JPH0612304B2 - Pressure sensor - Google Patents

Description

Description: TECHNICAL FIELD [0001] The present invention relates to a pressure sensor, and more specifically, a three-way component force that can be detected by decomposing a load acting on a pressure receiving plate into three-direction component forces that are orthogonal to each other. The present invention relates to a pressure sensor in which units of detection pressure-sensitive modules are arranged in an array.

[Prior Art and Problems Thereof] This kind of pressure sensor has been developed for the purpose of obtaining information such as strength of gripping force and surface pressure distribution in the robot hand by detecting the pressure sense. FIG. 7 shows one row of such a pressure sensor, and 1A and 1B are pressure cells vertically held in the groove 3 of the substrate 2. The pressure receiving plate 4 is provided on the upper surfaces of the pressure sensing cells 1A and 1B so as to extend over both sides.
Are provided, and these constitute a pressure sensor module 5 as one unit.

Further, a plurality of strain gauges 6 are formed in the pressure sensing cells 1A and 1B, respectively, as shown in FIG. 8, and the loads acting on the individual pressure receiving plates 4 are decomposed in three directions of F _x , F _y and F _z. Can be detected. That is, the strain gauge 6 is constituted by F _x detecting strain gauge 61, F _y detecting strain gauges 62 and F _z detecting strain gauge 63, one by each of four, is four each of these A Wheatstone bridge circuit (hereinafter referred to as a bridge circuit) is properly assembled between the strain gauges, and a voltage proportional to the component force in the detection direction is output, but not the component force in the other direction. Is obtained.

Therefore, by combining the output voltages from the bridge circuits of such two cells 1A and 1B, the pressure receiving plate 4
The load acting on the can be decomposed into three-direction component forces and detected. The two pressure cells have the following shapes:
Not limited to the octagonal shape as shown in FIG. 7, a ring shape, a special shape as shown in FIG. 9, and other various shapes have already been devised.

However, such a conventional pressure sensor has a problem in terms of strength, and has a relatively high breaking strength with respect to the component force F _{z in the} direction perpendicular to the pressure receiving plate 4, although it has a relatively high breaking strength. Since the breaking strength against the horizontal component forces F _x and F _y along it is low, it was necessary to set the allowable load applied to the pressure receiving plate 4 to a small value.

Furthermore, this type of pressure sensor has a lower load detection sensitivity to the vertical component force F _z than that to the horizontal component forces F _z and F _y , and is broken by simply increasing the thickness of the pressure cells 1A and 1B. When trying to increase the strength, the component force F
_The load detection sensitivity for _z is further reduced and S
This causes problems such as deterioration of / N ratio (signal to noise ratio) and narrowing of the dynamic lens.

Therefore, when the pressure sensor is attached to the pressure detection unit of the robot, the use conditions are inevitably limited, and it is difficult to deal with various tasks required by the robot.

[Object of the Invention] The present invention eliminates the above-mentioned conventional problems, can flexibly cope with various tasks required of a robot, and can supply pressure information. The purpose is to provide.

[Points of the Invention] The present invention configures a pressure sensor module by arranging two pressure cells in parallel between a unit substrate and a pressure plate, and a plurality of pressure sensor modules are distributed on the pressure plate. In a pressure sensor in which loads are decomposed into component forces in three directions orthogonal to each other via pressure cells and arranged so as to be detected, reinforcing bodies are arranged in parallel between two pressure cells, and the reinforcing bodies are connected to each other. It is characterized in that it is adhered to two pressure sensation cells via an adhesive layer capable of absorbing strains generated by component forces in three directions.

Embodiments of the Invention Hereinafter, embodiments of the present invention will be described in detail and specifically with reference to the drawings.

1 and 2 show an embodiment of the present invention, in which 50 is a pressure sensor module. The pressure sensor module 50 is held by the groove 3 of the unit substrate 2, and the pressure cells 1A and 1B are installed upright in parallel.
Reinforcement body 7 interposed in parallel between these cells 1A and 1B
And an adhesive layer 8 for keeping the reinforcing body 7 in this state, and a gap 9 is held between the reinforcing body 7 and the adhesive layer 8 so that the reinforcing body 7 is fixed to the tops of the cells 1A and 1B. And the pressure receiving plate 4.

Here, the reinforcing body 7 is made of a material having an appropriate elastic modulus that does not prevent deformation of the elastic modulus of the cells 1A and 1B, and the adhesive layer 8 further reinforces the cells 1A and 1B. The elastic body is sufficiently lower in elastic modulus than any of the body 7 and has a thickness that can appropriately absorb the stress against horizontal deformation of the cells 1A and 1B. In combination with the action of 7, it is possible to prevent the sensor module 50 from being damaged when the load is detected.

Next how to breaking strength for that horizontal force along the pressure receiving plate 4 without damaging the load detection sensitivity to the vertical component force F _z when the load detection F _z, F _y by pressure sensation sensor constructed in this manner Will be improved and whether a proper detection operation can be obtained will be described.

