Continuously operated vacuum furnace having work part transfer conveyor and load and unload mechanism

Claim 2

A conveyor furnace for continuously introducing and processing work parts therein without breaking the vacuum within the furnace, comprising a housing having a heating chamber located therein in which the work parts are heat treated, a cooling chamber in said housing communicating with said heating chamber and receiving work parts therefrom after the heat treatment of said work parts, said heating and cooling chambers being normally maintained at a subatmospheric pressure, a conveyor belt extending through said heating and cooling chambers in said housing for continuously transferring work parts therethrough during the heat treatment of said work parts, a loading station located at the forward end of said housing for communication with said heating chamber and including isolating means that defines a confined chamber at said loading station, a discharge station located at the rearmost end of saiD housing for communication with said cooling chamber and including isolating means that defines a confined chamber at said discharge station, first conveying means located in the confined chamber at said loading station for transferring work parts introduced therein toward said heating chamber, second conveying means located exteriorly of said confined chamber and forwardly of said heating chamber for receiving the work parts from said first conveying means and transferring them to said conveyor belt, and means for controlling movement of the first and second conveying means at said loading station and in timed sequence with the operation of the isolating means at said loading station so that the work parts are sequentially transferred therefrom to said conveyor belt in the heating chamber, wherein the subatmospheric pressure in said heating and cooling chambers is effectively maintained during loading of the work parts into the furnace.

Claim 3

A conveyor furnace as set forth in claim 1, a first conveyor located at said discharge station forwardly of the confined chamber thereat and communicating with said cooling chamber, a second conveyor located within the confined chamber at said discharge station, and means for controlling said first and second conveyors and in timed sequence with the operation of the isolating means at said discharge station so that the work parts are sequentially transferred from the conveyor belt at said cooling station onto said first conveyor and then onto said second conveyor, wherein the subatmospheric pressure in said heating and cooling chambers is effectively maintained during discharge of the work parts from said furnace.

Claim 4

A conveyor vacuum furnace for continuously introducing and processing work parts therein without breaking the vacuum within the furnace, comprising a housing having a heating chamber formed therein in which the work parts are heat treated, a cooling chamber in said housing communicating with said heating chamber and receiving work parts therefrom after the heat treatment of said work parts, said heating and cooling chambers being normally maintained at a subatmospheric pressure, a conveyor belt extending through said heating and cooling chambers in said housing for continuously transferring work parts therethrough for the heat treatment of said work parts, a loading station located at the forward end of said housing for communication with said heating chamber, a discharge station located at the rearmost end of said housing for communication with said cooling chamber, means for selectively isolating said loading station and discharge station from said heating chamber and cooling chamber, respectively, wherein the subatmospheric pressure in said heating and cooling chambers is effectively maintained during loading of the work parts into the furnace, processing of work parts through said heating and cooling chambers and discharge of the heat treated work parts from the furnace, the isolating means at said loading station including inner and outer spaced door assemblies between which a confined chamber at the loading station is defined, operating means individually interconnected to said spaced door assemblies for independently moving said door assemblies to and from the open and sealed positions thereof, the confined chamber at the loading station being evacuated while said door assemblies are sealed and the work parts are disposed therein, whereafter the inner door assembly is opened and said work parts are transferred to said heating chamber, the isolating means at said discharge station including inner and outer spaced door assemblies between which a confined chamber at the discharge station is defined, operating means individually interconnected to said spaced door assemblies at the discharge station for independently moving the door assemblies to and from the open and sealed positions thereof, means for introducing an atmosphere into the confined chamber at the discharge station while the door assemblies thereAt are sealed, whereafter the outer door assembly at said discharge station is opened for removal of the heat treated work parts therefrom, first conveying means located in the confined chamber at said loading station for transferring work parts introduced therein interiorly of the inner door, second conveying means located interiorly of the inner door at the loading station for moving the work parts onto said conveyor, and means for controlling the movement of the first and second conveying means at said loading station so that work parts are automatically transferred to said conveyor belt after the vacuum in the confined chamber at the loading station is equalized with that in said heating chamber.

