Information
-
Patent Grant
-
6785922
-
Patent Number
6,785,922
-
Date Filed
Thursday, December 27, 200123 years ago
-
Date Issued
Tuesday, September 7, 200420 years ago
-
Inventors
-
Original Assignees
-
Examiners
Agents
- Marshall, Gerstein & Borun LLP
-
CPC
-
US Classifications
Field of Search
US
- 005 694
- 005 915
- 601 70
- 601 71
- 601 79
- 601 83
- 601 48
-
International Classifications
-
Abstract
A mattress has an internal support structure and an external cladding that surrounds and covers at least a portion of the support structure. The mattress also has a vibrating device that is coupled to a part of the support structure. The vibrating device has a motor that operates to transmit vibrations throughout the support structure when turned on. The mattress can be adapted to gradually slow at a controlled rate to a complete stop over a period of time when turned off. The mattress can also be adapted to include the vibrating device internally where the device is water resistant. The mattress can also be adapted such that the vibrating device can be easily removed and installed from a pocket provided in the mattress.
Description
FIELD OF THE INVENTION
The invention is generally related to mattresses, and more particularly to a mattress having an internal vibrator and to a method of slowing and stopping a mattress vibrator.
BACKGROUND OF THE INVENTION
Mattresses that have internal vibrators are known. The internal vibrator of such a mattress produces vibrations that can be felt when touching the mattress surfaces. A typical mattress has a skeletal support structure in the form of springs and interconnecting members or links and one or more cladding layers surrounding most or all of the structure. A typical vibrating mattress has a vibrating motor mounted within the mattress and attached to one or more of the springs and/or one or more of the interconnecting members. Vibration of the motor is transmitted to the skeleton structure and then transmitted throughout the skeleton structure.
A typical vibrating device for a mattress turns on and off rather suddenly. The vibrations are immediately transmitted when the device is turned on and immediately stopped when turned off. One problem with such a mattress is that the sudden elimination of vibration can be quite noticeable to an individual that is supported on the mattress. In particular, abrupt elimination of mattress vibration in a child's mattress can disturb or arouse a child sleeping on the mattress. All or most benefits gained by using the vibrating mattress are therefore lost when the child is suddenly awakened upon abrupt shut off the vibrating motor.
Another problem with such mattresses is that the vibrating motor and mechanisms are not protected from contact with liquids. The internal components of an internal vibrating device may be fairly well protected from physical damage when mounted inside a mattress. However, mattresses are typically not constructed as waterproof. A liquid spill on the mattress can seep into the mattress interior and cause damage to the vibrating device and/or components. This can be of particular concern for a child's mattress, because children are susceptible to bed wetting.
A further problem with vibrating mattresses of this type is that it can be difficult to repair or replace the vibrating device and/or its components. Failure of one or more components will require service or replacement. Instead of repairing or replacing the vibrating device, the mattress may simply be discarded prematurely or used without the vibrating feature. In order to access the internal vibrating motor and/or components, the mattress cladding must be removed, damaged, or destroyed. It can be quite costly and time consuming to repair or replace an internal vibrator because of the resultant damage to the mattress. Therefore, once a component fails, the necessary repairs may not be undertaken.
BRIEF DESCRIPTION OF THE DRAWINGS
Exemplary vibrating mattress constructions and methods in accordance with the teachings of the present invention are described and explained in greater detail below with the aid of the drawing figures in which:
FIG. 1
is a partial cut-away and exploded perspective view of one example of a mattress and internal vibrator constructed according to the teachings of the present invention.
FIG. 2
is an exploded view of the internal vibrator shown in
FIG. 1
, and illustrating the motor housing and exterior sleeve.
FIG. 3
is a front view of the internal vibrator shown in FIG.
1
.
FIG. 4
is a back view of the internal vibrator shown in FIG.
1
.
FIG. 5
is a plan view of the internal vibrator motor housing separated into two sections and folded open showing the internal components.
FIGS. 6A and 6B
are graphic illustrations of two exemplary methods according to the teachings of the present invention for gradually stopping a motor of a m a t tress vibrating device.
