JPH11132250A - Method and device for manufacturing urethane coupling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and a device for manufacturing a urethane coupling, capable of filling urethane in a space between a pair of circular hubs while removing bubbles existing in liquid urethane. SOLUTION: A manufacturing method is provided with a first process for positioning a pair of circular hubs provided with a plurality of protrusions on the end surfaces and center holes so that the protrusions may be in the meshed state with spaces, a second process for filling liquid urethane into the spaces by allowing it to flow by centrifugal force, and a third process for joining a pair of circular hubs by interposing urethane elastomer through a process of reacting and solidifying liquid urethane while keeping centrifugal force. A shaft 11 is used for the axial and circumferential positioning of a pair of circular hubs 2, 3, and a device is used, for rotating upper and lower metal molds 12, 13 capable of being heated, opened and closed in the horizontal surface, in which housing parts 18, 25 for fixing the shaft 11 and covering the hubs 2, 3 are arranged in many lines at a equal distance concentrically with the rotational center.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for manufacturing a urethane coupling in which a pair of circular hubs having a plurality of projections on an end face and a center hole are joined via a urethane elastomer.

[0002]

2. Description of the Related Art An elastic shaft coupling connects a drive shaft and a driven shaft via an elastic body, and transmits power while absorbing eccentricity and declination between the two shafts by deformation of the elastic body. It is.
As an elastic body of such a conventional elastic body joint which uses rubber, there is one defined in a rubber joint of JIS-B1455.

[0003] In this rubber joint, a pair of projections provided with a plurality of projections at equal intervals in the circumferential direction are opposed to end faces of a pair of circular hubs having a center hole to be fitted into a shaft, and the projections are alternately arranged. And a rubber elastic body is interposed as a damper in a space formed between the circular shape and the projection.

In transmitting power from the drive shaft to the driven shaft, the protrusion of the circular hub on the drive shaft presses the rubber elastic body, and the rubber elastic body receives the pressing force, and the protrusion of the circular hub on the driven shaft side receives the pressing force. Pressing is performed. At this time, even if there is an eccentricity and an eccentric angle between both shafts, the eccentricity and the eccentric angle are absorbed by the elasticity of the rubber elastic body. A urethane coupling using a urethane elastomer is known as a material for sufficiently exerting the function of such a rubber elastic body.

[0005] This urethane elastomer is of the type that thermally cures liquid urethane. The pair of circular hubs are engaged with each other with a space having protrusions, and the space is filled with liquid urethane, and is heated and cured. Conventionally, this filling operation holds a pair of circular hubs in a mold,
This has been done by injecting liquid urethane into the space.

[0006]

However, since the conventional urethane casting is performed under atmospheric pressure, there is a problem that bubbles existing in the liquid urethane cannot be removed and remain. If bubbles remain, a predetermined rebound resilience cannot be obtained. These bubbles are generated when the liquid urethane is weighed and stirred, and avoiding bubbles during the weighing and stirring steps complicates the manufacturing process.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method and an apparatus for manufacturing a urethane coupling capable of filling a space between a pair of circular hubs while removing bubbles existing in liquid urethane. It is in.

[0008]

According to a first aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: a pair of circular hubs each having a plurality of projections on an end face and a center hole; A first step of positioning the liquid urethane into the space by centrifugal force to fill the space with the liquid urethane; and, while maintaining the centrifugal force, reacting and curing the liquid urethane to form the pair of hubs with urethane. And a third step of joining with an elastomer interposed therebetween. The centrifugal force can be generated by rotation, and the rotation is performed in a horizontal plane or a vertical plane.