Claim 5

A conveyor vacuum furnace for continuously introducing and processing work parts therein without breaking the vacuum within the furnace, comprising a housing having a heating chamber formed therein in which the work parts are heat treated, a cooling chamber in said housing communicating with said heating chamber and receiving work parts therefrom after the heat treatment of said work parts, said heating and cooling chambers being normally maintained at a subatmospheric pressure, a conveyor belt extending through said heating and cooling chambers in said housing for continuously transferring work parts therethrough for the heat treatment of said work parts, a loading station located at the forward end of said housing for communication with said heating chamber, a discharge station located at the rearmost end of said housing for communication with said cooling chamber, means for selectively isolating said loading station and discharge station from said heating chamber and cooling chamber, respectively, wherein the subatmospheric pressure in said heating and cooling chambers is effectively maintained during loading of the work parts into the furnace, processing of work parts through said heating and cooling chambers and discharge of the heat treated work parts from the furnace, the isolating means at said loading station including inner and outer spaced door assemblies between which a confined chamber at the loading station is defined, operating means individually interconnected to said spaced door assemblies for independently moving said door assemblies to and from the open and sealed positions thereof, the confined chamber at the loading station being evacuated while said door assemblies are sealed and the work parts are disposed therein, whereafter the inner door assembly is opened and said work parts are transferred to said heating chamber, the isolating means at said discharge station including inner and outer spaced door assemblies between which a confined chamber at the discharge station is defined, operating means individually interconnected to said spaced door assemblies at the discharge station for independently moving the door assemblies to and from the open and sealed positions thereof, means for introducing an atmosphere into the confined chamber at the discharge station while the door assemblies thereAt are sealed, whereafter the outer door assembly at said discharge station is opened for removal of the heat treated work parts therefrom, first conveying means located in the confined chamber at said loading station for transferring work parts introduced therein interiorly of the inner door, second conveying means located interiorly of the inner door at the loading station for moving the work parts onto said conveyor, and means for controlling the movement of the first and second conveying means at said loading station so that work parts are automatically transferred to said conveyor belt after the vacuum in the confined chamber at the loading station is equalized with that in said heating chamber.

Claim 6

A conveyor vacuum furnace as set forth in claim 3, said moving means for each door assembly including a rotatable crank assembly interconnected thereto for moving the door assembly in an axial direction with respect to the longitudinal axis of the furnace, wherein the door assembly is movable between a sealed and unsealed position.

Claim 7

A conveyor vacuum furnace as set forth in claim 4, each of said door assemblies including a frame that is pivotally mounted at the uppermost end thereof, said crank assembly for each door assembly including a crank arm connected to the lower end of said frame and a rod element joined to said crank arm, and power means for rotating said rod element at required intervals to rotate said crank arm, wherein the frame is pivotally moved to move its door assembly to and from a sealed and unsealed position.

Claim 8

A conveyor vacuum furnace as set forth in claim 5, each door assembly including a door member that is mounted for sliding vertical movement in the frame thereof, a rod member interconnected to the door member of each door assembly at the uppermost end thereof, and power means interconnected to each rod member and being operable at required intervals to elevate the door in its frame to an open position after the unsealing of its door assembly and for lowering the door in its frame for pivotal movement with the frame to the sealed position thereof.

Claim 9

A conveyor vacuum furnace as set forth in claim 3, said first and second conveying means including a plurality of rollers that are drivingly interconnected, and drive means for said first and second conveying means including a motor to which drive members of the first and second conveying means are interconnected, said drive members of each conveying means being drivingly interconnected to the rollers thereof.

Claim 10

A conveyor vacuum furnace for continuously introducing and processing work parts therein without breaking the vacuum within the furnace, comprising a housing having a heating chamber formed therein in which the work parts are heat treated, a cooling chamber in said housing communicating with said heating chamber and receiving work parts therefrom after the heat treatment of said work parts, said heating and cooling chambers being normally maintained at a subatmospheric pressure, a conveyor belt extending through said heating and cooling chambers in said housing for continuously transferring work parts therethrough for the heat treatment of said work parts, a loading station located at the forward end of said housing for communication with said heating chamber, a discharge station located at the rearmost end of said housing for communication with said cooling chamber, means for selectively isolating said loading station and discharge station from said heating chamber and cooling chamber, respectively, wherein the subatmospheric pressure in said heating and cooling chambers is effectively maintained during loading of the work parts into the furnace, processing of work parts through said heating and cooling chambers and discharge of the heat treated work parts from the furnace, an adapter section being located intermediate the cooling section and heating chamber and providing communication therebetween, a series of rollers being located in said adapter section and receiving The conveyor belt thereon, said rollers being mounted in an inclined frame in series relation and providing for a change of plane of travel of said conveyor belt as it returns from the cooling chamber to the heating chamber.

