JP2023181820A - Seat structure and seat manufacturing method - Google Patents

Abstract

To provide a seat structure which enables easy attachment/detachment of a seating sensor to a seat cushion.SOLUTION: A seat structure includes: a seat cushion 10 in which a sensor recessed part 14 is formed on a seating surface 12; and a seating sensor 20 which is disposed in the sensor recessed part 14 and detects seating of an occupant. The seating sensor 20 includes: a sub pad 22; a sensor bracket 24 which covers the sub pad 22 from above and has one or more anchor parts 34 engaging with the seat cushion 10; and one or more sensor elements 26 which are attached to the sensor bracket 24 and output electric signals generated according to pressure.SELECTED DRAWING: Figure 1

Description

This specification discloses the structure of a seat provided with a seating sensor that detects whether a person is sitting, and a method for manufacturing the seat.

Conventionally, it has been proposed to provide a seat with a seating sensor that detects whether a person is sitting on the seat. Such a seating sensor is usually attached to the seat surface of a seat cushion.

Patent Document 1 discloses such a sheet. Specifically, Patent Document 1 discloses a technique in which a sub-pad made of a foam is bonded to a sensor body, and then the sub-pad is bonded to the seating surface of a seat cushion. In this way, by interposing the sub-pad between the seat cushion and the sensor body, appropriate cushioning properties can be obtained even when a seating sensor is provided.

Japanese Patent Application Publication No. 2001-157620

However, in the technique disclosed in Patent Document 1, the seating sensor is bonded to the seat cushion 10. Therefore, with the technique disclosed in Patent Document 1, the sensor body and subpad, once attached, cannot be easily removed from the seat cushion. As a result, in the technique disclosed in Patent Document 1, when it is desired to replace the seating sensor due to a failure or the like, it is necessary to replace the entire seat cushion, which is wasteful. Further, when disposing of a seat, it is necessary to separate the seats by material, but in Patent Document 1, the seating sensor and the seat cushion cannot be easily separated.

Therefore, this specification discloses a seat structure in which a seating sensor can be easily attached to and detached from a seat cushion, and a method for manufacturing the seat.

The seat structure disclosed in this specification includes a seat cushion in which a sensor recess is formed in the seat surface, and a seating sensor that is disposed in the sensor recess and detects whether a person is seated, and the seating sensor includes: a sub-pad; a sensor bracket that covers the sub-pad from above and has one or more anchor portions that engage with the seat cushion; and a sensor bracket that is attached to the sensor bracket and outputs an electrical signal in response to pressure. It is characterized by comprising the above sensor element.

In this case, one or more assembly slits extending downward are formed in the bottom surface of the sensor recess, and the sensor bracket includes a main portion overlaid on the top surface of the sub-pad, and an end of the main portion. The anchor portion may include a plurality of leg portions that hang down from the portion and are inserted into the assembly slit, each end of which projects outward in the horizontal direction and functions as the anchor portion.

Further, the method for manufacturing a seat disclosed in this specification includes the steps of: placing a sensor bracket to which one or more sensor elements are attached over an upper side of a sub-pad to form a seating sensor; arranging the seating sensor together with the setting jig in a sensor recess formed on the seat surface of the seat cushion in a state where the setting jig is covered with a tool, and then lifting only the setting jig upward and removing it; one or more assembly slits extending downward are formed in the bottom surface of the sensor recess, and the sensor bracket includes a main part overlaid on the top surface of the sub-pad, and an end of the main part. The setting jig has a plurality of leg parts that hang down from the main part and are inserted into the assembly slit, the ends of each of which protrude outward. It has an upper wall that overlaps with the upper side, and a plurality of hanging walls that hang down from an end of the upper wall, and suppresses outward expansion of the leg portion by covering the upper side of the seating sensor. It is characterized by

In this case, the sub-pad may be selectively selected based on the required sensor sensitivity from among a plurality of types of sub-pad candidates that differ from each other in at least one of thickness and hardness.

According to the description disclosed herein, the seating sensor is engaged with the seat cushion without being adhered to the seat cushion. Therefore, the seating sensor can be easily assembled to the seat cushion, and once assembled, the seating sensor can be easily removed without destroying the seat cushion.

FIG. 3 is an exploded perspective view of a seat cushion and a seating sensor. FIG. 3 is a plan view of the vicinity of the seating sensor. It is a perspective view of a sensor bracket. 3 is a sectional view taken along line AA in FIG. 2. FIG. 3 is a sectional view taken along line BB in FIG. 2. FIG. It is a perspective view of a setting jig. FIG. 3 is a cross-sectional view showing how the seating sensor is assembled.