In the first aspect, the positioning in the first step is performed by penetrating a shaft through the center holes of the pair of hubs and fixing each hub at a predetermined position in the axial direction and the circumferential direction of the shaft. The protrusions of the hub face each other with a space so as to be engaged with each other, and further, the pair of hubs are fixed in the openable and closable upper and lower dies via the shaft, The centrifugal force in the two steps is generated by rotating the upper and lower molds in a horizontal plane or a vertical plane, and the reaction hardening in the third step is performed by injecting liquid urethane, The fourth step is a step of removing the pair of hubs together with the shafts from the upper and lower molds, and then removing the shaft as a fourth step. Obtaining (Claim 2). In claim 2, the fixing of the pair of hubs at a predetermined position in the axial direction of the shaft is performed by bringing an end face of each hub into contact with a step between a large diameter portion and a small diameter portion of the shaft. The fixing of the pair of hubs at a predetermined position in the circumferential direction of the shaft is performed using a screw hole opened in the through hole of each hub with respect to a plane portion provided at a predetermined position of the shaft. It is performed by screwing (claim 3). 3. The fixing method according to claim 2, wherein the fixing of the pair of hubs through the shaft in the upper and lower molds includes an upper protruding portion and a lower protruding portion that protrude from respective center holes of the pair of hubs.
This is performed by fitting the lower protruding portion to the lower mold and fitting the upper protruding portion to the upper mold. Claim 2
In the upper and lower molds, a large number of storage portions of the hub and fixing portions of the shaft are arranged in a row on a concentric circle with respect to a center of rotation. Claim 2
In the above, the upper and lower molds are configured such that a housing portion of the hub and a fixing portion of the shaft are arranged concentrically with respect to a rotation center, and the liquid urethane is injected around the housing portion. And a reservoir for causing the same shrinkage of urethane in the gate as described above, and the reservoir is disposed at least at a position facing the gate (claim 6).

According to a seventh aspect of the present invention, there is provided an apparatus according to the seventh aspect, wherein a pair of circular hubs having a plurality of projections on an end face and a center hole are provided so that the projections have a space and engage with each other. A shaft penetrating through the hole and fixedly positioning the hubs at predetermined positions in the axial and circumferential directions of the shaft; and a storage portion for fixing the shaft and covering the hub, being equally divided on a concentric circle around the center of rotation. A plurality of heatable and openable upper and lower molds arranged in a row, a driving means for supporting at least one of the upper and lower molds and rotating the upper and lower molds around the rotation center, and the other of the upper and lower molds Opening at the center of rotation of the, the injection port for injecting liquid urethane, and a gate portion that radially communicates from the injection port toward the plurality of storage sections and guides the liquid urethane to each storage section, Prepare This is a manufacturing apparatus for a urethane coupling. It is preferable that the rotation center is disposed vertically, and the upper and lower molds are rotated in a horizontal plane. However, when pouring liquid urethane, the center of rotation may be vertical, and when rotating the upper and lower dies, the center of rotation may be horizontal and rotated in a vertical plane. In claim 7, an elastic ring is used for a fitting portion between the shaft and the hub and a fitting portion between the hub and the upper and lower molds (claim 8). In claim 7, the liquid urethane reservoir is disposed at least at a position around the storage portion and facing the gate portion (claim 9).

As the polyurethane elastomer,
Dicisocyanates represented by toluene dicisocyanate (TDI), methylene diisocyanate (MDI), paraphenylene diisocyanate (PPDI) and the like;
A polyurethane elastomer obtained by blending a curing agent (crosslinking agent) with a prepolymer of one or more of polyester-based polyols, polyether-based polyols, and polycarbonate-based polyols is used.

The polyester polyol is, for example, a condensate of a polycarboxylic acid and a low molecular weight polyol,
Those having a molecular weight of 500 to 10,000 are mentioned. Examples of the polyether-based diol include, for example, an alkylene oxide (eg, ethylene oxide, propylene oxide) and a polyhydric alcohol that is an active hydrogen compound (eg,
Those obtained by ring-opening addition polymerization using (ethylene glycol) as an initiator are exemplified. Examples of the polycarbonate polyol include those obtained by condensation of a conventionally known polyol (polyhydric alcohol) with phosgene, chloroformate, dialkyl carbonate or diallyl carbonate, and having various molecular weights.

One or more of the above polyols are
The method for producing a urethane prepolymer (liquid urethane) by reacting with a diisocyanate represented by DI, MDI and PPDI is not particularly limited.
For example, the reaction can be performed by a known method, including the reaction temperature, reaction time, the presence or absence of a solvent, and the like. In order to obtain the urethane elastomer used in the present invention, the urethane prepolymer obtained as described above may be mixed with a curing agent to cure the urethane prepolymer (reaction curing).

