Hydraulic shearing machine

Claim 2

A hydraulic shearing machine comprising a fixed knife and a movable knife operative to engage opposite sides of longitudinally adjacent sections of a bar or the like to be sheared; a yieldable back support member opposite said movable knife operative to move with the latter during the shearing operation; a hold down member opposite said fixed knife operative to hold the bar in fixed position against said fixed knife during shearing movement of said movable knife; parallel connected fluid motors operative to move said movable knife and said hold down member toward and away from the bar; pump means and directional control valve means operatively connected to said fluid motors to actuate them by substantially equal fluid pressures to apply hold down force proportional to the shearing force as applied by said knife actuating motor; and a fluid motor operatively connected to said back support member and having fluid communication with the fluid pressure line between said pump means and said directional control valve means whereby the back support force is also proportional to the shearing and hold down forces.

Claim 3

A hydraulic shearing machine comprising a fixed knife and a movable knife operative to engage opposite sides of longitudinally adjacent sections of a bar or the like to be sheared; a yieldable back support member opposite said movable knife operative to move with the latter during the shearing operation; a hold down member opposite said fixed knife operative to hold the bar in fixed position against said fixed knife during shearing movement of said movable knife; parallel connected fluid motors operative to move said movable knife and said hold down member toward and away from the bar; pump means and directional control valve means operatively connected to said fluid motors to actuate them by substantially equal fluid pressures to apply hold down force proportional to the shearing force as applied by said knife actuating motor; said pump means comprising a dual pump system including a low pressure-high volume pump, and a high pressure-low volume pump operatively connected to supply fluid under pressure to said directional control valve means, an unloading valve means to unload said low pressure-high volume pump in response to pressure rise at said directional control valve means to a predetermined value, and check valve means between said low pressure-high volume pump and said directional control valve means to permit flow of fluid from both of said pumps to said directional control valve for rapid advance and retraction of said movable knife and hold down member and to isolate said pumps from each other for high pressure actuation of said movable knife and said hold down member when they are engaged with the bar; said machine having another fluid motor operatively connected to said back support member with a port of said another fluid motor in fluid communication with said high pressure-low volume pump to provide a back support force proportional to the shearing force exerted by said movable knife.

Claim 4

A hydraulic shearing machine comprising a fixed knife and a movable knife operative to engage opposite sides of longitudinally adjacent sections of a bar or the like to be sheared; a yieldable back support member opposite said movable knife operative to move with the latter during the shearing operation; a hold down member opposite said fixed knife operative to hold the bar in fixed position against said fixed knife during shearing movement of said movable knife; parallel connected fluid motors operative to move said movable knife and said hold down member toward and away from the bar; pump means and directional control valve means operatively connected to said fluid motors to actuate them by substantially equal fluid pressures to apply hold down force proportional to the shearing force as applied by said knife actuating motor; said pump means comprising a dual pump system including a low pressure-high volume pump, and a high pressure-low volume pump operatively connected to supply fluid under pressure to said directional control valve means, an unloading valve means to unload said low pressure-high volume pump in response to pressure rise at said directional control valve means to a predetermined value, and check valve means between said low pressure-high volume pump and said directional control valve means to permit flow of fluid from both of said pumps to said directional control valve for rapid advance and retraction of said movable knife and hold down member and to isolate said pumps from each other for high pressure actuation of said movable knife and said hold down member when they are engaged with the bar; said machine having another fluid motor operatively connected to said back support member with a port of said another fluid motor in fluid communication with said high pressure-low volume pump to provide a back support force proportional to the shearing force exerted by said movable knife.

Claim 5

The machine of claim 2 wherein said directional control valve means comprises a four way valve having a neutral position to bypass the output of both pumps to a reservoir and has operating positions to selectively actuate said movable knife and hold down member fluid motors to advance or retract said knife and hold down member with respect to the bar.

Claim 6

The machine of claim 3 wherein said system has a relief valve in fluid communication with said high pressure-low volume pump to relieve excess fluid pressure in said movable knife, hold down member, and back support member fluid motors to a reservoir when said four way valve is in one of its operating positions.

