1. A head restraint for a vehicle seat, wherein the head restraint operates favorably in response to an event of predetermined magnitude, and the head restraint comprises:
a first subassembly;
a second subassembly mounted for moving forward relative to the first subassembly;
a drive mounted for moving the second subassembly forward relative to the first subassembly; and
a locking unit operative for having:
a locked state prior to the event of predetermined magnitude, wherein in the locked state the locking unit prevents the drive from moving the second subassembly forward relative to the first subassembly, and
an unlocked state in response to the event of predetermined magnitude, wherein in the unlocked state the locking unit does not prevent the drive from moving the second subassembly forward relative to the first subassembly, whereby the drive moves the second subassembly forward relative to the first subassembly in response to the event of predetermined magnitude,
wherein the locking unit comprises a magnet arranged so that a magnetic field of the magnet is operative for maintaining the locking unit in the locked state prior to the event of predetermined magnitude.
2. A head restraint according to claim 1, wherein the magnet is a permanent magnet and the locking unit further comprises a coil that is for producing a magnetic field in response to the coil being electrically energized.
3. A head restraint according to claim 2, wherein the coil is arranged so that the magnetic field produced by the coil counteracts the magnetic field of the permanent and thereby causes the locking unit to transition to the unlocked state.
4. A head restraint according to claim 1, wherein:
the magnet is a compound magnet including a permanent magnet and an electromagnet, and
the compound magnet is operative so that energizing the electromagnet results in a weakening of said magnetic field, and the weakening of said magnetic field causes the locking unit to transition to the unlocked state.
5. A head restraint according to claim 4, wherein:
the drive is prebiased for moving the second subassembly forward relative to the first subassembly; and
the electromagnet is deenergized during the locked state, whereby said magnetic field is provided solely by the permanent magnet during the locked state.
6. A head restraint according to claim 1, wherein:
the drive:
is in a first configuration during the locked state,
is in a second configuration as the drive completes the moving of the second subassembly forward relative to the first subassembly, and
is biased toward the second configuration, whereby the drive moves the second subassembly forward relative to the first subassembly during the unlocked state; and
the locking unit further comprises a retaining means for being acted upon by the magnetic field of the magnet and thereby retaining the drive in the first configuration during the locked state.
7. A head restraint according to claim 6, wherein the retaining means is further for releasing the drive in the unlocked state, whereby the drive transitions from the first configuration to the second configuration and thereby moves the second subassembly forward relative to the first subassembly.
8. A head restraint according to claim 6, wherein the retaining means comprises pivotable, spring-loaded components.
9. A head restraint according to claim 6, wherein:
the drive comprises a spring; and
the retaining means comprises:
a catch that is mounted for moving between open and closed configurations, wherein the catch is biased toward the open configuration, and the catch at least indirectly secures the drive while the catch is in the closed configuration during the locked state, and
a retaining element for retaining the catch in the closed configuration during the locked state, wherein the retaining element is an intercepting element or a retaining spring.
10. A head restraint according to claim 9, wherein the retaining element is the intercepting element and the intercepting element retains the catch in the open configuration during the unlocked state.
11. A head restraint according to claim 6, wherein the retaining means comprises a plate that is attracted to the magnet due to the magnetic field, and the plate is mounted so that:
the plate is proximate the magnet during the locked state, and
the plate carries out a tilting or pivoting movement while the locking unit transitions from the locked state to the unlocked state.
12. A head restraint according to claim 11, wherein:
the retaining means further comprises:
a catch that is mounted for moving between open and closed configurations, wherein the catch is biased toward the open configuration, and the catch at least indirectly secures the drive while the catch is in the closed configuration during the locked state, and
a movably mounted retaining element for retaining the catch in the closed configuration during the locked state; and
the clamping plate is connected in an articulated manner to the retaining element.
13. A head restraint according to claim 11, wherein:
the retaining means further comprises:
a catch that is mounted for moving between open and closed configurations, wherein the catch is biased toward the open configuration, and the catch at least indirectly secures the drive while the catch is in the closed configuration during the locked state, and
a release means for holding the catch in the closed configuration and releasing the catch so that the catch moves from the closed configuration to the open configuration; and
the plate is connected to the release means.
14. A head restraint for a vehicle seat, wherein the head restraint operates favorably in response to an event of predetermined magnitude, and the head restraint comprises:
a first subassembly;
a second subassembly mounted for moving forward relative to the first subassembly;
a drive mounted for moving the second subassembly forward relative to the first subassembly, wherein the drive is in a first configuration prior to the moving of the second subassembly forward relative to the first subassembly, the drive is in a second configuration as the drive completes the moving of the second subassembly forward relative to the first subassembly, and the drive is biased toward the second configuration; and
a locking unit operative for having:
a locked state prior to the event of predetermined magnitude, wherein the locking unit prevents the drive from transitioning from the first configuration to the second configuration while the locking unit is in the locked state, and
an unlocked state in response to the event of predetermined magnitude, wherein the locking unit does not prevent the drive from transitioning from the first configuration to the second configuration while the locking unit is in the unlocked state, whereby the drive moves the second subassembly forward relative to the first subassembly during the unlocked state,
wherein the locking unit includes:
a magnet, and
a retaining means for functioning so that the magnet operates via the retaining means to maintain the locking unit in the locked state.
