JPS5927696B2 - Manufacturing equipment for synthetic resin cages for radial rolling bearings - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a rolling element retainer made of synthetic resin with a D-bearing, in which radial rolling is carried out axially by a large number of axial columns uniformly distributed along the circumference. A manufacturing device for a cage, which is constructed by connecting two annular collars at both ends of the cage, and includes a cylindrical core having an outer diameter equal to the inner diameter of the cage, and a radially movable collar. This type of mold consists of a mold having an outer mold part and surrounding a core.

Injection molding devices of this type have already been used for some time for producing cages made of synthetic resin with so-called rolling element receiving pockets.

However, in such conventionally known injection molding equipment, the manufacturing cost of the cage is quite high because the equipment itself is expensive and only one cage is manufactured in each injection molding process. It had the disadvantage of becoming a thing. Therefore, when mass-producing cages, it is necessary to attach a specific mold to one injection molding machine and use it exclusively for a very long time, which reduces the efficiency of injection molding machine utilization. It is extremely uneconomical.

SUMMARY OF THE INVENTION Therefore, the object of the present invention is to easily and inexpensively eliminate these drawbacks, significantly reduce the manufacturing cost of a synthetic resin retainer for a radial rolling bearing, and enable economical use of injection molding equipment. It is to be.

In order to achieve this object, the present invention has a structure in which at least two cages are molded coaxially and at a distance from each other at the same time in an apparatus for manufacturing synthetic resin cages for radial rolling bearings of the type described above. at least two cavities are formed in the radially inner end faces of said movable outer mold part, forming said mutually opposite end faces of adjacent spaced apart flanges of said at least two cages; A surface is provided on said radially movable outer mold part, each cavity having a respective gate, which gates are connected between the cavities with a sprue coaxial with the core. They opened into a common runner, and the core had a dividing plane perpendicular to the axis of the sprue between the cavities.

Of course, it is known to injection mold many identical products at the same time in one mold, but all of these products have simple shapes and use one mold with a cylindrical core. Conventionally, it has not been possible to simultaneously injection mold two or more retainers for radial rolling bearings.

This is because the structure of the mold becomes extremely complicated and it becomes extremely difficult to demold the product.
The configuration and effects of the present invention will be specifically explained below with reference to the drawings.

In the illustrated embodiment, numerals 1 and 2 respectively designate cylindrical core parts, and the mold 4 is further configured to guide a number of movable outer mold parts 3 in the radial direction.

As can be seen in particular from FIG. 1, according to the invention, a cavity 5 is formed in such a way that at least two cages, in one case two cages, are molded coaxially and spaced apart from each other simultaneously.
and 6 are formed on the radially inner end surface of the movable outer mold part, and these two cavities 5 and 6 are closed from the outside in the radial direction by the movable outer mold part 3VC. . In this case, projections 7 and 8 are left on the end face of the movable outer mold part 3 in order to form a pocket for accommodating the rolling elements of the cage (a space partitioned by a collar and a pillar). In the axial direction of cavities 5 and 6,
The ends at the mutually opposite end faces 9 and 10 of the spacingally adjacent collars 11, 12 of the two cages are again closed by the movable outer mold part 3. In other words, the molding surfaces of the end faces 9 and 10 are provided with the movable outer mold portion 3VC. The other axial end of the cavity 5 is closed by a product sector 13 , and the other axial end of the cavity 6 is shaped by the core part 2 . Each cavity 5, 6 is provided with a gate 14 or 15 respectively, both gates 14, 15 being connected to the core part 1 via a common runner 16 located intermediate both cavities 5, 6. and a sprue 17 formed along the two axes.

