U.S. patent number 3,610,347 [Application Number 04/841,177] was granted by the patent office on 1971-10-05 for vibratory drill apparatus.
Invention is credited to Nick D. Diamantides, William L. Hinks.
United States Patent |
3,610,347 |
Diamantides , et
al. |
October 5, 1971 |
VIBRATORY DRILL APPARATUS
Abstract
The subject matter of this invention is a rock drill apparatus
whose kinematics is based on the resonance of two massive members
connected through a member possessing the characteristics of a
stiff spring. This resonant system is driven to a high rate of
vibratory motion through an hydromechanical actuator, because of
which the attached bit strikes repeated blows on the rock formation
and thus effects drilling.
Inventors: |
Diamantides; Nick D. (Cuyahoga
Falls, OH), Hinks; William L. (Bath, OH) |
Family
ID: |
25284225 |
Appl.
No.: |
04/841,177 |
Filed: |
June 2, 1969 |
Current U.S.
Class: |
175/56 |
Current CPC
Class: |
E21B
7/24 (20130101) |
Current International
Class: |
E21B
7/24 (20060101); E21B 7/00 (20060101); E21b
005/00 (); B06b 001/18 (); B06b 001/14 () |
Field of
Search: |
;175/55,56 ;173/49
;137/81.5 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Leppink; James A.
Claims
What is claimed is:
1. A vibratory drill assembly as described including
two massive members arranged in opposing oscillatory relation to
one another along a common longitudinal axis,
connecting means engaged with each of said two massive members and
attaching them together, said connective means having the
properties of a stiff spring in the direction of said common axis,
whereby limited axial displacement of the one massive member with
respect to the other results upon the application of axial force
between said massive members, said connecting means having a cross
section transverse to said axis that is different from the cross
sections of either of said two massive members,
a bit drivingly attached to one of said massive members,
a fluid operated actuator producing oscillating force between said
two massive members, including at least one effective piston
chamber to accept pressurized flow cyclically through porting means
from oscillatory converting means acting upon an inlet flow of
pressurized fluid and converting said inlet flow to said cyclic
flow, whereby fluid energy may be converted to vibratory energy
having about the frequency of the resonant oscillatory system
formed by said massive members and said springlike behaving
connecting means,
wherein said stiff springlike connecting means is an elongate metal
member arranged along said longitudinal axis and having a
cross-sectional area transverse to said longitudinal axis that is
substantially constant and substantially minimal over a large
portion of the length of said metal member to define an active
length, said elongate metal member being affixed at one end of said
active length to one of said massive members.
2. A vibratory drill assembly as described including
two massive members arranged in opposing oscillatory relation to
one another along a common longitudinal axis,
connecting means engaged with each of said two massive members and
attaching them together, said connective means having the
properties of a stiff spring in the direction of said common axis,
whereby limited axial displacement of the one massive member with
respect to the other results upon the application of axial force
between said massive members, said connecting means having a cross
section transverse to said axis that is different from the cross
sections of either of said two massive members,
a bit drivingly attached to one of said massive members,
a fluid operated actuator producing oscillating forece between said
two massive members, including at least one effective piston
chamber to accept pressurized flow cyclically through porting means
from oscillatory converting means acting upon an inlet flow of
pressurized fluid and converting said inlet flow to said cyclic
flow, whereby fluid energy may be converted to vibratory energy
having about the frequency of the resonant oscillatory system
formed by said massive members and said springlike behaving
connecting means,
wherein said stiff springlike connecting means includes at least
one elongate metal member that carries force between said two
massive members and is affixed to each of the same at locations
that are respectively spaced along the elongate dimension of said
connecting elongate metal member.
