Title: Drive units and drive assemblies
Abstract: A threaded nipple (26) at the closed end of a linear hydraulic motor (12) is received within a recess (82) in a frame member (78). Single clamp members, or individual clamp members (88), have recesses (92) that receive lower portions of the nipples (26). Bolts (94) extend through the clamp members (88) and screw into threaded openings in the frame member (78). This clamps the nipples (26) between the frame member (78) and the removable clamp members (88). End members (22) at the rod ends of the cylinders (12) include keys (66) that are received within recesses (80) formed in another frame member (76). Bolts (76) extend through the end member (22) and screw into threaded openings (84) in the member (76). A mounting frame has transverse mounting frame members (74, 102, 74′, 102′) that are used for mounting the drive assembly in an installation. The mounting frame members (74′, 102′) may have end portions (208, 210, 212, 214, 240, 242) that serve as cells in a trailer installation. The drive units may have a continuous piston-rod (50′) or short piston-rods (50, 50") that are attached to push-rods (14, 14′). The connection may allow a limited amount of pivotal movement between the push-rod (14′) and the piston-rod (50").
Patent Number: 6,994,012 Issued on 02/07/2006 to Foster
| Inventors:
|
Foster; Raymond Keith (Madras, OR)
|
| Assignee:
|
Keith Investments, LLC (Madras, OR)
|
| Appl. No.:
|
375225 |
| Filed:
|
February 26, 2003 |
| Current U.S. Class: |
91/392; 198/750.2 |
| Current Intern'l Class: |
F15B 15/20 (20060101) |
| Field of Search: |
91/392,508
198/750.1,750.2
414/525.1
|
References Cited [Referenced By]
U.S. Patent Documents
| 5263573 | Nov., 1993 | Hallstrom, Jr.
| |
| 5353918 | Oct., 1994 | Foster.
| |
| RE35022 | Aug., 1995 | Foster.
| |
| 5605221 | Feb., 1997 | Foster.
| |
| 5638943 | Jun., 1997 | Foster.
| |
| Foreign Patent Documents |
| 0721901 | Jul., 1996 | EP.
| |
Primary Examiner: Nguyen; Hoang
Attorney, Agent or Firm: Barnard; Delbert J.
Claims
What is claimed is:
1. A liner hydraulic drive unit, comprising:
a transverse frame member having a downwardly directed recess;
a hydraulic cylinder having a sidewall forming a piston chamber, a closed end,
a rod end, a piston head within the piston chamber, a piston rod connected to the
piston head and extending axially of the hydraulic cylinder out through the rod
end of the hydraulic cylinder, and an end member at the closed end of the hydraulic
cylinder having a radial wall portion and a tubular nipple portion extending axially
outwardly from the radial wall portion, said radial wall portion including an outer
surface extending radially outwardly from the nipple;
a removable clamp member connectable to the frame member, said clamp member including
a recess for receiving a portion of said tubular nipple;
said tubular nipple being received in the recess in the frame member with the
radial outer surface of the radial wall portion of the end member being contiguous
a surface of the frame member bordering the recess in the frame member;
said recess in said removable clamp member receiving a portion of said tubular
nipple that is not within the recess in the frame member;
said clamp member having a radial side surface that is contiguous the outer surface
of the radial wall portion of said end member; and
bolts removably connecting the clamp member to the frame member, with the tubular
nipple portion of the end member being received in and clamped by and between the
recess in the frame member and the recess in the clamp member.
2. The linear hydraulic drive unit of claim 1, wherein the tubular nipple includes
a center opening and a tubular fitting is received within said center opening,
said tubular fitting provided a passageway for hydraulic fluid entering into and
leaving from the piston chamber at the closed end of the hydraulic cylinder.
3. The linear hydraulic drive unit of claim 2, wherein the fitting includes a
valve and a valve operator that extends axially into the piston chamber and includes
an inner end portion that is adapted to be contacted by the piston head, wherein
when the piston head is retracted in the piston chamber, it contacts the inner
end of the valve operator and moves the valve operator outwardly and in response
to such movement the valve operator opens the valve, said valve being normally
closed when the piston head is not depressing the valve operator.