Claim 7

A hydraulic shearing machine comprising a fixed knife and a movable knife operative to engage opposite sides of longitudinally adjacent sections of a bar or the like to be sheared; a yieldable back support member opposite said movable knife operative to move with the latter during the shearing operation; a hold down member opposite said fixed knife operative to hold the bar in fixed position against said fixed knife during shearing movement of said movable knife; parallel connected fluid motors operative to move said movable knife and said hold down member toward and away from the bar; pump means and directional control valve means operatively connected to said fluid motors to actuate them by substantially equal fluid pressures to apply hold down force proportional to the shearing force as applied by said knife actuating motor; said pump means comprising a dual pump system including a low pressure-high volume pump, and a high pressure-low volume pump operatively connected to supply fluid under pressure to said directional control valve means, an unloading valve means to unload said low pressure-high volume pump in response to pressure rise at said directional control valve means to a predetermined value, and check valve means between said low pressure-high volume pump and said directional control valve means to permit flow of fluid from both of said pumps to said directional control valve for rapid advance and retraction of said movable knife and hold down member and to isolate said pumps from each other for high pressure actuation of said movable knife and said hold down member when they are engaged with the bar; said machine having a back gage member which is adapted to be engaged by the end of the bar to position it for cutting of a piece of predetermined length therefrom; and a fluid motor operatively connected with said back gage member to retract the latter for endwise movement of a cut piece of stock during the shearing operation and for longitudinal feeding movement of the bar and the piece cut therefrom for discharge of the latter from the machine, and to protract said back gage member for engagement with the new end of the bar for cutting of the next piece therefrom, said back gage fluid motor having fluid communication with said low pressure-high volume pump via a directional control valve between said back gage fluid motor and said low pressure-high volume pump.

Claim 8

A hydraulic shearing machine comprising a fixed knife and a movable knife operative to engage opposite sides of longitudinally adjacent sections of a bar or the like to be sheared; a yieldable back support member opposite said movable knife operative to move with the latter during the shearing operation; a hold down member opposite said fixed knife operative to hold the bar in fixed position against said fixed knife during shearing movement of said movable knife; parallel connected fluid motors operative to move said movable knife and said hold down member toward and away from the bar; pump means and directional control valve means operatively connected to said fluid motors to actuate them by substantially equal fluid pressures to apply hold down force proportional to the shearing force as applied by said knife actuating motor; said pump means comprising a dual pump system including a low pressure-high volume pump, and a high pressure-low volume pump operatively connected to supply fluid under pressure to said directional control valve means, an unloading valve means to unload said low pressure-high volume pump in response to pressure rise at said directional control valve means to a predetermined value, and check valve means between said low pressure-high volume pump and said directional control valve means to permit flow of fluid from both of said pumps to said directional control valve for rapid advance and retraction of said movable knife and hold down member and to isolate said pumps from each other for high pressure actuation of said movable knife and said hold down member when they are engaged with the bar; said machine having a back gage member which is adapted to be engaged by the end of the bar to position it for cutting of a piece of predetermined length therefrom; and a fluid motor operatively connected with said back gage member to retract the latter for endwise movement of a cut piece of stock during the shearing operation and for longitudinal feeding movement of the bar and the piece cut therefrom for discharge of the latter from the machine, and to protract said back gage member for engagement with the new end of the bar for cutting of the next piece therefrom, said back gage fluid motor having fluid communication with said low pressure-high volume pump via a directional control valve between said back gage fluid motor and said low pressure-high volume pump.

Claim 9

A hydraulic shearing machine comprising a fixed knife and a movable knife operative to engage opposite sides of longitudinally adjacent sections of a bar or the like to be sheared; a yieldable back support member opposite said movable knife operative to move with the latter during the shearing operation; a hold down member opposite said fixed knife operative to hold the bar in fixed position against said fixed knife during shearing movement of said movable knife; parallel connected fluid motors operative to move said movable knife and said hold down member toward and away from the bar; pump means and directional control valve means operatively connected to said fluid motors to actuate them by substantially equal fluid pressures to apply hold down force proportional to the shearing force as applied by said knife actuating motor; said machine having a base plate, and a guide block on said base plate having an opening therethrough for passage of the bar and providing guideways for said movable knife and for said back support member, said fixed knife being secured to said block, said base plate also having thereon a fixed bar support adjacent to said block and said fixed knife, said base plate having thereon vertical guide means for said hold down member for reciprocation of the latter toward and away from a bar supported on said fixed knife and fixed support; said back support member comprising an elongated bar, the end portions of which are engaged in said guideways of said guide block; and a pair of fluid motors suspended beneath said base plate having piston rods extending through said base plate and engaged with said elongated bar, said back support actuating motors being in fluid communication with said pump means upstream of said directional control valve means whereby said back support actuating motors tend to constantly urge said back support member to a stop position substantially flush with said fixed knife thus to support the bar and to be yieldably moved upon engagement of said movable knife with the bar.

