer surfaces of the model is generated. After the material layer reaches the required thickness, a hollow mold is produced by pyrolyzing and removing the model sandwiched between the refractory material layers when firing the refractory material layer, and then pouring. Each process such as hot water and post-treatment And performing casting operations.

According to the method of the present invention, each of the half-models made of the synthetic resin is molded by a mold having a multi-divided structure, and the joining operation is performed on the inner peripheral surface of the semi-model which is in close contact with the outer peripheral surface. It is one of the very important requirements to carry out the operation in the adhesive jig which is divided into two and which can be opened and closed. Another requirement is to use a urea resin having a low coefficient of thermal expansion as the synthetic resin.

[0009]

The above mold for molding a half model is composed of a male mold and a female mold. These molds are assembled by assembling a plurality of mold parts axially divided so as to have a semicylindrical shape as a whole. A void to be constructed and filled with synthetic resin is formed between male and female molds for use. When the synthetic resin is urea resin,
The voids are filled with the prepolymer powder, compression molding is performed, and after the resin is cooled, the female mold is removed in the centrifugal direction, and the male mold is removed in the centripetal direction.

Further, since a soluble core is not used, therefore, as in the conventional case, a female mold is formed with a space around the core, which has poor dimensional stability and is likely to be partially deformed or damaged during handling. Since it is not necessary to perform the difficult operation of arranging, the method of the present invention can accurately form a void having a predetermined size. Therefore, the thickness of the model directly manufactured by using a synthetic resin having a good dimensional stability and mechanical strength without a core can be made sufficiently thin, and the dimensional accuracy is also excellent. Moreover, the groove width of the groove portion formed in the peripheral surface of the model, that is, the concave portion serving as the yarn guide guide in the traverse drum after finishing can be sufficiently narrowed under the molding conditions.

When joining the two half models, the above-mentioned 2
In the case of using a split open / close type jig, by bringing the outer peripheral surface of the half model into close contact with the inner peripheral surface of the jig, there is no risk of relative displacement between the two butted half models.
In any of the cross sections, they are joined in the state of forming a perfect circle.

As described above, the refractory layer is formed on both the inner and outer surfaces of the thus-prepared frustoconical or cylindrical thin-walled hollow half-model, and the firing temperature of the refractory layer is an organic substance. It is much higher than the contact temperature of the synthetic resin such as urea resin. Therefore, since the model can be automatically removed at the same time as the firing, the wax-leaching operation before firing by the autoclave as in the prior art is unnecessary.

[0013]

Embodiments of the present invention will be described below with reference to the drawings, but the method of the present invention is not limited to the embodiments.

First, the traverse drum 1 after completion will be briefly described with reference to FIG. 1. The drum portion 1 traverses a cylindrical portion 3 having an outer peripheral surface in which a yarn guide groove 2 is formed in a spiral shape and endlessly. While abutting on the peripheral surface of a bobbin or the like that is being wound up. The drum is supported indirectly or directly by a drive shaft 6 via a large-diameter side cover 4 and a small-diameter side cover 5 whose both end surfaces are closed. These covers 4 and 5 are respectively screwed into screw holes 7 on the drum end surface.
The bearing 9 rotatably supports the cylindrical body 8 to the portion of the drive shaft 6 on the large diameter side of the drum, and the bearings 11 and 12 rotatably support the housing 10 fitted on the cylindrical body 8. It is a thing. That is, the drum 1 which receives the driving force on the small diameter side is rotatably supported on the driving shaft 6 via the housing 10 and the cylindrical body 8 on the large diameter side.

The traverse drum 1 manufactured by the method of the present invention has, for example, a diameter (d) of about 90 mm, a length (l) of about 150 mm, and a thickness (t) of the cylindrical portion 3 of about 1.
It is 0 to 2.0 mm, the included angle α of the side wall surfaces of the yarn guiding groove 2 is about 5 °, and the width of the groove 2 is about 3 m on the outside.
It has become m. The drum 1 of this specification weighs about 1.
It is 2 kg. On the other hand, in the drum 1A according to the conventional method shown in FIG. 11 (the method described in the above-mentioned JP-A-61-69670), the thickness of the cylindrical portion 3A is about 1.
5 to 2.5 mm, the included angle β of the side wall surfaces of the yarn guiding groove 2A facing each other is about 15 °, the width of the groove is about 5 mm on the outside, and the drum weight is about 1.5 kg.