4. The linear hydraulic drive unit of claim 3, wherein the valve includes a valve
seat and a valve plug outwardly of the valve seat that is connected to the outer
end of the valve operator, and the valve also includes a compression spring operating
to normally seat the valve plug against the valve seat.
5. The linear hydraulic drive unit of claim 1, wherein an outer surface of the
tubular nipple, the recess in said transverse frame member and the recess in the
removable clamp member having complementary interlocking surfaces which function
to prevent axial movement of the hydraulic cylinder relative to the transverse
frame member and the removable clamp member.
6. A linear hydraulic drive unit, comprising: a transverse frame member having
a downwardly directed recess; a hydraulic cylinder including a closed end and a
rod end, a rod-end member having a base, a radial end wall extending upwardly from
a portion of said base, and a key above another portion of said base, said key
extending axially from the radial end wall;
said rod-end member including a piston rod opening extending through the key
and through a portion of the base; said rod-end member further including a nook
above the base and the key, said nook being bounded on one side by the radial end wall;
said base having a pair of shoulders, one on each side of the key, and a pair
of bolt receiving openings extending through the base and the shoulders;
said frame member having a key receiving recess adapted to snugly receive the
key, and having a side surface that is contiguous the radial end wall of the rod
end member when the key is within the key recess;
said frame member having a pair of shoulders, one on each side of the key recess;
said frame member shoulders confronting the shoulders on the rod-end member when
the key is within the key recess and the side surface is contiguous the radial
end wall of the rod-end member;
said frame member shoulders having bolt receiving openings therein that are alignable
with the bolt receiving openings in the rod-end member when the key is within the
key recess and the side surface of the frame member is contiguous the radial end
wall; and
bolts extendable through the bolt receiving openings in said rod-end member and
the bolt receiving openings in said frame member shoulders; and
said bolts connect the rod-end member of the of the hydraulic cylinder to the
transverse frame member.
7. The linear hydraulic drive unit of claim 6, comprising a second transverse
frame member having a downwardly directed recess adjacent the closed end of the
hydraulic cylinder;
said hydraulic cylinder having an end member at its closed end, said end member
having a radial wall portion and a tubular nipple portion extending axially outwardly
from the radial wall portion, said radial wall portion including an outer surface
extending radially outwardly from the nipple;
a removable clamp member connectable to the second frame member, said clamp member
including a recess for receiving a portion of tubular nipple; said tubular nipple
being received in the recess in the second frame member with the radial outer surface
of the radial wall portion of the end member being contiguous a surface of the
second frame member bordering the recess in the second frame member;
said recess in said removable clamp member receiving a portion of said tubular
nipple that is not within the recess in the second frame member;
said clamp member having a radial side surface that is contiguous the outer surface
of the radial wall portion of said end member; and
bolts removably connecting the clamp member to the frame member, with the tubular
nipple portion of the end member being received in and clamped by and between the
recess in the second frame member and the recess in the clamp member.
8. The linear hydraulic drive unit of claim 7, wherein the tubular nipple includes
a center opening and a tubular fitting is received within said center opening,
said tubular fitting provided a passageway for hydraulic fluid entering into and
leaving from the piston chamber at the closed end of the hydraulic cylinder.
9. The linear hydraulic drive unit of claim 8, wherein the fitting includes a
valve and a valve operator that extends axially into the piston chamber and includes
an inner end portion that is adapted to be contacted by the piston head, wherein
when the piston head is retracted in the piston chamber, it contacts the inner
end of the valve operator and moves the valve operator outwardly and in response
to such movement the valve operator opens the valve, said valve being normally
closed when the piston head is not depressing the valve operator.
10. The linear hydraulic drive unit of claim 9, wherein the valve includes a
valve seat and a valve plug outwardly of the valve seat that is connected to the
outer end of the valve operator, and the valve also includes a compression spring
operating to normally seat the valve plug against the valve seat.
11. The linear hydraulic drive unit of claim 7, wherein an outer surface of the
tubular nipple, the recess in said transverse frame member and the recess in the
removable clamp member having complementary interlocking surfaces which function
to prevent axial movement of the hydraulic cylinder relative to the transverse
frame member and the removable clamp member.
