Portable brinell hardness tester

Abstract

A portable Brinell metal hardness tester has a test head mounted in a carriage, movable vertically along elevating screws, and includes an adjustable valve for relieving hydraulic pressure within the test head where the valve includes a stem, an interior member, and an intermediate member.

The following is claimed: 
     
         1 . A portable Brinell metal hardness tester comprising:
 (a) a carriage movable vertically along elevating screws;   (b) a test head, mounted in the carriage, for applying preselected force to a test piece including:
 i) a reciprocable pumping plunger for supplying hydraulic fluid pressure to a ball contacting the test piece, the pumping plunger having a rack formed therein; 
 ii) a rotatable gear engaging the rack, for imparting longitudinal motion to the plunger upon rotation of the gear; 
 iii) a pressure release valve for releasing hydraulic fluid pressure when desired, comprising:
 (1) a handle, extending outwardly from the test head for opening and closing the release valve, comprising:
 (A) a ring-like portion receivingly gripping a shaft portion of the pressure release valve; 
 (B) an intermediate portion connected to the ring-like portion; 
 (C) a blade portion, connected to the intermediate portion, of upstanding planar configuration. 
 
 
   (c) a manually movable lever connected to the gear and being rotatable therewith, pivotally mounted on the test head exterior, for imparting rotary movement about the axis of rotation of the gear; and   (d) a stop, connected to the carriage and positioned to contact the lever at a predetermined position of lever angular movement, for limiting lever angular travel and thereby limiting angular movement of the gear to a preselected amount.   
     
     
         2 . The portable Brinell metal hardness tester of  claim 1  wherein the pressure release valve handle has a planar lower surface for facing slidable contact with a planar exterior surface of the test head. 
     
     
         3 . The portable Brinell metal hardness tester of  claim 1  wherein the ring-like and intermediate portions have planar upper surfaces that are parallel with the lower surface. 
     
     
         4 . The portable Brinell metal hardness tester of  claim 1  wherein the intermediate and ring-like portions extend upwardly from the lower surface a common distance. 
     
     
         5 . The portable Brinell metal hardness tester of  claim 1  wherein the blade portion further comprises:
 (a) a vertically extending edge surface proximate the ring-like portion; 
 (b) a second vertically extending edge surface at an extremity remote from the ring-like portion, the second vertically extending edge surface being longer than the first vertically extending edge surface; and 
 (c) extremities of the first and second vertically extending edges remote from the planar lower surface being connected by a straight edge. 
 
     
     
         6 . The portable Brinell metal hardness tester of  claim 1  wherein the stop further comprises:
 (a) an elongated blade member facingly contactingly connected to the carriage; 
 (b) a lever travel limiting member extending perpendicularly from the blade member proximate one end thereof to interfere with the lever upon the lever exceeding a preselected amount of angular travel from a starting position; 
 (c) the blade member being at a preselected angle to position the lever travel limiting member at a pre-designated position to limit lever angular travel from the starting position. 
 
     
     
         7 . The portable Brinell metal hardness tester of  claim 6  wherein the lever travel limiting member is cylindrical with an axis perpendicular to the blade member and to a geometric plane in which the lever travels. 
     
     
         8 . A portable Brinell metal hardness tester comprising:
 (a) a carriage movable vertically along elevating screws;   (b) a test head, mounted in the carriage, for applying preselected force to a test piece, including:
 i) a reciprocable pumping plunger for supplying hydraulic fluid pressure to a ball contacting the test piece, the pumping plunger having a rack formed therein; 
 ii) a rotatable gear engaging the rack, for imparting longitudinal motion to the plunger upon rotation of the gear; 
 iii) a pressure relief valve comprising:
 (1) a stem having first and second ends, the first end fitting against the ball as the ball contacts the valve seat, the stem residing within the passageway; 
 (2) a spring interposed between and contacting the first and second ends of the stem; 
 (3) an interior member having a first end contacting the second end of the stem and a second end adapted to receive a wrench, the interior member first end having external threads for engagement with the threaded passageway, rotation of the interior member moving the interior member axially within the passageway to compress or decompress the spring between the stem first and second ends according to direction of interior member movement thereby to increase or decrease force on the ball applied thereto by the stem first end. 
 