The structure of the sheet will be described below with reference to the drawings. FIG. 1 is an exploded perspective view of the seat cushion 10 and the seating sensor 20. Moreover, FIG. 2 is a plan view of the seating sensor 20 and its surroundings. Note that in the following description, "front", "rear", "upper", "lower", "left", and "right" all indicate the direction seen from the seated person sitting on the seat. Further, "Fr", "Up", and "Rh" in each drawing indicate the front, upper, and right side, respectively, as seen from the seated person.

The seat in this example is a one-person seat mounted in a vehicle. The seat includes a seat cushion 10 that supports the buttocks of the seated person, and a seat back (not shown) that supports the back of the seated person. A seating sensor 20 is attached to the seat surface 12 of the seat cushion 10 to detect whether or not a person is sitting. A sensor recess 14 for accommodating the seating sensor 20 is formed in the seat surface 12 of the seat cushion 10 at a position approximately at the center in the left-right direction and near the rear end. The sensor recess 14 has a substantially rectangular shape that is long in the front-rear direction when viewed from above. The bottom surface of the sensor recess 14 is a flat surface without unevenness. An assembly slit 16 is formed in the bottom of the sensor recess 14 and extends downward along both left and right edges and the front edge of the bottom. The thick line in FIG. 1 indicates the location where the assembly slit 16 is formed. The assembly slit 16 is used to attach a sensor bracket 24, which will be described later, and will be described later. A cable groove 29 for accommodating a signal cable 28, which will be described later, extends on the rear side of the sensor recess 14. The end of this cable groove 29 is connected to a through hole 18 that vertically passes through the seat cushion 10.

The seating sensor 20 can be roughly divided into a sensor bracket 24 and a sub pad 22. The sub pad 22 is a flat member made of a material having appropriate cushioning properties, for example, a foam such as urethane foam. This sub-pad 22 has a size such that its entirety can fit into the sensor recess 14 . In this example, the sensor sensitivity of the seating sensor 20 is adjusted by adjusting at least one of the thickness and hardness of the sub-pad 22, which will be described later.

The sensor bracket 24 is a sheet metal member that is placed over the sub pad 22. FIG. 3 is a perspective view of the sensor bracket 24. As shown in FIG. 3, a plurality of (four in the illustrated example) sensor elements 26 are attached to the upper surface of the sensor bracket 24. The plurality of sensor elements 26 are arranged in a line with intervals in the front-rear direction. When the sensor element 26 receives pressure, it outputs an electrical signal according to the pressure. The sensor element 26 includes, for example, a pressure sensitive element such as a piezo element.

The sensor bracket 24 has a main portion 30 that overlaps the sub-pad 22 and a plurality of legs 32 that hang down from the end of the main portion 30. In this example, the main portion 30 has a center plate 30a extending in the front-rear direction, and four horizontal plates 30b extending in the left-right direction across the center plate 30a, and has a structure similar to a fish bone as a whole. It has a shape. The sensor element 26 is fixed to the upper surface of the center plate 30a. Note that the shape of the main portion 30 mentioned here is just an example, and other shapes (for example, a rectangular flat shape in a plan view) may be used as long as the size can cover the entire sub pad 22.

The leg portion 32 includes a plurality of horizontal leg portions 32s extending from the end of the horizontal plate 30b, and one front leg portion 32f extending from the front end of the center plate 30a. Each leg 32 extends downward from the end of the main portion 30. However, in an unloaded state where no external force is applied, the leg portions 32 extend diagonally downward, moving outward in the horizontal direction as they move downward, rather than directly downward. In other words, in the no-load state, the angle α between the main portion 30 and the leg portions 32 is greater than 90 degrees. The leg portions 32 have appropriate elasticity, and when subjected to horizontal inward force, the leg portions 32 swing around their bases (i.e., the connecting portions with the main portion 30). The angle α formed with the main portion 30 is reduced.

The vertical dimension of the leg portion 32 is larger than the thickness of the sub pad 22. Therefore, when the sensor bracket 24 is placed over the sub-pad 22, the lower portions of the legs 32 protrude below the bottom surface of the sub-pad 22. The ends of the leg portions 32 are bent horizontally outward in a substantially L-shape. This bent portion functions as an anchor portion 34 that engages with a portion of the seat cushion 10. Further, a positioning hole 38, which is a through hole 18, is formed in the bent portion of the front leg portion 32f. This positioning hole 38 is used for positioning the setting jig 40, which will be described later.