Description
TECHNICAL FIELD
This invention relates to linear hydraulic drive units and to drive assemblies
composed of the linear hydraulic drive units, transverse drive beams and mounting frames.
BACKGROUND OF THE INVENTION
My U.S. Pat. No. Re 35,022, granted Aug. 22, 1995, and entitled Reduced Size
Drive/Frame
Assembly For Reciprocating Floor Conveyor discloses a drive assembly composed of
a small mounting frame, three drive units and three transverse drive beams, one
for each drive unit. My U.S. Pat. No. 5,638,943, granted Jun. 17, 1997 and entitled
Drive Assembly For Reciprocating Slat Conveyor discloses a mounting frame that
includes a downwardly extending center cavity region for receiving the linear hydraulic
drive units.
My U.S. Pat. No. 5,605,221, granted Feb. 25, 1997, discloses a drive assembly
(FIGS. 32-34) comprising a plurality of drive units, a transverse drive beam for
each drive unit, and mounting structure for the drive units. Other prior art drive
units and mounting structure are disclosed by my U.S. Pat. No. 5,353,918, granted
Oct. 11, 1994, by U.S. Pat. No. 5,263,573, granted Nov. 13, 1993 to Olaf A. Hallstrom,
and by European patent application EP 0 721 901 A1, filed by Cargo Handling Systems,
B.V. on Jan. 15, 1996. All of these patents should be carefully considered for
the purpose of putting the present invention into proper perspective relative to
the prior art.
BRIEF SUMMARY OF THE INVENTION
Drive units of the present invention are basically characterized by a hydraulic
cylinder connected to a transverse frame member having a downwardly directed recess.
The hydraulic cylinder has a sidewall forming a piston chamber, a closed end, a
rod end, a piston head within the piston chamber, and a piston rod connected to
the piston head and extending axially of the hydraulic cylinder out through the
rod end of the hydraulic cylinder. An end member is provided at the closed end
of the hydraulic cylinder. The end member has a radial wall portion and a tubular
nipple portion that extends axially outwardly from the radial wall portion. The
radial wall portion includes an outer surface extending radially outwardly from
the tubular nipple. A removable clamp member is connectable to the frame member.
The clamp member includes a recess for receiving a portion of the tubular nipple.
The tubular nipple is received in the recess in the frame member. The radial outer
surface of the radial wall portion of the end member contiguous a surface of the
frame member that borders the recess in the frame member. The recess in the removable
clamp member receives a portion of the tubular nipple that is not within the recess
in the frame member. Bolts removably connect the clamp member to the frame member,
with the tubular nipple portion of the end member being received in and clamped
by and between the recess in the frame member and the recess in the clamp member.
According to an aspect of the invention, the tubular nipple includes an
axial center opening and a tubular fitting is received within said center opening.
The tubular fitting provides a passageway for hydraulic fluid entering into and
leaving from the piston chamber at the closed end of the hydraulic cylinder.
In preferred form, the tubular fitting includes a valve and a valve operator
that
extends axially into the piston chamber and includes an inner end portion that
is adapted to be contacted by the piston head. When the piston head is retracted
into the piston chamber, it contacts the inner end of the valve operator and moves
the valve operator outwardly. In response to such movement, the valve operator
opens the valve. The valve is normally closed when the piston head is not depressing
the valve operator. In preferred form, the valve includes a valve seat and a valve
plug outwardly of the valve seat that is connected to the outer end of the valve
operator. The valve also includes a compression spring that operates to normally
seat the valve plug against the valve seat.
In preferred form, an outer surface of the tubular nipple, the recess in the
transverse
frame member and the recess in the removable clamp member have complementary interlocking
surfaces which function to prevent axial movement of the hydraulic cylinder relative
to the transverse frame member and the removable clamp member.
