Rotary die cutter apparatus and method

• US 20020133951A1
• Filed: 04/03/2002
• Published: 09/26/2002
• Est. Priority Date: 10/10/2000
• Status: Active Grant

• Current Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Original Assignee: Kimberly-Clark Worldwide Incorporated (Kimberly-Clark Corporation)
• Inventors: Beduhn, Mark W.
• Granted Patent: US 6,588,107 B2
• Time in Patent Office: Days
• US Class Current: 29/898.07
• CPC Class Codes: B26D 7/2614 Means for mounting the cutting member
• CPC Class Codes: B26D 7/265 Journals, bearings or supports for positioning rollers or cylinders relatively to each other
• CPC Class Codes: F16C 2229/00 Setting preload
• CPC Class Codes: F16C 25/06 Ball or roller bearings
• CPC Class Codes: Y10T 29/49696 Mounting
• CPC Class Codes: Y10T 29/497 Pre-usage process, e.g., preloading, aligning
• CPC Class Codes: Y10T 29/49766 torquing threaded assemblage or determining torque herein
• CPC Class Codes: Y10T 29/49769 Using optical instrument [excludes mere human eyeballing]
• CPC Class Codes: Y10T 29/49771 Quantitative measuring or gauging
• CPC Class Codes: Y10T 29/53061 Responsive to work or work-related machine element
• CPC Class Codes: Y10T 29/53087 with signal, scale, illuminator, or optical viewer

Abstract

Apparatus and method precisely preload bearings onto shafts. A swivel plate swivels up to 360° and locks a rotary shaft axially with a motor shaft. A shim and bearing adjacent the shim preload onto shaft shoulder by lock nut secured to the threaded shaft. The lock nut forces the bearing inner race to expand outwardly, preloading the bearing. A force sensor measures torque on the bearing outer race. Measured torque is monitored within a predetermined range to establish the precisely loaded bearing. The method slides a shim onto support shaft shoulder. A bearing is slid onto tapered surface, and lock nut tightened onto the threaded shaft. The lock nut expands the bearing inner race, reducing the distance between the inner and outer races and preloading the bearing. The outer race at a predetermined, constant speed has torque monitored to a predetermined range to provide a precisely preloaded bearing.

Claims

1. An apparatus for precisely preloading a bearing onto a shaft, comprising:

a) a baseplate;

b) a support mounted to said base plate and extending upward from said base plate, said support capable of supporting a shaft having a shoulder, a tapered surface adjacent to said shoulder, and a threaded portion adjacent to said tapered surface, and a shim positioned on said shaft adjacent to said shoulder, a bearing positioned adjacent to said shim, said bearing having an inner race, an outer race, and a plurality of roller elements positioned between said inner race and outer race, and a lock nut secured to said threaded portion of said shaft which contacts and preloads said inner race of said bearing;

c) a motor mounted to said base plate, said motor having an output shaft axially aligned with and connectable to said outer race of said bearing, said motor capable of rotating said outer race of said bearing at a predetermined speed;

d) a force sensor attached to said motor capable of measuring the amount of torque required to rotate said outer race at a predetermined speed;

e) display means for providing a visual readout of said measured torque; and

f) a swivel plate attached rotatably to the upper surface of the base plate, wherein said supports are attached to said swivel plate.

2. The apparatus of claim 1, wherein said swivel plate swivels up to 360°

on said base plate.

3. The apparatus of claim 1, wherein said swivel plate has a locking mechanism to retain said shaft in an axial relationship with said motor output shaft.

4. The apparatus of claim 3, wherein said locking mechanism comprises at least one pull-type plunger spring loaded into a down or lock position.

5. The apparatus of claim 4, wherein said locking mechanism is operated by a mechanical, electrical, hydraulic, or pneumatic means.

6. The apparatus of claim 4, wherein said locking mechanism comprises a pull-type plunger with a pivot pin mechanism positioned to nest in an aperture formed in said base plate.