The curing agent that can be used is not particularly limited, and may be any of those generally used when a urethane prepolymer is cured to form a urethane elastomer. For example, a polyol compound, a polyamine compound and the like can be mentioned. The polyol compound is not particularly limited, and any of a primary polyol, a secondary polyol, and a tertiary polyol may be used.

The method for curing (crosslinking) the urethane prepolymer by mixing the above-described curing agent with the urethane prepolymer obtained as described above is not particularly limited. It can be carried out by a usual method, including the mixing ratio of the curing agent to the prepolymer, the curing temperature, the curing time, and the like. The polyurethane elastomer used in the present invention may contain additives and the like. This additive is a plasticizer, a flame retardant, a filler, a stabilizer, a colorant, or the like. Stabilizers include conventionally used antioxidants, ultraviolet absorbers, light stabilizers, hydrolysis inhibitors and the like.

In the present invention, the liquid urethane is reacted and cured while maintaining the centrifugal force. Therefore, in order to promote the reaction, the upper and lower molds can be heated. The liquid urethane from which the bubbles have been displaced by the centrifugal force fills the space between the pair of circular hubs, and promotes reaction curing while maintaining the state. Positioning of the pair of circular hubs with respect to the upper and lower molds is performed via a shaft. Liquid urethane filling the space between the pair of circular hubs is injected through the gate of the mold. If a reservoir of liquid urethane communicating with the space is provided at least at a position facing the gate in order to oppose the contraction of urethane in the gate, the contraction of the urethane around the shaft becomes point symmetric. When the shaft is removed and made into a urethane coupling, the contraction of urethane around the shaft is symmetrical around the shaft, so that eccentricity and declination of the center holes of the pair of hubs are prevented, and a highly accurate urethane cup is provided. A ring is obtained.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of a manufacturing apparatus used in the method of the present invention, FIG. 2 is a top view of a lower mold in the manufacturing apparatus, and FIG. 3 shows a mounting state of a shaft and a hub in the manufacturing apparatus. FIG. 4 is a cross-sectional view, and FIG. 4 is a vertical cross-sectional view showing a mounting state of the shaft and the hub.

First, the entire apparatus of the present invention will be described with reference to FIGS. The apparatus of the present invention includes a shaft 11 for fixing a pair of circular hubs 2 and 3 at a predetermined position, a lower mold 12 and an upper mold 13 capable of fixing a large number of the shafts 11, and a lower mold 12.
Plate (driving means) 14 for supporting the
And a drive motor (drive means) 15 for rotating the motor at high speed.

The drive motor 15 has a vertically upward output shaft 15.
a is attached to the center of rotation of the horizontally arranged rotating plate 14 by fitting or the like. A circular lower mold 12 is fixed on the rotating plate 14 with bolts 16 so that the centers thereof are aligned.

The lower circular mold 12 has a lower two-stage hole 19 including a lower fixing portion 17 corresponding to the lower projecting portion 41 of the shaft 11 and a lower housing portion 18 corresponding to one of the circular hubs 2 and 3.
Are equally arranged on the concentric circle 21 of the rotation center 20 as shown in FIG. 2 (12 equally arranged in the illustrated example). A lower circular storage part 22 is provided around the rotation center 20, and a lower gate part 23 extending radially from the lower circular storage part 22 to each lower storage part 18 is provided.

Returning to FIG. 1, the circular upper mold 13 also includes an upper fixing portion 24 corresponding to the upper protrusion 42 of the shaft 11 and an upper storage portion 25 corresponding to the other of the circular hubs 2 and 3. The two-stage hole portion 26 is disposed so that the axis thereof coincides with the lower two-stage hole portion 19 of the lower mold 12. In addition, an upper circular storage portion 27 and an upper gate portion 28 corresponding to the lower circular storage portion 22 and the lower gate portion 23 of the lower die 12 are also provided in the upper die 13. The upper and lower circular storage portions 22 and 27 and the upper and lower gate portions 23 and 28 are integrated as a circular storage portion and a gate portion.
It can also be provided on only one of the upper and lower molds 12, 13.

