Plastic Ring for Removably Fixing a Round Shank Chisel in a Chisel Bush

• US 20080308981A1
• Filed: 03/31/2006
• Published: 12/18/2008
• Est. Priority Date: 04/14/2005
• Status: Abandoned Application

• Current Assignee: Erich Sattler, Robert Exel
• Original Assignee: Erich Sattler, Robert Exel
• Inventors: Exel, Robert
• Application Number:
  US11/918,348
• Publication Number:
  US 20080308981A1
• Time in Patent Office: Days
• US Class Current: 267/292
• CPC Class Codes: E21C 35/197 using sleeves, rings or the like, as main fixing elements

Abstract

A plastic ring (9) for detachably fixing a rounded-shaft tool (1) into a tool bushing (6), wherein the inside of the tool bushing (6) has an annular groove (7), into which the elastic plastic ring (9) held in an annular groove (3) of the tool shaft (2) engages, is designed in a slotted fashion and has at least one rib projecting beyond the outer surface of the plastic ring (9) and extending across at least a portion of the periphery of the plastic ring (9). In order to achieve a proper hold of the rounded-shaft tool (1), the cross-section of the plastic ring (9) exhibits a section (11) which can be pushed inwards and springs outwards in a radial direction and extends across at least a portion of the periphery of the plastic ring (9), wherein said section (11) can be pushed relative to the other sections of the cross-section of the plastic ring (9) from a relaxed initial position with a particular outside diameter (12) larger than the inside diameter (6′) of the tool bushing (6) into a fitting position exhibiting a smaller outside diameter corresponding to the inside diameter (6′) of the tool bushing (6) and is able to spring back into the relaxed initial position, whereby the total thickness (15) of the relaxed plastic ring (9) exceeds the depth (4) of the annular groove (3) of the tool shaft (2).

Claims

1. A plastic ring (9) for detachably fixing a rounded-shaft tool (1) into a tool bushing (6), wherein the inside of the tool bushing (6) has an annular groove (7), into which the elastic plastic ring (9) held in an annular groove (3) of the tool shaft (2) engages, with the plastic ring (9) being designed in a slotted fashion and having at least one rib projecting beyond the outer surface of the plastic ring (9) and extending across at least a portion of the periphery of the plastic ring (9), characterized in that the cross-section of the plastic ring (9) exhibits a section (11, 17) which can be pushed inwards and springs outwards in a radial direction and extends across at least a portion of the periphery of the plastic ring (9), wherein said section (11, 17) can be pushed relative to the other sections of the cross-section of the plastic ring (9) from a relaxed initial position with a particular outside diameter (12) larger than the inside diameter (6′

) of the tool bushing (6) into a fitting position exhibiting a smaller outside diameter corresponding to the inside diameter (6′

) of the tool bushing (6) and is able to spring back into the relaxed initial position, whereby either the total thickness (15) of the relaxed plastic ring (9) exceeds the depth (4) of the annular groove (3) of the tool shaft (2) or the slot (14) has a width (20) which is dimensioned such that, with a reduction in the diameter of the plastic ring (9) until the side walls of the slot (14) contact each other, the radially elastic section (11, 17) of the cross-section of the plastic ring (9) projects beyond the outside diameter of the tool shaft (2) when the plastic ring (9) is inserted in the annular groove (3).

2. A plastic ring (9) according to claim 1, characterized in that its cross-section has a wavelike design, wherein a wave crest projecting radially outwards forms the section (11) of the cross-section of the plastic ring (9) which springs inwards and outwards in a radial direction.

3. A plastic ring (9) according to claim 1, characterized in that it is provided with a radially projecting rib (17) which forms the section of the cross-section of the plastic ring (9) which can be pushed inwards and springs outwards in a radial direction.

4. A plastic ring (9) according to claim 3, characterized in that the rib (17) is designed so as to be inclined obliquely to the axis of the plastic ring (9), preferably at an angle of between 35 and 75°

.

5. A plastic ring (9) according to claim 1, characterized in that the section (11, 17) which can be pushed inwards and springs outwards in a radial direction extends across only a portion of the periphery of the plastic ring (9), preferably across at least 80% of the periphery.

6. A plastic ring (9) according to claim 1, characterized in that its wall thickness (14) ranges between 0.7 and 3 mm, preferably between 1.3 and 1.8 mm, wherein, in case a rib (17) projecting radially outwards has been designed, said rib has a smaller wall thickness (18) than the remaining cross-section of the plastic ring.

7. A plastic ring (9) according to claim 1, characterized in that it is formed from one of the following materials:

polyamide (PA), polyacetal (POM), thermoplastic polyesters (PET), HT-polymers (PEEK, PSU), polyethylene (PE);

polypropylene (PP), polyvinyl chloride (PVC).

8. A plastic ring (9) according to claim 1, characterized in that it is designed with a fiber reinforcement, for example, a glass fiber reinforcement.