According to another aspect of the invention, the hydraulic cylinder includes
a rod-end member having a base, a radial end wall extending upwardly from a portion
of said base, and a key extending above another portion of said base and axially
from the radial end wall. The rod-end member also includes a piston rod opening
extending through the key and through a portion of the base. The rod-end member
further includes a nook above the base and the key. The nook is bounded on one
side by the radial end wall. The base includes a pair of shoulders, one on each
side of the key. A pair of bolt-receiving openings extends through the base and
the shoulders. A transverse frame member at the rod end of the hydraulic cylinder
includes a key-receiving recess adapted to snugly receive the key. This frame member
includes a side surface that is contiguous the radial end wall of the rod-end member
when the key is in the key recess. The frame member includes a pair of shoulders,
one on each side of the key recess. The frame member shoulders confront the shoulders
on the rod-end member when the key is in the key recess and the side surface is
contiguous the radial end wall. The frame member shoulders have bolt-receiving
openings therein that are alignable with the bolt-receiving openings in the rod-end
member when the key is within the key recess and the side surface of the frame
member is contiguous the radial end wall of the rod-end member. Bolts extend through
the bolt-receiving openings in the rod-end member and the bolt-receiving openings
in said frame-member shoulders. The bolts connect the rod-end member of the hydraulic
cylinder to the transverse frame member.
Another aspect of the invention is to provide the piston rod with a second
end portion outside of the cylinder body that is connected to a push rod. The piston
rod has a convex, substantially spherical end shape. The push rod includes a bell-shaped
end member having a concave inner end surface substantially conforming to the convex
end shape of the piston rod. It also has a convex outer end surface of substantially
spherical curvature. A coupler is connected to the piston rod axially inwardly
of the convex end of the piston rod. The coupler includes an annular wall portion
surrounding the outer end of the piston rod. The annular wall portion has a concave
inner surface that substantially conforms to the convex outer surface of the bell-shaped
end member on the push-rod. The convex and concave surfaces on said bell-shaped
end member and said concave surface on said coupler and said convex end shape on
said piston-rod together form a ball joint within the coupler by which the piston-rod
is pivotally connected to the push-rod.
In preferred form, at least an end portion of the push rod is tubular and is
internally
threaded. An end member on the push rod member has complementary external threads
that connect to the internal threads in the push-rod. The coupler that is attached
to the piston-rod is axially split into two halves. Bolts extend between the two
halves and secure them together. The piston-rod and the two halves of the coupler
include interlocking portions where the two halves of the coupler contact the piston-rod.
The interlocking portions prevent axial movement of the coupler halves relatively
along the piston-rod. The invention also provides an unique mounting frame having
channel shaped end portions.
Other objects, advantages and features of the invention will become apparent
from the description of the best mode set forth below, from the drawings, from
the claims and from the principles that are embodies in the specific structures
that are illustrated and described.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
Like reference numerals are used to designate like parts throughout the several
views of the drawing, and:
FIG. 1 is a pictorial view of a drive assembly for a reciprocating slat conveyor,
taken from above and looking toward one end and one side of the assembly;
FIG. 2 is another pictorial view of the drive assembly shown by FIG. 1, such
view being taken from below and looking towards the opposite end and the opposite
side of the assembly from what is shown in FIG. 1;
FIG. 3 is a pictorial view of the right end portion of FIG. 2, showing the hydraulic
cylinders spaced below the mounting frame and the mounting bolts spaced from the
ends of the cylinders;
FIG. 4 is a pictorial view of one of the drive units, taken from below the drive
unit and showing the drive rod detached from the piston rod of the cylinder;
FIG. 5 is an enlarged scale fragmentary view of the region of the coupler that
connects the drive rod to the piston rod;
FIG. 6 is a fragmentary view of the left end portion of FIG. 2, with the bearing
assembly for one of the push rods exploded apart and spaced from the transverse
frame member at the end of the mounting frame;
FIG. 7 is a longitudinal sectional view taken through the drive assembly, with
some parts shown in side elevation;
FIG. 8 is an enlarged scale view of the left end portion of FIG. 7;
FIG. 9 is an end view of the mounting frame at the end where the hydraulic cylinders
are connected to the mounting frame;
FIG. 10 is a bottom plan view of FIG. 9;
FIG. 11 is an enlarged scale fragmentary view of the right end portion of FIG.