3. A vibratory drill assembly as described including
two massive members being arranged in opposing oscillatory relation
to one another along a common longitudinal axis,
connecting means engaged with each of said massive members and
attaching them together, said connective means having the
properties of a stiff spring in the direction of said common axis,
whereby limited axial displacement occurs between said two massive
members upon the application of axial force between said massive
members,
a bit drivingly attached to one of said massive members,
an actuator producing and applying an axial oscillatory force upon
said two massive members at about the natural frequency of the
resonant system formed by said massive members and said springlike
behaving connecting means, whereby oscillatory energy is imparted
to said resonant system,
and wherein said stiff springlike connecting means includes at
least one elongate member that is affixed to each of said two
massive members at locations that are respectively spaced along the
elongate dimension of said connecting elongate metal member, and
the total cross-sectional area of said connecting means transverse
to said longitudinal axis is substantially less than the likewise
transverse cross-sectional area of said massive members over a
large portion of the distance between said spaced affixation
locations.
4. A vibratory drill assembly as described including
two massive members being arranged in opposing oscillatory relation
to one another along a common longitudinal axis,
connecting means engaged with each of said massive members and
attaching them together, said connective means having the
properties of a stiff spring in the direction of said common axis,
whereby limited axial displacement occurs between said two massive
members upon the application of axial force between said massive
members,
a bit drivingly attached to one of said massive members,
an actuator producing and applying an axial oscillatory force upon
at least one of said two massive members at about the natural
frequency of the resonant system formed by said massive members and
said springlike behaving connecting means, whereby oscillatory
energy is imparted to said resonant system,
and wherein said stiff springlike connecting means includes a
plurality of elongate helical metal members that carry force
between said two massive members and are affixed at locations that
are respectively spaced along the elongate dimension of said
helical metal members.
5. A vibratory drill assembly as described including
two massive members being arranged in opposing oscillatory relation
to one another along a common longitudinal axis,
connecting means engaged with each of said massive members and
attaching them together, said connective means having the
properties of a stiff spring in the direction of said common axis,
whereby limited axial displacement occurs between said two massive
members upon the application of axial force between said massive
members,
a bit drivingly attached to one of said massive members,
an actuator producing and applying an axial oscillatory force upon
at least one of said two massive members at about the natural
frequency of the resonant system formed by said massive members and
said springlike behaving connecting means, whereby oscillatory
energy is imparted to said resonant system,
and wherein said springlike connecting means includes at least one
elongate metal member that is affixed to each of said two massive
members at locations that are respectively spaced along the
elongate dimension of said connecting metal member, and said
elongate metal member is made of a material having a lower modulus
of elasticity than said massive members.
6. The device of claim 1 wherein said elongate metal member has a
tubular cross section and surrounds said massive members over at
least part of their lengths.
7. The device of claim 1 wherein said elongate metal member is
within and laterally supported by said massive members.
8. The device of claim 1 wherein said elongate metal member has a
tubular cross section and surrounds said massive members over at
least part of their length and, in addition, provides lateral
support to said massive members at a location spaced between the
affixation locations at the ends of said active length.
9. The device of claim 8 wherein said lateral support means is
provided by laminated rubber-metal bearings as described.
10. The device of claim 8 wherein each massive member is laterally
supported by a laminated rubber-metal bearing that fills the
annulus between said massive member and the inside surface of said
tubular member, and provides a seal against fluid passage between
them.
11. The device of claim 2 wherein said elongate metal members are
helical and are plural in number arranged in at least one
side-by-side array about said longitudinal axis, as could be
defined by cutting spaced helical slots through the wall of a
tubular member.
12. The device of claim 11 wherein a plurality of said side-by-side
arrays are provided spaced along said longitudinal axis, and the
handedness of said helical elongate metal members are such that a
substantial torsional component of motion about said longitudinal
axis accompanies said limited axial displacement upon the
application of axial force.
13. The device of claim 2 wherein said elongate metal member has a
tubular cross section and surrounds said massive members over at
least part of their lengths.
14. The device of claim 2 wherein said elongate metal members are a
plurality of rods within and laterally supported by said massive
members.
