Pump rod and driving link with side-load reducing configuration

Patent metadata

Field	Value
Publication number	US-2016186743-A1
Application number	US-201514984212-A
Country	US
Kind code	A1
Filing date	Dec 30, 2015
Priority date	Dec 30, 2014
Publication date	Jun 30, 2016
Grant date	—

Abstract

A pump rod has a head extending from a neck, and the head is received within a drive slot of a drive link. The head includes a projection, and has an area smaller than an area of the head. The projection contacts an inner surface of the drive slot. The drive link may include a projection aligned with a centerline of the drive link. The drive link projection contacts a head of the pump rod. The projections provide a reduced contact area between the pump rod and the drive link, thereby reducing any side-loading on the pump rod and increasing a lifespan of the wear parts.

First claim

1 . A pump rod comprising:
a shaft having a first end and a second end; a head attached to the first end; and a load concentrating feature attached to and projecting from a top surface of the head; wherein a load concentrating feature area is smaller than a head area.

2 . The pump rod of claim 1 , wherein the load concentrating feature comprises, a cylindrical projection extending from the head.

3 . The pump rod of claim 1 , wherein the first end further comprises:
a neck extending between and connecting the head and the shaft, wherein a neck width is smaller than a head width.

4 . The pump rod of claim 3 , wherein the neck further comprises:
a first fillet at a connection between the head and the neck; and a second fillet at a connection between the neck and the shaft.

5 . The pump rod of claim 1 , wherein the load concentrating feature is aligned with a centerline of the pump rod.

6 . The pump rod of claim 1 , wherein the head includes an anti-rotation feature disposed on a periphery of the head.

7 . The pump rod of claim 6 , wherein the anti-rotation feature comprises a flat surface.

8 . A driving system for a displacement pump comprising:
a pump rod comprising:
a shaft having a first end and a second end;
a head extending from the first end; and
a load concentrating feature attached to and projecting from a top surface of the head; and
a driving link comprising:
a cylinder having a first end and a second end;
a cavity extending into the first end; and
a U-shaped flange extending into the cavity, wherein the cavity is configured to receive the head of the pump rod and the U-shaped flange is configured to secure the head within the cavity.

9 . The driving system of claim 8 , wherein a load concentrating feature area is smaller than a head area.

10 . The driving system of claim 8 , wherein the load concentrating feature comprises a cylindrical projection.

11 . The driving system of claim 8 , and further comprising:
a neck disposed between and connecting the shaft and the neck, wherein a neck width is smaller than a head width.

12 . The driving system of claim 11 , wherein the neck further comprises:
a first fillet disposed at a connection between the head and the neck; and a second fillet disposed at a connection between the shaft and the neck.

13 . The driving system of claim 8 , and further comprising:
a connecting rod having a free end and a retained end, the retained end extending into the second end of the driving link through a drive opening in the second end; wherein the free end contains an aperture configured to receive a crank extending from a motor; and wherein the retained end is pinned within the second end of the driving link.

14 . The pump rod of claim 8 , wherein the head includes an anti-rotation feature.

15 . The pump rod of claim 14 , wherein the anti-rotation feature comprises a flat surface disposed on a side of the head.

16 . A driving link for a displacement pump comprising:
a body having a first end and a second end; a cavity extending laterally into the first end, the cavity comprising:
a forward-facing opening;
a lower opening; and
a contact surface disposed opposite the lower opening; and
a load concentrating feature projecting from the contact surface and into the cavity.

17 . The driving link of claim 16 , wherein the load concentrating feature comprises a cylindrical projection.

18 . The driving link of claim 16 , and further comprising:
a connecting slot extending into the second end, the connecting slot configured to receive a connecting rod for driving the driving link.

19 . The driving link of claim 16 , and further comprising:
a U-shaped flange extending about the lower opening of the cavity and projecting into the cavity.

20 . The driving link of claim 16 , wherein the cavity further comprises:
a first flat wall extending into the cavity from the forward-facing opening; a second flat wall extending into the cavity from the forward-facing opening; and a curved side extending between and connecting the first flat wall and the second flat wall; wherein the first flat wall and the second flat wall are configured to engage anti-rotation features on a pump rod to prevent rotation of the pump rod.

Assignees

• Graco Minnesota Inc

Inventors

• Thompson David J
• Lins Christopher A
• Kopel Andrew J
• Davidson Glen W
• Taszarek Chad R
• Sydow Chris W
• Blenkush William M
• Wrobel Steve J

Classifications

• F04B15/02

  the fluids being viscous or non-homogeneous · CPC title

• F04B17/03

  driven by electric motors · CPC title

• F04B53/22 Primary

  Arrangements for enabling ready assembly or disassembly · CPC title

• F04B53/16

  Casings; Cylinders; Cylinder liners or heads; Fluid connections · CPC title

• F04B53/144 Primary

  Adaptation of piston-rods · CPC title