Title: Electric welder
Abstract: A welder comprises a source of electrical welding current. A housing houses the source and has front and rear walls and a top wall. A control device, for controlling a condition of the welder, is located along the top wall. A rear wheel is attached to the housing and has a portion located both rearward and downward from the housing. This enables the welder to pivot about the rear wheel between an upright position and a lying position. A front wheel and a foot are attached to the housing. In the upright position, the front and rear wheels engage the floor to support the housing above and spaced from the floor. In the lying position, the rear wheel and the foot engage the floor to support the housing above and spaced from the floor.
Patent Number: 6,897,406 Issued on 05/24/2005 to Crisler, III, et al.
| Inventors:
|
Crisler, III; Howard E. (Antioch, TN);
DeYoung; Roger L. (Franklin, TN);
Moore; David J. (Mt. Juliet, TN);
Nutter; James A. (Lebanon, TN);
Rivera; Matthew L. (Mableton, GA)
|
| Assignee:
|
Campbell Hausfeld/Scott Fetzer (Harrison, OH)
|
| Appl. No.:
|
394691 |
| Filed:
|
March 21, 2003 |
| Current U.S. Class: |
219/130.1; 219/136 |
| Intern'l Class: |
B23K 009/10 |
| Field of Search: |
219/8621,116,130.1,136
|
References Cited [Referenced By]
U.S. Patent Documents
| 2157871 | May., 1939 | Steinert.
| |
| 2253403 | Aug., 1941 | Steinert.
| |
| D161912 | Feb., 1951 | Fotie.
| |
| 2866076 | Dec., 1958 | Aversten.
| |
| 2883498 | Apr., 1959 | Crep.
| |
| 3227979 | Jan., 1966 | Kamp.
| |
| 3492455 | Jan., 1970 | Brundage.
| |
| 3510623 | May., 1970 | Wolgast.
| |
| 3523272 | Aug., 1970 | Jost et al.
| |
| 4107635 | Aug., 1978 | Brundage et al.
| |
| 4443187 | Apr., 1984 | Shaftner et al.
| |
| D275293 | Aug., 1984 | Bouman.
| |
| D280329 | Aug., 1985 | Bouman.
| |
| 4804811 | Feb., 1989 | Raycher et al.
| |
| 5452908 | Sep., 1995 | Bencic.
| |
| 6051806 | Apr., 2000 | Shikata et al.
| |
| 6170839 | Jan., 2001 | Kizewski.
| |
| 6396019 | May., 2002 | Williams.
| |
| 6596972 | Jul., 2003 | Di Novo et al.
| |
Primary Examiner: Shaw; Clifford C.
Attorney, Agent or Firm: Jones Day
Claims
1. A welder comprising:
a source of electrical welding current;
a housing that houses the source and has front and rear walls and top and bottom
walls;
rear wheels attached to the housing for wheeling the housing about a floor and
for pivoting the housing rearwardly about the rear wheels from an upright position
to a lying position;
a handle structure extending upward from the rear wall; and
a foot attached to the rear wall and configured, in the lying position of the
housing, to engage the floor and space the handle structure above the floor.
2. The welder of claim 1 wherein the rear wall is vertical when the welder is
in the upright position and horizontal when the welder is in the lying position.
3. The welder of claim 1 wherein the handle structure and the foot are parts
of a single bent bar.
4. The welder of claim 1 wherein the foot includes a bar extending rearward and
downward from the rear wail, such that a cable can be wrapped and lodged from above
between the rear wall and the handle structure and from below between the rear
wall and the foot.
5. The welder of claim 1 wherein the foot extends rearward and upward from the
rear wall to function as a hook for hanging a welding accessory.
6. The welder of claim 1 wherein the handle structure includes first and second
side bars extending upward from the rear wall.
7. The welder of claim 6 wherein the side bars are vertical.
8. The welder of claim 1 wherein the handle structure includes a horizontal bar
located above and parallel with the rear wall.
9. The welder of claim 1 wherein the top wall is inclined, extending rearward
and upward from the front wall.
10. The welder of claim 1 further comprising, at the top wall, control devices
for controlling conditions of the welder.
