Claims Analysis
Total Claims: 47
Claim 1
Independent Claim
114 words
An apparatus for wrapping a balloon catheter having a balloon membrane attached to a catheter tube comprising: (a) a housing having a channel to receive at least a portion of the balloon membrane of the balloon catheter; and (b) displaceable clutching means, at least a portion of which being located and positioned in the channel and functioning as follows: (i) during wrapping, engaging and being displaced by the balloon membrane to exert predetermined pressure on the balloon membrane to aid in the wrapping of the balloon membrane as the wrapping apparatus is rotated relative to the balloon catheter yet, and (ii) after wrapping, permitting relatively free rotation of the balloon membrane within the channel.
Claim 2
Independent Claim
114 words
An apparatus for wrapping a balloon catheter having a balloon membrane attached to a catheter tube comprising: (a) a housing having a channel to receive at least a portion of the balloon membrane of the balloon catheter; and (b) displaceable clutching means, at least a portion of which being located and positioned in the channel and functioning as follows: (i) during wrapping, engaging and being displaced by the balloon membrane to exert predetermined pressure on the balloon membrane to aid in the wrapping of the balloon membrane as the wrapping apparatus is rotated relative to the balloon catheter yet, and (ii) after wrapping, permitting relatively free rotation of the balloon membrane within the channel.
Claim 3
Dependent Claim
176 words
A wrapping apparatus for a balloon catheter having a catheter tube attached to a balloon membrane with a central section and two side leaves, comprising: (a) a housing having a central and two side passages, the central and two side passages being located in communication with each other, the central passage being configured to surround at least a portion of the central section of the balloon membrane and the side passages being configured to surround at least a portion of the respective side leaves of the balloon membrane; and (b) displaceable clutching means at least aa portion of which being located and positioned in said central passage and functioning as follows: (i) during wrapping, engaging the balloon membrane, being displaced by the wrapping balloon membrane, and exerting predetermined pressure on said balloon membrane along its length to aid in the wrapping of the balloon membrane as the wrapping apparatus is being rotated relative to the balloon catheter, and (ii) after a predetermined degree of wrapping, permitting relatively free rotation of the balloon membrane within the housing.
Claim 4
Dependent Claim
176 words
A wrapping apparatus for a balloon catheter having a catheter tube attached to a balloon membrane with a central section and two side leaves, comprising: (a) a housing having a central and two side passages, the central and two side passages being located in communication with each other, the central passage being configured to surround at least a portion of the central section of the balloon membrane and the side passages being configured to surround at least a portion of the respective side leaves of the balloon membrane; and (b) displaceable clutching means at least aa portion of which being located and positioned in said central passage and functioning as follows: (i) during wrapping, engaging the balloon membrane, being displaced by the wrapping balloon membrane, and exerting predetermined pressure on said balloon membrane along its length to aid in the wrapping of the balloon membrane as the wrapping apparatus is being rotated relative to the balloon catheter, and (ii) after a predetermined degree of wrapping, permitting relatively free rotation of the balloon membrane within the housing.
Claim 5
Dependent Claim
37 words
The wrapping apparatus of claim 2 wherein the clutching means comprises: (a) a shoe; and (b) biasing means for biasing the shoe toward the balloon membrane with a predetermined pressure while the balloon membrane is being wrapped.
Claim 6
Dependent Claim
16 words
The wrapping apparatus of claim 3 wherein the shoe runs the length of the central passage.
Claim 7
Dependent Claim
29 words
The wrapping apparatus of claim 3 wherein the shoe has a first surface portion which is accurately configured to contact the balloon membrane as the balloon membrane is wrapped.
Claim 8
Dependent Claim
24 words
The wrapping apparatus of claim 5 wherein the first surface portion of the shoe has at least one rib which contacts the balloon membrane.
Claim 9
Dependent Claim
13 words
The wrapping apparatus of claim 3 wherein the biasing means comprises a spring.
Claim 10
Dependent Claim
13 words
The wrapping apparatus of claim 3 wherein the biasing means comprises foam rubber.
Claim 11
Dependent Claim
18 words
The wrapping apparatus of claim 2 wherein the housing is approximately the same length as the balloon membrane.
Claim 12
Dependent Claim
17 words
The wrapping apparatus of claim 2 wherein the housing has two portions releasably secured to each other.