Next, referring to FIG. 2, the method of the present invention will be described in the order of steps. First, a half-model forming step A is performed to form the right half half-model 20A and the left half half-model 20B by compression molding of urea resin (urea resin), the details of which will be described later with reference to FIGS. . Next, a model assembling step B is performed, and the two half models 20A and 20B are bonded and integrated to form a hollow truncated cone model 21. The details are also as described later with reference to FIGS. 7 and 8. Further, in the next mold making process C, a short cylindrical urea resin sprue 22 is concentrically attached to the small-diameter side end of the model 21, and dipping, pulling and drying into the slurry of the refractory material 23a are repeated a required number of times. After carrying out to form the refractory material layer 23, it is fired to remove the portion of the model 21 and the gate 22 made of urea resin by thermal decomposition to form a mold 24.
This will be described later with reference to FIG.

In the next pouring step D, the molten metal 25 (for example, superalloy steel) is cast into the void portion of the urea resin removal trace of the mold 24 under a vacuum or a high reduced pressure. The details will be described later with reference to FIG.

Among these processes, the half-model forming process A,
The model assembling step B and the mold making step C are the features of the method of the present invention, and the pouring step D is a step devised as described later in the present embodiment, but the slow cooling step after that. E and the take-out and post-treatment step F may be carried out according to a conventionally known precision casting method, and may be carried out by appropriately selecting a titanium nitride coating or the like for increasing the hardness of the drum surface and imparting wear resistance.

The steps unique to the present invention and the examples will be described below. As shown in FIGS. 3 and 4, in the half-model forming step A, a male part 30 composed of multi-divided male parts 30a, 30b, 30c to form a thick semi-cylindrical shape as a whole and the hollow part The central extraction rod 36 that fills the core portion is set on the base 34. The female die 3 is spaced from the outer peripheral surface of the male die 30 by a predetermined distance K, for example, about 1.5 mm.
The female part 3 is also multi-divided so that the inner peripheral surfaces of 1 face each other.
1a and 31b are also assembled, and the main body portion 33 (small piece 33
(including a and 33b), the female die 31 and the main body portion 33 are also set on the base 34. 32 in the figure
Is the female mold 3 in order to accurately form a particularly thin part of the thread guide groove.
It is a thin plate piece that is protruded inward from 2 and is inserted into a slightly wide concave groove on the surface of the male die 30.

In the mold thus assembled (see FIG. 3), urea resin is filled (arrow Y) into the cavity having the above-mentioned interval K from the resin supply hole 35 at the top of the main body portion 33, and about 11
After compression molding at 0 ° and cooling, the central extraction rod 36 is first shown in FIG.
, And then the male parts 30a, 3
0b and 30c are pulled out in the centripetal direction of the arrow Z direction (FIG. 4), respectively. Next, the main body portion 33 is opened, and the male portions 31a and 31b inside are removed in the arrow X direction, that is, the centrifugal direction. As a result, a hollow half-cylindrical right half half model 20A as shown in FIG. 5 is obtained. The same operation is performed using another mold having a symmetrical relationship, and the left half half model 20
B is also molded as shown in FIG. Urea resin, which has a low coefficient of thermal expansion, has a contraction rate of 1/10 when cooled from the molding temperature to room temperature.
Since it is about 00, sufficient dimensional accuracy can be obtained.

In the model assembling step B, an appropriate adhesive is applied to the surfaces to be adhered of the pair of left and right half models 20A and 20B and abutted against each other, and set in the bonding jig 40 shown in FIGS. The jig 40 is a holder 4 divided into two having an inner peripheral surface shape capable of closely contacting the outer peripheral surfaces of the semi-models 20A and 20B.
1, 42 are openably and closably connected by a hinge 43, and a screw shaft 44a fixed to one holder 41 is screwed with a nut 44b to be set in a closed state. And
Air between the outer surfaces of the half-models 20A and 20B and the inner surfaces of the holders 41 and 42 is removed from the intake holes 45 as shown by the arrow V to bring the inner surfaces into close contact, and if necessary, into the cavity surrounded by the inner surfaces of the half-models. Compressed air is introduced and the set state is maintained for a sufficiently long time, for example, several times as long as the time required for half-model molding. Therefore, it is desirable to install several bonding jigs for one molding machine and sequentially rotate and use them.

After the bonding is completed, the holders 41 and 42 are opened as shown by an arrow W in FIG. 7, and the model 21 is taken out from the inside. At this time, even a slight dent in the joint portion causes the generation of minute recessed holes in the cast product, and therefore the eye-painting operation with the adhesive is indispensable.

In the mold making process C, the layer 23 of the refractory material 23a is formed as shown in FIG. 9 so as to cover the model 21 and the sprue 22 joined thereto in the peripheral wall. What is normally used in precision casting may be appropriately selected and used. And the refractory material layer 2
After forming No. 3, it is sufficiently dried and then baked at 900 to 1100 ° C. Since the urea resin of the model material melts within about 200 ° C., as shown in FIG. 10, the mold 24 in which the traces of the resin are cavities 24a is obtained all at once in this step.