A signal cable 28 such as a flat cable is connected to the rear end of the main portion 30. After the signal cable 28 is arranged along the cable groove 29, it is finally passed through the through hole 18 and pulled out from the underside of the seat cushion 10.

The seating sensor 20 as described above is accommodated in the sensor recess 14, as described repeatedly. 4 and 5 are cross-sectional views showing the seating sensor 20 accommodated in the sensor recess 14, FIG. 4 is a cross-sectional view taken along line AA in FIG. 2, and FIG. 5 is a cross-sectional view taken along line B in FIG. -B sectional view.

As is clear from FIGS. 4 and 5, according to this example, the sub pad 22 is interposed between the sensor element 26 and the seat cushion 10. In this example, the sensor sensitivity of the seating sensor 20 is adjusted by adjusting at least one of the thickness and hardness of the sub-pad 22.

That is, the sensor sensitivity required for the seating sensor 20 differs depending on the type of seat. In order to correspond to different sensor sensitivities for each sheet, it is possible to adjust the sensor element 26 itself, but in this case, it is necessary to prepare many types of sensor elements 26 and, by extension, many types of sensor brackets 24. This results in an increase in the number of types of parts and, in turn, an increase in the manufacturing cost of the seat. Therefore, in this example, the sensor sensitivity is changed by changing the type of sub pad 22 interposed between the sensor element 26 and the seat cushion 10 without changing the sensor element 26 itself. Specifically, a plurality of types of sub pads 22 (hereinafter referred to as "sub pad candidates") having at least one of thickness and height different from each other are prepared in advance. Then, the operator selects a sub-pad 22 suitable for the required sensor sensitivity from among the plurality of types of sub-pad candidates, and combines this with the sensor bracket 24. Note that if it is desired to increase the sensor sensitivity, the thickness of the sub-pad 22 may be increased or the sub-pad 22 may be made hard.

By arranging the sub pad 22 between the sensor bracket 24 and the seat cushion 10 in this manner, the sensitivity of the seating sensor 20 can be adjusted without increasing the types of sensor elements 26. In addition, in the case of this example, it is necessary to prepare multiple types of sub pads 22, but since the sub pads 22 can be prepared at a lower cost than the sensor elements 26, according to this example, multiple types of sensor elements 26 are prepared. The cost can be significantly reduced compared to the case where Furthermore, at the stage of prototyping the sheet, it is necessary to evaluate the sensor sensitivity while changing it. According to this example, the sensor sensitivity can be changed by changing the sub pad 22. In other words, since there is no need to change the electrical configuration when changing the sensor sensitivity, the effort required for evaluating sheet prototypes can be reduced. As a result, the effort and cost required for sheet trial production can be reduced. Further, according to this example, the sub-pad 22 can absorb the influence that the difference in hardness of the cushioning material of the seat cushion 10 has on the sensor sensitivity. Therefore, the seat cushion 10 can be designed independently of the seating sensor 20, and the degree of freedom in designing the seat cushion 10 is improved.

The seating sensor 20 is prevented from detaching from the seat cushion 10 by the anchor portion 34 biting into the seat cushion 10. That is, as shown in FIGS. 4 and 5, an assembly slit 16 extending downward is formed at a corner of the bottom surface of the sensor recess 14. The seating sensor 20 is placed in the sensor recess 14 with the sensor bracket 24 placed over the sub pad 22 . At this time, the lower portions of the legs 32 of the sensor bracket 24 protrude below the bottom surface of the sub pad 22 and are inserted into the assembly slits 16. The anchor portion 34 provided at the end of the leg portion 32 bites into the seat cushion 10 and is engaged with the seat cushion 10 inside the assembly slit 16. This biting of the anchor portion 34 prevents the sensor bracket 24 and, by extension, the sub pad 22 from detaching from the sensor recess 14.

In order to facilitate the assembly work of the seating sensor 20, a setting jig 40 is used in this example. FIG. 6 is a perspective view of the setting jig 40. The setting jig 40 has an upper wall 42 that overlaps the main portion 30 and a plurality of hanging walls 44 that hang down from the end of the upper wall 42. The hanging wall 44 includes a pair of horizontal hanging walls 44s extending downward from both left and right ends of the upper wall 42, and one front hanging wall 44f extending downward from the front end of the upper wall 42. Therefore, the setting jig 40 is a sheet metal member whose bottom surface and rear end surface are open, and whose top surface, left and right side surfaces, and front end surface are covered with walls 44s and 44f.