11. The welder of claim 1 wherein the housing has two compartments for storing
accessories, configured such that, in both the upright and lying positions of the
welder, an opening of one of the compartments faces upward arid an opening of the
other of the compartments faces horizontally.
12. A welder comprising:
a source of electrical welding current;
a housing that houses the source and has front and rear walls and top and bottom
walls;
rear wheels attached to the housing for wheeling the housing about a floor; and
a handle structure configured to be grasped by hand to wheel the housing about
the floor, including first and second side bars extending upward from the rear
wall; and
an accessory hook located between the side bars, extending rearward and upward
from the rear wall and configured for hanging a welding accessory.
13. The welder of claim 12 wherein the hook has a top end that is rearward from
and lower than a top end of the handle structure.
14. The welder of claim 12 wherein the housing can pivot rearwardly about the
rear wheels from an upright position to a lying position, and the handle structure
can be grasped by hand to pivot the welder into and out of the lying position.
15. The welder of claim 14 wherein, in the lying position of the housing, the
hook engages the floor and spaces the side bars above the floor.
16. The welder of claim 14 wherein the side bars are vertical in the upright
position of the housing and horizontal and spaced from the floor in the lying position
of the housing.
17. The welder of claim 14 wherein the handle structure includes a horizontal
bridging bar extending from a top end of the first side bar to a top end of the
second side bar and is spaced above the floor when the housing is in the lying position.
18. A welder comprising:
a source of electrical welding current;
a housing that houses the source and has front and rear walls and top and bottom
walls;
rear wheels attached to the housing for wheeling the housing about a floor; and
a handle structure configured to be grasped by hand to wheel the housing about
the floor, including first and second side bars extending upward from the rear
wall; and
first and second turned-out bars located respectively directly below the side
bars and extending rearward and downward from the rear wall such that a welding
cable can be wrapped and lodged from above between the rear wall and the side bars
and from below between the rear wall and the turned-out bars.
19. The welder of claim 18 wherein the housing can pivot rearwardly about the
rear wheels from an upright position to a lying position, and the handle structure
can be grasped by hand to pivot the welder into and out of the lying position.
20. The welder of claim 19 wherein, in the lying position of the housing, the
turned-out sections engage the floor and space the side bars above the floor.
21. The welder of claim 19 wherein the side bars are vertical in the upright
position of the housing and horizontal and spaced from the floor in the lying position
of the housing.
22. The welder of claim 19 wherein the side bars and turned-out bars are sections
of a single bent bar.
23. The welder of claim 19 further comprising a horizontal bridging bar extending
from a top end of the first side bar to a top end of the second side bar, that
is spaced above the floor when the housing is in the lying position.
24. A welder comprising:
a source of electrical welding current;
a housing that houses the source and has front and rear walls and top and bottom
walls;
a control device at the top wall for selecting a welding current;
a display device at the top wall for displaying the welding current; and
a storage compartment extending downward from an opening in the top wall, rearward
of the control and display devices.
Description
TECHNICAL FIELD
The present invention relates to electric welders.
BACKGROUND
A welder is used to weld a metal work piece. The welder produces an electrical
welding current. The welding current is conducted to the work piece by a first
cable and to a welding rod by a second cable. The current flows through the work
piece and the rod when they contact each other. The work piece and the rod are
thus heated and melted together.
SUMMARY
A welder embodying the present invention comprises a source of electrical welding
current. A housing houses the source and has front and rear walls and a top wall.
A control device, for controlling a condition of the welder, is located along the
top wall. A rear wheel is attached to the housing and has a portion located both
rearward and downward from the housing. This enables the welder to pivot about
the rear wheel between an upright position and a lying position. A front wheel
and a foot are attached to the housing. In the upright position, the front and
rear wheels engage the floor to support the housing above and spaced from the floor.
In the lying position, the rear wheel and the foot engage the floor to support
the housing above and spaced from the floor.
Preferably, a handle attached to said housing is spaced from the floor
in both the upright and lying positions. The handle and the foot are parts of a
single bent bar. The top wall is inclined, extending rearward and upward with reference
to the upright position of the welder.