Claim 13
Dependent Claim
35 words
The wrapping apparatus of claim 10 wherein the first housing portion includes at least a portion of the central passage and the second housing portion includes at least a portion of the two side passages.
Claim 14
Dependent Claim
40 words
The wrapping apparatus of claim 10 wherein the second housing portion includes a fourth passage communicating with the other passages, said fourth passages being contiguous with the central passage such that said central and fourth passages surround the balloon membrane.
Claim 15
Dependent Claim
20 words
The wrapping apparatus of claim 12 wherein said fourth passage is arcuately configured to contact the balloon membrane during wrapping.
Claim 16
Dependent Claim
25 words
The wrapping apparatus of claim 13 wherein at least one rib is positioned along the length of the fourth passage to contact the balloon membrane.
Claim 17
Dependent Claim
79 words
The wrapping apparatus of claim 2 wherein the clutching means comprises at least one flexible vane means at least a portion of which is secured to the housing and projecting from the housing inwardly into the central passage to engage the balloon membrane and exert a predetermined pressure on the balloon membrane while wrapping yet permit relatively free rotation of the balloon membrane within the wrapping apparatus after the balloon membrane is wrapped to a predetermined amount of wrap.
Claim 18
Dependent Claim
51 words
The wrapping apparatus of claim 15 wherein the clutching means further comprises at least one shoulder means at least a portion of which projects within the central passage and has a length sufficient to maintain at least a portion of the balloon membrane at a predetermined position within the central passage.
Claim 19
Dependent Claim
35 words
The wrapping apparatus of claim 15 wherein there are at least two generally opposing shoulders projecting radially inwardly in the central passages, and of a length sufficient to centralize the balloon membrane therebetween during wrapping.
Claim 20
Dependent Claim
16 words
The wrapping apparatus of claim 17 wherein the shoulders run the length of the central passage.
Claim 21
Dependent Claim
64 words
The wrapping apparatus of claim 15 wherein the clutching means comprises at least two flexible vanes secured to the housing and projecting tangentially inwardly into the central passage so as to contact and provide predetermined pressure onto the balloon membrane during wrapping yet allow the balloon membrane relatively free rotation within the wrapping apparatus after the balloon membrane is wrapped to a predetermined degree.
Claim 22
Dependent Claim
70 words
The wrapping apparatus of claim 2 wherein the clutching means comprises at least two flexible and centrally opposing vanes secured to the housing and projecting from the housing inwardly into the central passage such that the vanes contact the balloon membrane during wrapping and provide a predetermined pressure onto the balloon membrane which aids in wrapping yet permits the wrapped balloon membrane to rotate relatively free within the wrapping apparatus.
Claim 23
Dependent Claim
30 words
The wrapping apparatus of claim 20 wherein at least a portion of each vane is configured to flex radially outwardly as the diameter of the balloon membrane increases during wrapping.
Claim 24
Dependent Claim
16 words
The wrapping apparatus of claim 21 wherein the vanes run the length of the central passage.
Claim 25
Dependent Claim
14 words
The wrapping apparatus of claim 20 wherein the vanes are integral with the housing.
Claim 26
Dependent Claim
15 words
The wrapping apparatus of claim 2 wherein the passages run the length of the housing.
Claim 27
Dependent Claim
159 words
A wrapping apparatus for an intra-aortic balloon catheter having a balloon membrane attached to a catheter tube, comprising: (a) a housing having: (i) an upper portion with a channel; and (ii) a lower portion with a channel; said upper portion and lower portions being releasably secured together so that the channels form a passage for surrounding at least a portion of the balloon membrane; and (b) displaceable clutching means, at least a portion of which being located and positioned in the passage and functioning as follows: (i) during wrapping, for contacting the wrapping balloon membrane, being displaced by the balloon membrane, and exerting predetermined pressure on the balloon membrane while the wrapping apparatus is rotated relative to the balloon catheter in an amount of rotations sufficient to wrap the balloon membrane about its longitudinal axis, and (ii) when the balloon membrane achieves a predetermined degree of wrapping, permitting relatively free rotation of the balloon membrane within the wrapping apparatus.