7, but facing in the opposite direction from FIG. 7, such view showing the outer
end portion of the drive rod extending through a bearing that is connected to the
transverse end member of the mounting frame at the drive rod end of the drive assembly;
FIG. 12 is a transverse sectional view taken substantially long line 12—12
of FIG. 8;
FIG. 13 is a transverse sectional view taken substantially along line 13—13
of FIG. 8;
FIG. 14 is a transverse sectional view taken substantially along line 14—14
of FIG. 8;
FIG. 15 is a view similar to FIG. 3, but showing drive units that have continuous
piston rods;
FIG. 16 is a view substantially like FIG. 4 but of the drive unit shown by FIG. 15;
FIG. 17 is a view generally like FIG. 17 but showing a modified construction
of the coupling between the piston rod and the drive rod;
FIG. 18 is an enlarged scale view of the coupler assembly portion of FIG. 17,
such view showing the fitting that is attached to the drive rod in side elevation
and showing the drive rod and the member that is attached to the piston rod in
longitudinal section;
FIG. 19 is a view similar to the drive unit portion of FIG. 8;
FIG. 20 is an enlarged scale view of the left end portion of FIG. 19;
FIG. 21 is a pictorial view of a modified construction of the transverse frame
member at the cylinder end of the drive assembly, such view being taken from above
and looking towards one end, the outer side and the top of the frame member;
FIG. 22 is an end view of the frame member shown by FIGS. 21-24;
FIG. 23 is a top plan view of the frame member shown by FIGS. 21, 22
and 24;
FIG. 24 is a side elevational view of the frame member shown by FIGS. 21-23; and
FIG. 25 is a pictorial view of the drive assembly shown by FIG. 1, with the
modified construction of the transverse frame members.
DETAILED DESCRIPTION OF THE INVENTION
FIGS. 1-14 show a first embodiment of a drive assembly
10 that is constructed
in accordance with the present invention. It comprises three drive units, each
comprising a linear hydraulic cylinder
12 and a push-rod
14. Each
push-rod
14 includes a semi-cylindrical fitting
18 that is welded
to the push-rod
14. Referring to FIG. 8, each linear hydraulic cylinder
12 includes a tubular sidewall
18, a closed end fitting
20
and a rod-end fitting
22. Closed end fitting
20 and closed radial
end wall
24 and a tubular nipple
26 connect to the end wall
24
and project axially outwardly from it. Each nipple
26 includes an axial
center opening
28. Opening
28 is internally threaded. The outer periphery
40 is externally threaded. An end fitting
32 has an externally threaded
inner end portion
34 that threads into the center opening
28. Fitting
32 has a center opening that receives a valve plug
36 that includes
a valve operator
38. The valve plug
36 is biased towards a valve
seat
40 by a spring
42. Spring
42 is positioned between the
valve plug
36 and an end cap
44. End cap
44 includes an externally
threaded inner end portion that threads into an internally threaded center opening
in the fitting
32. The fitting
32 provides a center passageway through
which hydraulic fluid flows into and out from the working chamber
46.
A piston head
48 is located inside of the tubular sidewall
18. A
piston-rod
50 has an inner end that is connected to the piston-head
48.
Piston-rod
50 extends from the piston-head
48 through the center
opening
52 in the rod-end member
22. Outside of the piston chamber,
the piston-rod
50 extends to an enlarged end member
54. In this embodiment,
another end member
56 is connected to the adjacent end of the push-rod
14.
A two-part clamp
58,
60 serves to connect the two members
54,
56 together. The clamp parts
58,
60 are secured together by
a plurality of bolts
62, as shown by FIGS. 4 and 5.
Referring to FIG. 5, the rod end of member
22, comprises a base
64, a radial wall
6 and a semi-cylindrical key
66. The piston-rod
50 extends through an opening
80 that extends through the key
66
and a portion of the base
64. A nook
72 is formed above the base
64 and the key
66 and adjacent the wall
68. Referring to FIG.
3, the linear hydraulic motors or cylinders
12 are connected to a transverse
mounting frame
74. Frame
74 includes a rod-end frame member
76
and a closed end frame member
78. Each of these frame members
76,
78 includes a plurality of downwardly opening recesses
80,
82,
one for each linear hydraulic motor
12. The recesses
80 are sized
and shaped to receive the keys
66. When the keys
66 are within the
recesses
80, the walls
68 are contiguous the inner surface of the
frame member
76. This is shown by FIG. 8, for example.
The upper halves of the nipples
26 are received within the recesses
82.