Claim 10

A hydraulic shearing machine comprising a fixed knife and a movable knife operative to engage opposite sides of longitudinally adjacent sections of a bar or the like to be sheared; a yieldable back support member opposite said movable knife operative to move with the latter during the shearing operation; a hold down member opposite said fixed knife operative to hold the bar in fixed position against said fixed knife during shearing movement of said movable knife; parallel connected fluid motors operative to move said movable knife and said hold down member toward and away from the bar; pump means and directional control valve means operatively connected to said fluid motors to actuate them by substantially equal fluid pressures to apply hold down force proportional to the shearing force as applied by said knife actuating motor; said machine having a base plate, and a guide block on said base plate having an opening therethrough for passage of the bar and providing guideways for said movable knife and for said back support member, said fixed knife being secured to said block, said base plate also having thereon a fixed bar support adjacent to said block and said fixed knife, said base plate having thereon vertical guide means for said hold down member for reciprocation of the latter toward and away from a bar supported on said fixed knife and fixed support; said back support member comprising an elongated bar, the end portions of which are engaged in said guideways of said guide block; and a pair of fluid motors suspended beneath said base plate having piston rods extending through said base plate and engaged with said elongated bar, said back support actuating motors being in fluid communication with said pump means upstream of said directional control valve means whereby said back support actuating motors tend to constantly urge said back support member to a stop position substantially flush with said fixed knife thus to support the bar and to be yieldably moved upon engagement of said movable knife with the bar.

Claim 11

The machine of claim 6 wherein the ends of said elongated bar are arcuate with a center struck from the middle of the bar to enable tilting of the bar in said guideways without binding; and wherein adjusting means are provided for vertical adjustment of said elongated bar to position said back support member substantially flush with said fixed knife.

Claim 12

A hydraulic shearing machine comprising a base structure having upper and lower heads secured to each other by tie rods; an upstanding guide block on said lower head having an opening therethrough for longitudinal feeding of a bar or the like to be sheared; a fixed knife in said block upon which the bar is adapted to be supported for shearing; a bar support means and a back support member on opposite sides of said fixed knife, said guide block having guideways supporting said back support member for vertical movement; a double acting fluid motor on said upper head having a vertically reciprocable knife assembly guided in said guide block for movement of a knife carried thereby into engagement with a bar supported by said fixed knife and said support means and yieldable back support member to shear the bar by displacement of the section of the bar beyond said fixed knife by movement of said movable knife and said back up member with respect to said fixed knife and bar support means; and a bar hold down assembly on said lower head including a vertically reciprocable hold down member above said support means and said fixed knife operative to hold the bar against said fixed knife and said support means during the shearing operation; and fluid motor operated wedge means to exert hold down force on said hold down member in proportion to the shearing force applied on said movable knife by said knIfe actuating motor; said yieldable back support member being actuated by a fluid motor connected to the same pressure source as is the knife actuating motor and said hold down actuating motor.

Claim 13

A hydraulic shearing machine comprising a base structure having upper and lower heads secured to each other by tie rods; an upstanding guide block on said lower head having an opening therethrough for longitudinal feeding of a bar or the like to be sheared; a fixed knife in said block upon which the bar is adapted to be supported for shearing; a bar support means and a back support member on opposite sides of said fixed knife, said guide block having guideways supporting said back support member for vertical movement; a double acting fluid motor on said upper head having a vertically reciprocable knife assembly guided in said guide block for movement of a knife carried thereby into engagement with a bar supported by said fixed knife and said support means and yieldable back support member to shear the bar by displacement of the section of the bar beyond said fixed knife by movement of said movable knife and said back up member with respect to said fixed knife and bar support means; and a bar hold down assembly on said lower head including a vertically reciprocable hold down member above said support means and said fixed knife operative to hold the bar against said fixed knife and said support means during the shearing operation; and fluid motor operated wedge means to exert hold down force on said hold down member in proportion to the shearing force applied on said movable knife by said knIfe actuating motor; said yieldable back support member being actuated by a fluid motor connected to the same pressure source as is the knife actuating motor and said hold down actuating motor.