Claim 28
Dependent Claim
159 words
A wrapping apparatus for an intra-aortic balloon catheter having a balloon membrane attached to a catheter tube, comprising: (a) a housing having: (i) an upper portion with a channel; and (ii) a lower portion with a channel; said upper portion and lower portions being releasably secured together so that the channels form a passage for surrounding at least a portion of the balloon membrane; and (b) displaceable clutching means, at least a portion of which being located and positioned in the passage and functioning as follows: (i) during wrapping, for contacting the wrapping balloon membrane, being displaced by the balloon membrane, and exerting predetermined pressure on the balloon membrane while the wrapping apparatus is rotated relative to the balloon catheter in an amount of rotations sufficient to wrap the balloon membrane about its longitudinal axis, and (ii) when the balloon membrane achieves a predetermined degree of wrapping, permitting relatively free rotation of the balloon membrane within the wrapping apparatus.
Claim 29
Dependent Claim
170 words
A wrapping apparatus for an intra-aortic balloon catheter having a catheter thus attached to a balloon membrane, comprising: (a) an elongated housing having a channel with a central passage and at least one side passage all passing the length of the housing to receive and surround at least a portion of the balloon membrane when the balloon membrane is in an unwrapped condition; and (b) at least one flexible vane means projecting from the housing inwardly into the channel and functioning as follows: (i) during wrapping, engaging the balloon membrane, being displaced by the wrapping balloon membrane, and exerting predetermined pressure on the balloon membrane as the wrapping apparatus is rotated relative to the balloon catheter to wrap the balloon membrane along its length, said flexible vane means being sufficiently flexible to bend as the diameter of the wrapping balloon membrane increases, and (ii) after rotating the wrapping apparatus at least by a predetermined member of revolutions, permitting relatively free rotation of the wrapped balloon membrane within the wrapping apparatus.
Claim 30
Dependent Claim
170 words
A wrapping apparatus for an intra-aortic balloon catheter having a catheter thus attached to a balloon membrane, comprising: (a) an elongated housing having a channel with a central passage and at least one side passage all passing the length of the housing to receive and surround at least a portion of the balloon membrane when the balloon membrane is in an unwrapped condition; and (b) at least one flexible vane means projecting from the housing inwardly into the channel and functioning as follows: (i) during wrapping, engaging the balloon membrane, being displaced by the wrapping balloon membrane, and exerting predetermined pressure on the balloon membrane as the wrapping apparatus is rotated relative to the balloon catheter to wrap the balloon membrane along its length, said flexible vane means being sufficiently flexible to bend as the diameter of the wrapping balloon membrane increases, and (ii) after rotating the wrapping apparatus at least by a predetermined member of revolutions, permitting relatively free rotation of the wrapped balloon membrane within the wrapping apparatus.
Claim 31
Dependent Claim
29 words
The wrapping apparatus of claim 26 wherein the clutching means further comprises at least two shoulders respectively projecting from the upper and lower housing portions into the central passage.
Claim 32
Dependent Claim
26 words
The wrapping apparatus of claim 27 wherein there are two side passages, and the central and two side passages run the length of the wrapping apparatus.
Claim 33
Independent Claim
214 words
An apparatus for wrapping an intra-aortic balloon catheter having a catheter tube sealidly attached to a balloon membrane to permit fluidic communication therebetween, the balloon membrane having a central section and two side leaves, comprising: (a) a housing having: (i) an upper portion with a channel; and (ii) a lower portion with a channel; said upper portion and lower portions releasably secured together so that the channels form a central passage and at least one side passage, the central passage being located and configured to receive and surround the central section of the balloon membrane and the side passage being located and configured to receive and surround the side leaves of the balloon membrane; and (b) displaceable clutching means which includes at least two flexible vanes projecting respectively from the upper and lower portions of the housing inwardly into the central passage, and which functions: (i) during wrapping, to engage the balloon membrane and be displaced by the wrapping balloon membrane to provide predetermined pressure onto the balloon membrane as the wrapping apparatus is rotated relative to the balloon catheter to wrap the balloon membrane along its length yet, (ii) after wrapping the balloon membrane to a predetermined degree of wrapping, to allow the balloon membrane to rotate relatively freely within the wrapping apparatus.