3 and 4 show the deformation of the pressure sensor module 50 due to the horizontal component forces F _x and F _y , respectively. Although the pressure sensor module 50 has the adhesive layer 8 having a sufficiently low elastic modulus between the reinforcing body 7 and the pressure cells 1A and 1B as in this example, the pressure cells 1A and 1B have a horizontal component force F _{x of the} load and The reinforcement 7 is also deformed by F _y via the adhesive layer 8. Therefore, the horizontal force components F _x and F _y are distributively transmitted not only to the pressure sensing cells 1A and 1B but also to the reinforcing body 7 to remarkably increase the breaking strength as compared with the conventional pressure sensor having no reinforcing body. You can

When the vertical component force F _z is applied, the pressure sensor module 50 is deformed as shown in FIG. 5, but the vertical component force F _z applied to the pressure receiving plate 4 due to the intervening gap 9 is applied to the reinforcing body 7. The pressure cells 1A and 1B are not directly transmitted but are compressed and deformed by the component force F _z , which causes shear stress in the adhesive layer 8. Thus, the force is also transmitted to the reinforcing body 7 through the adhesive layer 8, but the deformation amount of the pressure sensing cells 1A and 1B due to the vertical component force F _z is very small, and further, the elastic modulus of the adhesive layer 8 is the pressure sense. Since it is sufficiently smaller than the cells 1A and 1B, the initial shear stress is extremely small, and the vertical component force F _z is hardly transmitted to the reinforcement body 7. Therefore, the vertical component force F _z causes strain in the pressure cells 1A and 1B. Is largely unaffected by the reinforcement 7. Therefore, it is possible to maintain the conventional load detection sensitivity with respect to the vertical component force F _z .

As described above, by configuring the pressure sensor module 50, it is possible to increase the breaking strength with respect to the horizontal component forces F _x and F _y without impairing the load detection sensitivity with respect to the vertical component force F _z . The shape of the body 7 does not necessarily have to be a flat plate having the same shape as the pressure cells 1A and 1B as shown in FIG. 1, and as shown in FIG. Various things are possible, such as.

Furthermore, the gap 9 does not have to be limited to between the upper surfaces of the reinforcing body 7 and the adhesive layer 8 and the pressure receiving plate 4 as shown in FIG. 5, and may be provided between the reinforcing body 7 and the groove surface of the unit substrate 2 or both of them. That is, it goes without saying that they may be formed above and below the reinforcing body 7.

[Effects of the Invention] As described above, according to the present invention, a reinforcing plate is arranged between two pressure cells in parallel with each other, and the reinforcing plate and the pressure cell are respectively loaded in three directions. Since it is made to be held by an adhesive layer capable of absorbing strain generated by, further, a gap is provided between the reinforcing body and the pressure receiving plate and / or between the reinforcing plate and the unit substrate. The breaking strength against the horizontal component forces F _z and F _y is increased without impairing the load detection sensitivity of the pressure sensor for the vertical component force F _z . As a result, it has become possible to provide a pressure sensor with breaking strength and load detection sensitivity that can handle various tasks required of a robot.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of the configuration of a pressure sensor module according to the present invention, FIG. 2 is a side view, and FIGS. 3, 4, and 5 are component forces F _{x of} the pressure sensor module of the present invention. FIG. 6 is a side view schematically showing a modified example of F _y and F _z, FIG. 6 is a perspective view showing an example of a reinforcing body shape as another embodiment of the present invention, and FIG. 7 is an example of a conventional pressure sensor. FIG. 8 is a perspective view showing an example of arrangement of strain gauges for detecting three-way component force in the pressure cell, and FIG. 9 is a perspective view showing an example of a conventional pressure sensor having pressure cells having different shapes. Is. 1A, 1B ... Pressure sensor cell, 2 ... Unit substrate, 3 ... Groove, 4 ... Pressure receiving plate, 5,50 ... Pressure sensor module, 6 ... Strain gauge, 7 ... Reinforcement body, 8 ... Adhesive layer 9 ...... gap, 61 ...... F _x detection strain gauges, 62 ...... F _y detection strain gauges, 63 ...... F _z detection strain gauges.

Claims (3)

[Claims] 1. A pressure sensor module is configured by arranging two pressure cells in parallel between a unit substrate and a pressure receiving plate,
A pressure sensor in which a plurality of the pressure sensor modules are arranged so that the distributed load applied on the pressure receiving plate can be decomposed into component forces in three directions orthogonal to each other via the pressure cells to be detected. Reinforcing bodies are arranged in parallel between two pressure cells, and the reinforcing bodies are bonded to the two pressure cells via an adhesive layer capable of absorbing strain generated by the component force in the three directions. And pressure sensor. 2. The pressure sensor according to claim 1, wherein the adhesive layer has a sufficiently lower elastic modulus than the pressure cells and the reinforcing body and a thickness capable of absorbing the strain. Characteristic pressure sensor. 3. The pressure sensor according to claim 1 or 2, wherein a gap is provided between the reinforcing body and the adhesive layer and at least one of the pressure receiving plate and the unit substrate. Pressure sensor characterized by.