Claim 14

A hydraulic shearing machine comprising a base structure having upper and lower heads secured to each other by tie rods; an upstanding guide block on said lower head having an opening therethrough for longitudinal feeding of a bar or the like to be sheared; a fixed knife in said block upon which the bar is adapted to be supported for shearing; a bar support means and a back support member on opposite sides of said fixed knife, said guide block having guideways supporting said back support member for vertical movement; a double acting fluid motor on said upper head having a vertically reciprocable knife assembly guided in said guide block for movement of a knife carried thereby into engagement with a bar supported by said fixed knife and said support means and yieldable back support member to shear the bar by displacement of the section of the bar beyond said fixed knife by movement of said movable knife and said back up member with respect to said fixed knife and bar support means; and a bar hold down assembly on said lower head including a vertically reciprocable hold down member above said support means and said fixed knife operative to hold the bar against said fixed knife and said support means during the shearing operation; and fluid motor operated wedge means to exert hold down force on said hold down member in proportion to the shearing force applied on said movable knife by said knife actuating motor; and hold down assembly comprising a pair of upstanding rods on said lower head which straddle said bar support means, and a wedge member vertically movably guided on said rods; said assembly having an upper head vertically adjustable on said rods; and a laterally disposed fluid motor on said head to laterally reciprocate said wedge member between said head and said hold down member; and spring means to raise said hold down member toward said head upon retraction of said wedge member by said fluid motor whereby the sheared bar may be longitudinally advanced for shearing of the next piece therefrom.

Claim 15

A hydraulic shearing machine comprising a base structure having upper and lower heads secured to each other by tie rods; an upstanding guide block on said lower head having an opening therethrough for longitudinal feeding of a bar or the like to be sheared; a fixed knife in said block upon which the bar is adapted to be supported for shearing; a bar support means and a back support member on opposite sides of said fixed knife, said guide block having guideways supporting said back support member for vertical movement; a double acting fluid motor on said upper head having a vertically reciprocable knife assembly guided in said guide block for movement of a knife carried thereby into engagement with a bar supported by said fixed knife and said support means and yieldable back support member to shear the bar by displacement of the section of the bar beyond said fixed knife by movement of said movable knife and said back up member with respect to said fixed knife and bar support means; and a bar hold down assembly on said lower head including a vertically reciprocable hold down member above said support means and said fixed knife operative to hold the bar against said fixed knife and said support means during the shearing operation; and fluid motor operated wedge means to exert hold down force on said hold down member in proportion to the shearing force applied on said movable knife by said knife actuating motor; and hold down assembly comprising a pair of upstanding rods on said lower head which straddle said bar support means, and a wedge member vertically movably guided on said rods; said assembly having an upper head vertically adjustable on said rods; and a laterally disposed fluid motor on said head to laterally reciprocate said wedge member between said head and said hold down member; and spring means to raise said hold down member toward said head upon retraction of said wedge member by said fluid motor whereby the sheared bar may be longitudinally advanced for shearing of the next piece therefrom.

Claim 16

The machine of claim 9 wherein said hold down assembly has rapid height adjustment means to accommodate large bar size variation.

Claim 17

A hydraulic shearing machine comprising a fixed knife and a movable knife operative to engage opposite sides of longitudinally adjacent sections of a bar or the like to be sheared; a yieldable back support member opposite said movable knife operative to move with the latter during the shearing operation; a hold down member opposite said fixed knife operative to hold the bar in fixed position against said fixed knife during shearing movement of said movable knife; parallel connected fluid motors operative to move said movable knife and said hold down member toward and away from the bar; pump means and directional control valve means operatively connected to said fluid motors to actuate them by substantially equal fluid pressures to apply hold down force proportional to the shearing force as applied by said knife actuating motor; said pump means comprising a dual pump system including a low pressure-high volume pump, and a high pressure-low volume pump operatively connected to supply fluid under pressure to said directional control valve means, an unloading valve means to unload said low pressure-high volume pump in response to pressure rise at said directional control valve means to a predetermined value, and check valve means between said low pressure-high volume pump and said directional control valve means to permit flow of fluid from both of said pumps to said directional control valve for rapid advance and retraction of said movable knife and hold down member and to isolate said pumps from each other for high pressure actuation of said movable knife and said hold down member when they are engaged with the bar; said machine havinG a back gage member which is adapted to be engaged by the end of the bar to position it for cutting of a piece of predetermined length therefrom; and a fluid motor operatively connected with said back gage member to retract the latter for endwise movement of a cut piece of stock during the shearing operation and for longitudinal feeding movement of the bar and the piece cut therefrom for discharge of the latter from the machine, and to protract said back gage member for engagement with the new end of the bar for cutting of the next piece therefrom, said back gage fluid motor having fluid communication with said high pressure-low volume pump via a directional control valve so that said back gage member resists with high force, the elongation of the piece being sheared especially when the latter is shorter than the bar size.