Claim 34
Independent Claim
214 words
An apparatus for wrapping an intra-aortic balloon catheter having a catheter tube sealidly attached to a balloon membrane to permit fluidic communication therebetween, the balloon membrane having a central section and two side leaves, comprising: (a) a housing having: (i) an upper portion with a channel; and (ii) a lower portion with a channel; said upper portion and lower portions releasably secured together so that the channels form a central passage and at least one side passage, the central passage being located and configured to receive and surround the central section of the balloon membrane and the side passage being located and configured to receive and surround the side leaves of the balloon membrane; and (b) displaceable clutching means which includes at least two flexible vanes projecting respectively from the upper and lower portions of the housing inwardly into the central passage, and which functions: (i) during wrapping, to engage the balloon membrane and be displaced by the wrapping balloon membrane to provide predetermined pressure onto the balloon membrane as the wrapping apparatus is rotated relative to the balloon catheter to wrap the balloon membrane along its length yet, (ii) after wrapping the balloon membrane to a predetermined degree of wrapping, to allow the balloon membrane to rotate relatively freely within the wrapping apparatus.
Claim 35
Independent Claim
112 words
An apparatus for wrapping a balloon catheter having a balloon membrane attached to a catheter tube, comprising: (a) a housing having a channel with at least two passages to receive portions of the balloon membrane; and (b) displaceable clutching means at least a portion of which being located and positioned in the channel and functioning as follows: (i) during wrapping, engaging the balloon membrane, being displaced by the wrapping balloon membrane, and exerting predetermined pressure on the balloon membrane to enable the balloon membrane to wrap as the wrapping apparatus is rotated relative to the balloon catheter, and (ii) after wrapping, permitting relatively free rotation of the balloon membrane within the channel.
Claim 36
Independent Claim
112 words
An apparatus for wrapping a balloon catheter having a balloon membrane attached to a catheter tube, comprising: (a) a housing having a channel with at least two passages to receive portions of the balloon membrane; and (b) displaceable clutching means at least a portion of which being located and positioned in the channel and functioning as follows: (i) during wrapping, engaging the balloon membrane, being displaced by the wrapping balloon membrane, and exerting predetermined pressure on the balloon membrane to enable the balloon membrane to wrap as the wrapping apparatus is rotated relative to the balloon catheter, and (ii) after wrapping, permitting relatively free rotation of the balloon membrane within the channel.
Claim 37
Independent Claim
135 words
An apparatus for wrapping a balloon catheter having a balloon membrane attached to a catheter tube, comprising: (a) a housing having a channel to receive at least a portion of the balloon membrane; and (b) displaceable clutching means having at least one vane means projecting from the housing inwardly into the channel to divide the channel into at least two passages and functioning as follows: (i) during wrapping, said vane means engaging the balloon membrane, being displaced by the wrapping balloon membrane, and exerting predetermined pressure onto the balloon membrane to aid in wrapping the balloon membrane while the wrapping apparatus is rotated relative to the balloon catheter, and (ii) after wrapping by a predetermined amount, said vane means being of sufficient flexibility to permit relatively free rotation of the balloon membrane within the channel.
Claim 38
Independent Claim
135 words
An apparatus for wrapping a balloon catheter having a balloon membrane attached to a catheter tube, comprising: (a) a housing having a channel to receive at least a portion of the balloon membrane; and (b) displaceable clutching means having at least one vane means projecting from the housing inwardly into the channel to divide the channel into at least two passages and functioning as follows: (i) during wrapping, said vane means engaging the balloon membrane, being displaced by the wrapping balloon membrane, and exerting predetermined pressure onto the balloon membrane to aid in wrapping the balloon membrane while the wrapping apparatus is rotated relative to the balloon catheter, and (ii) after wrapping by a predetermined amount, said vane means being of sufficient flexibility to permit relatively free rotation of the balloon membrane within the channel.
Claim 39
Independent Claim
183 words
A method for wrapping a balloon catheter having a catheter tube sealidly attached to a balloon membrane for fluidic communication therebetween said balloon membrane having a central section and two side leaves, the method comprising: (a) evacuating gas from the balloon catheter so as to collapse the balloon membrane; (b) inserting the balloon membrane into a wrapping apparatus having: (i) a housing with a channel to receive at least a portion of the balloon membrane; and (ii) displaceable clutching means at least a portion of which being located and positioned in the channel and functioning as follows: (1) during wrapping, engaging the balloon membrane, being displaced by the balloon membrane and exerting predetermined pressure on the balloon membrane to wrap the balloon membrane when the wrapping apparatus is rotated relative to the balloon catheter, and (2) after wrapping permitting relatively free rotation of the balloon membrane within the channel; and (c) rotating the wrapping apparatus relative to the balloon membrane by at least a predetermined number of revolutions to engage the clutching means with the balloon membrane and thereby wrap the balloon membrane.