FIG. 7
is a schematic illustration of one example of a motor electronic circuit with an automatic gradual slow down feature useful for the methods shown in
FIGS. 6A and 6B
.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
One example of a vibrating mattress and a method is disclosed herein according to the teachings of the present invention. The disclosed vibrating mattress generally has an internal vibrating mechanism that can incorporate a number of features. The internal vibrator does not suddenly turn off from an operating condition, but instead can gradually slow to a stop over a predetermined period of time. This prevents abrupt change from a vibrating condition to a non-vibrating condition, and thus reduces or eliminates the likelihood of disrupting or awakening someone on the mattress when the vibrating device turns off. In addition, the disclosed mattress can also include a vibrating device that can be easily removed, repaired, and/or replaced without causing damage to the mattress, without requiring significant time and expense, and without causing an interruption in use of the mattress. Further, the disclosed mattress can have an internal vibrator that is waterproof and thus protected from damage by contact with fluids. Thus, the vibrating device is not susceptible to damage if fluid is spilled on the mattress or if a child wets on the mattress.
Referring now to the drawings,
FIG. 1
is a partial cut-away and exploded perspective view of one example of a mattress and internal vibrator constructed according to the teachings of the present invention. A mattress
10
is shown with a vibrating device
12
removed from the mattress. The mattress
10
generally has an internal skeleton or support structure
13
including a plurality of springs
14
and interconnecting links
16
. Together, the links
16
and springs
14
create the interconnected lattice support structure
13
for the mattress
10
as is generally known to those of ordinary skill in the art. Alternatively, the mattress
10
can include other types of internal support structures
13
such as solid or layered foam materials, other mechanical support constructions, or the like. The internal vibrator and its features are equally suited for many different types and constructions of mattresses, including a solid block of foam.
In the disclosed example, the mattress
10
also has an exterior cladding
18
that covers and defines at least one resting surface
20
and a plurality of side surfaces
22
of the mattress. The mattress
10
typically has a three-dimensional rectangular configuration including the top resting surface
20
, a bottom surface (not shown herein), and four side surfaces
22
as is known to those of ordinary skill in the art. The cladding
18
often covers the entire supporting structure of a mattress on all sides. However, certain types of mattresses, such as box springs, may have cladding only on the top resting surface
20
and, more than likely, the side surfaces
22
. However, box springs are not typically used to define an upper surface on which individuals rest, but instead are intended to support a mattress thereon. The vibrating device
12
of the present invention can alternatively be mounted to a box spring for transmitting vibrations to an upper mattress resting on the box spring.
In the disclosed example, the cladding
18
includes a top or outer layer
24
of a sheathing material. The outer layer may or may not include padding. The mattress also has at least one inner padding layer
26
of a different material. The outer layer
24
, whether padded or not, typically provides an aesthetic appearance that is desired for the mattress. The inner layer
26
typically provides padding so that the individual springs
14
and links
16
are not detectable by an individual on the top resting surface
20
. When the cladding
18
entirely encompasses the support structure
13
of the mattress
10
, the mattress can typically be inverted so that either the top or bottom surface is exposed as the resting surface
20
. With such a mattress construction, the inner layer
26
and outer layer
24
preferably mask the existence of the springs
14
and links
16
of the support structure
13
regardless of which side of the mattress is exposed for use.
The disclosed vibrating device
12
as illustrated in
FIG. 1
is received in a pocket
30
provided in one of the side surfaces
22
of the mattress
10
. The pocket
30
generally has an opening
32
that exposes the pocket interior to the exterior of the mattress. The vibrating device
12
is received through the opening
32
into the pocket
30
. The pocket
30
terminates at a bottom surface
36
. In one example, the bottom surface
36
bears against or otherwise contacts a vibration transmission plate
38
. In another example, the bottom surface
36
of the pocket
30
is the transmission plate
38
. The transmission plate
38
is mechanically connected to one or more of the springs
14
and/or the links
16
. The transmission plate
38
can bear against and directly contact one or more of the support structure elements
14
or
16
, or can be physically attached to one or more of these elements.
The pocket
30
as illustrated in the example of
FIG. 1
is provided in a solid block of material, such as a foam, that is mounted within a portion of the mattress. The layers
24
and
26
of the cladding
18
are shown cut-away, but preferably cover a majority of the block of material for aesthetic appearance, and yet expose the opening
32
and the interior of the pocket
30
. In this example, the pocket material can be a semi-rigid foam and the pocket
30
can be sized to closely contact the vibrating device
12
as described below to retain the vibrating device in the pocket
30
, absorb relatively little vibration, and yet permitting the vibrating device to be easily removed.
