Temperature Sensor Assembly

Abstract

To reduce the size of a temperature sensor.SOLUTION: A temperature sensor 7 is used for detection of the cell temperature of an automotive battery, and is assembled to a case 2 to constitute a busbar module 1. The temperature sensor 7 comprises an FPC 3, a chip thermistor 4 mounted on the surface of the FPC 3, a metal heat-receiving component 5 that comes into contact with a top face 9 of the battery cell, and an elastic member 6 assembled to the heat-receiving component 5. The case 2 includes an opposed wall 20 facing a cell top surface 9, and upright walls 22, 23 extending from the opposed wall 20 toward a plate part 62 of the elastic member 6. The elastic member 6 is used to press the heat-receiving component 5 so that the heat-receiving component 5 is brought into contact with the top face 9 of the battery cell with appropriate pressure, and is composed of rubber material. The elastic member 6 includes a press-fit engagement part 61 which is pressed into a holding hole 21 of the opposed wall 20, a plate part 62 having the FPC 3 between the heat-receiving component 5 and itself, and an intermediate part 63.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a temperature sensor assembly in which a temperature sensor used for detecting the temperature of a cell of an in-vehicle battery is assembled in a case. [Background technology]

[0002] Batteries installed in hybrid and electric vehicles are configured with multiple battery cells connected in series to obtain high voltage. In order to prevent overcharging and over-discharging of such batteries, temperature sensors are attached to the battery cells to monitor the temperature (see Patent Document 1).

[0003] An example of the above-mentioned temperature sensor is shown in Fig. 9. This temperature sensor 500 includes an FPC 503 on which a thermistor 504 is mounted, a metal heat-receiving part 505 that surrounds the thermistor 504 and is in contact with the upper surface of the battery cell, and a resin part 506 attached to the heat-receiving part 505. The resin part 506 includes a pair of locking spring parts 561 that lock onto a case attached to the upper surface of the battery.

[0004] In such a temperature sensor 500, the heat receiving component 505 comes into contact with the upper surface of the battery cell with an appropriate pressure due to the spring properties of the pair of locking spring parts 561 that are locked to the case. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2011-17638 A Summary of the Invention [Problem to be solved by the invention]

[0006] In a temperature sensor assembly in which the above-mentioned temperature sensor 500 is assembled in a case, there is a demand for reducing the mounting space in the case for the temperature sensor, that is, for the temperature sensor to be miniaturized, and there is room for improvement.

[0007] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to reduce the size of a temperature sensor. [Means for solving the problem]

[0008] The temperature sensor assembly of the present invention comprises a temperature sensor and a case that is attached to a part to be measured while holding the temperature sensor, the case having an opposing wall facing the part to be measured, and a holding hole for the temperature sensor formed in the opposing wall, the temperature sensor comprising a flexible printed circuit board, a chip thermistor surface-mounted on the flexible printed circuit board, a metal heat-receiving component in contact with the part to be measured, and an elastic member assembled to the heat-receiving component, the elastic member comprising a press-fit engagement portion pressed into the holding hole, a plate portion that sandwiches the flexible printed circuit board between the heat-receiving component, and an intermediate portion between the press-fit engagement portion and the plate portion, and the case having a vertical wall extending from the opposing wall toward the plate portion. Effect of the Invention

[0009] According to the present invention, the temperature sensor can be made smaller, and the space required for mounting the temperature sensor in the case can be reduced. [Brief description of the drawings]

[0010] [Figure 1] 1 is a perspective view of a temperature sensor assembly according to an embodiment of the present invention; [Diagram 2] FIG. 2 is a cross-sectional view taken along the line AA in FIG. [Diagram 3] FIG. 2 is a front view of the temperature sensor of FIG. [Figure 4] FIG. 4 is a cross-sectional view of the temperature sensor of FIG. [Diagram 5]FIG. 2 is a diagram for explaining a method of assembling the temperature sensor assembly of FIG. 1, showing how an elastic member is attached to a case. [Figure 6] 6 is a diagram showing how a heat-receiving component is assembled to the elastic member assembled in the case of FIG. 5. FIG. [Figure 7] 7 is a diagram for explaining the function of the vertical wall of the case when the heat-receiving part is attached to the elastic member in FIG. 6. FIG. [Figure 8] FIG. 2 is a cross-sectional view of a temperature sensor according to a reference example. [Figure 9] FIG. 1 is a front view of a conventional temperature sensor. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] A "temperature sensor assembly" according to one embodiment of the present invention will be described with reference to FIGS.