Along the rotation center 20 of the upper mold 13,
An inlet 29 extending to the upper and lower circular storage portions 22 and 27 is provided. The upper and lower dies 12, 13 are fixed in a closed state by bolts 13a. The bolts 13a allow the upper and lower dies 12, 13 to be freely opened and closed. The upper and lower dies 12 and 13 have built-in heating means such as an electric heater (not shown). Further, O-rings (elastic body rings) 30, which seal between the second housing portion 18 of the lower mold 12 and the second housing portion 25 of the upper mold 13 near the outer periphery of the circular hub, are provided near the mating surfaces. 31 are provided.

Starting from the gates 23 and 28 of the upper and lower molds with the shaft 11 as a center, the first reservoir 32 divided into upper and lower molds is located at a parallel position + 180 ° apart.
U, 32L are disposed, and the second reservoirs 33U, 3 are divided into upper and lower dies at orthogonal positions separated by + 90 °.
3L, and third reservoirs 34U and 34L, which are divided into upper and lower dies, are disposed at orthogonal positions separated by -90 °. Gate portions 23 and 28, first storage portion 32
The U, 32L, the second reservoirs 33U, 33L and the third reservoirs 34U, 34L are provided so as to communicate with the space between the pair of circular hubs 2, 3 in the upper and lower mold storage portions 18, 25. Have been.

The first reservoirs 32U and 32L are connected to the gate 2
It has the same length and the same width as 3,28. With the gate portions 23 and 28, the amount of urethane increases and the amount of shrinkage increases accordingly. The contraction of the urethane in the first reservoirs 32U, 32L can directly oppose the contraction of the urethane in the gates 23, 28. First reservoir 32
In the absence of U, 32L, shaft 11 is opposing this contraction. For this reason, when the shaft 11 is removed, the urethane on the side where the gate portions 23 and 28 are located is greatly contracted, which causes eccentricity and declination of the pair of circular hubs. Therefore,
In order to resist the contraction of the urethane of the gate portions 23, 28, at least +180 from the gate portions 23, 28
The first reservoirs 32U and 32L are provided at opposed positions separated by °. When the same phenomenon as the urethane contraction in the gate portions 23 and 28 is generated so as to be symmetrical around the shaft 11, the contraction around the shaft 11 becomes substantially uniform. Therefore, it is preferable to provide the second reservoirs 33U and 33L and the third reservoirs 34U and 34L with the same length and the same width as the gates 23 and 28. As shown,
The gate 2 is located at a position where the circumference of the storage sections 18 and 25 is equally divided into four.
3, 28, first reservoirs 32U, 32L, second reservoir 33
When the U, 33L and the third reservoirs 34U, 34L are provided,
The contraction of the urethane in the space inside the storage sections 18 and 25 is balanced more symmetrically with respect to the shaft 11. As a result, when the shaft 11 is pulled out to form a urethane coupling, the eccentricity and declination of the center holes of the pair of circular hubs caused by the uneven distribution of urethane are suppressed.

Referring to FIGS. 3 and 4, a description will be given of an attachment body between the circular hubs 2 and 3 and the shaft 11. FIG. FIG. 4 is a sectional view taken along line XX of FIG.
It is a line sectional view. In FIG. 3, a large-diameter first protrusion 41 is provided.
The first shaft portion 43 and the second shaft portion 44, each having a smaller diameter, are provided from the first to the second protrusion 42 having a smaller diameter. Between the large diameter first projection 41 and the small diameter first shaft 43, the first
A step portion 45 is formed, and the large-diameter first shaft portion 43 and the small-diameter second shaft portion 43 are formed.
A second step 46 is formed between the second step 46 and the shaft 44. Further, near the end face of the first shaft portion 43 on the side facing the circular hub 2,
O-rings (elastic rings) 47 and 48 for sealing between the center holes of the circular hubs 2 and 3 are arranged near the end face of the second shaft portion 44 on the side facing the circular hub 3. Further, flat portions 49 and 50 facing the bolt holes of the circular hubs 2 and 3 are provided at an intermediate position of the circular hub 2 of the first shaft portion 43 and an intermediate position of the circular hub 3 of the second shaft portion 44. I have.