As shown in
FIG. 2
, the vibrating device
12
has a motor housing
40
containing various vibration components therein. The device
12
also has a sleeve
42
in which the assembled motor housing
40
is received. The sleeve
42
can be used in conjunction with the pocket
30
, as is disclosed herein. Alternatively, the sleeve can replace the pocket
30
and be installed within the mattress
10
for receiving the assembled motor housing
40
. As another alternative, the motor housing
40
can include the disclosed features of the sleeve
42
. The sleeve
42
can then be eliminated and the assembled motor housing
40
can be mounted directly in the pocket
30
.
In this disclosed example, the sleeve
42
has an opening
44
in its front face
46
. The sleeve also has an interior
48
for receiving the assembled motor housing
40
within the sleeve. In this example, the sleeve
42
includes a bridge
50
spanning between two side walls
52
of the sleeve. The bridge
50
adds structural rigidity and support between the side walls
2
when the motor housing is removed from the sleeve. The motor housing
40
of the vibrating device
12
has a corresponding slot
54
that receives the bridge
50
therein when the assembled motor housing is installed in the sleeve.
Friction between the slot and bridge can be utilized to retain the vibrating device
12
in the sleeve when installed and also to assist in transmitting vibration
30
from the motor housing
40
to the sleeve
80
. A detent mechanism can also be formed on the slot and bridge to provide some positive retention between the sleeve
42
and the motor housing
40
when assembled. The sleeve can be molded or formed as a one-piece unitary structure from any suitable material such as plastic, metal, or the like. The sleeve can also be a two-piece clam shell construction, similar to the motor housing, as described below
In one example as illustrated in
FIG. 1
, the vibrating device
12
can be pre-assembled to include both the sleeve
42
and the assembled motor housing
40
. As illustrated in
FIG. 1
, the fully assembled vibrating device
12
is then installed in the pocket
30
of the mattress
10
. Alternatively, the sleeve
42
can be pre-mounted separately within the pocket
30
, and then the assembled motor housing
40
can be installed in the pocket
30
and sleeve
42
.
As shown in
FIGS. 1 and 2
, the vibrating device
12
in the present disclosed example has a pair of protrusions
56
extending outward from a bottom end
57
of the motor housing
40
. When the vibrating device
12
is received in the pocket
30
, the protrusions
56
are received in corresponding bores or holes
58
provided in the bottom of the pocket
30
and/or in the transmission plate
38
, depending upon the pocket bottom construction as noted above. Vibration from the device
12
is transmitted from the device through the protrusions
56
and into the transmission plate
38
. The protrusions
56
and bores
58
can also assist in guiding the vibrating device
12
into position within the pocket
30
and can be designed to assist in retaining the vibrating device as installed in the mattress, if desired.
As is evident from a review of
FIGS. 1 and 2
, the protrusions
56
can extend from a bottom surface
60
of the sleeve
42
(not shown) or from the bottom end
57
of the motor housing
40
(as shown). If provided on the sleeve, the motor housing need not include protrusions. If provided on the motor housing as shown, the sleeve, if present, can have suitable openings
62
for permitting the protrusions
56
to pass through the sleeve bottom and into the bores
58
.
FIGS. 3 and 4
illustrate a front view and back view, respectively, of the vibrating device
12
.
FIG. 5
illustrates various internal components of the vibrating device
12
and shows the motor housing
40
split in two and folded open. In general, the disclosed motor housing
40
is provided in two sections
40
A and
40
B. The motor housing
40
can be made of metal, plastic, or any other suitable material. The two motor housing sections
40
A and
40
B can be screwed, snapped, welded, bonded, or otherwise suitably fastened together. A seam or parting line
70
of the two assembled sections
40
A and
40
B, if fastened together, is preferably sealed. The intent of the motor housing
40
is to encase the internal components of the vibrating device within a hard protective shell that is also a water resistant or waterproof environment. If the motor housing
40
is not itself at least water resistant, the vibrating device
12
is preferably rendered waterproof when the motor housing
40
is installed in the sleeve
42
.
