Split bobbin clutch for bypass plungers
A clutch assembly formed as a circular split bobbin assembly for resisting reciprocating motion of a shift rod or dart valve stem in a bypass plunger. The split bobbin may include at least one circumferential groove disposed in its outer radius, and a tension band member disposed in each circumferential channel to secure the split bobbin assembly around the shift rod or valve stem and wherein the tension band member has a cross section aspect ratio R<1.
1. A clutch assembly for resisting the reciprocating motion of a shift rod or dart valve stem in a bypass plunger, comprising:
a clutch body formed as a circular split bobbin assembly having first and second cylindrical halves;
at least one circumferential channel disposed in a surface defined by the outer radius of the split bobbin assembly; and
a tension band disposed in each circumferential channel to secure the split bobbin assembly around the shift rod or dart valve stem wherein the outer radius of each tension band is less than the outer radius of the split bobbin assembly and wherein each tension band has a gap in its circumference and a cross section aspect ratio R<1.
2. The clutch assembly of claim 1 , wherein the tension band comprises:
a circular member formed of metal wherein the aspect ratio R is defined by R=A÷B where A=thickness and B=width of the tension band.
3. The clutch assembly of claim 1 , wherein the tension band comprises:
a circular member formed of non-metallic material wherein the aspect ratio R is defined by R=A÷B where A=thickness and B=width of the tension band.
4. The clutch assembly of claim 1 , wherein the circumferential channel comprises:
a cut out portion disposed around the outer circumference of the split bobbin halves and having a U-shaped cross section of sufficient depth to receive one or more tension bands therein.
5. The clutch assembly of claim 1 , further comprising:
at least first and second circumferential channels each having a tension band disposed therein.
6. The clutch assembly of claim 1 , further comprising:
at least first and second circumferential channels each having one or more tension bands disposed therein.
7. The clutch assembly of claim 1 , further comprising:
at least three circumferential channels surrounding the outer circumference of the split bobbin for receiving one or more tension bands disposed therein.
8. A clutch assembly for resisting the reciprocating motion of a shift rod or dart valve stem in a bypass plunger, comprising:
a clutch body formed as a circular spilt bobbin assembly having first and second cylindrical halves;
at least one circumferential channel disposed in a surface defined by the outer radius of the split bobbin assembly; and
at least first and second tension bands stacked in each circumferential channel to secure the spilt bobbin assembly around the shift rod or dart valve stem;
wherein each tension band includes a gap in its circumference and a cross section aspect ratio R<1.