The structure of the circular hubs 2 and 3 will be described with reference to FIGS. FIG. 6 is a sectional view taken along line YY of FIG. In FIG. 5, a pair of circular hubs 2 and 3 made of an aluminum alloy
They have center holes 4 and 5, respectively, and have projections 6 and 7 projecting from end faces facing each other. As shown in FIG. 6, the three projections 6, 6, 6 of the circular hub 2 and the three projections 7, 7, 7 of the circular hub 3 are arranged in a meshing state via a space separated by the same distance from each other. I have. The urethane elastomer 8 in this space has a structure in which the pair of circular hubs 2 and 3 are joined. Normally, the center hole 4 of one circular hub 2 is larger in diameter than the center hole 5 of the other circular hub 3. The inside of the urethane elastomer 8 is a ring having the same inner diameter as the center hole 4, and a portion extending radially from the ring fills a space between the projections 6 and 7. Further, a bolt hole 9 opening to the center hole 4 is provided at an intermediate position of the main body of the circular hub 2, and a bolt hole 10 opening to the center hole 5 is also provided at an intermediate position of the main body of the circular hub 3. When aluminum alloy is used for the circular hubs 2 and 3,
In order to improve the adhesion with the urethane relastomer 8, it is desirable to apply a treatment for improving the adhesion in which an adhesive is applied in advance to opposing portions of the circular hubs 2 and 3.

Returning to FIG. 3, the first shaft portion 43 of the shaft 11
Has an outer diameter that fits into the center hole 4 of the circular hub 2, and the end of the circular hub 2 on the side opposite to the opposing surface hits the first step portion 45, thereby determining the axial position with respect to the shaft 11. Also, the second shaft portion 44 of the shaft 11 has an outer diameter that fits into the center hole 5 of the circular hub 3, and the end of the circular hub 3 on the facing surface side contacts the second step portion 46, and the shaft with respect to the shaft 11. The direction position is determined. As a result, the distance ε between the protrusion 6 of the circular hub 2 and the circular hub 3 and the protrusion 7 of the circular hub 3 and the circular hub 2
Is automatically determined.

When the set screw 51 is screwed into the bolt hole 9 of the circular hub 2, the tip of the set screw 51 is perpendicular to the flat portion 49, and the circumferential position of the shaft 11 of the circular hub 2 is determined. Similarly, a set screw 52 is inserted into the bolt hole 10 of the circular hub 3.
When the screw is screwed in, the tip of the set screw 52 is perpendicular to the flat portion 50, and the circumferential position of the shaft 11 of the circular hub 3 is determined. As a result, as shown in FIG.
The gap 53 between the circular hub 3 and the projection 7 of the circular hub 3 has the same angle α, so that the circumferential positions of the circular hubs 2 and 3 are automatically determined.

As described above, the circular hub 2,
3 in sequence, hit against the steps 45, 46, and set screws 51,
By simply screwing in 52, the axial position and the circumferential position of the circular hubs 2, 3 with respect to the shaft 11 are determined. A predetermined space 5 having protrusions 6 and 7 interposed between the circular hubs 2 and 3
4 are formed.

Next, the production method of the present invention using the above-described apparatus of the present invention will be described. As shown in FIG.
A circular hub 2 having a large center hole 4 is fitted into 1, and an end face of the circular hub 2 is brought into contact with a first step portion 45. Next, the circular hub 3 having the small center hole 5 is fitted into the shaft 11,
The end face of the circular hub 3 is brought into contact with the second step 46. Then, the stop bolt 51 is screwed into the screw hole 9 of the circular hub 2, and the front end of the stop bolt 51 is brought into contact with the flat portion 49. Similarly, a stop bolt 52 is screwed into the screw hole 10 of the circular hub 3, and the front end of the stop bolt 52 is applied to the flat portion 50. In this manner, the axial position and the circumferential position of the pair of circular hubs 2 and 3 with respect to the shaft 11 are determined, and the space 54 such as the axial gap ε and the gap 53 between the protrusions 6 and 7 has a predetermined shape ( First step).