In the next pouring step D, a pouring device 50 as shown in FIG. 10 is used. In this apparatus, the molten iron 25 of the iron-based alloy is stored in a closed tank 51 except for the intake / exhaust port 52,
On the liquid surface, a tank-shaped mold support 53 provided with an exhaust port 54 is vertically movable. The mold 24 is attached to the mold support 53 in an inverted position with the gate 22 down, the mold 24 is raised to a height such that the lower end thereof is slightly above the liquid surface, and air is exhausted from the intake / exhaust holes 52 as indicated by the arrow R. The internal pressure of 51 is reduced to a level close to vacuum. after that,
As shown by the arrow S, the mold support 53 is gradually lowered, and when the lower end of the mold 24, that is, the lower end of the sprue 22 is slightly submerged in the liquid surface, the inside of the tank 51 is moved in the direction opposite to the arrow R from the intake / exhaust hole 52. When the air is supplied to
Gently ascends in the direction of arrow T to fill the entire cavity 24a. If necessary, the mold 24 may be lowered further slowly following the lowering of the liquid level.

In this way, unlike the conventional gravity type pouring, since the pouring is such that the pouring water is sucked into the cavity 24a of the mold 24 in the inverted position, according to the present embodiment, the local rapid and rapid pouring is performed. There is no risk of non-uniform pouring, and therefore there will be no non-uniform metallographic structure between the respective parts of the traverse drum, which is a cast product.

After the pouring is completed, the mold 24 is taken out of the pouring device 50, the inner and outer refractory material layers 23 are crushed to expose the cast product, and the sprue part is cut, followed by buffing of the surface and rotation unbalance. Adjustment, solution heat treatment, etc.
Further, as described above, a titanium nitride coating or the like is hardened to obtain a finished product.

It should be noted that various modifications can be made such that a melamine resin is used in place of the urea resin in the above-mentioned embodiment, or if the situation permits, a normal pouring is performed instead of the inversion pouring.

[0028]

As described above, according to the present invention,
In particular, it is possible to form a narrow groove by reducing the gradient of the side wall surface of the yarn guide groove that is opposite, and not only to significantly reduce the groove width, but also to save the cost for pollution control because soluble wax is not used. it can. Further, the autoclave in the dewaxing step, which was indispensable in the past, is no longer necessary, and it is not necessary to spend a long time for the wax removal, so that the work step time can be shortened. Further, since it is possible to provide a lightweight drum having a wall thickness significantly smaller than that of the conventional product, it becomes easy to increase the number of rotations of the drum, and the power cost for driving the rotation can be reduced.

[Brief description of drawings]

FIG. 1 is a longitudinal sectional view of a traverse drum manufactured by the method of the present invention.

FIG. 2 is a process drawing of an example according to the method of the present invention.

FIG. 3 is a vertical cross-sectional view of a mold for molding a half model.

FIG. 4 is a plan view showing an operation of opening the mold.

FIG. 5 is a perspective view of the right half model after molding.

FIG. 6 is a perspective view of the left half model.

FIG. 7 is a plan view of an adhesive jig for model assembly.

FIG. 8 is a front view of the same.

FIG. 9 is a cross-sectional view showing a state in which the refractory material layer is formed on the inner and outer surfaces of the model in the mold manufacturing process.

FIG. 10 is a vertical sectional view of a pouring device used in a pouring process.

FIG. 11 is a longitudinal sectional view of a traverse drum manufactured by a conventional method.

[Explanation of symbols]

 1 Traverse drum 20A Half model 20B Half model 21 Model 22 Gate 22 Refractory material layer 23a Refractory material 24 Mold 25 Molten metal 50 Pouring machine

Claims (3)

[Claims] 1. A casting method in which a model is made of a soluble material, the model is removed by immersing the model in a mold material, and then the model is made hollow, and molten metal is poured into the cavity to obtain a product. Synthetic resin is used as above, and two thin hollow semi-models, which are divided into two in the axial direction of the traverse drum, are molded in a mold, and these two semi-models are joined with an adhesive to obtain the above model. , Repeating the operation of dipping the model in the refractory slurry of the mold material and pulling and drying, the refractory layer adhered and formed on both inner and outer surfaces of the model reaches a required thickness, and then the refractory layer is removed. When firing, a hollow mold is produced by melting and removing the model sandwiched between the refractory layers at the same time, and then precision casting operations such as pouring and post-treatment are performed. Traverse drum manufacturing method . 2. Each of the half-models made of the synthetic resin is molded by a mold having a multi-divided structure, and the joining operation is divided into two parts having an inner peripheral surface closely contacting the outer peripheral surface of the half-model. The method of manufacturing a traverse drum according to claim 1, wherein the method is performed in an opening / closing adhesive jig. 3. The method for manufacturing a traverse drum according to claim 1, wherein a urea resin is used as the synthetic resin.