JPS6333982B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a grinding device used for simultaneously grinding the upper and lower surfaces of a workpiece.

Generally, the structure shown in FIGS. 1 and 2 is known as an example of the above-mentioned grinding device. That is,
This grinding device uses electric motors 1 and 2 to drive a transmission mechanism 3.
Grinding wheel heads 11 and 12 are mounted on a machine frame 13, and are made up of grinding wheels 9 and 10 attached to grinding wheel holders 7 and 8 provided at the ends of rotating shafts 5 and 6, which are rotated through rotating shafts 5 and 6. , 12 whetstones 9,
10 are provided in the middle of the machine frame 13 with their ground surfaces facing each other and are vertically opposed, and the upper rotating shaft 5 is driven by a drive device 14 operated by hydraulic pressure or pneumatic pressure via a rack or the like. The upper grindstone 9 is supported to be movable up and down, thereby pressing the upper grindstone 9 against the workpiece so that the workpiece is sandwiched between the two grindstones 9 and 10. The workpiece is transferred from the outer periphery of the grinding wheel on one side, through the center core of the grinding wheel, to the outer periphery of the grinding wheel on the opposite side, and in the process, the upper and lower surfaces of the workpiece are simultaneously ground. .

By the way, in the above-mentioned grinding device, the circumferential speed of the grinding surface of the grindstone gradually decreases from the outer periphery of the grindstone and reaches 0 at the center of the grindstone, so that effective grinding is performed at the outer periphery of the grindstone where the circumferential speed is high. However, in the center of the whetstone where the circumferential speed is low, effective grinding is not performed and only grinding resistance is applied to the workpiece, and in the case of small and thin workpieces, cracks occur at the center of the whetstone. However, there was a drawback.

In view of the above-mentioned drawbacks of conventional grinding devices, this invention
This was proposed in order to improve and eliminate this problem, and to provide a grinding device that allows the workpiece to be ground only on the effective grinding surface of the grindstone.

The grinding apparatus of the present invention will be explained below with reference to the drawings.

That is, as shown in FIG. 3, the grinding device of the present invention has a lower grindstone head 15 integrally formed at the upper end with a grindstone 16 formed into a donut shape with an effective grinding surface remaining at a constant width circumferentially from the outer periphery. The grindstone 16 is tightly fixed to the upper surface of the brim-shaped grindstone holder 17 with bolts 18, and a rotary body 21 is spline-fitted to the lower end of which a transmission pulley 19 is tightly fixed with bolts 20. A sleeve 22 , a fixed sleeve 25 in which the upper and middle parts of the rotating sleeve 22 are rotatably and coaxially supported inside by bearings 23 and 24 , and bolts 26 are attached to the machine frame 13 .
and the fixing sleeve 2
5 is tightly fitted and supported inside the rotary sleeve 22, and the lower end of the rotary sleeve 22 is rotatably supported by bearings 27, 27 via the rotating body 21, and the rotary sleeve 22 is are inserted concentrically, and the upper end is supported by a bearing 29,
Furthermore, a falling sleeve 31 is supported by a bracket 30 whose lower end is integrally attached and fixed to a part of the support sleeve 28, and a falling sleeve 31 is fitted into the center hole of the grinding wheel 16 and integrated with the upper end of the falling sleeve 31. The upper surface of the formed brim-shaped guide pedestal 32 is flush with the grinding surface of the grindstone 16 and is tightly fixed with a bolt 33, and a drop hole 34 for the workpiece is provided in the center core thereof, communicating with the drop sleeve 31. It is characterized by being configured with a guide 35 provided. The grinding device of the present invention has substantially the same construction as the conventional one except that the lower grindstone head 15 is constructed as described above, and a description thereof will be omitted.

In the grinding device configured as described above, in order to grind a workpiece, the grindstone 9 of the upper grindstone head 11 is rotated by an electric motor (not shown) as in the conventional case, and at the same time, the grindstone 16 of the lower grindstone head 15 is rotated. The transmission pulley 19 is driven by an electric motor (not shown).
The workpiece is rotated through the rotating body 21 and the rotating sleeve 22, and the workpiece is transferred between the two grindstones 9 and 16 of the upper and lower grindstone heads 11 and 15, and the upper and lower surfaces of the workpiece are transferred to the upper and lower grindstone heads 11 and 15, respectively. Grinding is performed using both grindstones 9 and 16 of No. 15. The workpiece is placed between the upper and lower grinding wheels 9, 15 and 15.
When the grinding is completed on the effective grinding surface portion of the lower grinding wheel 16, the falling sleeve 3 is fitted into the center hole of the lower grinding wheel 16.
The drop hole 34 of the guide 35 provided at the upper end of 1
It falls downward from the drop sleeve 31 and is extracted to an arbitrary position. In this case, the workpiece is ground only on the effective grinding surface of the grindstone, so
Large grinding resistance is not applied to the workpiece, and cracks do not occur even when the workpiece is small and thin. In addition, since the guide 35 and falling sleeve 31 are always stationary during processing,
The product is smoothly discharged from the system without damaging the edges or the grinding surface.

As explained above, the present invention has a donut-shaped grindstone on the upper end surface in a hollow fixed sleeve that is fixedly supported on the machine frame via the support sleeve, and a transmission pulley on the outer periphery of the lower end. A hollow falling sleeve is disposed within the rotating sleeve, the lower end of which is fixedly supported by a bracket extending from the supporting sleeve, and on the upper end surface of the falling sleeve,
Since the guide is arranged so as to be located in the center hole of the grinding wheel and has a drop hole that coincides with the hollow hole of the drop sleeve, it is possible to prevent the occurrence of cracks in the product and also to prevent the product from cracking. It can exhibit a particularly remarkable effect of being able to be discharged out of the system smoothly and without damage.

[Brief explanation of the drawing]

1 and 2 are front and side views schematically showing this type of grinding device, and FIG. 3 is a detailed longitudinal sectional view of the lower grindstone head of the grinding device according to the present invention. 9... Upper whetstone, 11... Upper whetstone head, 1
3...Machine frame, 15...Lower grinding wheel head,
16... lower whetstone, 17... whetstone holder, 19...
Transmission pulley, 21... Rotating body, 22... Rotating sleeve, 25... Fixed sleeve, 28... Supporting sleeve, 31... Falling sleeve, 32... Guide pedestal, 35... Guide.

Claims (1)

[Claims] 1. A rotary sleeve that has a donut-shaped grindstone on the upper end surface and a transmission pulley on the outer peripheral surface of the lower end is rotatable in a hollow fixed sleeve that is fixedly supported on the machine frame via a support sleeve. A hollow falling sleeve whose lower end is fixedly supported by a bracket extending from the supporting sleeve is disposed within the rotating sleeve, and a hollow falling sleeve is positioned on the upper end surface of the falling sleeve within the center hole of the grinding wheel. A grinding device characterized in that a guide is fixedly arranged and has a drop hole that matches the hollow hole of the drop sleeve.