The bolt 13a shown in FIG. 1 is removed, and the upper mold 13 is removed. The shaft 11 and the circular hub 2 shown in FIG.
The mounting body of No. 3 is set at a predetermined position of the lower mold 12 by fitting the lower protruding portion 41 into the lower fixing portion 17. Next, the upper mold 13 is lowered along the rotation center 20, and the upper protrusion 42 is fitted into the upper fixing part 24, thereby forming the upper mold 13.
The bolt 13a is screwed in while ensuring concentricity with the lower mold 12. Then, the shaft 11 of FIG.
12 are set in the upper and lower molds 12, 13, and the space between the circular hubs 2, 3 is defined by the gates 23, 2.
8. A state of communication with the inlet 29 through the circular storage portions 27 and 28 is established. When the drive motor 15 is rotated in this state, the upper and lower dies 12 and 13 are rotated via the rotating disk 14, and a large centrifugal force is generated in the attachment of the shaft 11 and the circular hubs 2 and 3. Injection port 2 with centrifugal force generated
When the liquid urethane is injected from the container 9, the circular storage portions 27, 2
8. The space between the circular hubs 2 and 3 is filled with liquid urethane via the gate portions 22 and 27 (second step).

While the centrifugal force is generated, the upper and lower dies 12, 1
When 3 is heated, the reaction curing of the liquid urethane proceeds. Since the centrifugal force is still generated, even if bubbles are present in the liquid urethane, the bubbles having a low specific gravity are removed from the circular storage section 2.
The liquid urethane in the space between the circular hubs 2 and 3 which gathers at 7, 28 has the highest centrifugal force and almost no bubbles are present. When the liquid urethane in the space of the circular hubs 2 and 3 reacts and hardens and changes to urethane elastomer, the circular hubs 2 and 3
3 are joined with a urethane elastomer (third step).
At this time, the urethane in the space of the circular hubs 2 and 3 is pulled by the contraction of the urethane in the gate portions 23 and 28, but the tension from the first storage portions 32U and 32L is opposed, and the second storage portions 33U and 33L. And the third reservoir 34
The U and 34L regulate the movement of urethane in the space between the circular hubs 2 and 3, and the shrinkage of the urethane is made uniform in the circumferential direction.
Therefore, when the shaft 11 is pulled out, eccentricity and declination of the center holes of the pair of circular hubs caused by the contraction of the urethane do not occur.

The rotation of the upper and lower dies 12, 13 is stopped, the bolt 13a is removed, and the upper and lower dies 13 and 12 are opened. Then, the twelve attachment bodies of the shaft 11 and the circular hubs 2 and 3 are removed from the lower mold 12. And set screw 51,5
2 is loosened and removed, and the shaft 11 is removed from the mounting body.
The gate portion of the urethane elastomer filled in the space between the circular hubs 2 and 3 is cut to obtain a urethane coupling having a predetermined shape (fourth step).

In the second and third steps of applying the centrifugal force, excess leakage of the liquid urethane into the storage portion 25 is stopped by the elastic rings 30 and 31, and the liquid urethane is similarly transferred to the central holes 4 and 5 of the liquid urethane. The extra leak is caused by the elastic ring 47 in FIG.
Stopped at 48. For this reason, finishing work is simplified until a urethane coupling having a predetermined shape is obtained. However, the elastic rings 47 and 48 are not always necessary. This is because it may be preferable to omit the elastic rings 47 and 48 in order to increase the accuracy of the shaft runout.

As described above, twelve urethane couplings can be obtained in one step of applying centrifugal force. Further, since the pair of circular hubs 2 and 3 are configured to be positioned by the shaft 11, even if a large centrifugal force acts.
The positional relationship between the pair of circular hubs 2 and 3 does not shift,
A highly accurate urethane coupling can be obtained.

[0036]

EXAMPLE An upper and lower mold having a concentric circle diameter (PCB) of 205 mm and capable of setting 12 mounting bodies of a shaft and a circular hub was used. As a prepolymer (liquid urethane), polyester T.V. D. I. A-9, which is a polyol-based crosslinking agent, is used as a crosslinking agent for Vibrathane 8050 (manufactured by Uniroyal), which is a urethane prepolymer.
31 (manufactured by Uniroyal Co.) and MOCA (manufactured by Wakayama Seika) as an amine-based cross-linking agent were mixed as shown in Table 1 and used by stirring in advance.