In accordance with another aspect of the invention, the top wall is inclined.
Located along the top wall are a device for selecting a nominal value of the welding
current, a device for displaying the nominal value of the welding current, a switch
for turning on the welder, a device for indicating when the welder is turned on,
and a thermal overload indicator light.
Preferably, the welder further comprises a compartment for storing welding
accessories, extending downward from an opening in said top wall.
In another aspect of the invention, a wheel is attached to the housing. The wheel
is configured for wheeling the housing about a floor and also for pivoting the
welder about the wheel between the upright position and the lying position. The
welder has two compartments for storing welding accessories, configured such that,
in either of the upright and lying positions of the welder, an opening of one of
the compartments faces upward and an opening of the other of the compartments faces horizontally.
In another aspect, the housing has a front wall and an inclined top wall extending
rearward and upward from the front wall. A compartment extends rearward from the
front wall.
In yet another aspect, a support structure is attached to the housing. The support
structure is configured to serve as a hook for hanging an accessory in the upright
position of the welder and also as a foot for supporting the housing above the
floor in the lying position of the welder.
In another embodiment of the invention, an apparatus comprises a transformer
for
producing an electrical current. The transformer comprises primary and secondary
windings wound about a core. A shunt is configured to control the current by movement
of the shunt along an axis into and out of the core within a predetermined full
range of travel. A control device is configured to be rotated by an operator about
the axis for controlling the current. A mechanical linkage is connected between
the shunt and the control device. The linkage is configured to effect the movement
of the shunt by rotation of the device such that the predetermined full range of
travel of the shunt corresponds to multiple revolutions of the device.
According to another aspect of the invention, a shunt is for selecting
a nominal value of the current by movement of the shunt along an axis into and
out of the core. The apparatus further comprises a hand-movable control device.
A first mechanical linkage connects the control device to the shunt such that a
movement of the control device causes the movement of the shunt, whereby the nominal
value of the current can be selected by the movement of the control device. The
apparatus further comprises a rotatable pointer. A second mechanical linkage connects
the pointer to the shunt such that the movement of the shunt causes a rotation
of the pointer such that the nominal value is indicated by an angular position
of the pointer. The first linkage is different from the second linkage.
In another aspect, the apparatus comprises a gage and a helical band extending
axially from the gage. A bracket is connected to the shunt, and has a slit that
receives the helical band closely and slidingly such that the axial movement of
the shunt causes a corresponding rotation of the band.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1A is a front perspective view of a welder embodying the present invention,
shown in an upright position;
FIG. 1B is a view similar to FIG. 1A, in which certain walls of the welder are
rendered transparent in order to show internal parts of the welder;
FIG. 2A is a side view of the welder in the upright position;
FIG. 2B is a side view of the welder in a lying position;
FIG. 3 is a rear perspective view of the welder in the upright position, illustrating
a first use of the welder;
FIG. 4 is a partial side view of the welder in the lying position, illustrating
the first use of the welder;
FIG. 5 is a rear perspective view of the welder in the upright position, illustrating
a second use of the welder;
FIG. 6 is a view similar to FIG. 1A, illustrating other uses of the welder;
FIG. 7 is a head-on view of a top wall of the welder;
FIG. 8 is a side sectional view of the welder;
FIG. 9A is a perspective view of parts shown in FIG. 8;
FIG. 9B is a partially-exploded view of the parts shown in FIG. 9A; and
FIG. 10 is a more fully exploded view of parts shown in FIG. 9B.
DESCRIPTION
The apparatus
10 shown in FIG. 1A has parts which, as described below,
are examples of the elements recited in the claims. The apparatus
10 is
a welder. The welder
10 is described as follows with reference to an upright
position of the welder
10 shown in FIG.
1A.