Frame member
76 includes bolt-receiving openings
84. Frame member
78 includes bolt-receiving openings
86. Clamp members
88 are
provided for the closed ends of the cylinders
12. Each clamp member
88
includes a pair of bolt-receiving openings
90. When the upper portions of
the nipples
32 are within the recesses
82, the recesses
92
in the clamps
90 are fittable over the lower portions of the nipples
26.
Then the bolts
94 are inserted through first the openings
90 and
then into the openings
86. The openings
86 are internally threaded.
When the bolts
94 are tightened, they thread into the openings
86.
This causes the nipples
26 to be clamped firmly between the two sets of
recesses
82,
92. The recesses
82,
92 and the nipples
30 have interlocking portions that serve to prevent movement of the cylinders
12 relative to the mounting frame
72. The interlocking portions may
be alternating peaks and valleys. The peaks in the recesses
82,
92
fit within valleys formed in the nipples
26. Ridges on the nipples
26
fit in the valleys in the recesses
82,
92. When the bolts
94
are tightened, the interlocking ridges and valleys prevent relative movement of
the cylinders
12 and the frame member
74 in the direction of applied force.
When the nipples
26 are in the recesses
82, the keys
66
are in the recesses
80. Bolts
96 extend through openings
98
(FIG. 5) in the bases
64. The upper ends of the bolts
96 are threaded
and they screw into the openings
84 which are internally threaded. When
the bolts
96 are tightened, the end members
22 are secured to the
frame member
76.
The ends of the push rods
14 that are opposite the piston-rods
50
extend through bearing blocks
100 that are secured to transverse mounting
frame
102. As best shown by FIGS. 6 and 11, the bearing blocks
100
are blocks of plastic, preferably, they are constructed from a high molecular weight
resinous material referred to as umhw plastic. This material is readily available,
is strong, is easily machined to the desired shape, and has exceptionally low surface
friction. It is known to be an excellent bearing material. In the illustrated embodiment,
eight openings
104 are formed in each block
100. The same number
of openings
106 are formed in a metal cover plate
108. The openings
106 are aligned with the openings
104. A bolt
110 extends
through a pair of aligned openings
104,
106 and further extends through
another opening
112 formed in the web portion
114 of the frame member
102. The threaded ends of the bolts
110 pass through the openings
112 and each receives a nut
114, as shown by FIG. 11. Bearing blocks
100 are firmly connected to the frame member
102. The openings
116
and the bearing blocks
100 are sufficiently long to provide a substantial
amount of support for the end portion of the push-rod
14.
As clearly shown by FIG. 2, longitudinal frame members
120,
122
extend between and interconnect the frame members
74,
102. The drive
assembly
10 includes three transverse drive beams
124,
126,
128, one for each drive unit. The transverse drive beams
124,
126,
128 are connected to the push-rods
14, in a known manner. Upper clamp
members are secured to the drive beams
124,
126,
128 above
the push-rods
14. Removable clamps are provided the push-rods
14.
Bolts are used to connect the lower clamp members to the upper clamp members. The
members
16 on the push-rods
14 prevent unwanted axial movement of
the beams
124,
126,
128 relative to the push-rods
14.
The members
16 interlock with the upper clamp members on the beams
124,
126,
128 and prevent relative movement in the direction of applied
force. This concept, including the construction of the members
16, is clearly
disclosed in my U.S. Pat. No. Re. 35,022, granted Aug. 22, 1995, and entitled "Reduced
Size Drive/Frame Assembly For A Reciprocating Floor Conveyor." See also the structure
in my U.S. Pat. No. 5,996,774, granted Dec. 7, 1999 and entitled Drive Beam To
Drive Unit Connections.