15. The device of claim 2 wherein said oscillatory converting means
includes at least one fluidic oscillator contained within one of
said massive members and ducted to said piston chamber, said
fluidic oscillator having a source chamber fed by said inlet flow,
and interaction chamber communicating with said source chamber, a
pair of output ducts connected to said interaction chamber, the
downstream end of one of said output ducts connected to said piston
chamber and the downstream end of the second of said output ducts
connected to a conduit traversing the second said massive member,
and feedback paths connecting said interaction chamber to points
downstream of said output ducts.
16. The device of claim 15 wherein said second output duct is
connected to said conduit traversing said second massive member by
means of a duct segment, said duct segment forming a gap between
itself and said conduit, said gap having the shape of a cone.
17. The device of claim 2 wherein said oscillatory converting means
includes a mechanical oscillator having at least one nozzle that
forms a fluid jet from said inlet flow of pressurized fluid, said
mechanical oscillator on the one hand being supported relatively to
one of said massive members by axial spring-behaving support means
allowing reciprocating movement and on the other hand being
affected by the movement of the second massive member through a
damper provided between said second massive member and said
mechanical oscillator, said mechanical oscillator reciprocating
through a distance whereby said jets are caused to impinge
cyclically upon passage pairs communicating with said piston
chamber and with a conduit traversing one said massive member.
18. The device of claim 3 wherein said elongate metal member has a
tubular cross section and surrounds said massive members over at
least part of their length and in addition provides lateral support
to said massive members at a location spaced between the affixation
locations at the ends of the active length of said elongate metal
member.
19. The device of claim 18 wherein each massive member is laterally
supported by a laminated rubber-metal bearing that fills the
annulus between said massive member and the inside surface of said
tubular member and provides a seal against fluid passage between
them.
20. The device of claim 4 wherein the handedness of said plurality
of elongate helical metal members is such that a substantial
torsional component of motion about said longitudinal axis
accompanies said limited axial displacement upon the application of
axial force.
21. The device of claim 2 wherein said elongate metal member is a
sleeve that carries a pattern of apertures through its walls.
22. The device of claim 2 wherein said elongate metal member is
within and is laterally supported by said massive members, and one
said massive member telescopes within the other and is aligned and
attached thereto by bearing means.
23. The device of claim 22 wherein the means of said lateral
support and said bearing means include at least one laminated
rubber-metal bearing.
24. The device of claim 22 wherein said bearing means includes
complementally contoured helical tracks in said two massive members
whereby a torsional component of motion accompanies said axial
oscillatory motion.
Description
This invention relates to the field of rock penetrating tools, and
in particular to an improvement of a rock drill.
In applicants' Pat. application, Ser. No. 734,048 filed on June 3,
1968, and found allowable per examiner's communication mailed on
Feb. 18, 1969, there was disclosed a vibratory drill apparatus
driven by fluid means and capable of penetrating rock formations
from the softest to the hardest type, said apparatus being safe in
operation, simple in construction and efficient from the viewpoints
of energy consumption, penetration rate, handling and repairing
simplicity.
More specifically, the above referred to application disclosed the
concept of employing a vibratory drill assembly to be used in
conjunction with conventional oil well rotary drilling apparatus,
including a vibrator mass and a head mass to which the rock
crushing bit is attached on the bottom, these two masses being
coupled together along their common longitudinal or vertical axis
by at least one bearing or connecting member having stiff axial
spring characteristics, whereby limited axial displacement of one
mass with respect to the other would result upon the application of
axial force between said two masses. This system of two vibrating
masses is resiliently attached in the axial direction to an adapter
above them and affixed at the bottom of the drill stem or string,
through a second bearing or coupling member having soft axial
spring characteristics and connecting the stem adapter to one of
the two vibrating masses.
The vibrator and head masses are forced into vibratory motions of
opposing directions by a power oscillator acting upon an inlet flow
of pressurized fluid conventionally supplied through the drill
string and stem adapter and converting the continuous inlet flow
into a cyclic flow. This cyclic flow in turn is fed into one or
more piston chambers formed between the vibrator and the head and
causes said opposing vibratory motion of the vibrator and head
masses. The aforesaid power oscillator may be or either a purely
fluidic type with no moving solid parts or of a resiliently held
and mechanical nature as described in great detail in the aforesaid
application.