The vibrating device
12
has at least one exposed power button
72
exposed on a front face
74
for selectively operating parameters of the device. For example, the button
72
can be for turning the vibrating device on and off and for changing speeds of the device. In this disclosed example, a battery cover
76
is also exposed on the front face
74
. As will be evident to those of ordinary skill in the art, the front face
74
and the variety of exposed elements and controls can vary considerably and yet fall within the scope of the present invention. For example, a display (not shown) can be provided indicating various operating perimeters of the device if so desired. These can include the desired run time, the elapsed time, the vibration frequency and/or amplitude, battery life, and the like. In the present example, a light emitting diode (LED)
78
is also provided on the front face
74
. The LED
78
can be illuminated when the device
12
is turned on by the button
72
and can be extinguished when the device is turned off.
The motor housing
40
has an exterior wall
80
that extends between the front and rear faces
74
and
57
, respectively. The exterior wall
80
in the disclosed example is defined by the two motor housing sections
40
A and
40
B when the motor housing is assembled. The motor housing wall
80
and the front and rear faces
74
and
57
completely enclose the vibrating device components within the motor housing. The exterior wall
80
has a contour that substantially matches the shape of the sleeve interior
48
. The motor housing
40
of the vibrating device
12
preferably has a slight interference fit within sleeve interior
48
. Similarly, the sleeve side walls
52
have a contour that essentially matches the shape of the pocket
30
and have a relatively tight fit within the pocket. This will ensure that when the vibrating device is fully installed in the mattress, the device does not move and is closely held within the pocket. This further ensures that substantially all of the vibrations created by the device
12
are transmitted to the transmission plate
38
and not absorbed by the sleeve and/or pocket.
FIG. 5
illustrates one of many possible examples of the internal components of the vibrating device
12
. For example, the disclosed device
12
has a power source
81
such as a battery that selectively powers a motor
82
. The battery is received in a battery receptacle within the housing
40
that is accessible through the battery cover
76
. The motor
82
drives a rotary shaft
84
which carries a weight
86
with a center of gravity that is offset or out of balance relative to a shaft rotation axis. By rotating the shaft and weight, the eccentricity or out-of-balance causes the entire vibrating device
12
to vibrate. The mass of the weight
86
, the amount of offset relative to the rotation axis, and the rotational speed of the motor
82
determine the vibration rate or frequency and the vibration amplitude of the device. The frequency, amplitude, or both can be controlled by component design and by changing motor operation parameters determined as desired. The internal components can also include a switch
88
connected to the button
72
. The switch can be coupled to electronic circuitry that includes a microprocessor
90
to control one or more perimeters of the device. The microprocessor
90
and electronic circuitry can also be connected to the LED
78
to controllably actuate the LED.
The circuitry and microprocessor
90
can be initially designed and programed to operate the motor
82
at one or more than one different rotational speeds. The speeds can be selectively controlled, if desired, by providing various controls on the front face
74
of the motor housing
40
. The microprocessor can alternatively be configured as a programmable processor that a user can selectively program and control operating parameters of the device. The speeds can alternatively be designed to be controlled by the number of times the button
72
and switch
88
are activated. Alternatively, the device can be simply provided with a single speed motor.
The battery access cover
76
and the button
72
can be provided with perimeter seals to inhibit liquid from penetrating the interior of the motor housing
40
. Therefore, the assembled vibrating device
12
is at least water resistant of even waterproof. The device can come in contact with liquid when installed in the mattress and remain unharmed.
In the disclosed example, the motor housing
40
of the device is designed to be removed from the sleeve
42
, if necessary. In one example, the motor housing
40
is held in place within the sleeve by one or more screws located within the bottom or back of the battery compartment. The entire device
12
can be replaced if it fails, or the device can be removed, repaired, and replaced as needed. As disclosed herein, the battery access cover
76
can be removed from the device front face
74
without removing the entire vibrating device from the mattress so that the battery or power source
81
can then be exchanged easily.
In one disclosed example, the microprocessor
90
and electronic circuitry can be designed or programmed to gradually slow the vibrations of the device from an operating level to a complete stop. Depending upon the construction of the motor, shaft, weight, and/or the processor, either the vibration amplitude or the vibration frequency can be gradually changed from a particular operating level to zero amplitude or zero frequency over a predetermined period of time. This time period can vary considerably and yet fall within the scope of the present invention. However, the time period must be lengthy enough that vibrations created by the vibrating device
12
are not abruptly or suddenly stopped as detected by an individual resting on the mattress
10
. In one example, the vibrating device
12
can be gradually slowed to a complete stop from an operating level over about 1 minute. In another example, the time period can be at least about 10 seconds.