[0012] Temperature sensor 7 shown in Figures 1 to 4 is used to detect the temperature of a cell of a battery mounted on a hybrid vehicle or an electric vehicle, and is installed on the upper surface 9 of the battery cell (corresponding to the part to be measured temperature) as shown in Figure 2. The battery is configured by connecting a plurality of battery cells in series, and a case 2 made of synthetic resin is attached to the upper surface of the battery.

[0013] Case 2 is fitted with a number of temperature sensors 7 and a number of bus bars in which the electrodes of adjacent battery cells are connected together to connect the battery cells in series. Case 2 fitted with temperature sensors 7 in this manner constitutes a "temperature sensor assembly." In this example, since case 2 is fitted with not only a number of temperature sensors 7 but also a number of bus bars, etc., this is referred to as a "bus bar module" and is given the reference number 1. In other words, bus bar module 1 corresponds to a "temperature sensor assembly."

[0014] The temperature sensor 7 comprises a flexible printed circuit board (hereinafter referred to as FPC) 3, a chip thermistor 4 surface-mounted on the FPC 3, a metal heat-receiving component 5 in contact with the upper surface 9 of the battery cell, and an elastic member 6 assembled to the heat-receiving component 5.

[0015] The FPC 3 is a well-known circuit formed on a flexible thin film. The FPC 3 is formed in a band shape, and a chip thermistor 4 is surface-mounted on one end of the FPC 3. The other end of the FPC 3 is connected to a control unit of the battery. Note that in FIG. 1, the other end of the FPC 3 that extends toward the control unit of the battery (extending to the right in FIG. 1) is not shown.

[0016] The heat-receiving component 5 includes a contact portion 51 that contacts the upper surface 9 of the battery cell, and an attachment portion 52 that is attached to the elastic member 6.

[0017] The contact portion 51 is formed in a rectangular frame shape, and one end of the FPC 3 is sandwiched between the contact portion 51 and a plate portion 62 (described later) of the elastic member 6. In addition, one end of the FPC 3 is joined to the contact portion 51 for mechanical fixation.

[0018] 2 and 6, the mounting portion 52 extends from the outer edge of the contact portion 51 toward a plate portion 62 (described later) of the elastic member 6. The mounting portion 52 is press-fitted into a locking hole 65 formed in the plate portion 62. A retaining projection 52a is formed at the tip of the mounting portion 52 to prevent the mounting portion 52 from coming out of the locking hole 65.

[0019] The elastic member 6 is for pressing the heat-receiving part 5 so that the heat-receiving part 5 comes into contact with the upper surface 9 of the battery cell with an appropriate pressure. Conventional cell temperature sensors perform this pressing using a resin spring or a coil spring, but the temperature sensor 7 of this embodiment uses the elastic member 6 described below for miniaturization.

[0020] 2 to 5, the elastic member 6 includes a press-fit locking portion 61 press-fitted into a holding hole 21 (described later) of the case 2, a plate portion 62 sandwiching one end of the FPC 3 between the press-fit locking portion 61 and the contact portion 51 of the heat-receiving component 5, and an intermediate portion 63 between the press-fit locking portion 61 and the plate portion 62.

[0021] The press-fit locking portion 61 includes a head 61a and a base 61c formed larger than the retaining hole 21, and a constricted portion 61b formed smaller than the retaining hole 21. The base 61c is connected to an intermediate portion 63, the constricted portion 61b is connected to the side of the base 61c opposite the intermediate portion 63, and the head 61a is connected to the side of the constricted portion 61b opposite the base 61c. The press-fit locking portion 61 passes through the retaining hole 21 with the head 61a in an elastically deformed state, and returns to its original shape after passing through, thereby locking into the retaining hole 21 as shown in FIG. 2.