While the above system of vibratory drill apparatus fulfills the
basic requirements of effectiveness, simplicity, and long life
under operational conditions, it has become obvious to the
applicants that further improvements beyond the specific
implementation first disclosed can be had and increase of its
utility achieved. In this revised implementation, the aforesaid
connecting member, coupling the vibrator and head masses and having
stiff axial spring characteristics, is constructed in the form of a
long metal sleeve capable of withstanding severe vibratory tensile
stresses for very long periods of time without succumbing to
fatigue.
Construction of an improved vibratory drill apparatus possessing
the aforesaid feature of an elongate stiffly resilient connecting
means accordingly becomes the principle object of this invention,
with other objects becoming more apparent upon reading of the
following specification, considered and interpreted in the light of
the accompanying drawings.
Of the drawings, details of which have been exaggerated to show the
principle of the invention with the maximum degree of clarity;
FIG. 1 is an axial sectional view of the preferred configuration of
the rock drill equipped with a tricone bit, and showing the metal
sleeve connecting member in its relationship to the drill stem,
vibrator and head assembly as well as the fluidic oscillator
feeding a single piston chamber.
FIG. 2 is an axial sectional view of the piston chamber
incorporating the mechanical oscillator.
FIG. 3 is an elevated view illustrating a bidirectionally slotted
connecting member.
FIG. 4 is an elevated view of the connecting member
unidirectionally slotted.
FIG. 5 is an elevated view of the drill illustrating a mechanical
interconnection between the sleeve connecting member and the stem
adapter.
FIG. 6 is a cross-sectional view of the drill comprising the
sleeve-type connecting member and a multiple piston chamber
arrangement.
FIG. 7 is a cross-sectional view of the drill comprising a multiple
piston arrangement and an internal rod-shaped connecting
member.
Referring now to the preferred configuration of our invention shown
in FIG. 1, it will be seen that the rock drill comprises in
combination the stem adapter 10, which is the lower part of the
drill stem (not shown) conventionally used in rock drilling; the
vibrator or upper reciprocating massive member 20; the head or
lower reciprocating massive member 40; the bit 50; and the sleeve
12.
The vibrator 20 is attached resiliently in the axial direction to
the stem adapter 10 by means of the interposed elastomeric bearings
or bushings 11. A telescoping arrangement with annular bearings is
preferred as shown.
A long metal sleeve 12 connects the vibrator 20 and head 40 through
their threaded affixation locations 51. While the sleeve 12
provides the axial strength of the connection between the head and
vibrator masses and carries the stresses generated by the operation
of the drill, the plain rubber or rubber-metal laminated bearings,
or any type of sliding bushing, 16, serve to provide lateral
support means and to secure the centering and alignment between
sleeve, vibrator and head, and by their location in the annulus
between sleeve and massive members to provide sealing against the
pressurized fluid that powers the drill. This fluid, normally being
forced downhole for the purpose of clearing the hole of rock
debris, may be natural gas, air, water, oil or drilling mud as is
the common practice in rock drilling. The fluid enters the drill as
an inlet flow through the inlet opening 21 and is eventually
carried to the bit 50 through the conduits 6a, 6b traversing the
vibrator 20 and head 40.
It will be appreciated that the length and cross-sectional area of
the sleeve 12 are such as to cause the sleeve to behave as a stiff
spring connecting the members 20 and 40. Thus, the sleeve,
vibrator, and head-bit constitute a spring-mass resonant dynamic
system capable of being subjected to sustained vibratory motion in
the axial direction, with the natural frequency of oscillation
established by the magnitudes of the masses involved, the
equivalent resilience constant of the spring, and the
characteristics of the rock against which the drill is
operating.