FIGS. 15 and 16 show an embodiment in which the drive units have continuous
piston-rods
50′. The ends of the rods
50′ that are
inside of the cylinders
12 are connected to piston-heads within the cylinder
bodies, such as in the manner shown by FIG. 8. The difference is, instead of being
connected to a push-rod, by some sort of joint structure, the piston-rod
50′
extends outwardly from the piston-head
48 and itself serves as the push-rod.
Each piston-rod
50′ may be a single, continuous member. Or, it may
be a continuous member made up of parts that are welded or otherwise connected
together. Each piston-rod
50′ is provided with a member
16′
that interlocks with one of the upper clamp members that is attached to the related
transverse beam
124,
126,
128. Ribs in valleys or some other
suitable structure on the member
16′ interlock with complementary
ribs and valleys or other structure on the upper clamp parts.
FIGS. 17-20 relate to another embodiment in which each drive unit includes
a push-rod
14′ that is connected to a piston-rod
50". The
outer end of the piston-rod
50′ includes a convex end shape
130
that is of substantially spherical curvature. Shape
130 fits into a concave
end cavity
132 of complementary curvature. That is, cavity
132 is
concave and the curvature is a substantially spherical curvature. The cavity
132
is formed in the outer end of a member
134 that has an inner end portion
136 that is cylindrical and is externally threaded. The threads
138
mesh with complementary threads
140 that are formed in an end portion of
the push-rod
14′. The concave surface
132 is a part of a cup-shaped
member
142 that has a convex surface
144 on its outside. A coupler
146 is attached to the outer end of the piston-rod
50". Coupler
146
may be composed of two members, very similar to the members
58,
62
shown in FIG. 5. Piston-rod
50" includes circumferentially extending ribs
and valleys on its outer end portion that is immediately inwardly of the convex
surface
130. The members
146,
148 have semi-cylindrical portions
with complementary ribs and valleys that engage the ribs and valleys on the piston-rod
50" when the coupler parts
146,
148 are connected together
and secured to the piston-rod
50". Members
146,
148 are connected
together by bolts
150. The coupler parts
146,
148 include
an annular wall portion that surrounds the cup-shaped end portion on member
134.
They have concaved surfaces
152,
154 (FIG. 18) that match the curvature
of the surfaces
142,
144. In other words, surfaces
152,
154
have a substantially spherical curvature. The surfaces
130,
132,
142,
144,
152,
154 all share the same center of curvature.
As a result, there can be universal pivotal movement of the push-rod
14′
and the member
134 relative to the piston-rod
50" and the members
146,
148, such pivotal movement occurring about the shared center
of curvature.
In the embodiment of FIGS. 17-20, the cylinder
12" may be fixed against
movement relative to its mounting frame
74 and the outer end of the push-rod
14′ may be held for a substantially straight line movement through
the bearing blocks
100, while some limited pivotal movement is allowed by
the connector between the two rods. The end member
22 provides a long bearing
support of the piston-rod
50". As a result, the cylinder
12" can
withstand substantial side loading imposed by weight on the floor acting on the
transverse beam
124 and the push-rod
14′.
Referring to FIGS. 19 and 20, in this embodiment, a fitting
160
fits within an axial socket
162 formed in the nipple
164 that is
a part of the end member
166 at the closed end of the cylinder
12".
In this embodiment, either a lockwire connection or a threaded connection is used
for securing the member
160 to the member
164. Member or fitting
160 includes a valve seat
168 and a valve plug
170 that moves
towards and away from the valve seat
168. A cup
172 may be provided
outwardly of the valve plug
170. A compression spring
174 may extend
into this cup
172. The opposite end of the spring
174 may make engaging
contact with a removable plug
176. When the parts are in the position shown
by FIG. 19, the spring
174 functions to urge the valve plug
170 against
the valve seat
168. A valve operator
178 is connected to the valve
plug
170 on the side thereof opposite the cup
172. Operator
178
extends from the valve plug
170, axially through passageway
180 and
the member
160 and at its inner end protrudes into the working chamber
182.
