Improvements in or relating to the Formation of the Teeth in Rasps.
Year: 1892

page_text: Date of Application, 31st May, 1892
Complete Specification Left, 15th Feb., 1893-Accepted. 25th Mar., 1893
PROVISIONAL SPECIFICATION.
Improvements in or relating to the Formation of the Teeth in
Rasps.
I, ALFRED WEED of Tarrytown, County of Westchester, State of New York,
United States of America, Engineer, at present residing at 18 Nottingham Place,
York Gate, Regent's Park in the County of Middlesex, England, do hereby declare
the nature of this invention to be as follows:-
This invention relates to the formation of the teeth in machine-cut rasps and may
be carried into effect as follows:-
The machine which I prefer to employ is that set forth in the British Letters
Patent No. 16515" granted to Alfred Julius Boult as a communication from me,
and the present invention deals with the particular sequence or arrangement of the
teeth upon the rasp and the apparatus employed for cutting them.
In the before mentioned Specification means were described for cutting the teeth
in the arc of a circle the teeth of each successive row breaking joint with those of
the row preceding and succeeding it; these teeth however were raised at points of
uniform distances apart and as a consequence the teeth occupied positions in parallel
longitudinal lines so that the tendency of the rasp was to cut in grooves instead of
forming a complete cut the width of the rasp. By the present improvements I get
over this difficulty.
In the before named Specification the tool was moved around the arc with a step
by step movement and this movement I retain in one of the new arrangements, but
I vary the actual position of the teeth by holding the blank in a table or carriage
to which, as it traverses longitudinally in a horizontal plane, reciprocating cross
movement, also in a horizontal plane, is imparted. This may be effected by fixing
the blank upon the traversing table and forming the table with one or more wavy
or irregular edges and causing it to bear upon a fixed point or stop by spring or
equivalent pressure which may be applied from the opposite side of the table. The
stop or point may extend for the whole or a small distance, a single point preferably
located opposite the tool however I find sufficient to produce a satisfactory
result.
In a modified arrangement the blank is carried upon the traversing table as
before but no side movement is imparted to the carriage the whole movement being
imparted to the tool. This may be effected by fixing the tool in a tool holder
carried in a more or less vertically reciprocating block or cross head operated from
the driving shaft by an eccentric or the like as explained in the before named
Patent No. 165151. The tool holder may be in the form of a T the stem carrying
the tool and the arms resting in the cross head and being prevented from falling
away from the cross head by a suitable plate or cover connected to or forming part
of a slide adapted to reciprocate within the cross head so as to carry the tool
backwards and forwards across the face of the blank. Various means may be
employed for reciprocating the tool holder or the slide which operates it, a suitable
arrangement consisting in the provision of ratchet teeth with which engage
alternately two spring-controlled pawls carried upon bell-crank-levers separately
pivotted upon the cross head and having their other arms slotted so as to slide upon
fixed pins whose actual position upon the framework can be varied in any required
manner. The slide may be provided with pins adapted to engage with tails
actuating the pawls so that when the end of the traverse is reached the tail engages
with the pin and puts the pawl into or out of gear according to circumstances.
The movement of the carriage may be assisted by a weight passing over a pulley
and its movement may be further controlled by means of one or more racks

page_text: preferably arranged one on each side of the carriage and pawls engaging therewith
and preferably so arranged that when one pawl is in proper engagement with a
tooth the next pawl is at the half distance so as to engage the next tooth when
necessary and thus allow of the requisite movement. The pawls may be alternately
lifted out of engagement with their racks by means of suitable rods and catches
connected with or operated by or from the cross head.
Dated this 31st day of May 1802
W. P. THOMPSON & BOULT,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improvements in or relating to the Formation of the Teeth in Rasps.
I, ALFRED WEED, of Tarrytown, County of Westchester, State of New York,
United States of America, Engineer, at present residing at 18 Nottingham Place,
York Gate, Regent's Park, in the County of Middlesex, England, do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
My invention relates to machines for forming the teeth of rasps and consists of
means for moving the teeth cutting tool step by step from one side to the other of
the blank and for feeding the latter automatically as fully set forth hereinafter and
as illustrated in the accompanying drawings in which
Fig. 1 is a front elevation of an improved rasp cutting machine constructed
according to this invention for making rasps with regularly disposed teeth.
Fig. 2 is a vertical section on the line 2-2, of Fig. 1.
Fig. 3 is a horizontal section on the line 3-3 of Fig. 1.