The laminated bearings 16, on the other hand, consist of a stack of
thin metal laminates interleaved and adhered together by thin
alternating layers of elastic rubber or other rubberlike material,
the layering being in the form of concentric cylinders coaxial with
the main axis of the drill. Such a layer of rubberlike material
bonded between metal laminae can withstand high compressive loads
applied by the metal layers, it being sufficiently thin as to be
restrained from substantially flowing sidewise by its adhesion to
the metal. Elastomeric bearings of this type, however, are capable
of a deformation in shear parallel to the laminae, and behave in a
soft springlike fashion little affected by any compressive forces
that may be applied perpendicularly to the layers.
A single piston chamber 34 is formed between the lower face 20a of
the vibrator 20 and the upper face 40a of the head 40, said piston
chamber, in combination with a subsequently described fluidic or
mechanical oscillator, forming a fluid operated actuator that
imparts oscillatory forces to the two massive members. The space
enclosed by the piston chamber 34 is cyclically filled by the
aforementioned pressurized fluid: as a result, during the half of a
cycle when the flow is switched on the fluid pressure pushes the
vibrator upward and the head downward, both motions taking place
against the spring resistance of the sleeve 12. During the second
half of the cycle when the flow is switched off the restoring force
of the stretched sleeve forces the vibrator downward and the head
upward. The cyclic switching or porting of the pressurized fluid
into the piston chamber 34 and out of it is accomplished in a
self-sustaining manner by means of either a fluidic oscillator 23
shown in FIG. 1, or by means of a mechanical oscillator shown in
FIG. 2. Both oscillator types are called collectively "the
actuator."
The function of the fluidic oscillator is based on the principle of
momentum exchange between fluid jets. Specifically, the pressurized
fluid flowing in the conduit 6a is channeled into the source
chamber 24 from where in a jet form 28 it proceeds into the
interaction chamber 26; from the latter it starts streaming into
the output duct, say 27a, to be discharged into the chamber 34.
During this streaming through the duct 27a part of the fluid is
diverted into the feedback tube 30a and reaches the feedback port
29a after some delay. This diverted flow entering the interaction
chamber 26 impinges perpendicularly onto the main jet 28 causing it
to be diverted or switched over to the output duct 27b. The
trigonometric tangent of the flow 28, as diverted to effect the
switching, is substantially equal to the ratio of the momentum of
the feedback jet to the momentum of the main jet. This feedback
action is repeated through the feedback tube 30b when the main flow
enters the output duct 27b now causing the switching of the main
jet 28 back into the output duct 27a where the cycle is
reinitiated. The length of the cycle is established mainly by the
length and the hydrodynamic impedance of the feedback tubes 30a and
30b. The shape of the interaction chamber 26 in this type of
fluidic oscillator is such as to prevent wall attachment of the
main jet on the sides of this chamber; this prevention is effected
through the recess 26a, 26b. The output 27b of the oscillator,
extending as a duct segment 29 into the upper part of the head 40,
empties into the conduit 6b and eventually though central hole 52
or such jets or courses as may be provided in the bit, onto the
bottom of the rock hole.
The gap 36 between the outer surface of the duct segment 29 and the
inner surface of the conduit 6b, shown exaggerated in FIG. 1, is
given an appropriate width facilitating the venting of the output
of the oscillator 23 during the half cycle when the piston chamber
34 is active. Such venting may be important in making the operation
of the oscillator independent of the load imposed by the particular
rock drilled at the time. The shape of the gap 36 is shown as a
cylindrical annulus is FIG. 1, but it may be of any other shape
facilitating the emptying of the piston chamber 34 during the
inactive half of the oscillation cycle. If the gap 36 has the shape
of an upright cone then, as the volume of the piston chamber is
squeezed during the inactive part of the cycle, the conical shape
causes the gap to become wider allowing the outpouring of the spent
fluid from the piston chamber into the conduit 6b. If, on the other
hand, the gap 36 has the shape of an inverted cone, then during the
above half cycle the spent fluid is to a great extent prevented
from flowing through the narrowed gap and, instead, is forced up
into the interaction chamber 26 through the duct 27a to join the
jet 28 as it exits through the duct 27b. In place of the duct
segment 29 any other connecting and sealing means may be used such
as bellows.