[0037]

[Table 1]

The upper and lower dies in a horizontal arrangement are placed around the center axis by 400
Rotate at 0 rpm ± 500 rpm for a predetermined time of 30 to 4
Leave centrifugal force applied for 0 minutes, and simultaneously
The liquid urethane was cured by heating at 0 to 130 ° C. After curing, the shaft was removed from the upper and lower molds, and the circular hub joined with the urethane elastomer was removed from the shaft to obtain a urethane coupling. Bubbles are not visible in the urethane elastomer after crosslinking at this time,
The rebound resilience of urethane elastomer is 30% (JISK
6301). The centrifugal force at 3500 rpm is 1404G, and the centrifugal force at 4500 rpm is 2321G. Therefore, the centrifugal force required for urethane injection is 1350-2400G.

Next, when the reservoirs are arranged at positions where the urethane of the upper and lower mold gates can resist urethane contraction, how much eccentricity and declination of the center holes of the pair of circular hubs can be prevented is measured. did.

As shown in FIG. 2, both a mold having a gate portion and three reservoir portions equally arranged on the circumference and a mold having no gate portion and having only the gate portion are used. Diameter 30mm,
96 urethane couplings having shaft diameters of 8 mm at both ends were obtained with three reservoirs and 59 without the reservoirs. The shaft of one hub is inserted into the rotating shaft, and 1 m inside the shaft of the other hub.
The runout of m was measured with a test indicator, and the results are shown in Table 2. In Table 2, the average is the average of 96 or 59 measurements, MAX is the maximum of the 96 or 59 measurements, and MIN is 96 or 59
Is the smallest of the measurements. It can be seen that when the shrinkage of urethane in the mold is made uniform in the circumferential direction, the eccentricity and declination of the resulting urethane coupling are greatly improved.

[0041]

[Table 2]

[0042]

According to the manufacturing methods of the present invention, the following effects can be obtained. The liquid urethane is injected into the space between the pair of circular hubs by centrifugal force, and the liquid urethane is reacted and hardened while maintaining the centrifugal force. The pair of hubs can be joined via a predetermined urethane elastomer (claim 1). Since a pair of circular hubs are positioned using a shaft, the positional relationship between the circular hub protrusions and the concentricity of the circular hub can be maintained with high precision, and only the shaft and the circular hub that have been set in advance need be attached to the mold. Therefore, the work process can be streamlined (claim 2). The step in the axial direction of the shaft determines the axial position of the pair of circular hubs, and the screwing to the shaft determines the circumferential position of the pair of circular hubs. (Claim 2). Further, the upper and lower projecting portions of the shaft make it possible to easily set the mounting body of the shaft and the circular hub on the upper and lower molds while maintaining the accuracy of the pair of circular hubs with respect to the shaft (claim 4). A large number of urethane couplings can be manufactured in a short time because a mold is used in which a large number of storage portions of the shaft and the mounting body of the circular hub are equally arranged on a concentric circle. Around the accommodating portion, a gate portion for injecting the liquid urethane and a reservoir portion for causing the same contraction of urethane in the gate portion are provided, and the reservoir portion faces at least the gate. In this case, a highly accurate urethane coupling can be manufactured (claim 6).

According to the apparatus of the present invention, the following effects can be obtained. A large number of urethane couplings having no bubbles in the urethane can be manufactured at a time (claim 7). With the use of elastic rings at key points,
The liquid urethane does not go to unnecessary places, and the finishing in the subsequent process and the cleaning of the mold are simplified (claim 8). When the liquid urethane reservoir is disposed at least at a position around the storage section and facing the gate section, eccentricity and declination of the center holes of the pair of circular hubs can be prevented. 9).

[Brief description of the drawings]

FIG. 1 is a sectional view of a manufacturing apparatus used in the method of the present invention.

FIG. 2 is a top view of a lower mold in the manufacturing apparatus.

FIG. 3 is a cross-sectional view showing a mounting state of a shaft and a hub in the manufacturing apparatus.

FIG. 4 is a longitudinal sectional view showing a mounting state of the shaft and the hub.

FIG. 5 is a cross-sectional view of a urethane coupling according to the present manufacturing method.

FIG. 6 is a longitudinal sectional view of a urethane coupling according to the present manufacturing method.