Fig. 4 is an enlarged view of the tool carriage and adjuncts.
Fig. 5 is a section showing the connections of one of the feed pawls.
Fig. 6 is a front elevation partly in section of the machine as arranged for making
rasps with irregularly disposed teeth.
Fig. 7 is a horizontal section of the same, and
Fig. 8 is an elevation illustrating a modification.
Like letters indicate like parts throughout the drawings.
The general construction and operation of the machine is substantially that set
forth in the Specification of Letters Patent No. 16515 dated 29th September 1891.
There is a tool 1 which is secured detachably in a stock 2, and which operates upon
the blank X, carried by a sliding carriage 15, which is moved in one direction by
means of a weight 17 attached to a chain 18, passing over a guide pulley 19, the
movement of the carriage being effected step by step as hereinafter set forth. The
stock is supported by a sliding carriage 3 upon a head 9, to which a vertical
reciprocating movement is imparted by means of a crank shaft 6 through the
medium of a connecting rod D, the said connecting rod being formed in two parts
or sections preferably screwed right and left handed and joined by a right and left
handed screwed nut by revolving which the length of the connecting rod may be
varied; or the two parts of the connecting rod may be otherwise adjustably
connected together. The sliding head 9 is carried between the vertical portions B
of the frame having a base 119 that supports the sliding carriage 15, and bearings
for the shaft 6 and the stock 2 is normally held in an inclined position determined
by the adjustment of a set screw 31 as in the machine set forth in the aforesaid
Letters Patent.
In the said machine patented as aforesaid means were provided to raise the teeth
of the rasp upon lines which conform to curves. In many instances it is desirable
to raise the teeth upon straight lines and the object of my present invention is to
provide means whereby the teeth will be automatically spaced and formed in lines
extending at right angles across the blank and whereby the blank after the cutting

page_text: of the teeth of one row will be automatically moved to the position necessary for
receiving the first tooth of the succeeding row.
The
Different means may be employed for effecting these movements of the tool
through the medium of the carrier or carriage 3, that supports the stock upon the
head 9 and devices for feeding the said carrier step by step transversely across the
head and for feeding the blank one step after each row of teeth is cut.
carriage 3 may be secured to the head 9 in any suitable manner, but as shown the
said carriage consists of a block dove-tailed and fitting a dove-tailed recess
extending transversely across the face of the head 9, and in connection with the
carrier I make use of a feeder or feeders which it is obvious may be differently
constructed so as to move each one step at one of the movements of the head to
feed the carriage the extent of one tooth or sufficient to carry the tool 1 laterally
to the extent necessary to punch a second tooth after the first has been punched.
As shown the carrier 3 is provided with a rack 40 having two series of teeth 41, 42,
inclined in opposite directions and the feeders are in the form of levers C, shown
as bell-crank levers pivotted each to the head and each having an arm 421 with a
slot in it receiving a pin 43 upon the frame. While the pins 43 may be secured
directly to the frame they are each preferably upon a plate or slide I, secured to
the frame by means of a screw-bolt 44, passing through a slot 45 in the slide, with
a washer and a rubber disc 46, beneath the head of the nut and bearing upon the
slide so that the latter can move vertically under a certain pressure but is normally
held in place. By this means the reciprocating movement of the head 9 vibrates
the levers to the extent permitted by certain adjustable stops 47, at the same time
in case of any binding of the parts the slides I can move to a certain extent so as to
prevent injury or breakage. Any other suitable means of supporting the slides I
so that they shall move under a frictional resistance or the pins 43 so that they shall
yield under a frictional resistance may be used instead of that set forth. Each pin
is adjustable in a slot 48 of the slide Ĭ so as to thereby vary the throw of the feed
levers C.
Each lever acts upon the ratchet plate of the follower through the medium of a
paw 49. Means are employed whereby only one of the pawls will engage with the
teeth of the rack plate at one time so that as the head 9 moves up and down and
the levers 3 are vibrated one of the pawls will engage with one of the racks and
the carrier will be moved to one side until the last tooth engages with the pawl.
After the carrier has thus been carried the full extent in one direction means are
taken for throwing the pawl that has been in operation, out of operation, and the
other pawl is then thrown into operation so that the reciprocation of the head and
the movement of the other feed lever will feed the carrier back in the opposite
direction.