Claim 11

A conveyor vacuum furnace for continuously introducing and processing work parts therein without breaking the vacuum within the furnace, comprising a housing having a heating chamber formed therein in which the work parts are heat treated, a cooling chamber in said housing communicating with said heating chamber and receiving work parts therefrom after the heat treatment of said work parts, said heating and cooling chambers being normally maintained at a subatmospheric pressure, a conveyor belt extending through said heating and cooling chambers in said housing for continuously transferring work parts therethrough for the heat treatment of said work parts, a loading station located at the forward end of said housing for communication with said heating chamber, a discharge station located at the rearmost end of said housing for communication with said cooling chamber, means for selectively isolating said loading station and discharge station from said heating chamber and cooling chamber, respectively, wherein the subatmospheric pressure in said heating and cooling chambers is effectively maintained during loading of the work parts into the furnace, processing of work parts through said heating and cooling chambers and discharge of the heat treated work parts from the furnace, an adapter section being located intermediate the cooling section and heating chamber and providing communication therebetween, a series of rollers being located in said adapter section and receiving The conveyor belt thereon, said rollers being mounted in an inclined frame in series relation and providing for a change of plane of travel of said conveyor belt as it returns from the cooling chamber to the heating chamber.

Claim 12

A conveyor vacuum furnace for continuously introducing and processing work parts therein without breaking the vacuum within the furnace, comprising a housing having a heating chamber formed therein in which the work parts are heat treated, a cooling chamber in said housing communicating with said heating chamber and receiving work parts therefrom after the heat treatment of said work parts, said heating and cooling chambers being normally maintained at a subatmospheric pressure, a conveyor belt extending through said heating and cooling chambers in said housing for continuously transferring work parts therethrough for the heat treatment of said work parts, a loading station located at the forward end of said housing for communication with said heating chamber, a discharge station located at the rearmost end of said housing for communication with said cooling chamber, means for selectively isolating said loading station and discharge station from said heating chamber and cooling chamber, respectively, wherein the subatmospheric pressure in said heating and cooling chambers is effectively maintained during loading of the work parts into the furnace, processing of work parts through said heating and cooling chambers and discharge of the heat treated work parts from the furnace, said cooling section including a plurality of transverse metallic segments that are disposed in side-by-side relation and define a support surface over which the conveyor belt travels, and a plurality of horizontally disposed cooling tubes located beneath said segments and defining a support therefor, a coolant material being circulated through said cooling tubes, wherein heat from the work parts is removed therefrom as they are conveyed through the cooling chamber.

Claim 13

A conveyor vacuum furnace for continuously introducing and processing work parts therein without breaking the vacuum within the furnace, comprising a housing having a heating chamber formed therein in which the work parts are heat treated, a cooling chamber in said housing communicating with said heating chamber and receiving work parts therefrom after the heat treatment of said work parts, said heating and cooling chambers being normally maintained at a subatmospheric pressure, a conveyor belt extending through said heating and cooling chambers in said housing for continuously transferring work parts therethrough for the heat treatment of said work parts, a loading station located at the forward end of said housing for communication with said heating chamber, a discharge station located at the rearmost end of said housing for communication with said cooling chamber, means for selectively isolating said loading station and discharge station from said heating chamber and cooling chamber, respectively, wherein the subatmospheric pressure in said heating and cooling chambers is effectively maintained during loading of the work parts into the furnace, processing of work parts through said heating and cooling chambers and discharge of the heat treated work parts from the furnace, said cooling section including a plurality of transverse metallic segments that are disposed in side-by-side relation and define a support surface over which the conveyor belt travels, and a plurality of horizontally disposed cooling tubes located beneath said segments and defining a support therefor, a coolant material being circulated through said cooling tubes, wherein heat from the work parts is removed therefrom as they are conveyed through the cooling chamber.

