| Available in 2 styles
in lengths from 6" to 48". Will grind, with commstones, 1" beyond
base at each end or turn, with turning tool, 2" less than base length at each end. |
At
right: Turning Tool Head
Fig. 5 |
 |
 |
Fig. 1 STRAIGHT:
Used where there are no obstructions
to interfere with crossfeed handle. |
The
Martindale Commutator Grinder assures concentricity of the commutator or slip-ring by
precision grinding while it is turning in its own bearings at operating speeds and
temperatures, with centrifugal force holding each bar in place.
Either tool (Fig. 1 or 8) can be quickly changed from right to left hand operation.
On Fig.1, remove two screws and turn the cross-slide around.
On Fig. 8, the right-angle driving shaft is removed and inserted in the other side if the
right-angle housing, and the grinding Head cross-slide turned around as with Fig. 1.
When grinding use 2" × 2" × 8" Commstones in any of the 5 grades
shown and described under Abrasives: Commstones, Brush Seaters, Sanding Bands, etc.;
Commstones (General Information) and Commstones (Commutator Resurfacing Stones). The
stones will grind 1" beyond the grinder base at each end. and they can be cocked to
get into the corner at the riser.
If very deep grooves must be removed, the Fig. 5 Turning Tool Head may be used. It
is interchangeable with the Grinding Head on either Fig.1 or Fig. 8. The tool holder
should be positioned as indicated in the upper left corner of this page. The top of
the commutator should rotate away from the operator so that if the mounting should slip,
the tool bit would be pushed away from the commutator instead of digging in. It is
necessary to add 4" to the grinder base length when using the Turning Tool. |
 |
 |
|
 |
Power-Drive For Either
Style Grinder
Reduces tedious labor; speed up the job. |
 |
Power-Drive
eliminates the need for the operator to hank crank the head back and forth across the face
of the commutator. |
| Weights: Figs. 1 or 8 with 12" base, Net 29 lbs., Shipping 38 lbs; add
about 2 lbs. for each additional inch. Power Drive unit, Net 27 lbs., Shipping
32lbs. |
|
 |
Fig. 8 RIGHT ANGLE
Used where end frame, fan, etc., would
interfere with crossfeed handle of Fig.1. |
Grinders: (Carrying Case
included with grinders below) |
Catalog Number |
| Commutator Grinding Tool (Fig. 1), w/
10" base or less |
GRDR300* |
| Commutator Turning Tool (Fig.1), w/
10" base or less, with Fig. 5 Head instead of Grinding Head |
GRDR301* |
Right-Angle Grinding Tool (Fig. 8),
w/ 10" base or less |
GRDR400* |
Right-Angle-Turning Tool (Fig. 8),
w/10" base or less, with Fig. 5 Head instead of Grinding Head |
GRDR401* |
For Grinders 10" to 26": add
per
inch over 10" |
GRDR666 |
( Grinder prices 28"
and over on application.)
*Add base length to P/N when ordering
(i.e.:"10",12", etc.) |
Power-Drive and Accessories,
115V., 60 Hz |
GRDR501A |
| 230 V.,50 Hz. |
GRDR501B |
| Turning Tool Head (Fig. 5), including
Tool Holder |
GRDR505 |
| Supports: |
|
| Fig. 2 "L" Support |
GRDR50202 |
| Fig. 6 Wedge Block |
GRDR50206 |
| Fig. 9 "T" Support |
GRDR50209 |
| Extension Handles (Fig. 7): |
|
| 6" |
GRDR50306 |
| 10" |
GRDR50310 |
| Commstones for above: |
|
| 2" × 2" × 8" Plain
Lathe Type |
COMM204** |
** When ordering, specify
cat. no. and grade
(i.e. EC, C, M, F, EF)
(See description under Abrasives/ Commstones) |
|
Fig. 7 Extension Handle |
The Round Stud Supports are both drilled 1-1/4", and fibre bushings are provided for
bushing the hole in the support to the diameter of the brush stud. The bushings also
serve to insulate the Grinder when used on live brush studs.
Adjustable Wedge Blocks usually can be mounted on the brush arms in the same holes by the
same stud bolts that fasten the brush holders, as shown in the illustration.
This extension can be supplied in a 6" or 10" length to extend hand-wheel past
brush rigging or other obstruction, when necessary.
|
Grinders 16" or less require 2 supports
Grinders 18" to 34" require 3 supports
Grinders 36" and over require 4 supports
Grinder bases have mounting holes (3/8" - 16 thread)
on 2-1/4" centers across the base and on 2" centers
along the base for mounting supports.
|
A variable speed gear-motor controlled by a full-wave SCR control is
attached to either Fig. 1 or Fig. 8 grinder by a positive drive
coupling. A reversing switch, mounted on the carriage, is operated by
adjustable stops mounted directly to the bed casting providing positive
drive to the carriage.
|
|