The mattress with internal vibrator as disclosed herein produces a number of advantages over prior known vibrating mattresses. First, the vibrations of the mattress are gradually stopped over a period of time. The gradual vibration reduction reduces or eliminates the possibility that an individual resting on the mattress will be suddenly awakened or startled by the abrupt termination of the mattress vibrations. In one example, the motor
82
of the device can be provided as operable at a number of different speeds. The gradual reduction in vibration can be stepped from the highest operating level through the varied intermediate operating levels until reaching a turned off mode (see FIG.
6
A). This step reduction can be conducted over the predetermined period of time. Alternatively, the electronic components can be designed or configured to gradually slow at a continuous, or a non-continuous but non-stepped rate (see FIG.
6
B).
FIG. 7
illustrates one of many possible examples in schematic form of an electronic circuit
100
for the device
12
wherein the motor speed can be gradually and incrementally stepped down in accordance with the charts shown in
FIGS. 6A and 6B
. The schematic shows the motor
82
electrically coupled to a power source
81
such as a pair of D-cell batteries
102
. The disclosed circuit
100
can vary considerably and yet fall within the scope of the invention. The circuit can be simplified from the schematic that is shown in FIG.
7
and described briefly below. Alternatively, the circuit
100
can be more complex to include additional features if so desired.
The disclosed circuit
100
also includes a timer
103
, such as in this example, a 555 electronic timer. The timer
103
can also be in the form of a programmable integrated circuit speed controller or can be incorporated into a microprocessor, such as the processor
90
described generally above. The timer
103
can be a standard chip that is programmed by the manufacturer of the device
12
to operate the vibrating device according to preselected parameters or can be a more complex, user programmable processor.
A switch circuit
104
is coupled to a constant current generator circuit
106
that keeps the circuit
100
linear. The button
72
of the device
12
can be electrically coupled to the switch circuit
104
for activating or deactivating the device. In this example, the batteries
102
produce the supply voltage necessary to operate the circuit
100
and motor
82
when the switch circuit
104
is closed. The supply voltage is also applied across the LED
78
to illuminate the LED indicating that the motor is in the operating mode.
The circuit
100
also has a taper-off circuit
108
that controls a field winding or coil
110
of the motor
82
to thus control and to gradually reduce the motor operational speed. The disclosed electronic timer, in this example, can be selected or set to count down a specific period of motor operation time, such as for example, the last 5 minutes. After the time period, the timer
103
can open a transistor of the taper-off circuit
108
to connect or activate the taper-off circuit. At that time, a capacitor, such as the capacitor
112
of the taper-off circuit
108
begins to charge. As the capacitor
112
charges, the current through the field winding or coil decreases to gradually taper of the motor until it stops. The circuit
100
, and particularly the timer
103
and taper-off circuit
108
can be particularly tailored to produce specific motor slow down characteristics, as desired.
Another advantage produced by the disclosed mattress with internal vibrator is that the mattress is highly suitable for children. The vibrating device
12
as disclosed herein is water resistant and will not be damaged when fluids come in contact with the device. It is known that infants and young children are prone to bed wetting. It is also known that the sleeping patterns of infants and young children are positively affected by use of vibrating mattresses. The disclosed vibrating mattress is especially well suited for use with infants and children because it will not be damaged when the mattress becomes wet. The combination of the waterproof vibrating device
12
and the gradual slow down feature renders the disclosed mattress with internal vibrator especially well suited for children.
A further advantage produced by the disclosed mattress with internal vibrator is that the vibrator, though internally mounted, can be easily removed from the mattress for service, repair, or replacement. Further, the device permits access to the power source
81
such as the batteries
102
without removing the device. The batteries or power source can be easily serviced or replaced. For repair or replacement, the motor housing
40
slips into and out of the sleeve
30
easily and results in no damage to the mattress. In one example, only a single screw need be removed to release the motor housing from the sleeve.
Further, since the device
12
is self-contained and has its own internal power source, it need not be plugged into a regular wall outlet. As a result, the mattress
10
can be utilized virtually anywhere without the need for accessing an external power source.