Claim 14

A conveyor vacuum conveyor furnace as set forth in claim 9, a heat exchanger located exteriorly of said housing and communicating with said cooling tubes wherein the coolant material is directed to said heat exchanger from said cooling tubes and after regeneration is thereafter returned to said cooling tubes for withdrawing the heat from the work parts conveyed through said cooling chamber.

Claim 15

A conveyor vacuum furnace for continuously introducing and processing work parts therein without breaking the vacuum within the furnace, comprising a housing having a heating chamber formed therein in which the work parts are heat treated, a cooling chamber in said housing communicating with said heating chamber and receiving work parts therefrom after the heat treatment of said work parts, said heating and cooling chambers being normally maintained at a subatmospheric pressure, a conveyor belt extending through said heating and cooling chambers in said housing for continuously transferring work parts therethrough for the heat treatment of said work parts, a loading station located at the forward end of said housing for communication with said heating chamber, a discharge station located at the rearmost end of said housing for communication with said cooling chamber, means for selectively isolating said loading station and discharge station from said heating chamber and cooling chamber, respectively, wherein the subatmospheric pressure in said heating and cooling chambers is effectively maintained during loading of the work parts into the furnace, processing of work parts through said heating and cooling chambers and discharge of the heat treated work parts from the furnace, the isolating means at said loading and discharge stations, each including a chamber, a first door assembly located at one end of said chamber and comprising a pivotally mounted frame, and a second door assembly located at the other end of said chamber and comprising a pivotally mounted frame and a door member mounted for vertical movement thereIn, said door assemblies at each station defining a confined chamber therebetween when said door members are in the sealed position thereof.

Claim 16

A conveyor vacuum furnace for continuously introducing and processing work parts therein without breaking the vacuum within the furnace, comprising a housing having a heating chamber formed therein in which the work parts are heat treated, a cooling chamber in said housing communicating with said heating chamber and receiving work parts therefrom after the heat treatment of said work parts, said heating and cooling chambers being normally maintained at a subatmospheric pressure, a conveyor belt extending through said heating and cooling chambers in said housing for continuously transferring work parts therethrough for the heat treatment of said work parts, a loading station located at the forward end of said housing for communication with said heating chamber, a discharge station located at the rearmost end of said housing for communication with said cooling chamber, means for selectively isolating said loading station and discharge station from said heating chamber and cooling chamber, respectively, wherein the subatmospheric pressure in said heating and cooling chambers is effectively maintained during loading of the work parts into the furnace, processing of work parts through said heating and cooling chambers and discharge of the heat treated work parts from the furnace, the isolating means at said loading and discharge stations, each including a chamber, a first door assembly located at one end of said chamber and comprising a pivotally mounted frame, and a second door assembly located at the other end of said chamber and comprising a pivotally mounted frame and a door member mounted for vertical movement thereIn, said door assemblies at each station defining a confined chamber therebetween when said door members are in the sealed position thereof.

Claim 17

A conveyor vecuum furnace as set forth in claim 11, means for evacuating the confined chamber between the door assemblies when both door assemblies are in the sealed position thereof and after loading of the work parts in said confined chamber, whereafter and when the subatmospheric pressure in said heating chamber is equalized with that in the confined chamber at the loading station, the door assembly adjacent to said heating chamber is opened to provide for movement of said work parts into the heating chamber.

Claim 18

A conveyor vacuum furnace as set forth in claim 11, the isolating means at said loading station further including control means interconnected to the door assemblies for selectively moving the door assemblies at the loading station to and from a sealed position, wherein one of said door assemblies is sealed to seal the heating chamber when the other door assembly is unsealed during a work parts loading operation.

Claim 19

A conveyor vacuum furnace as set forth in claim 13, each of said door assemblies including a frame in which a door member is slidably mounted, and means interconnected to each door member for vertically moving the door members to and from and the open and closed positions thereof.

Claim 20

A conveyor vacuum furnace as set forth in claim 14, each of said frames being pivotally mounted at the upper end thereof, having side tracks for receiving a door member in vertical sliding relation therein.