The upper wall 42 has a size that is approximately the same as or slightly larger than the main portion 30 of the sensor bracket 24 . The hanging walls 44 extend directly below from the ends of the upper walls 42, and the angle between each hanging wall 44 and the upper wall 42 is approximately 90 degrees. This hanging wall 44 has approximately the same height as the leg portion 32 of the sensor bracket 24. Further, the hanging wall 44 has higher rigidity than the leg portion 32, and maintains its posture without deforming even if it comes into contact with the hanging wall 44. Therefore, when the setting jig 40 is placed on the sensor bracket 24, the hanging wall 44 maintains a posture facing straight down, and the posture of the leg portion 32 is corrected by the hanging wall 44. Specifically, the leg portion 32 has its end (that is, the anchor portion 34) moved inward in the horizontal direction along the hanging wall 44.

At the center of the lower end of the front hanging wall 44f, there is a positioning projection 46 that projects downward. This positioning protrusion 46 is a portion that is inserted into the positioning hole 38 of the front leg portion 32f when the setting jig 40 is placed on the seating sensor 20. By inserting the positioning protrusion 46 into the positioning hole 38, the position of the setting jig 40 with respect to the seating sensor 20 is defined.

When assembling the seating sensor 20 to the seat cushion 10, the operator first selects the subpad 22 suitable for the required sensor sensitivity from among multiple types of subpad candidates. Next, the operator places the sensor bracket 24 over the selected sub-pad 22. At this time, the sensor bracket 24 may be simply overlapped with the sub-pad 22, or may be temporarily adhered to the sub-pad 22 using adhesive, double-sided tape, or the like. When the sensor bracket 24 is temporarily bonded to the sub pad 22, the assembling work is facilitated because both 22 and 24 are prevented from being separated against one's will during the assembling work. Further, by temporarily bonding the two parts 22 and 24 with a force so weak that they can be easily separated, the separation work when disposing of the seating sensor 20, that is, the work of separating the sensor bracket 24 and the sub pad 22, becomes easy.

If the seating sensor 20 can be constructed by combining the sub pad 22 and the sensor bracket 24, the operator then places the setting jig 40 over the seating sensor 20. In the process of covering the setting jig 40, the hanging wall 44 of the setting jig 40 comes into contact with the leg part 32 of the sensor bracket 24, and presses the leg part 32 inward in the horizontal direction. In response to this pressure, the leg portion 32 swings so that its distal end faces inward in the horizontal direction. Finally, the leg portion 32 is corrected to a posture extending directly downward, similar to the hanging wall 44.

In this state, the operator places the seating sensor 20 together with the setting jig 40 in the sensor recess 14 . At this time, the leg portion 32 and the hanging wall 44 are inserted into the assembly slit 16. FIG. 7 is a sectional view showing the state of this assembly work. As shown in FIG. 7, the leg portion 32 is inserted into the assembly slit 16 while being restrained from expanding outward in the horizontal direction by the hanging wall 44. When the sub pad 22 finally comes into contact with the bottom surface of the sensor recess 14 , the operator lifts only the setting jig 40 and removes the setting jig 40 from the sensor recess 14 .

When the setting jig 40 is removed, the leg portions 32 swing so that their ends (anchor portions 34) move outward in the horizontal direction due to the elastic restoring force. Due to this swinging, the anchor portions 34 of the leg portions 32 bite into and engage with the cushioning material that constitutes the seat cushion 10. Thereby, the assembly of the seating sensor 20 is completed. After the seating sensor 20 is assembled, the seat cushion 10 is covered with a seat cover (not shown) made of cloth or leather.

As is clear from the above description, in this example, while the seating sensor 20 is engaged with the seat cushion 10, the seating sensor 20 is not bonded to the seat cushion 10. Therefore, according to this example, the seating sensor 20, once assembled, can be removed from the seat cushion 10 without destroying the seat cushion 10. As a result, the cost required for replacing the seating sensor 20 can be reduced, and the sorting work at the time of disposal can be simplified.

For example, consider a case where the seating sensor 20 has failed and needs to be replaced. If the seating sensor 20 is adhered to the seat cushion 10, it is not possible to take out only the seating sensor 20 without destroying the seat cushion 10. Therefore, in this case, it is necessary to replace the seating sensor 20 together with the seat cushion 10, and the cost required to replace the seating sensor 20 becomes extremely high.

