Methods for manufacturing pump-heads having a desired internal clearance for rotary member
Various methods are disclosed for manufacturing pump-heads having a housing enclosing at least one rotary member. In an exemplary method first and second housing portions are provided that collectively, when assembled, define a pump-cavity that accommodates the rotary member(s). The rotary member(s) is assembled into the pump-cavity, along with at least one soluble spacer of a defined thickness that corresponds to a desired clearance of the rotary member relative to the pump-cavity. The spacer contacts a surface of the rotary member facing a corresponding surface of the housing portion. The first and second housing portions are attached together to form the pump-cavity containing the rotary member(s). The soluble spacer is dissolved to provide the desired clearance of the rotary member in the pump-cavity. As the housing portions are attached together, e.g., by adhesive bonding, the spacer establishes the desired clearance of the rotary member(s) in the pump-cavity.
1. A method for manufacturing a pump-head including a housing enclosing at least one rotary member, the method comprising:
providing a first housing portion and a second housing portion that collectively, when assembled together, define a pump-cavity that accommodates the at least one rotary member;
assembling the at least one rotary member into the housing portions;
placing a soluble spacer of a defined thickness, corresponding to a desired clearance, in contact with a surface of the at least one rotary member facing a corresponding surface of at least one of the housing portions;
attaching the first and second housing portions together to form the pump-cavity containing the at least one rotary member; and
dissolving the soluble spacer to provide the desired clearance of the at least one rotary member in the pump-cavity.
2. The method of claim 1 , wherein the attaching step comprises urging the first and second housing portions toward each other to establish a specified preload to the housing until stopped by the soluble spacer.
3. The method of claim 1 , wherein:
the at least one rotary member comprises multiple pump gears; and
the assembling step comprises mounting the pump gears in the pump-cavity before attaching the first and second housing portions together.
4. The method of claim 1 , wherein the desired clearance is a desired end-clearance of the at least one rotary member relative to a corresponding location on an inside surface of the pump-cavity.
5. The method of claim 1 , wherein:
the at least one rotary member comprises first and second gears intermeshed with each other in the pump-cavity; and
the desired clearance is a desired end-clearance of the gears relative to corresponding locations on an inside surface of the pump-cavity.
6. The method of claim 5 , wherein placing the soluble spacer comprises placing a soluble washer coaxially with a respective gear to establish the desired end-clearance between a side of the gear and the corresponding inside surface of the pump-cavity.
7. The method of claim 1 , wherein the attaching step comprises bonding the first and second housing portions together.
8. The method of claim 7 , wherein bonding comprises:
applying adhesive to mating surfaces of the first and second housing portions; and
after attaching the first and second housing portions together, curing the adhesive.
9. The method of claim 8 , further comprising applying a preload to the first and second housing portions before curing the adhesive.
10. The method of claim 1 , further comprising mounting a rotation device to the pump-head such that the rotation device is coupled to the at least one rotary member, the rotation device being energizable in a manner causing rotation of the at least one rotary member in the pump-cavity.
11. The method of claim 10 , wherein:
the rotation device comprises a rotatable magnet coupled to at least one rotary member and a magnet driver magnetically coupled to the rotatable magnet; and
the assembling step comprises enclosing the magnet in a magnet cup and mounting the magnetic cup to at least one of the housing portions such that the magnet cup is in hydraulic communication with the pump-cavity.
12. The method of claim 1 , wherein dissolving comprises circulating a solvent in the pump-cavity to dissolve the spacers.
13. The method of claim 12 , further comprising rotating the at least one rotary member while circulating the solvent.
14. A method for manufacturing a gear pump-head, comprising:
providing a first housing portion and a second housing portion that collectively, when assembled, define a gear-cavity;
assembling a driving gear and a driven gear into the housing portions;
placing a soluble spacer, having a defined thickness corresponding to a desired end-clearance, in contact with at least one surface of the gears facing at least one of the housing portions in the gear cavity;
attaching the first and second housing portions together to form the gear-cavity containing the gears, the attaching including urging the first and second housing portions toward each other until stopped by the soluble spacer; and
dissolving the soluble spacer to provide the desired end-clearance of the gears in the gear-cavity.
15. The method of claim 14 , further comprising:
applying adhesive to mating surfaces of the first and second housing portions; and
after attaching the first and second housing portions together, curing the adhesive.
16. The method of claim 14 , further comprising:
mounting a rotatable magnet to the driving gear; and
enclosing the magnet in a magnet cup mounted to at least one of the housing portions.