[Explanation of symbols]

 2 Circular hub 3 Circular hub 4 Center hole 5 Center hole 6 Projection 7 Projection 8 Urethane elastomer 9 Screw hole 10 Screw hole 11 Shaft 12 Lower mold 13 Upper mold 14 Rotary plate 15 Drive motor (drive means) 17 Lower fixing part 18 Lower storage part 20 Rotation center 23, 28 Gate part 24 Upper fixed part 25 Upper storage part 29 Inlet 30 Elastic ring 31 Elastic ring 32U, 32L First storage part 33U, 33L Second storage part 34U, 34L Third storage part 41 Lower projecting part 42 Upper projecting part 43 First shaft part 44 Second shaft part 45 First step part 46 Second step part

Claims (9)

[Claims] 1. A first step of positioning a pair of circular hubs having a plurality of protrusions on an end face and a center hole so that the protrusions have a space and mesh with each other; A urethane coupling comprising: a second step of inflowing and filling with a centrifugal force; and a third step of reacting and curing the liquid urethane while maintaining the centrifugal force, and joining the pair of hubs through a urethane elastomer. Manufacturing method. 2. The positioning in the first step is performed by passing a shaft through the center holes of the pair of hubs, and fixing each hub at a predetermined position in the axial direction and the circumferential direction of the shaft. The projections are faced so as to be engaged with each other with a space, and the pair of hubs are fixed in the openable and closable upper and lower molds via the shaft. The centrifugal force is generated by rotating the upper and lower molds, and the reaction hardening in the third step is performed while the upper and lower molds are rotating after injecting liquid urethane. The urethane coupling according to claim 1, further comprising, as a fourth step, a step of removing the shaft after removing the pair of hubs together with the shaft from the upper and lower molds. Manufacturing method. 3. The fixing of the pair of hubs at a predetermined position in the axial direction of the shaft is performed by bringing an end face of each of the hubs into contact with a step between a large diameter portion and a small diameter portion of the shaft. The fixing of the pair of hubs at a predetermined position in the circumferential direction of the shaft is performed using a screw hole opened in the through hole of each hub with respect to a plane portion provided at a predetermined position of the shaft. 3. The method for producing a urethane coupling according to claim 2, wherein the method is performed by screwing. 4. The fixing of the pair of hubs in the upper and lower molds via the shaft is provided with an upper protruding portion and a lower protruding portion protruding from respective center holes of the pair of hubs.
The method for manufacturing a urethane coupling according to claim 2, wherein the lower protrusion is fitted to the lower mold, and the upper protrusion is fitted to the upper mold. 5. The urethane cup according to claim 2, wherein the upper and lower molds are formed by arranging a large number of storage portions for the hub and fixing portions for the shaft on the concentric circle with respect to the center of rotation. Ring manufacturing method. 6. The upper and lower molds are configured such that a housing portion of the hub and a fixing portion of the shaft are arranged concentrically with respect to a rotation center, and the liquid urethane is provided around the housing portion. 3. The gate according to claim 2, further comprising a gate portion for injection, and a reservoir portion for causing a contraction similar to the contraction of urethane in the gate portion, wherein the reservoir portion is disposed at least at a position facing the gate. A method for producing a urethane coupling. 7. A pair of circular hubs having a plurality of protrusions on an end face and a center hole are penetrated through the center hole such that the protrusions have a space and mesh with each other. A shaft fixedly positioned at a predetermined position in the axial direction and the circumferential direction, and a plurality of storage sections that fix the shaft and cover the hub in a concentric circle around the center of rotation, are arranged in equal rows and are heatable and openable. Upper and lower molds, driving means for supporting at least one of the upper and lower molds and rotating the upper and lower molds around the rotation center, and opening at the other rotation center of the upper and lower molds, a liquid urethane. An inlet for injecting, and a gate portion that radially communicates from the inlet to the plurality of storage portions and guides the liquid urethane to each storage portion,
An apparatus for producing a urethane coupling comprising: 8. A fitting portion between the shaft and the hub,
The urethane coupling manufacturing apparatus according to claim 7, wherein an elastic ring is used for a fitting portion between the hub and the upper and lower molds. 9. The urethane coupling manufacturing apparatus according to claim 7, wherein a reservoir for the liquid urethane is disposed at least at a position around the storage section and facing the gate section.