When the piston-head
48 and piston-rod
50" are retracted, the side
of the piston-head opposite the rod
50" will contact the end of the operator
170. As piston-head
48 moves closer towards the end of the working
chamber
182, it moves the operator
178 with it. Operator
178
in turn moves valve plug
170 away from the valve seat
168, opening
a fluid passageway between a side port and member
160 and the center passageway
180. When the valve plug
170 is against the valve seat
168,
there is communication between side port
182 and passageway
180.
The valve plug
160 blocks communication between side port
184 and
passageway
180. However, when the operator
178 is depressed, and
valve plug
170 is unseated from the seat
168, there will be communication
between side port
184 and passageway
180.
FIGS. 21-25 show a modified frame structure that can be used by any of the
above described embodiments. As previously described, the frame structure comprises
two transverse mounting frame members
74′,
102′. In
the earlier embodiments, the frame members
74,
102 are of a length
to be used with a center frame trailer. The ends of the frame members
74,
102 are connected to the two longitudinally extending mainframe beams. Then,
cross-frame members are connected to the ends of the frame members
74,
102.
These cross-frame members extend outwardly from the ends of the frame members
74,
102 to the sidewall region of the trailer or other installation in which
the drive assembly is mounted. In the embodiment of FIGS. 21-25, the two frame
members
74′,
102′ are constructed to include the cells.
Referring to FIG. 21, frame member
74′ of two-piece construction.
The pieces or members are designated
190,
192. By way of typical
and therefore non-limitive example, member
190 may be constructed from Swedish
steel measuring 3/16 inch thick. Member
192 may be constructed from Swedish
steel measuring ¼ inch thick. Member
190 is made in the following manner.
A flat sheet of material is provided and an opening is cut in it where member
192
is to be added. Also, the openings
196,
198 are made. These openings
may be made by cutting the flat sheet of steel by use of a plasma cutting machine.
After the flat sheet is cut, it is bent into the shape shown in the drawings. It
is bent to assume the shape of a flanged channel except for the places
194,
196,
198 where the cutouts have been made. In the central part of
the frame member
74′, outwardly on each side of the central cutout
194, the member
74′ includes a web
198, a pair of flanges
200,
202 and a pair of lips
204,
206. Flanges
200,
202 extend substantially perpendicular to web
198 and lips
204,
206. Lips
204,
206 are in coplanar parallelism. Lips
204,
206 are perpendicular to flanges
200,
202 and are parallel
to web
198. In the opposite end region which include the cutouts
196,
198, in the web
199, channel beams
208,
210,
212,
214 are formed. In the sections of the member
74′, the flanges
200,
202 become webs and the lips
204,
206 become flanges.
Also, the remaining side portions
216,
218,
220,
222
of the web
198 become lower flanges for the beam sections
208,
210,
212,
214. Member
192 is cut and then formed into the shape
indicated. It is then set into the center cutout
194 and is welded to the
inner edges of the web
199 and to the members
204,
206 and
the members
200,
202. The member
192 forms a downwardly opening
compartment in which the central portions of the cylinders are received. The frame
members
76,
78 are welded to the sides
74′ at the location
shown in FIG. 3, for example.
Referring to FIG. 25, the transverse mounting frame member
102′
is also formed from a flat sheet of steel. For example, it may be formed from a
sheet of Swedish steel that is about 3/6 inch thick. Regions
230,
232
are cut from the sheet and then the sheet is bent to form web
234 and flanges
236,
238,
240. Thus, the central portion of frame
102
has a channel shape with a deep web. The end portions each have a channel shape
with a shallower web. The lower central portion may extend downwardly between two
mainframe beams. The end channel
240,
242 first extend outwardly
over the tops of the mainframe beams and then continue on to the side of the trailer
or other installation in which the drive assembly is mounted.
The illustrated embodiments are examples of the present invention and, therefore,
are non-limitive. It is to be understood that changes in the particular structure,
materials and features of the invention may be made without departing from the
spirit and scope of the invention. Therefore, it is my intention that my patent
rights not be limited by the particular embodiments that are illustrated and described
herein, but rather invention is to be determined by the following claims, interpreted
according to accepted doctrines of patent claim interpretation, including the use
of the doctrine of equivalents.
*