[0022] The plate portion 62 is formed in a rectangular plate shape larger than the outer shape of the contact portion 51. One end of the plate portion 62 is formed with a locking hole 65 into which the attachment portion 52 is press-fitted. The other end of the plate portion 62 is formed with a groove 66 through which the FPC 3 is passed.

[0023] 1 and 2, one end of the FPC 3 is sandwiched between the contact portion 51 and the plate portion 62 with the mounting surface of the chip thermistor 4 in contact with the contact portion 51 and the back surface in contact with the plate portion 62. The chip thermistor 4 is surrounded by the frame-shaped contact portion 51 and faces the upper surface 9 of the battery cell.

[0024] The intermediate portion 63 is formed into a conical shape with the plate portion 62 side being the bottom surface.

[0025] Such elastic member 6 has a pressing function equivalent to that of a resin spring or coil spring of a conventional cell temperature sensor, and achieves a small and low-profile temperature sensor 7. For this reason, the mounting space for temperature sensor 7 in case 2 has a smaller height dimension (the dimension in the opposing direction between opposing wall 20 and battery cell top surface 9) than the conventional product.

[0026] Further, a cavity 64 is provided in the elastic member 6 so as to be out of contact with the portion of the FPC 3 on which the chip thermistor 4 is mounted. In this example, the cavity 64 is provided from the plate portion 62 to the intermediate portion 63.

[0027] 8 does not have a cavity 64 in the elastic member 406. In such a temperature sensor 407, the FPC 3 and elastic member 406 are in constant contact and the chip thermistor 4 is constantly subjected to force, which may cause cracks. In contrast, the temperature sensor 7 of this embodiment has a cavity 64, so no force is applied to the chip thermistor 4 and damage can be prevented.

[0028] The case 2 includes an opposing wall 20 that faces the upper surface 9 of the battery cell, and standing walls 22 and 23 that extend from the opposing wall 20 toward the plate portion 62.

[0029] The opposing wall 20 has a retaining hole 21 in which the press-fit locking portion 61 of the temperature sensor 7 is locked. The retaining hole 21 is a rectangular hole penetrating the opposing wall 20.

[0030] The standing wall 22 is formed in a C-shape on the outer periphery of the retaining hole 21. The standing wall 22 faces the outer periphery of the cavity 64 in the plate portion 62. The standing wall 23 is formed in a straight line. The standing wall 23 faces the portion of the plate portion 62 that is further outward than the locking hole 65.

[0031] 2, with the case 2 attached to the upper surface 9 of the battery cell, a gap H2 is provided between the standing wall 22 and the plate portion 62, and a gap H3 is provided between the standing wall 23 and the plate portion 62. The gaps H2 and H3 are equal. Furthermore, with the case 2 attached to the upper surface 9 of the battery cell, the height dimension H1 of the elastic member 6 in the cavity 64 (the dimension in the direction from the opposing wall 20 toward the plate portion 62) is formed to be larger than the gaps H2 and H3.

[0032] Next, an example of a method for assembling the busbar module 1 will be described. First, as shown in Fig. 5, the press-fit locking portion 61 of the elastic member 6 is press-fitted into the retaining hole 21 of the case 2, and the elastic member 6 is assembled to the case 2. Next, as shown in Fig. 6, the mounting portion 52 of the heat-receiving component 5 to which the FPC 3 is joined is press-fitted into the locking hole 65 of the elastic member 6 assembled to the case 2, and the heat-receiving component 5 is assembled to the elastic member 6. In this manner, a plurality of temperature sensors 7 are assembled to the case 2, and a plurality of bus bars are assembled to the case 2, and the busbar module 1 is assembled.

[0033] As described above, when the heat-receiving component 5 is assembled to the elastic member 6, the elastic member 6 is pressed by the heat-receiving component 5, causing elastic deformation. That is, the elastic member 6 escapes when the heat-receiving component 5 is assembled. If the elastic member 6 escapes, assembly becomes difficult. In this example, as shown in FIG. 7, the vertical walls 22, 23 support the elastic member 6, and the tip surfaces of the vertical walls 22, 23 act as receiving surfaces. This makes it possible to suppress elastic deformation of the elastic member 6 near the locking hole 65, and also to suppress movement of the elastic member 6, making it easier to press the mounting portion 52 into the locking hole 65.