On the other hand, in the case of a configuration in which the seating sensor 20 is not bonded to the seat cushion 10 as in this example, the seating sensor 20 can be taken out without destroying the seat cushion 10. Specifically, when the operator wants to remove the seating sensor 20, the operator places the setting jig 40 over the seating sensor 20 assembled to the seat cushion 10. By covering with the setting jig 40, the spread of the leg portions 32 is suppressed, and the digging of the anchor portion 34 into the seat cushion 10 is alleviated. In this state, the operator lifts the sensor bracket 24 upward together with the setting jig 40. At this time, since the anchor portion 34 is less likely to bite, the sensor bracket 24 can be lifted upward without applying a large load to the seat cushion 10. As a result, only the seating sensor 20 can be taken out without destroying the seat cushion 10, and the cost required for replacing the seating sensor 20 can be significantly reduced. Further, in this example, since the seating sensor 20 is not bonded to the seat cushion 10, when the seat cushion 10 is discarded, the seat cushion 10 and the seating sensor 20 can be easily separated, and the separation work can be simplified.

Note that this seat structure is only an example, and as long as the seating sensor 20 has the sensor bracket 24 and the sub pad 22, and the sensor bracket 24 has the anchor portion 34 that engages with the seat cushion 10, other seat structures may be used. The configuration may be changed. For example, in this example, the subpad 22 is constructed from a single pad member, but the subpad 22 may be constructed by laminating two or more pad members. Further, the shape of the sensor bracket 24 may also be changed as appropriate. For example, the number and shape of the legs 32 may be changed. Further, in this example, the anchor portion 34 is formed by bending the end of the leg portion 32, but the anchor portion 34 may have another shape as long as it can be engaged with the seat cushion 10. For example, the anchor portion 34 may be an inverted triangular protrusion that protrudes outward in the horizontal direction at the end of the leg portion 32. Further, the upper surfaces of the sub pad 22 and the sensor bracket 24 may be curved surfaces that are gently curved to match the shape of the buttocks of the seated person. Furthermore, although this example has been explained using a one-person vehicle seat as an example, the technology disclosed in this specification can be applied to other types of seats, such as bench seats on which multiple people can sit at the same time. Good too.

10 Seat cushion, 12 Seat surface, 14 Sensor recess, 16 Assembly slit, 18 Through hole, 20 Seating sensor, 22 Sub pad, 24 Sensor bracket, 26 Sensor element, 28 Signal cable, 29 Cable groove, 30 Main part, 30a Center plate, 30b horizontal plate, 32 leg, 34 anchor, 38 positioning hole, 40 setting jig, 42 upper wall, 44 hanging wall, 46 positioning protrusion.

Claims (4)

A seat cushion with a sensor recess formed on the seat surface;
a seating sensor that is arranged in the sensor recess and detects whether a person is sitting;
The seating sensor comprises:
sub pad and
a sensor bracket that covers the sub-pad from above and has one or more anchor portions that engage with the seat cushion;
one or more sensor elements attached to the sensor bracket and outputting electrical signals according to pressure;
A seat structure characterized by comprising. The sheet structure according to claim 1,
One or more assembly slits extending downward are formed on the bottom surface of the sensor recess, and
The sensor bracket is
a main portion overlaid on the top surface of the sub-pad;
a plurality of leg parts hanging from an end of the main part and inserted into the assembly slit, each end of which projects horizontally outward and functions as the anchor part;
A sheet structure characterized by having. A sheet manufacturing method, comprising:
placing a sensor bracket, to which one or more sensor elements are attached, over the subpad to form a seating sensor;
With the setting jig placed above the seating sensor, the seating sensor together with the setting jig is placed in the sensor recess formed on the seat surface of the seat cushion, and then only the setting jig is placed on the upper side. a step of lifting and separating;
one or more assembly slits extending downward are formed on the bottom surface of the sensor recess,
The sensor bracket is
a main portion overlaid on the top surface of the sub-pad;
a plurality of leg parts hanging from an end of the main part and inserted into the assembly slit, the plurality of leg parts each having an end protruding outward;
The setting jig has an upper wall overlapping the main part and a plurality of hanging walls hanging from an end of the upper wall, and the setting jig has a plurality of hanging walls that are placed over the seating sensor. suppressing outward expansion of the legs;
A sheet manufacturing method characterized by: The sheet manufacturing method according to claim 3,
The sheet manufacturing method is characterized in that the sub-pad is selectively selected based on required sensor sensitivity from among a plurality of types of sub-pad candidates that differ from each other in at least one of thickness and hardness.

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