One means of throwing the pawls automatically into and out of operation
consists of pins upon the carrier or rack plate 40. Thus, each of the pawls 49 has
projecting from it an arm 50, which is in position to be struck by pins 51, 52, upon
different parts of the plate 40. In the position shown in Fig. 1, the plate and the
carrier have been moved to their central position the pin 51 at the left, has made
contact with the arm of the left pawl and has thrown it up out of operation. When
the head 9 again moves up, the pawl at the right will be lifted from the tooth with
which it is in engagement in Fig. 1, and when the head comes down the said pawl
will engage the succeeding tooth, and upon the next rising and falling movement
the arm 50 of the pawl at the right will be brought against the pin 51, at the right
and the pawl at the right will be lifted while the pin 52 at the left will be
brought against the arm 50 of the pawl at the left and the latter will be thrown
down into engagement with the rack 41 after which the continued reciprocations
of the head will cause the carrier to be moved towards the right again and so on.
A friction detent is used for holding each pawl in the upper position to which it
is set when thrown out of operation. This friction detent may be of any suitable
character but as shown in Fig. 5, it consists of a spring bolt 54 against which bears
a spring 55, which forces the point of the bolt into a notch 56 in the pawl and

page_text: holds it frictionally in its elevated position until again thrown down as above
described. The carrier 3 is thus moved so as to carry the tool 1 transversely
across the blank moving it one step at each reciprocation of the head and after the
formation of each tooth, first in one direction, and returning it step by step in the
opposite direction after it has reached the edge of the blank. The stops 47 are in
the form of set screws passing through projections on the face of the head 9 so that
by turning said screws the limitation of the stop may be varied.
The longitudinal feeding of the blank or carriage or carrier, which supports the
blank, is effected as follows:-At each side of said carriage is a rack 59, and with
said rack engages a pawl 60 pivotted to a bearing upon the base plate of the
machine, one of the pawls being of such length that when one of them is in engage-
ment with the shoulder of a tooth of one rack the other will be half-way over the
tooth of the other rack so that if the pawl in engagement with a tooth is lifted the
weight 17 will carry the carriage 15 longitudinally until the shoulder of the tooth
of the other rack engages its pawl when the movement will be stopped and so on.
Any suitable means is employed for operating the pawls or lifting them alternately.
Thus to each pawl is secured an elevating rod 61, having a shoulder 62, adapted to
engage a reciprocating lifter 63, a spring 64 tends to hold the two rods out of
engagement with the lifting shoulder 65, 66, of the lifters but as the rack plate 40
approaches the limit of its movement in either direction a pin 75 projecting there-
from makes contact with the adjacent rod 61 and presses the latter outward so that
when the lifter 63, again ascends it will engage with the shoulder of the rod and
lift the same and the pawl.
The lifters 63 may be reciprocated in any suitable manner. As shown they
are in the form of arms upon a rock-shaft 70 having an arm 71 with which is
connected a rod 72 extending from a strap 73 upon an eccentric 74 upon the
shaft 6.
It will therefore be seen that the tool is automatically operated so as to descend
and penetrate the metal and lift the tooth and then ascend after which it moves
laterally to one side and then down again and lifts another tooth and so on till it
approaches the side of the blank after which the blank will be fed one tooth
further onward and the tool will then begin to punch a row of teeth beginning
at the side where it is situated and going on step by step to the opposite side or
edge, after which these operations will be continued as before until the entire blank
is punched.
In the manufacture of rasps by machinery as before described the blank carrier
or the tool is so operated that the rasp teeth are raised at points upon the blank
uniform distances apart, and as a consequence the teeth occupy positions upon
parallel lines so that the tendency of the rasp is to cut in grooves instead of forming
a complete cut the width of the rasp. This may be desirable for some purposes
but for other purposes it may be equally desirable that the rasp should form a
complete cut throughout its width and to construct a rasp for this purpose means
are provided for imparting an irregular movement to the blank or to the tool so
that no one tooth will occupy a position directly in front of the tooth behind it or
midway between any two teeth directly behind it, as fully set forth hereinafter and
as illustrated in Figures 6, 7 and 8.
The carriage 15 working in the guides 10 has pivotted to it at 11 the carrier 12
for the blank X.