15. A head restraint according to claim 14, wherein the retaining means is further for releasing the drive in the unlocked state, whereby the drive transitions from the first configuration to the second configuration and thereby moves the second subassembly forward relative to the first subassembly.
16. A head restraint according to claim 15, wherein the retaining means comprises pivotable, spring-loaded components.
17. A head restraint according to claim 14, wherein:
the drive comprises a spring; and
the retaining means comprises:
a catch that is mounted for moving between open and closed configurations, wherein the catch is biased toward the open configuration, and the catch at least indirectly secures the drive while the catch is in the closed configuration during the locked state, and
a retaining element for retaining the catch in the closed configuration during the locked state, wherein the retaining element is an intercepting element or a retaining spring.
18. A head restraint according to claim 17, wherein the retaining element is the intercepting element and the intercepting element retains the catch in the open configuration during the unlocked state.
19. A head restraint according to claim 14, wherein the retaining means comprises a plate that is attracted to the magnet, and the plate is mounted so that:
the plate is proximate the magnet during the locked state, and
the plate carries out a tilting or pivoting movement while the locking unit transitions from the locked state to the unlocked state.
20. A head restraint according to claim 19, wherein:
the retaining means further comprises:
a catch that is mounted for moving between open and closed configurations, wherein the catch is biased toward the open configuration, and the catch at least indirectly secures the drive while the catch is in the closed configuration during the locked state, and
a movably mounted retaining element for retaining the catch in the closed configuration during the locked state; and
the clamping plate is connected in an articulated manner to the retaining element.
21. A head restraint according to claim 19, wherein:
the retaining means further comprises:
a catch that is mounted for moving between open and closed configurations, wherein the catch is biased toward the open configuration, and the catch at least indirectly secures the drive while the catch is in the closed configuration during the locked state, and
a release means for holding the catch in the closed configuration and releasing the catch so that the catch moves from the closed configuration to the open configuration; and
the plate is connected to the release means.
22. A method of operating a head restraint having a first subassembly, a second subassembly mounted for moving forward relative to the first subassembly, and a drive mounted for moving the second subassembly forward relative to the first subassembly, the method comprising:
using a magnetic field to prevent the drive from moving the second subassembly forward relative to the first subassembly prior to an event of predetermined magnitude.
23. A method according to claim 22, wherein the magnetic field is a first magnetic field, and the method further comprises counteracting the first magnetic field with a second magnetic field to thereby enable the drive to move the second subassembly forward relative to the first subassembly, with the counteracting being responsive to the event of predetermined magnitude.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A piezoelectric element comprising:
a first non-extendible and non-contractible portion which neither extend nor contract, the first non-extendible and non-contractible portion being provided at one end of the piezoelectric element;
an extendible and contractible portion which extends and contracts;
a plurality of electrodes which are provided on a surface of the extendible and contractible portion and are provided so as to extend to a position where a surface of the first non-extendible and non-contractible portion lies;
a plurality of connecting terminals which are connected to said plurality of electrodes and are provided in a position where the first non-extendible and non-contractible portion lies; and
a flexible printed wiring substrate positioned to be adjacent to a back end surface of said first non-extendible and non-contractible portion, wherein
said plurality of connecting terminals are connected to the flexible printed wiring substrate.
2. The piezoelectric element as set forth in claim 1,
wherein said at least one electrode comprises two electrodes provided in such a way as to sandwich the extendible and contractible portion, and
said at least one connecting terminal comprises two connecting terminals that are provided to be connected to the two electrodes, respectively, and are both provided on a side of the one end of the piezoelectric element where the first non-extendible and non-contractible portion lies.
3. A driving apparatus comprising:
a piezoelectric element;
a driving shaft that reciprocates in response to an extension and contraction of the piezoelectric element; and
a driven member, frictionally engaged with the driving shaft, that moves along the driving shaft by reciprocating the driving shaft,
wherein the piezoelectric element comprises:
a first non-extendible and non-contractible portion which neither extend nor contract, the first non-extendible and non-contractible portion being provided at one end of the piezoelectric element;
an extendible and contractible portion which extends and contracts;
a plurality of electrodes which are provided on a surface of the extendible and contractible portion and are provided so as to extend to a position where a surface of the first non-extendible and non-contractible portion lies;
a plurality of connecting terminals which are connected to said plurality of electrodes and are provided in a position where the first non-extendible and non-contractible portion lies; and
a flexible printed wiring substrate positioned to be adjacent to a back end surface of said first non-extendible and non-contractible portion, wherein
said plurality of connecting terminals are connected to the flexible printed wiring substrate.