Although certain methods and mattress examples have been disclosed and described herein in accordance with the teachings of the present invention, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all embodiments of the teachings of the invention fairly falling within the scope of the appended claims, either literally or under the doctrine of equivalents.
Claims
- 1. A mattress comprising:an internal support structure; an external cladding that surrounds and covers at least a portion of the support structure; a mattress vibrating device coupled to a part of the support structure, the vibrating device having a motor that when operating vibrates the part of the support structure and that gradually slows at a controlled rate to a complete stop over a period of time when operation is complete; and a sleeve mounted within the mattress and coupled to the support structure, the motor being removably housed within the sleeve and its vibrations transmitted through the sleeve to the support structure.
- 2. A mattress according to claim 1, wherein the motor can be selectively operated at one of at least two different vibration levels.
- 3. A mattress according to claim 1, wherein the motor gradually slows to a stop at the controlled rate over the predetermined period of time from each of the at least two different vibration levels when operation of the vibrating device is complete.
- 4. A mattress according to claim 1, wherein the period of time over which the motor gradually slows to the complete stop is at least about 10 seconds.
- 5. A mattress according to claim 1, wherein the controlled rate at which the motor gradually slows is a linear, continuous deceleration rate.
- 6. A mattress according to claim 1, wherein the controlled rate at which the motor gradually slows is a stepped down deceleration rate.
- 7. A method of operating a vibrating mattress having a vibrating device with a motor, the method comprising the steps of:mounting a sleeve within the mattress; coupling the sleeve to a mattress support structure; removably sliding the motor into the sleeve such that motor vibrations are transmitted through the sleeve to the support structure; operating the vibrating device to vibrate the mattress; and adapting a part of the vibrating device such that vibration of the vibrating device gradually slows to a stop at a controlled rate over a predetermined period of time when the step of operating is complete.
- 8. A method according to claim 7, wherein the period of time over which the vibrating device gradually slows to the complete stop is at least about 10 seconds.
- 9. A method according to claim 7, wherein the step of operating further comprises:selectively operating the motor at one of at least two different vibration levels, and wherein the vibrating device gradually slows to a stop at the controlled rate over the predetermined period of time from each of the at least two different vibration levels when the step of operating is complete.
- 10. A vibrating mattress comprising:a support structure; a mattress cladding that surrounds and covers at least a portion of the support structure; and a vibrating device including a plurality of components, a motor housing substantially encompassing the plurality of components, and a sleeve mounted internal to part of the mattress and coupled with an element of the support structure, the motor housing removably received within the sleeve and arranged to transmit vibrations through the sleeve for vibrating the mattress, the sleeve being water resistant.
- 11. A mattress according to claim 10, further comprising:a pocket provided within the mattress, the pocket having an opening that exposes a pocket interior to a mattress exterior, the pocket interior being adapted to receive the sleeve therein through the opening.
- 12. A mattress according to claim 10, wherein the plurality of components includes at least a motor, a vibrating element selectively driven by the motor, and a battery providing power to operate the motor.
- 13. A mattress according to claim 10, wherein the sleeve contacts a transmission plate that is in contact with the support structure.
- 14. A mattress according to claim 13, wherein the sleeve substantially surrounds and contacts the motor housing of the vibrating device and is in contact with the transmission plate.
- 15. A mattress comprising:a support structure; a mattress cladding that surrounds and covers at least a portion of the support structure; a self contained vibrating device having an exterior housing and a part of the vibrating device coupled with part of the support structure for vibrating the mattress, the vibrating device when operating vibrates the part of the support structure and gradually slows at a controlled rate to a complete stop over a period of time when operation is complete; and a sleeve having a sleeve interior, the sleeve being mounted within a portion of the mattress and the self contained vibrating device being slidably received within and slidably removable from the sleeve interior.
- 16. A mattress according to claim 15, further comprising:a pocket mounted within the mattress, wherein the sleeve is received in the pocket and a portion of the vibrating device couples with the support structure.
- 17. A mattress according to claim 15, further comprising:a pocket mounted within the mattress, wherein the sleeve and the self contained vibrating device are slidably received within the pocket.
- 18. A mattress according to claim 15, further comprising:a transmission plate in contact with the support structure and with the sleeve.
US Referenced Citations (64)