FIG. 2 shows the fluidic oscillator 23 replaced by the pipe-shaped
mechanical oscillator 60 carried within the conduits 6a and 6b by
the elastomeric bearings 15a, 15b. While bearing 15b is soft and
serves only as centering means, the elastomeric bearings 15a have
relatively soft spring characteristics. Jet nozzles 61 through the
lateral wall of the oscillator face the passage pairs 37a, 37b over
a small clearance gap, the oscillator itself being always filled by
the pressurized fluid. The function of the oscillator is greatly
elaborated in he copending application. Depending on the relative
axial position of the vibrator 20 and oscillator 60, and because
the inner openings of the passage pairs 37a, 37b are offset axially
with respect to one another, pressurized fluid from the jet nozzles
61 is forced into either the piston chamber 34 or the lower conduit
6b alternatively, forcing the head 40 and vibrator 20 to
reciprocate in opposite directions. A restricted outlet passage 65b
provides pressures equalization between the interior of the
oscillator 60 and the conduit 6b, and also maintains fluid
circulation thus preventing the forming of deposits within the
oscillator. A damper or dashpot is provided between the oscillator
60 and the vibrator 20 in the form of the piston chamber 75a, 75b
on either side of the piston 75 communicating via the appropriately
sized gap 63 between the piston 75 and the wall of the conduit 6a.
The damper in effect couples the oscillator 60 to the vibrator 20
to create the proper phase of relative motion of the oscillator
with respect to the head 40 and the vibrator 20. It is desirable
that the mass of the mechanical oscillator 60 be made relatively
small so that its position is determined primarily by the coaction
of the damper and of the spring effect of the elastomeric bearing
15a as explained in great detail in the copending application.
Regarding now the connecting member 12, it is suggested that it be
a long metal shell or sleeve of a substantially cylindrical shape,
whose cross-sectional area transverse to the longitudinal axis is
substantially constant and minimal, meaning that, despite
occasional enlargements of cross-sectional area at the points of
connection to the two massive members or at the massive alignment
points midway between the connection points, the area over most of
the sleeve's length is roughly constant and smaller than at the
foresaid points, so that this minimal area experiences the maximum
stress and strain and provides the bulk of the spring action. The
active length of the sleeve, or stiffly elastic member, is defined
to be the length of it between its connection points to each of the
two massive members. The active length is thus subjected to the
alternating compressional and tensile stress as axial oscillation
takes place between the two massive members. By contrast to this
active length the physical length of the sleeve may extend beyond
the connection point to a massive member, one case of such
extension being shown in FIG. 5 for the purpose of coupling the
system to the stem adapter 10. Furthermore, although the connecting
member 12 is described as being made of metal, the term "metal" is
qualified to mean any strong stiffly elastic material such as a
fiber-reinforced or wire or strand-wound synthetic substance or the
like. It is important that the transverse cross-sectional area of
the connecting member is substantially minimal by comparison to the
transverse cross-sectional area of the massive members, or that the
connecting member has a lower modulus of elasticity than the
massive members. Thus the connecting member will undergo
substantially most of the compressional or elongational stretch
when the system is subjected to oscillating axial forces.
In reference to the geometric shape of the connecting member it may
be either that of a solid cylinder as depicted so far, or of a
multiply slotted cylinder as shown in FIGS. 3 and 4. The slots are
arranged in bands or arrays of helical arcs 9a of opposing
handedness as in FIG. 3; the term "handedness" referring to the
direction of a helix as it advances along its axis (as in a
right-handed screw for instance). This slotting of the cylinder
wall in effect creates a plurality of elongate helical metal
members or springs represented by the strong metal ribs 9b, which
are preferably in a side-by-side array, and which, in combination
with the sleeve lengths left unslotted, define the effective spring
constant of the connecting member. The ribs can be viewed by
themselves as elongate metal members carrying force between the two
massive members and affixed at their ends to the remaining part of
the sleeve. If, as shown in FIG, 4, the slots in all or most bands
or arrays are sloped in the same direction with respect to the
generatrix 12a of the cylinder, then they result in a combination
of both linear and torsional springlike behavior of the connecting
member similar to the behavior of the elastomeric bearing 12b shown
in FIG. 13 of the copending application. This dual characteristic
may be exploited for automatically indexing the bit after every
stroke as explained in the copending application. It will be
appreciated that, instead of the bands of slots, a plurality of
apertures of any shape through the sleeve's walls arranged into any
appropriate pattern may be used.