4. The driving apparatus as set forth in claim 3,
wherein said at least one electrode comprises two electrodes provided in such a way as to sandwich the extendible and contractible portion, and
said at least one connecting terminal comprises two connecting terminals that are provided to be connected to the two electrodes, respectively, and are both provided on a side of the one end of the piezoelectric element where the first non-extendible and non-contractible portion lies.
5. The driving apparatus as set forth in claim 3,
wherein the driving shaft is attached to the other end of the piezoelectric element, and
the driving apparatus further comprises a wiring member, attached to the one end of the piezoelectric element, that is to be connected to said at least one connecting terminal.
6. The driving apparatus as set forth in claim 5,
wherein the piezoelectric element further comprises a second non-extendible and non-contractible portion provided at the other end of the piezoelectric element,
the one end of the piezoelectric element to which the wiring member is attached is made to constitute a free end, and
the first non-extendible and non-contractible portion become heavier than the second non-extendible and non-contractible portion.
7. The driving apparatus as set forth in claim 3, wherein
each of the plurality of connecting terminals has a first leg and a second leg formed in an L-shape with the first leg of each being formed on an unsupported free end surface of said first non-extendible and non-contractible portion at the unsupported free end of the piezoelectric element adjacent to and connected with the flexible printed wiring substrate positioned thereat and with the second leg of each being electrically connected to a corresponding connection part of a corresponding electrode.
8. The driving apparatus as set forth in claim 3, wherein
two connecting terminals are provided and each has a first leg and a second leg formed in an L-shape with the first leg of each being formed on an unsupported free end surface of said first non-extendible and non-contractible portion at the unsupported free end of the piezoelectric element adjacent to and connected with the flexible printed wiring substrate positioned thereat and with the second leg of each being electrically connected to a corresponding connection part of a corresponding electrode.
9. The piezoelectric element as set forth in claim 1,
wherein each of said plurality of connecting terminals has an L-shape and is positioned at a respective corner of said first non-extendible and non-contractible portion that is formed between a respective side surface of said first non-extendible and non-contractible portion and said back end surface, and
one leg of each L-shaped connecting terminal extends from said respective corner along said respective side surface to provide electrical contact with a corresponding one of the plurality of electrodes along said respective side surface and a second leg of the L-shaped connecting terminal extends from said respective corner along said back end surface to provide electrical contact with the flexible printed wiring substrate along said back end surface.
10. The piezoelectric element as set forth in claim 1,
wherein said plurality of electrodes comprises two electrodes provided in such a way as to sandwich the extendible and contractible portion and to extend to a first side surface and a second side surface on an opposite side of said first non-extendible and non-contractible portion, and
said plurality of connecting terminals comprises two connecting terminals that both have an L-shape and are separately provided to be at opposite side corners formed between said back end surface and each of said first side surface and said second side surface so that said one leg of each of said L-shaped connecting terminals extends from each said corner along each corresponding one of said first side surface and second side surface to make electrical contact with a corresponding one of the two connecting electrodes along that corresponding side surface and said second leg of each of said L-shaped connecting terminals extends from each said corner along said back end surface to provide electrical contact with the flexible printed wiring substrate along said back end surface.
11. The driving apparatus as set forth in claim 3, wherein
the first non-extendible and non-contractible portion is provided at an unsupported free end of the piezoelectric element,
the extendible and contractible portion extends and contracts to provide the extension and contraction of the piezoelectric element, the extendible and contractible portion is formed as a middle portion of the piezoelectric element between the first non-extendible and non-contractible portion at the unsupported free end side of the piezoelectric element and a second non-extendible and non-contractible portion that cannot extend or contract that is provided at a second end of the piezoelectric element coupled to the driving shaft so as to couple said expansion and contraction of the extendible and contractible portion to the driving shaft,
the plurality of electrodes are provided on respective side surfaces of the extendible and contractible portion and are provided so as to extend so that at least a part of the respective side surface of the first non-extendible and non-contractible portion lies under a connection part of the plurality of electrodes, and
the first non-extendible and non-contractible portion is provided so as to be heavier than the second non-extendible and non-contractible portion so that the first non-extendible and non-contractible portion provided at the unsupported free end of the piezoelectric element is relatively stationary as compared to the second non-extendible and non-contractible portion that is coupled to the driving shaft and can move so as to couple said expansion and contraction of the extendible and contractible portion to the driving shaft.