As shown in FIG. 1B, the welder
10 has a source
14 of electrical
welding current contained within a housing
20. The housing
20 has
front and rear walls
22 and
24, two opposite side walls
26
and
28, a bottom wall
30 and an inclined top wall
40. Two
cables
42 extend outward from the housing
20 to conduct the welding
current from the source
14 to a welding rod
46 and a work piece
48
for welding the work piece
48. First and second control devices
50
and
52 are located along the top wall
40. The control devices
50
and
52 are accessible and viewable by an operator and used by the operator
to manually control operating conditions of the welder
10. First, second
and third display devices
60,
62 and
64 are also located along
the top wall
40. They are viewable by the operator and display operating
conditions of the welder
10. Two rear wheels
66 and
68 (FIG.
3), for wheeling the welder
10 about a floor
70, are attached
to the housing
20.
The source
14 of the welding current in this example is a transformer.
The transformer
14 comprises primary windings
72 and secondary windings
74 wound about a steel core
76. The primary windings
72 are
powered by an electrical input current provided by a power cord
78 plugged
into a wall socket
80. The secondary windings
74 output the welding
current through two output lines
82 to two jacks
84. The two jacks
84 extend through holes in the top wall
40 of the housing
20.
Each welding cable
42 is connected at one end to a clamp
90 that
can be clamped to the welding rod
46 or the work piece
48. The welding
cable
42 is connected at the opposite end to a plug
92 that can be
plugged into a respective jack
84.
The rear wheels
66 and
68 rotate about respective shafts
100,
as shown in FIG.
2A. Each shaft
100 projects outwardly from, and
perpendicular to, a respective one of the side walls
26 and
28. The
wheels
66 and
68 are configured, in terms of size and location, such
that a portion
102 of each wheel is located both rearward and downward from
the housing
20.
Two front wheels
110 and
112 (FIG. 1B) are attached to the bottom
wall
30 forward from the two rear wheels
66 and
68. In the
example, the front wheels
100 and
112 are castors and thus swivelable.
The front and rear wheels
66,
68,
110 and
112 together
enable the operator to push, pull and maneuver the welder
10 about the floor
70.
The welder
10 can pivot about the wheel axles
100, and thus about
the rear wheels
66 and
68, as indicated by an arrow
115, from
the upright position shown in FIG. 2A to a lying position shown in FIG.
2B.
The rear wall
24 is visually vertical when the welder
10 is in the
upright position (FIG.
2A), and visually horizontal when the welder
10
is in the lying position (FIG.
2B). Herein, "visually" means as appearing
to the casual observer, "vertical" means perpendicular to the floor, and "horizontal"
means parallel with the floor. The welder
10 preferably rotates about 90
degrees when being pivoted from the upright position to the lying position.
The top wall
40 is inclined whether the welder
10 is in the upright
position or the lying position. Specifically, when the welder
10 is in the
upright position (FIG.
2A), the top wall
40 extends rearward and
upward, at about a 30 degree angle from horizontal, from the front wall
22.
The top wall
40 thus faces the operator's eyes when the operator stands
in front of the welder
10. This directs the control and display devices
50,
52,
60,
62 and
64 (FIG. 1A) toward the operator's
eyes. This facilitates grasping the control devices
50 and
52 and
viewing the display devices
60 and
62. When the welder
10
is in the lying position (FIG.
2B), the top wall
40 is inclined such
that the top wall
40 faces the operator's eyes as the operator is kneeling
or lying.
A multifunctional support
120, shown in FIG. 3, is attached to the rear
wall
24. As described with reference to the upright position of the welder
10 shown in FIG. 3, the support
120 comprises a horizontally-extending
bridging bar
122. From opposite ends of the bridging bar
122, two
side bars
124 extend downward. From bent bottom ends
126 of the side
bars
124, two turned-out bars
128 extend downward and rearward to
a distal end
130 of the support
120. An upper portion
132
of each side bar
124 extends vertically above the rear wall
24. A
lower portion
134 of each side bar extends alongside, and affixed to, the
rear wall
24. The support
120 serves several functions, described
as follows.
The bridging bar
122 serves as a handle. It can be grasped by hand to
wheel the welder
10 about the floor
70 and to pivot the welder
10
about the rear wheels
66 and
68 between the upright and lying positions
(FIGS.
2A and
2B).