One side of the carrier 12 is waved or formed into a series of alternate recesses
and projections 13 and this side or edge bears against a bearing 14, fixed to the
frame and having a rounded end, the side of the carrier being pressed against the
said bearing by the action of a spring 20 supported by the carriage and bearing
against the opposite side or edge of the carrier. As a consequence of this con-
struction at each forward movement of the carrier, together with the carriage the
said carrier will be shifted slightly in one direction or the other, so that the series
of teeth punched across the blank after each forward adjustment of the latter while
of uniform distances apart upon the line upon which they are punched, will be

page_text: irregularly arranged as regards the teeth of the adjacent lines, the extent of the
irregularity depending upon the uniformity or want of uniformity in the arrange-
ment and proportions of the projections and recesses of the bearing face 13. The
tool holder or stock 2 is cranked beneath the head 9 so that as the vertical shaft
on which it is secured is rotated through the medium of the ratchet wheel 21
and other connected parts the tool I will be intermittently moved across the
blank.
In the construction shown in Fig. 8 where the lateral movement of the punch 1
is effected by the intermittent rotation of the ratchet 21 an irregular punching of
the teeth will be effected by making the teeth of the ratchet unequal in length,
and it will be evident that other shifting devices for shifting the lateral position
of the blank or the punch at intervals and independent of the ordinary feed
devices may be employed with like effect, and that they may be varied according
to the construction and character of the rasp punching machine, and I therefore do
not limit myself to the use of the particular shifting means shown.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, I declare that what I
claim is,
1. In a rasp-making machine the combination with the driving crank-shaft 6
and the sliding head 9 supporting the chisel or tool 1 of an extensible connection
rod such as D substantially as described and illustrated in the accompanying
drawings.
2. In a rasp-making machine the combination with the reciprocating head 9 and
tool 1 of a carriage such as 3 for said tool movable transversely upon said head
and means for moving said carriage step by step substantially as described and
illustrated in the accompanying drawings.
3. In a rasp-making machine the combination of the reciprocating head 9 and
tool 1 of a carriage such as 3 supporting said tool and movable transversely upon
the head and means for feeding said carriage automatically step by step first in
one direction and then in another substantially as described and illustrated in the
accompanying drawings.
4. In a rasp-making machine the combination with the reciprocating head 9
sliding carriage 3 supporting the tool 1 and provided with racks such as 41 and 42
levers such as C provided with pawls 49 for engaging said racks means for
reciprocating the levers at each movement of the head and means for throwing
one of the pawls out of engagement with one rack and the other into engagement
with the other rack as the carriage reaches the limit of its movement in either
direction substantially as described and illustrated in the accompanying drawings.
5. In a rasp-making machine the combination with the reciprocating head 9
levers C and pawls 49 of a sliding carriage 3 provided with racks 41, 42 and
pins 51 52 substantially as described and illustrated in the accompanying
drawings.
6. In a rasp-making machine the combination with a reciprocating head 9 of a
sliding carriage 3 levers C and adjustable pins 43 engaging said levers substantially
as described and illustrated in the accompanying drawings.
7. In a rasp-making machine the combination with the reciprocating head 9
sliding carriage 3 levers C and pins 43 of plates such as I supporting said pins and
held in place by frictional supports such as 44 46 substantially as described and
illustrated in the accompanying drawings.
8. In a rasp-making machine the combination with the reciprocating head 9
and sliding carriage 3 of feed devices for moving said carriage upon the head a
carrier 15 for the blank and means for feeding said carrier step by step and
connections between the carrier feeding devices and the carriage substantially as
described and illustrated in the accompanying drawings.
9. In a rasp-making machine the combination with the sliding carriage 3 upon
the head 9 and feed devices for the sliding blank carrier 15 of contact pieces for

page_text: operating said feed devices to move the carrier one step as the carriage reaches
the limit of its movement in either direction substantially as described and
illustrated in the accompanying drawings.
•
10. In a rasp-making machine the combination of the head 9 sliding carriage
provided with pins 75 sliding blank carrier 15 pawls 60 pawl elevating rods such
as 61 provided with shoulders and reciprocating lifters such as 63 adapted to
engage said shoulders substantially as described and illustrated in the accompanying
drawings.
11. A rasp-making machine provided with shifting devices independent of the
feed devices for varying the position of the blank and punch at intervals
substantially as and for the purpose described.
12. In a rasp-making machine the combination with a blank carrier 12 laterally
movable upon its support and shifting means for varying the position of the carrier
independently of the action of the feed devices substantially as described and
illustrated in the accompanying drawings.
13. In a rasp-making machine the combination with a blank carrier 12 having
a bearing edge such as 13 with projections and recesses of a bearing 14 substantially
as described and illustrated in the accompanying drawings.
14. As a new article of manufacture a machine made rasp having teeth irregularly
arranged substantially as and for the purpose set forth.
Dated this 15th day of February 1893.
W. P. THOMPSON & BOULT,
Agents for the Applicant.