The gates 14 and 15 have narrow connection holes to the cavities 5 and 6, and the gates 14 and 15 have narrow connection holes to the cavities 5 and 6.
Excess synthetic resin (flash) that has hardened in the product holder 5 can be easily peeled off from the collars 11, 12 of the product holder at these connection holes. Make sure to hold the hardened surplus synthetic resin in the sprue 1r, and
In order to be able to push it out more easily, the sprue 17 is enlarged inside the core part 1 by an annular groove 20. sprue 17, runner 16 and gate 14,
By configuring and arranging the gates 15 in this manner, the gates 14 and 15 that open to the individual cavities 5 and 6 can be made extremely short, and as mentioned above, the connection holes to the cavities 5 and 6 can be made extremely short. It can be made significantly thinner. In order to push out the surplus synthetic resin 18 that has hardened within the sprue 11, the core parts 1 and 2 are butted against each other at a dividing surface 21 at the center of the mold perpendicular to the axis of the sprue 17, so that they cannot be separated from each other in the axial direction. can. In this case, the dividing surface 21 is arranged between the cavities 5 and 6. Divided surface 21
With this arrangement, the frictional forces that must be overcome during mold cutting of the product can be minimized. Therefore, the excess synthetic resin 18 can be easily extruded. On the other side, the runner 16 will be located at the dividing surface 21, so that the production of the core is made very simple. By the way, when the plastic state Q synthetic resin is press-fitted from an injection nozzle (not shown) through the sublue 17, the synthetic resin fills all the hollow spaces, so that the two cages are coaxially inserted into the digital cavities 5 and 6. They are molded at the same time and spaced apart from each other. In order to remove the fully cured finished product, the core part 2 is first pulled axially away from the core part 1, and the excess synthetic resin in the gate 15 is then stripped off from the collar 12 of one of the cages. When the radially movable movable outer mold part 3 is then withdrawn outwardly, the two finished cages can be pushed out axially by the product machining sector 13 and removed. In this case, the gate 14 on the left side as seen in Figure 1
The surplus synthetic resin that has hardened inside the left Tsukuda p retainer collar 1
It can be easily removed from 1. The surplus synthetic resin 18 still retained by the annular groove 201fC can finally be pushed out by the working sector 19. All the synthetic resin press-fitted and cured in this way can be easily removed and the next injection molding process can be started immediately. As described above, in the present invention, at least two cavities are provided in which at least two cages are coaxially molded at a distance from each other at the same time, and the ribs of the at least two cages that are adjacent to each other at a distance from each other are provided. Since the molding surfaces of the end faces facing each other are provided on the radially movable outer mold part, the movable outer mold part molds the end faces of the collar at the same time as the rolling element receiving pocket of the cage. It is possible to at least double the production efficiency at a small cost without requiring a large number of movable mold parts, and to reduce the exclusive time of one injection molding machine by at least half or less, and with a simple structure. Therefore, it has remarkable effects such as making it extremely easy to cut out the product.

[Brief explanation of the drawing]

FIG. 1 is a partial vertical cross-sectional view of one embodiment of the present invention, and FIG. 2 is a partial cross-sectional view taken along the line -- in FIG. 1 and 2...core part, 3...movable outer mold part, 4...mold, 5 and 6...
・Cavity, 7 and 8...Original part, 9 and 10...End face (of retainer collar), 11 and 1
2...Brim (of cage), 13...Product engineering sector, 14 and 15...Gate, 16
...Runner, 17...Sprue, 18.
... Surplus synthetic resin, 19 ... Engineering sector,
20...Annular groove, 21...Divided surface.

Claims (1)

[Claims] 1. Cage made of synthetic resin for radial rolling bearing,
It is also a manufacturing device for a cage in which two annular ribs at both axial ends are connected to each other by a large number of axial columns uniformly distributed along the circumference. In a type comprising a cylindrical core having an outer diameter equal to the inner diameter of the cage, and a mold surrounding the core and having a number of radially movable outer mold parts, at least at least two cavities 5, 6 for molding two cages simultaneously and spaced apart from each other simultaneously;
are formed on the radially inner end face of the movable outer mold part 3, and the mutually facing end faces 9 of the mutually spaced adjacent flanges 11, 12 of the at least two retainers; 10 molding surfaces are provided in said movable outer mold part 3, each cavity 5, 6 having a gate 14, 15 respectively, which gates are connected to the core between the cavities 5, 6. It opens into a common runner 16 connected to a coaxial sprue 17, and the core is characterized in that it has a dividing plane 21 between the cavities 5, 6 at right angles to the axis of the sprue 17. Manufacturing equipment for synthetic resin cages for radial rolling bearings.