The side bars
122 and the turned-out bars
128 together serve as
a bracket for wrapping the welding cables
42 and the power cord
78
for storage. As shown in FIG. 3, the cables
42 and the cord
78 are
wrapped such that they are lodged from above between the top of the rear wall
24
and the side bars
124. The cables
42 and the cord
78 are lodged
from below between the rear wall
24 and the turned-out bars
128.
When the cables
42 and the cord
78 are wrapped sufficiently tightly
in this fashion, they will remain securely in place even when the welder
10
is in the lying position as shown in FIG.
4. In this position, the cables
42 and the cord
78 will be retained above the floor
70 by
the side bars
124 and the turned-out bars
128.
The turned-out bars
128 also serve as feet for the welder
10 when
the welder
10 is in the lying position as shown in FIGS. 2B and 4. The turned-out
bars
128 are configured, together with the rear wheels
66 and
68,
to support the rear wall
24 and the bridging bar
122 above the floor
70 when the welder
10 is in the lying position. This protects the
rear wall
24 from damage by debris on the floor
70 and facilitates
grasping of the bridging bar
122 to pivot the welder
10 upward. At
the location on each turned-out bar where it contacts the floor
70, the
turned-out bar
128 includes a material, such as plastic, that avoids scratching
of the floor
70. Additionally, the turned-out bars
128 are configured,
relative to the rear wheels
66 and
68, to orient the rear wall
24
and the side bars
124 parallel with the floor
70 when the welder
10 is in the lying position.
An L-shaped hook
140, shown in FIG. 3, is attached to the rear wall
24
at the top of the rear wall
24. With reference to the upright position of
the welder
10, the hook
140 comprises a horizontal leg
142
extending from the rear wall
24 rearward and a vertical leg
144 extending
from the horizontal leg
142 upward. As shown in FIG. 5, the hook
140
can be used to hang a welding accessory, such as a helmet
146, when the
welder
10 is in the upright position. As shown in FIGS. 2B and 4, the hook
140 can also serve as a foot when the welder
10 is in the lying position.
Like the turned-out bar
128, the hook
140 is configured relative
to the rear wheels
66 and
68 to support the rear wall
24 and
the bridging bar
122 above, and spaced from, the floor
70 when the
welder
10 is in the lying position. As explained above, this protects the
rear wall
24 from damage and facilitates grasping of the bridging bar
122.
The hook
140 is further configured relative to the rear wheels
66
and
68 to orient the rear wall
24 and the side bars
124 parallel
with the floor
70. Where the hook
140 contacts the floor
70,
the hook
140 includes a material that avoids scratching of the floor
70,
such as plastic.
The front wall
22 is defined by a door panel
150, shown in a closed
position in FIG.
1A and in an open position in FIG. 6. A lower end
152
of the door panel
150 is attached to the housing
20 by a hinge
154.
The door panel
140 can pivot about the hinge
154 between the closed
and open positions. The panel
150 is secured in the closed position by a
door latch
156 affixed to the panel
150. The latch
156 is
released by a finger grip
158 (FIG. 1) located in a recess
159 in
the front face of the door panel
150.
A lower compartment
170, shown in FIG. 6, extends rearward from a rectangular
front opening
171 in the housing
20. The lower compartment
170
is bounded by the side walls
26 and
28, the bottom wall
30
and an inclined rear wall
174. The compartment
170 is further bounded
by the door panel
150 when the door panel
150 is in the closed position.
The lower compartment
170 can be used to store welding accessories such
as gloves
176. The top wall
40 being inclined to face the operator,
along with the lower compartment
170 extending rearward from the front wall
22, provides convenient access to the devices
50,
52,
60,
62 and
64 and the compartment
170 by the operator with minimal
need for the operator to reposition himself.
An upper compartment
180 extends downward from a generally-rectangular
opening
181 in the top wall
40 near the rear wall
24. The
upper compartment
180 is defined by front and rear walls
182 and
184 (FIG.
1B), two side walls
186 and
188, and a bottom
wall
190. The front wall
182 of the compartment
180 is inclined,
extending from the top wall
40 downward and rearward to the bottom wall
190 of the compartment
180. The rear wall
184 of the upper
compartment
180 is a portion of the rear wall
24 of the housing
20.