While FIG. 1 of the present application shows the sleeve-type
connecting member 12 in its working arrangement with a single
piston chamber 34, FIG. 6 shows the case where, because of power
requirements, a plurality of piston chambers 34 is necessary
between the head 40 and vibrator 20. In this latter case the piston
chambers are formed between flanges 35 formed on the outer
cylindrical surface of the vibrator and flanges 41 formed on an
inner shell 40a of the head as explained at length in the copending
application. Internal passages for pressurized fluid supply and
drain are supplied within the vibrator and head as shown in the
copending application, and a fluidic oscillator or a mechanical
oscillator (not shown) may be used as porting means.
FIG. 7 shows the connecting member 12 in the form of a rod, instead
of a sleeve, with its threaded ends 51 rigidly affixed to the
vibrator 20 and head 40. The rod, whose primary dynamic function is
to act as a stiff axial spring between the two massive members,
runs through the conduits 6a and 6b. Centering and lateral support
of the rod 12 is secured by the bearings 16 and 16a, of which 16
occupies fully the associated annulus acting as a seal, while the
segments bearings 16a only partially occupy the associated annulus
allowing the flow of pressurized fluid through them.
The set of longitudinal holes 52 arranged about the main axis at
the ends of vibrator 20 and head 40 provide the appropriate
passages for the flow of pressurized fluid. The bearings 17 on the
other hand between the two massive members serve primarily as
seals. Oscillator means, explained in detail in the copending
application are not shown in FIG. 7 for the sake of clarity.
However, it will be understood that the type of fluidic oscillator
as depicted in FIG. 3 of the referenced specification could be
employed, either singly or multiply in parallel, being contained
within the body of vibrator 20 such that its inlet opening,
corresponding to the referenced part 21 communicates with the
internal passage 6a and its output opening or openings at the
bottom of vibrator 20 corresponding to referenced part 22,
discharges flow into the internal passage 6b. Alternately a form of
mechanical oscillator whose design does not interfere with the
connecting rod 12 may be used in this arrangement. The active
length and minimal cross section of the connecting means in the
form of the rod 12 are defined as those of the sleeve in the
previous arrangement. Instead of a single connecting rod along the
apparatus' longitudinal axis between the two massive members, there
may obviously be provided two or more rods off center, each
connecting the two massive together.
We have discussed in the original application, and above by using
elongate spring members cut into a sleeve, means of obtaining an
associated component of torsional motion along with the vibratory
axial motion for purposes of self-indexing in rotation. Yet another
means of doing this can be provided in the present case of a
central rod connecting the two telescoped massive members. It is
related to that in the copending application where in FIG. 13 one
set of supporting laminate bearings are arranged in the annular
space between opposing complementarily contoured faces of the inner
and outer massive members that are not only sloped to create an
axial spring effect but also are arranged in helical tracks. Thus a
torsional component of motion accompanies the axial motion. In the
present case the sloping of the support bearings 17 for axial
spring effect is not used, but the helical tracks on opposing faces
can be provided to obtain a torsional component. All or a part of
the support bearings 17 in FIG. 7 can be so arranged.
While full and complete disclosure of the invention has been set
forth in accordance with the dictates of the patent statutes, it is
to be understood that the invention is not intended to be so
limited. It will be apparent to those skilled in he art that
various changes may be made to the embodiments described herein
without departing from the spirit of the invention or the scope of
the appended claims.
* * * * *