[0034] In FIG. 7, when force is applied to the elastic member 6, the elastic member 6 temporarily elastically deforms and the plate portion 62 abuts against the vertical walls 22, 23. However, after the heat-receiving component 5 is assembled, the elastic deformation is restored and the plate portion 62 is spaced apart from the vertical walls 22, 23.

[0035] Furthermore, when the busbar module 1 is attached to the battery, the busbar module 1 is pressed against the upper surface of the battery, and the elastic member 6 is compressed toward the upper surface. That is, the elastic member 6 strokes toward the upper surface 9. However, since the cavity 64 is provided in the elastic member 6, the elastic member 6 does not come into contact with the portion of the FPC 3 where the chip thermistor 4 is mounted. If the stroke exceeds the expected stroke, the vertical walls 22 and 23 come into contact with the plate portion 62, thereby restricting the elastic member 6 from further stroke. That is, since the height dimension H1 of the cavity 64 is formed to be larger than the intervals H2 and H3 between the vertical walls 22 and 23 and the plate portion 62 as described above, even if the elastic member 6 strokes, it does not come into contact with the portion of the FPC 3, and no force is applied to the chip thermistor 4.

[0036] Furthermore, even when the busbar module 1 is in a battery-mounted state, the standing walls 22, 23 regulate the inclination of the temperature sensor 7. That is, even if some external force is applied after the busbar module 1 is attached, the standing walls 22, 23 regulate the stroke of the elastic member 6 and regulate the inclination of the temperature sensor 7, in the same way as when the busbar module 1 is attached.

[0037] In this way, in the busbar module 1 equipped with the temperature sensor 7, the mounting space for the temperature sensor 7 in the case 2 is smaller than in the conventional product. Also, the cavity 64 and the standing walls 22, 23 are adopted as a structure for preventing damage to the chip thermistor 4. Furthermore, the standing walls 22, 23 function as a structure for facilitating the assembly of the busbar module 1, and also regulate the inclination of the temperature sensor 7 after assembly.

[0038] The above-described embodiment merely shows a typical form of the present invention, and the present invention is not limited to this embodiment. In other words, the present invention can be embodied in various modifications without departing from the gist of the present invention. As long as the configuration of the present invention is still provided even with such modifications, it is of course included in the scope of the present invention. [Explanation of symbols]

[0039] 1 Busbar module (temperature sensor assembly) 2 Cases 3. Flexible Printed Circuit Boards 4 Chip thermistor 5 Heat receiving parts 6 Elastic member 7 Temperature Sensor 9 Top surface of battery cell (temperature measurement part) 20 Facing Wall 22,23 Standing wall 61 Press-fit locking part 62 Board part 63 Middle Section 64 Cavity

Claims

1. A temperature sensor and a case that is attached to a part to be measured while holding the temperature sensor, the case includes a wall facing the temperature measurement portion, and a holding hole for the temperature sensor is formed in the wall; the temperature sensor includes a flexible printed circuit board, a chip thermistor surface-mounted on the flexible printed circuit board, a metal heat-receiving component in contact with the temperature-measured portion, and an elastic member assembled to the heat-receiving component; the elastic member includes a press-fitting engaging portion press-fitted into the holding hole, a plate portion sandwiching the flexible printed circuit board between the heat-receiving component and the plate portion, and an intermediate portion between the press-fitting engaging portion and the plate portion, The case includes a standing wall extending from the opposing wall toward the plate portion. A temperature sensor assembly comprising:

2. the heat receiving component has a contact portion that is in contact with the temperature measurement target portion and an attachment portion that extends from an outer edge of the contact portion toward the plate portion, the flexible printed circuit board being sandwiched between the heat receiving component and the plate portion; The plate portion has a locking hole into which the mounting portion is press-fitted.

2. The temperature sensor assembly of claim 1.

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