Claim 18

A hydraulic shearing machine comprising a fixed knife and a movable knife operative to engage opposite sides of longitudinally adjacent sections of a bar or the like to be sheared; a yieldable back support member opposite said movable knife operative to move with the latter during the shearing operation; a hold down member opposite said fixed knife operative to hold the bar in fixed position against said fixed knife during shearing movement of said movable knife; parallel connected fluid motors operative to move said movable knife and said hold down member toward and away from the bar; pump means and directional control valve means operatively connected to said fluid motors to actuate them by substantially equal fluid pressures to apply hold down force proportional to the shearing force as applied by said knife actuating motor; said pump means comprising a dual pump system including a low pressure-high volume pump, and a high pressure-low volume pump operatively connected to supply fluid under pressure to said directional control valve means, an unloading valve means to unload said low pressure-high volume pump in response to pressure rise at said directional control valve means to a predetermined value, and check valve means between said low pressure-high volume pump and said directional control valve means to permit flow of fluid from both of said pumps to said directional control valve for rapid advance and retraction of said movable knife and hold down member and to isolate said pumps from each other for high pressure actuation of said movable knife and said hold down member when they are engaged with the bar; said machine havinG a back gage member which is adapted to be engaged by the end of the bar to position it for cutting of a piece of predetermined length therefrom; and a fluid motor operatively connected with said back gage member to retract the latter for endwise movement of a cut piece of stock during the shearing operation and for longitudinal feeding movement of the bar and the piece cut therefrom for discharge of the latter from the machine, and to protract said back gage member for engagement with the new end of the bar for cutting of the next piece therefrom, said back gage fluid motor having fluid communication with said high pressure-low volume pump via a directional control valve so that said back gage member resists with high force, the elongation of the piece being sheared especially when the latter is shorter than the bar size.

Claim 19

A hydraulic shear having a movable shear blade, a hold down clamp and a yieldable backup support, a hydraulic power cylinder for moving said shear blade, a hydraulic hold down clamp cylinder for operating said hold down clamp, a hydraulic backup support cylinder for operating said backup support, all of said cylinders being connected for operation by a common pressure source, whereby the force applied to said shear blade is proportional to the forces applied to said hold down clamp and to said backup support; said common pressure source including a low pressure-high volume pump and a high pressure-low volume pump, and directional control valve means downstream of the connection of said pressure source to said backup support cylinder for communicating the discharge sides of said pumps with said power and hold down clamp cylinders for rapid cycling operation of said shear blade by the conjoint discharge of said pumps during movement of said shear blade toward a bar to be sheared thereby and away from a piece of such bar sheared thereby; said pumps having means associated therewith to conduct the discharge of said high pressure-low volume pump only to all of said cylinders during shearing engagement of said shear blade with such bar.

Claim 20

A hydraulic shear having a movable shear blade, a hold down clamp and a yieldable backup support, a hydraulic power cylinder for moving said shear blade, a hydraulic hold down clamp cylinder for operating said hold down clamp, a hydraulic backup support cylinder for operating said backup support, all of said cylinders being connected for operation by a common pressure source, whereby the force applied to said shear blade is proportional to the forces applied to said hold down clamp and to said backup support; said common pressure source including a low pressure-high volume pump and a high pressure-low volume pump, and directional control valve means downstream of the connection of said pressure source to said backup support cylinder for communicating the discharge sides of said pumps with said power and hold down clamp cylinders for rapid cycling operation of said shear blade by the conjoint discharge of said pumps during movement of said shear blade toward a bar to be sheared thereby and away from a piece of such bar sheared thereby; said pumps having means associated therewith to conduct the discharge of said high pressure-low volume pump only to all of said cylinders during shearing engagement of said shear blade with such bar.