Top roller for a draft apparatus

• US 6,032,336 A
• Filed: 02/08/1999
• Issued: 03/07/2000
• Est. Priority Date: 03/05/1998
• Status: Expired due to Term

• Current Assignee: Murata Machinery Limited (Muratec)
• Original Assignee: Murata Machinery Limited (Muratec)
• Inventors: Fujiwara, Michiaki
• Primary Examiner(s): Calvert, John J.
• Assistant Examiner(s): Welch, Gary L.
• Application Number:
  US09/246,159
• Time in Patent Office: 393 Days
• Field of Search: 29/898.07, 29/898.09, 29/898.062, 29/898.064, 492/16, 492/38, 492/39, 492/42, 492/47, 384/517, 384/518, 384/563, 19/258, 19/236
• US Class Current: 19/258
• CPC Class Codes: D01H 5/74 Rollers or roller bearings
• CPC Class Codes: F16C 2340/18 Apparatus for spinning or twisting in general D01H
• CPC Class Codes: F16C 25/083 with resilient means acting axially on a race ring to preload the bearing

Abstract

When a roller cylinder of a top roller is installed, it may collide against an outer bearing and damage it. Since the roller cylinder is loosened, when drafting is executed at a high speed, the roller cylinder may vibrate, causing non-uniform drafting. A pre-loading spring 30 is installed between an inner bearing 20 and an outer bearing 21 and on the inner circumferential side. Due to the elastic force of the pressurizing spring 30, inner rings 20b and 21b of the bearings rotate integrally with a shaft 10. When the roller cylinder 12 is installed, if it collides against the outer bearing 21, the pre-loading spring 30 acts as a buffer to prevent damage to the bearings. O-rings 31 and 32 installed between outer rings 20a and 21a of the bearings 20 and 21 fill the gap to prevent the roller cylinder 12 from loosening. As a result, uniform drafting can be executed at a high speed.

Claims

1. A top roller for a draft apparatus for drawing a sliver comprising:

a shaft, a roller cylinder, a set of axially spaced bearings having inner and outer rings rotatably supporting said roller cylinder on said shaft, and an elastic member operative to press an inner ring of a bearing against a pressure-receiving section formed on said shaft.

2. A top roller for a draft apparatus according to claim 1 in which said elastic member is a spring.

3. A top roller for a draft apparatus according to claim 2 in which the inner ring of one of the bearings engages a pressure-receiving section formed at an end of said shaft, and the spring is installed between the inner rings of the bearings so as to press each of the bearings oppositely along a bearing surface of the shaft with the spring installed thereon.

4. A top roller for a draft apparatus according to claim 1 or claim 3 in which an axial pressure is applied to outer rings of said bearings to prevent them from loosening on said shaft.

5. A top roller for a draft apparatus according to claim 1 or claim 3 in which an O-ring applies an axial pressure to the outer ring of a bearing in order to prevent it from loosening on said shaft.