Similarly, the side walls
186 and
188 of the upper compartment
180
are portions of the side walls
26 and
28 of the housing
20.
The upper compartment
180 can be used to store welding accessories such
as two containers
192 containing welding rods.
The arrangement of the aforementioned features of this embodiment provides several
conveniences. All of the control and display devices
50,
52,
60,
62 and
64 of the welder
30, along with the top storage compartment
180, are located along the same wall
40, the top wall
40.
Consequently, all of these features are conveniently viewed and accessed by the
operator without the operator having to change his position. Viewing and accessing
these features is further facilitated by the top wall
40 being inclined
to face the operator in both the upright and lying positions of the welder, when
the operator is standing or kneeling, respectively.
Another convenience is that the compartments
170 and
180 are
located such that, in either position of the welder
10, the opening
171
and
181 of one of the compartments
170 and
180 faces upward
and the opening
171 and
181 of the other of the compartments
170
and
180 faces horizontally. Specifically, when the welder
10 is in
the upright position (FIG.
2A), the opening
181 of the upper compartment
180 faces upward and the opening
171 of the lower compartment
170
faces horizontally. Similarly, when the welder
10 is in the lying position
(FIG.
2B), the opening
171 of the lower compartment
170 faces
upward and the opening
181 of the upper compartment
180 faces horizontally.
This provides the operator with access to storage both from above and from the
side, in either position of the welder
10.
The first control device
50 is a power switch, shown in FIG. 7, used to
turn the welder
10 on and off. In this example, the power switch
50
is located near the front of the top wall
40, equidistant from the side
walls
26 and
28 and also equidistant from the two jacks
84.
The second control device
52, shown in FIG. 7, is used by the operator
to control the welding current. This device
52 is a crank wheel comprising
a knob
210 projecting from a disk
212. The crank wheel
52
is located along the top wall
40 of the housing
20 and projects through
an opening
213 in the top wall
40. The crank wheel
52 is equidistant
from the side walls
26 and
28 and also equidistant from the two jacks
84. The crank wheel
52 is rotatable about an axis
215 perpendicular
to the top wall
40.
The mechanism that the second control devise
52 uses to control the welding
current is shown in a side view in FIG.
8 and in various perspective views
in FIGS. 9A,
9B and
10. Referring to FIG. 9B, an externally threaded
rotatable lead screw
220 extends axially downward from the crank wheel
52.
It extends through a hole
221 in a stationary block
222 into, and
engaged with, a threaded hole
223 of a sliding block
224. The sliding
block
224 is sandwiched in-between two shunt pieces
226. Each shunt
piece
226 comprises a stack of laminated steel. A shunt assembly
228,
or shunt, comprises the sliding block
222 and the shunt pieces
226.
The shunt
228 has two channels
229, each defined by the sliding block
222 and the shunt pieces
226. Each channel
229 is configured
to closely receive a respective guide rail
230 extending axially downward
from the stationary block
222 to an end piece
232. This enables the
shunt
228 to slide axially along the rails
230 while preventing the
shunt
228 from rotating. As shown in FIG. 8, when assembled, the transformer
core
76 is captured between two extensions
236 of the end piece
232
from below and two transversely-extending extensions
238 of the rails
230
from above.
As indicated by an arrow
233 in FIG. 9A, rotation of the crank wheel
52,
and thus the lead screw
220, about the axis
215 causes the shunt
228 to slide axially downward into or axially upward out of the transformer
core
76. The shunt
228 can thus slide over a predetermined full range
of travel of the shunt
228. The output current is inversely related to the
penetration of the shunt
228 into the core
76. Accordingly, the operator
can control the welding current by rotating the crank wheel
52. Rotating
the crank wheel
52 clockwise decreases the penetration of the shunt
228
into the core
76, which increases the welding current. Conversely, rotating
the crank wheel
52 counterclockwise increases penetration of the shunt
228
into the core
76, which decreases the welding current. Accordingly, the
operator can use the crank wheel
52 to select a nominal welding current
value. The value is only "nominal" because the actual welding current can vary
to some extent based on welding conditions such as the type of welding rod or work piece.