   (c) a manually movable lever connected to the gear and being rotatable therewith, pivotally mounted on the test head exterior, for imparting rotary movement about the axis of rotation of the gear; and   (d) a stop, connected to the carriage and positioned to contact the lever at a predetermined position of lever angular movement, for limiting lever angular travel and thereby limiting angular movement of the gear to a preselected amount.   
     
     
         9 . The portable Brinell metal hardness tester of  claim 8  wherein the stop further comprises:
 (a) an elongated blade member facingly contactingly connected to the carriage; 
 (b) a lever travel limiting member extending perpendicularly from the blade member proximate one end thereof to interfere with the lever upon the lever exceeding a preselected amount of angular travel from a starting position; 
 (c) the blade member being at a preselected angle to position the lever travel limiting member at a pre-designated position to limit lever angular travel from the starting position. 
 
     
     
         10 . The portable Brinell metal hardness tester of  claim 8  wherein the pressure relief valve further comprises:
 (a) an intermediate sleeve member having external threads for engaging the threaded passageway, with a central passageway slidably receiving the interior member upon rotation of the interior member moving the interior member axially within the threaded passageway. 
 
     
     
         11 . The portable Brinell metal hardness tester of  claim 10  wherein the intermediate sleeve member external threads are first external threads located proximate an intermediate member first end and the intermediate sleeve member has a second end sized for sliding passage through the threaded passageway. 
     
     
         12 . The portable Brinell metal hardness tester of  claim 11  further comprising a cap fitting on the second end of the intermediate member. 
     
     
         13 . A portable Brinell metal hardness tester comprising:
 (a) a carriage movable vertically along elevating screws;   (b) a test head, mounted in the carriage, for applying preselected force to a test piece, the test head comprising:
 i) a pressure release valve for releasing hydraulic fluid pressure when desired, comprising:
 (1) a handle extending outward from the test head for opening and closing the release valve, comprising:
 (A) a ring-like portion receivingly gripping a shaft portion of the pressure release valve; 
 (B) an intermediate portion connected to the ring-like portion; 
 (C) a blade portion connected to the intermediate portion, of upstanding planar configuration; and 
 
 
 ii) a pressure relief valve comprising:
 (1) a stem having first and second ends; 
 (2) a spring interposed between and contacting the first and second ends of the stem; 
 (3) an interior member having a first end contacting the second end of the stem and a second end adapted to receive a wrench, the interior member first end having external threads for engagement with a threaded passageway within which the interior member resides, rotation of the interior member moving the interior member axially within the passageway to compress or decompress the spring between the stem first and second ends according to direction of interior member movement thereby to increase or decrease force on a ball applied thereto by the stem first end. 
 
   
     
     
         14 . The portable Brinell metal hardness tester of  claim 13  wherein the pressure relief valve further comprises:
 (a) an intermediate sleeve member having external threads for engaging the threaded passageway, with a central passageway slidably receiving the interior member upon rotation of the interior member moving the interior member axially within the threaded passageway. 
 
     
     
         15 . The portable Brinell metal hardness tester of  claim 14  wherein the pressure relief valve intermediate sleeve member external threads are first external threads located proximate an intermediate member first end; the intermediate sleeve member having a second end sized for sliding passage through the threaded passageway. 
     
     
         16 . The portable Brinell metal hardness tester of  claim 15  wherein the pressure relief valve valve further comprises a cap for fitting on an end of the intermediate member. 
     
     
         17 . The portable Brinell metal hardness tester of  claim 13  wherein the pressure release valve handle has a planar lower surface in facing slidable contact with a planar exterior surface of the test head. 
     
     
         18 . The portable Brinell metal hardness tester of  claim 13  wherein the ring-like and intermediate portions of the pressure release valve handle have planar upper surfaces that are parallel with the lower surface. 
     
     
         19 . The portable Brinell metal hardness tester of  claim 13  wherein the pressure release valve blade portion is of uniform transverse thickness. 
     
     
         20 . The portable Brinell metal hardness tester of  claim 13  wherein the common distance the intermediate and ring-like portions extend upwardly from the lower surface is greater than transverse thickness of the blade portion.