7. The apparatus of claim 6, wherein said pull-type plunger is spring activated.

8. The apparatus of claim 6, wherein said motor is a constant speed air motor.

9. The apparatus of claim 8, wherein said force sensor is a load cell.

10. A method of precisely preloading a rotary die cutter shaft bearing, comprising:

a) supporting a rotary die cutter shaft having a shoulder, a tapered surface adjacent to said shoulder, and a threaded portion adjacent to said tapered surface;

b) sliding a first shim onto said rotary die cutter shaft until said first shim abuts said shoulder, said first shim having a predetermined thickness;

c) sliding a spherical bearing onto said tapered surface, said-spherical bearing having an inner race, an outer race and a plurality of roller elements positioned between said inner race and said outer race;

d) expanding said inner race by tightening a lock nut onto said threaded portion of said rotary die cutter shaft to expand said inner race and force said inner race into contact with said first shim, thereby preloading said spherical roller bearing;

e) connecting said outer race of said spherical bearing to a motor and operating said motor at a predetermined speed;

f) measuring the torque required to rotate said outer race of said spherical bearing;

g) comparing said measured torque to a predetermined torque range to determine if said spherical bearing is precisely preloaded; and

h) providing a swivel plate for retaining said rotary die cutter shaft in an axial relationship with said motor.

11. The method of claim 10, wherein said bearing comprises a reconditioned bearing.

12. The method of claim 10, wherein said providing a rotary die cutter shaft comprises providing a rotary die cutter shaft for a heavy rotary die cutter.

13. The method of claim 12, wherein said swivel plate can swivel up to 360 degrees for retaining said rotary die cutter shaft in an axial relationship with said motor.

14. The method of claim 13, wherein said swivel plate further comprises a pull type plunger locking mechanism for retaining said rotary die cutter shaft in an axial relationship with said motor.

15. The method of claim 14, comprising spring loading said pull type plunger in a down lock position.

16. The method of claim 15, comprising pulling up said pull type plunger from the down lock position and rotating said swivel plate about 180 degrees for axially aligning said opposite end rotary die cutter shaft bearing on the opposite end of said rotary die cutter shaft.

17. The method of claim 15, comprising pulling up said pull type plunger from the down lock position and rotating said swivel plate relative to said base plate.

18. The method of claim 15, comprising preloading a bearing on one side of said rotary die cutter and then pulling up said pull type plunger from the down lock position, rotating said swivel plate relative to said base plate to preload a bearing on an opposite side of said rotary die cutter.

19. The method of claim 15, wherein said bearing comprises a reconditioned bearing.

20. An apparatus for precisely preloading a bearing onto a shaft, comprising:

a) a baseplate;

b) a support mounted to said base plate and extending upward said base plate, said support capable of supporting a shaft;

c) a shaft having a shoulder, a tapered surface adjacent to said shoulder, and a threaded portion adjacent to said tapered surface;

d) a shim positioned on said shaft adjacent to said shoulder;

e) a bearing positioned adjacent to said shim, said bearing having an inner race, an outer race and a plurality of roller elements positioned there between

f) a lock nut secured to said threaded portion of said shaft which contacts and preloads said inner race of said bearing;

g) a constant speed air motor mounted to said base plate, said motor having an output shaft axially aligned with and connectable to said outer race of said bearing, said motor capable of rotating said outer race of said bearing at a predetermined speed;

h) a load cell force sensor attached to said motor capable of measuring the amount of torque required to rotate said outer race at a predetermined speed;

i) display means for providing a visual readout of said measured torque;

j) a swivel plate attached rotatably to the upper surface of the base plate, wherein said supports are attached to said swivel plate, wherein said swivel plate swivels up to 360°

on said base plate; and

k) a locking mechanism for retaining said shaft in an axial relationship with said motor output shaft, said locking mechanism comprising at least one pull-type plunger spring-loaded into a down or lock position and a pivot pin positioned to nest in an aperture formed in said base plate.