Claim 40
Independent Claim
183 words
A method for wrapping a balloon catheter having a catheter tube sealidly attached to a balloon membrane for fluidic communication therebetween said balloon membrane having a central section and two side leaves, the method comprising: (a) evacuating gas from the balloon catheter so as to collapse the balloon membrane; (b) inserting the balloon membrane into a wrapping apparatus having: (i) a housing with a channel to receive at least a portion of the balloon membrane; and (ii) displaceable clutching means at least a portion of which being located and positioned in the channel and functioning as follows: (1) during wrapping, engaging the balloon membrane, being displaced by the balloon membrane and exerting predetermined pressure on the balloon membrane to wrap the balloon membrane when the wrapping apparatus is rotated relative to the balloon catheter, and (2) after wrapping permitting relatively free rotation of the balloon membrane within the channel; and (c) rotating the wrapping apparatus relative to the balloon membrane by at least a predetermined number of revolutions to engage the clutching means with the balloon membrane and thereby wrap the balloon membrane.
Claim 41
Dependent Claim
47 words
The method of claim 32 wherein the channel of the wrapping apparatus has at least two passages, the side leaves of the balloon membrane being inserted into at least one of said passages and the central section of the balloon membrane being inserted into the other passage.
Claim 42
Independent Claim
214 words
A method for wrapping a balloon catheter having a catheter tube sealidly attached to a balloon membrane for fluidic communication therebetween, said balloon membrane having a central section and two side leaves, the method comprising: (a) evacuating gas from the balloon catheter so as to collapse the balloon membrane; (b) inserting the balloon membrane into a wrapping apparatus having: (i) a housing with a central and at least one side passage; and (ii) flexible vane means projecting from the housing inwardly into the central passage for engaging the balloon membrane, being displaced by the wrapping balloon membrane, and exerting predetermined pressure on the balloon membrane, said balloon membrane being inserted into the wrapping apparatus such that at least one side passage surrounds at least one of the side leaves of the balloon membrane and the central passage surrounds the central section of the balloon membrane; (c) rotating the wrapping apparatus relative to the balloon catheter so as to wrap the balloon membrane; and (d) to the vane means, (i) during wrapping engaging the balloon membrane, and exerting a predetermined pressure on the balloon membrane as the wrapping apparatus is rotated relative thereto yet, said vane means being displaced by the wrapping balloon membrane, (ii) after wrapping, permitting relatively free rotation of the balloon membrane.
Claim 43
Independent Claim
214 words
A method for wrapping a balloon catheter having a catheter tube sealidly attached to a balloon membrane for fluidic communication therebetween, said balloon membrane having a central section and two side leaves, the method comprising: (a) evacuating gas from the balloon catheter so as to collapse the balloon membrane; (b) inserting the balloon membrane into a wrapping apparatus having: (i) a housing with a central and at least one side passage; and (ii) flexible vane means projecting from the housing inwardly into the central passage for engaging the balloon membrane, being displaced by the wrapping balloon membrane, and exerting predetermined pressure on the balloon membrane, said balloon membrane being inserted into the wrapping apparatus such that at least one side passage surrounds at least one of the side leaves of the balloon membrane and the central passage surrounds the central section of the balloon membrane; (c) rotating the wrapping apparatus relative to the balloon catheter so as to wrap the balloon membrane; and (d) to the vane means, (i) during wrapping engaging the balloon membrane, and exerting a predetermined pressure on the balloon membrane as the wrapping apparatus is rotated relative thereto yet, said vane means being displaced by the wrapping balloon membrane, (ii) after wrapping, permitting relatively free rotation of the balloon membrane.