Because the above mechanism employs a lead screw to move of the shunt
228,
the predetermined full range of travel of the shunt
228 corresponds to multiple,
i.e., two or more, revolutions of the crank wheel
52. The range of arcuate
travel of the knob
210 is much longer than the corresponding full range
of linear travel of the shunt
228. This provides several advantages over
mechanisms in which the full range of travel of the shunt corresponds to only one
revolution, or a portion of a revolution, of a control knob or corresponds to linear
motion of a control knob fixed to the shunt. Relative to those other mechanisms,
this embodiment requires less force by the operator to move the shunt
228,
due to the mechanical advantage provided by the lead screw
222. Also, the
lead screw
228 prevents the weight of the shunt
228 from urging the
crank wheel
52 to move out of its set position, thus avoiding the need to
lock the crank wheel
52 in place. Also, the greater arcuate travel of the
knob
210 relative to that of the shunt
228 enables fine-tuning of
the position of the shunt
228.
The first display
60, shown in FIG. 7, is a rotary-type dial gage that
displays the nominal value of the welding current based on the position of the
shunt
228 (FIG.
8). The gage
60 is located along the top wall
40 and is received in a hole
241 in the top wall
40. The gage
60 is located rearward from the crank wheel
52 and equidistant from
the side walls
26 and
28. The gage
60 has a rotatable pointer
242 and a round dial
244 graduated in units of electrical current,
specifically amps. The pointer is rotatable about an axis
245 extending
through the center of the dial
244 and perpendicular to the top wall
40.
The axis
245 of the gage
60 is thus parallel with the axis
215
of the crank wheel
52.
The gage
60 functions through a mechanism shown in side view in FIG.
8
and in various perspective views in FIGS. 9A,
9B and
10. Referring
to FIG. 10, the pointer
242 is connected to a short narrow axially-extending
neck
250. The neck
250 extends through a hole
251 in the dial
244 to a rotatable axially-extending band
252. The band
252
has a wider flat section
254 and a narrower helical section
256.
The helical section
256 extends through a round hole
257 in a stationary
bracket
260 secured to the stationary block
222. The holes
251
and
257 in the dial
244 and the stationary bracket
260 are
diametrically smaller than the width of the flat section
244.
When assembled, as shown in FIG. 9B, the stationary bracket
260 is positioned
such that the wider flat section is captured closely between the dial
244
and the stationary bracket
260. This prevents axial movement of the band
252 while enabling rotation of the band
252 about the axis
215.
The helical section
256 further extends through a slit
263 in a movable
bracket
264 that is attached to the sliding block
224 of the shunt
228. The slit
263 receives the helical section
256 closely
and slidingly. Consequently, axial movement of the shunt
228 causes a corresponding
rotation of the band
252 and thus the pointer
242. Accordingly, as
shown in FIG. 9A, the angular position of the pointer
242 is a function
of the axial position of the shunt
228 relative to the core
76. The
position of the pointer
242 thus indicates the nominal value of the welding current.
The second display device
62, shown in FIG. 7, is a power-on indicator
light located along the top surface
40 to the left of the power switch
50.
The power-on indicator light
62 lights to indicate the welder
10
is turned on.
The third display device
64 is a thermal overload indicator light located
along the top surface
40 to the right of the power switch
50. The
thermal overload indicator light
64 lights to indicate that output current
is being interrupted by an internal thermal protection device (not shown) to protect
the transformer
14 from thermal overload.
While the various features of the invention are shown and described in specific
positions and configurations, many of the features may take on other locations
and configurations, the invention not being limited to the specific examples shown
and described. Furthermore, it should be understood that the features may be used
singly or in any combination.
This written description uses examples to disclose the invention, including
the best mode, and also to enable any person skilled in the art to make and use
the invention. The patentable scope of the invention is defined by the claims,
and may include other examples that occur to those skilled in the art. Such other
examples are intended to be within the scope of the claims if they have elements
that do not differ from the literal language of the claims, or if they include
equivalent structural elements with insubstantial differences from the literal
language of the claims.
*