Claim 44
Independent Claim
214 words
An apparatus for wrapping an intra-aortic balloon catheter having a catheter tube sealidly attached to a balloon membrane to permit fluidic communication therebetween and a stylet passing through the balloon membrane and at least into the catheter tube, comprising: (a) a housing having: (i) an upper portion with a channel; and (ii) a lower portion with a channel; said upper portion and lower portions being releasably secured together so that the channels form a central passage and at least one side passage, the central passage being located and configured to receive and surround the stylet and a portion of the balloon membrane and the side passage being located and configured to received and surround another portion of the balloon membrane; and (b) displaceable clutching means which includes at least two flexible vanes projecting respectively from the upper and lower portions of the housing inwardly into the central passage and which functions: (i) during wrapping, to engage the balloon member and be displaced by the balloon membrane to provide predetermined pressure onto the balloon membrane as the wrapping apparatus is rotated relative to the balloon catheter to wrap the balloon membrane about the stylet yet, (ii) after a predetermined degree of wrapping, to allow the balloon membrane to rotate relatively freely within the wrapping apparatus.
Claim 45
Independent Claim
214 words
An apparatus for wrapping an intra-aortic balloon catheter having a catheter tube sealidly attached to a balloon membrane to permit fluidic communication therebetween and a stylet passing through the balloon membrane and at least into the catheter tube, comprising: (a) a housing having: (i) an upper portion with a channel; and (ii) a lower portion with a channel; said upper portion and lower portions being releasably secured together so that the channels form a central passage and at least one side passage, the central passage being located and configured to receive and surround the stylet and a portion of the balloon membrane and the side passage being located and configured to received and surround another portion of the balloon membrane; and (b) displaceable clutching means which includes at least two flexible vanes projecting respectively from the upper and lower portions of the housing inwardly into the central passage and which functions: (i) during wrapping, to engage the balloon member and be displaced by the balloon membrane to provide predetermined pressure onto the balloon membrane as the wrapping apparatus is rotated relative to the balloon catheter to wrap the balloon membrane about the stylet yet, (ii) after a predetermined degree of wrapping, to allow the balloon membrane to rotate relatively freely within the wrapping apparatus.
Claim 46
Independent Claim
234 words
A method for wrapping a balloon catheter having a catheter tube sealidly attached to a balloon membrane to permit fluidic communication therebetween and a stylet passing through the balloon membrane and at least into the catheter tube, the method comprising: (a) evacuating gas from the balloon catheter so as to collapse the balloon membrane around the stylet; (b) inserting the balloon membrane into a wrapping apparatus having: (i) a housing with a central and at least one side passage; and (ii) flexible vane means projecting from the housing inwardly into the central passage for engaging the balloon membrane, being displaced by the wrapping balloon membrane and exerting predetermined pressure on the balloon membrane, said balloon membrane being inserted into the wrapping apparatus such that at least one side passage surrounds a portion of the balloon membrane and the central passage surrounds a portion of the balloon membrane about the stylet; (c) rotating the wrapping apparatus relative to the balloon catheter so as to wrap the balloon membrane about the stylet; and (d) by the vane means, (i) during wrapping, engaging the balloon membrane, and exerting a predetermined pressure on the balloon membrane as the wrapping apparatus is rotated relative thereto, said vane means being displaced by the wrapping balloon membrane, yet, (ii) after the balloon membrane has achieved a predetermined degree of wrapping, permitting relatively free rotation of the balloon membrane within the housing.
Claim 47
Independent Claim
234 words
A method for wrapping a balloon catheter having a catheter tube sealidly attached to a balloon membrane to permit fluidic communication therebetween and a stylet passing through the balloon membrane and at least into the catheter tube, the method comprising: (a) evacuating gas from the balloon catheter so as to collapse the balloon membrane around the stylet; (b) inserting the balloon membrane into a wrapping apparatus having: (i) a housing with a central and at least one side passage; and (ii) flexible vane means projecting from the housing inwardly into the central passage for engaging the balloon membrane, being displaced by the wrapping balloon membrane and exerting predetermined pressure on the balloon membrane, said balloon membrane being inserted into the wrapping apparatus such that at least one side passage surrounds a portion of the balloon membrane and the central passage surrounds a portion of the balloon membrane about the stylet; (c) rotating the wrapping apparatus relative to the balloon catheter so as to wrap the balloon membrane about the stylet; and (d) by the vane means, (i) during wrapping, engaging the balloon membrane, and exerting a predetermined pressure on the balloon membrane as the wrapping apparatus is rotated relative thereto, said vane means being displaced by the wrapping balloon membrane, yet, (ii) after the balloon membrane has achieved a predetermined degree of wrapping, permitting relatively free rotation of the balloon membrane within the housing.